Subject: Problem with AutoCAD file From: jonfr@......... Date: Wed, 30 Sep 2009 20:25:25 -0000 (UTC) Hi all, I got the autoCAD file for this seismomter, http://bnordgren.org/seismo/gif_images.htm The autoCAD file appears to contain two layers of drawings, and I am not sure how to change that, so that we can see the drawing clearly. If there is a newer autoCAD file for this seismomter. I would like to get that file, so I can keep up with development progress. Regards, Jón Frímann. __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: BBC News artical From: jonfr@......... Date: Wed, 30 Sep 2009 20:34:52 -0000 (UTC) Hi all, Here is a intersting BBC News artical on how distant earthquakes can weaken fault lines. http://news.bbc.co.uk/2/hi/science/nature/8283873.stm Regards, Jón Frímann. __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Risk of Large earthquake in Californina! From: =?ISO-8859-1?Q?J=F3n_Fr=EDmann?= jonfr@......... Date: Sat, 03 Oct 2009 01:52:43 +0000 Hi all, I've been watching the earthquakes that have been happening in Californina this past minites. This earthquakes look like they are a pre-earthquake squance to a bigger earthquake. I at least estimate that to be a higher chance, then it not to be. I would give it about 60% chance of happening, and about 40% chance of not happening. There is also a small earthquake pattern that I am seeing on local sensor that are also giving me the nessary clues to this. I don't have a time a good timeframe at this momemt. But this might happen in the next 2 - 180 hours time period. I might get a good time frame, but I also might not get one at all. Regards, --=20 J=F3n Fr=EDmann http://www.jonfr.com __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Risk of Large earthquake in Californina! From: "Dave Nelson" davefnelson@....... Date: Sat, 3 Oct 2009 02:08:17 -0000 All. The region where the quakes are occurring is small volcanic area . There have been small eruptions and lava flows within the past century. The China Lake Navy base in that area actually has a geothermal power or heating system which exploits heat from below the lava field . There are small cinder cones clearly visible from highway 395 as you drive through the Owens Valley. However there was a very large quake in that area in 1872 estimated between 7.6 and 8. More likely just a small swarm but who knows . Dave Nelson ~200Km south ----- Original Message ----- From: "Jón Frímann" To: "PSN-Postlist" Sent: Saturday, October 03, 2009 01:52 Subject: Risk of Large earthquake in Californina! Hi all, I've been watching the earthquakes that have been happening in Californina this past minites. This earthquakes look like they are a pre-earthquake squance to a bigger earthquake. I at least estimate that to be a higher chance, then it not to be. I would give it about 60% chance of happening, and about 40% chance of not happening. There is also a small earthquake pattern that I am seeing on local sensor that are also giving me the nessary clues to this. I don't have a time a good timeframe at this momemt. But this might happen in the next 2 - 180 hours time period. I might get a good time frame, but I also might not get one at all. Regards, -- Jón Frímann http://www.jonfr.com __________________________________________________________ Public Seismic Network Mailing List (PSN-L) __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Risk of Large earthquake in Californina! From: Canie canie@........... Date: Fri, 02 Oct 2009 19:38:36 -0700 This is kinda north of the volcanic area and more=20 on the south end of the (dry) Owens lake=20 bed.. they are strike slip quakes.. see the commentary here: http://www.scsn.org/ and here: http://www.scsn.org/commentary/ There's a google earth map:=20 http://quake.usgs.gov/recenteqs/Quakes/ci14519780.kml=20 and I have mine set to include all quakes within=20 the last couple of weeks - you can see the pattern of the quakes.. It is rather interesting.. Canie At 07:08 PM 10/2/2009, you wrote: >All. > >The region where the quakes are occurring is=20 >small volcanic area . There have been small=20 >eruptions and lava flows within the past=20 >century. The China Lake Navy base in that=20 >area actually has a geothermal power or heating=20 >system which exploits heat from below the lava=20 >field . There are small cinder cones clearly=20 >visible from highway 395 as you drive through the Owens Valley. > >However there was a very large quake in that=20 >area in 1872 estimated between 7.6 and 8. > >More likely just a small swarm but who knows . > >Dave Nelson > >~200Km south > > > > > > >----- Original Message ----- From: "J=F3n Fr=EDmann" >To: "PSN-Postlist" >Sent: Saturday, October 03, 2009 01:52 >Subject: Risk of Large earthquake in Californina! > > >Hi all, > >I've been watching the earthquakes that have been happening in >Californina this past minites. This earthquakes look like they are a >pre-earthquake squance to a bigger earthquake. I at least estimate that >to be a higher chance, then it not to be. I would give it about 60% >chance of happening, and about 40% chance of not happening. There is >also a small earthquake pattern that I am seeing on local sensor that >are also giving me the nessary clues to this. > >I don't have a time a good timeframe at this momemt. But this might >happen in the next 2 - 180 hours time period. I might get a good time >frame, but I also might not get one at all. > >Regards, >-- >J=F3n Fr=EDmann > >http://www.jonfr.com > >__________________________________________________________ > >Public Seismic Network Mailing List (PSN-L) > >To leave this list email PSN-L-REQUEST@.............. with >the body of the message (first line only): unsubscribe >See http://www.seismicnet.com/maillist.html for more information. > > >__________________________________________________________ > >Public Seismic Network Mailing List (PSN-L) > >To leave this list email=20 >PSN-L-REQUEST@.............. with the body of=20 >the message (first line only): unsubscribe >See http://www.seismicnet.com/maillist.html for more information. __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: RE: Risk of Large earthquake in California! From: "Kareem" system98765@............. Date: Fri, 2 Oct 2009 20:32:46 -0700 We do have a full moon coming up this Sunday; so if there are = correlations with the full/new moons and the occurrence of significant seismic events = and some researchers believe this to be the case, then I would tend to agree that the chances are certainly much higher these next few days. -----Original Message----- From: psn-l-request@.............. [mailto:psn-l-request@............... = On Behalf Of J=F3n Fr=EDmann Sent: Friday, October 02, 2009 6:53 PM To: PSN-Postlist Subject: Risk of Large earthquake in Californina! Hi all, I've been watching the earthquakes that have been happening in Californina this past minites. This earthquakes look like they are a pre-earthquake squance to a bigger earthquake. I at least estimate that to be a higher chance, then it not to be. I would give it about 60% chance of happening, and about 40% chance of not happening. There is also a small earthquake pattern that I am seeing on local sensor that are also giving me the nessary clues to this. I don't have a time a good timeframe at this momemt. But this might happen in the next 2 - 180 hours time period. I might get a good time frame, but I also might not get one at all. Regards, --=20 J=F3n Fr=EDmann http://www.jonfr.com __________________________________________________________ Public Seismic Network Mailing List (PSN-L) __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Risk of Large earthquake in Californina! From: "Dave Nelson" davefnelson@....... Date: Sat, 3 Oct 2009 03:39:24 -0000 I agree-- very interesting . Dave ----- Original Message ----- From: "Canie" To: Sent: Saturday, October 03, 2009 02:38 Subject: Re: Risk of Large earthquake in Californina! This is kinda north of the volcanic area and more on the south end of the (dry) Owens lake bed.. they are strike slip quakes.. see the commentary here: http://www.scsn.org/ and here: http://www.scsn.org/commentary/ There's a google earth map: http://quake.usgs.gov/recenteqs/Quakes/ci14519780.kml and I have mine set to include all quakes within the last couple of weeks - you can see the pattern of the quakes.. It is rather interesting.. Canie At 07:08 PM 10/2/2009, you wrote: >All. > >The region where the quakes are occurring is small volcanic area . There >have been small eruptions and lava flows within the past century. The China >Lake Navy base in that area actually has a geothermal power or heating >system which exploits heat from below the lava field . There are small >cinder cones clearly visible from highway 395 as you drive through the >Owens Valley. > >However there was a very large quake in that area in 1872 estimated between >7.6 and 8. > >More likely just a small swarm but who knows . > >Dave Nelson > >~200Km south > > > > > > >----- Original Message ----- From: "Jón Frímann" >To: "PSN-Postlist" >Sent: Saturday, October 03, 2009 01:52 >Subject: Risk of Large earthquake in Californina! > > >Hi all, > >I've been watching the earthquakes that have been happening in >Californina this past minites. This earthquakes look like they are a >pre-earthquake squance to a bigger earthquake. I at least estimate that >to be a higher chance, then it not to be. I would give it about 60% >chance of happening, and about 40% chance of not happening. There is >also a small earthquake pattern that I am seeing on local sensor that >are also giving me the nessary clues to this. > >I don't have a time a good timeframe at this momemt. But this might >happen in the next 2 - 180 hours time period. I might get a good time >frame, but I also might not get one at all. > >Regards, >-- >Jón Frímann > >http://www.jonfr.com > >__________________________________________________________ > >Public Seismic Network Mailing List (PSN-L) > >To leave this list email PSN-L-REQUEST@.............. with >the body of the message (first line only): unsubscribe >See http://www.seismicnet.com/maillist.html for more information. > > >__________________________________________________________ > >Public Seismic Network Mailing List (PSN-L) > >To leave this list email PSN-L-REQUEST@.............. with the body of the >message (first line only): unsubscribe >See http://www.seismicnet.com/maillist.html for more information. __________________________________________________________ Public Seismic Network Mailing List (PSN-L) __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Risk of Large earthquake in Californina! From: Barry Lotz barry_lotz@............. Date: Sat, 3 Oct 2009 09:10:34 -0700 (PDT) All I did a study years ago. I won't go into it no. I divided California and we= stern Nevada into an east and west zone (relating to the two major fault li= nes). I then plotted energy dissipation related to latitude. If memory serv= es me well this was an area that was over due. I guess time will tell. I wr= ote the program in Basic. Maybe I'll dig it up and refresh my memory. Barry=20 --- On Fri, 10/2/09, Dave Nelson wrote: From: Dave Nelson Subject: Re: Risk of Large earthquake in Californina! To: psn-l@.............. Date: Friday, October 2, 2009, 7:08 PM All. The region where the quakes are occurring is small=A0 volcanic area . There= have been small eruptions and lava flows within the past century. The Chin= a Lake Navy base in that area=A0 actually has a geothermal power or heating= system which exploits heat from below=A0 the lava field . There are small = cinder cones clearly visible from highway 395 as you drive through the Owen= s Valley. However there was a very large quake in that area in 1872 estimated between= 7.6 and 8. More likely just a small swarm but who knows . Dave Nelson ~200Km south ----- Original Message ----- From: "J=F3n Fr=EDmann" To: "PSN-Postlist" Sent: Saturday, October 03, 2009 01:52 Subject: Risk of Large earthquake in Californina! Hi all, I've been watching the earthquakes that have been happening in Californina this past minites. This earthquakes look like they are a pre-earthquake squance to a bigger earthquake. I at least estimate that to be a higher chance, then it not to be. I would give it about 60% chance of happening, and about 40% chance of not happening. There is also a small earthquake pattern that I am seeing on local sensor that are also giving me the nessary clues to this. I don't have a time a good timeframe at this momemt. But this might happen in the next 2 - 180 hours time period. I might get a good time frame, but I also might not get one at all. Regards, -- J=F3n Fr=EDmann http://www.jonfr.com __________________________________________________________ Public Seismic Network Mailing List (PSN-L) __________________________________________________________ Public Seismic Network Mailing List (PSN-L)
All
I did a study years ago. I won't go in= to it no. I divided California and western Nevada into an east and west zon= e (relating to the two major fault lines). I then plotted energy dissipatio= n related to latitude. If memory serves me well this was an area that was o= ver due. I guess time will tell. I wrote the program in Basic. Maybe I'll d= ig it up and refresh my memory.
Barry
--- On Fri, 10/2/09, Dave N= elson <davefnelson@.......> wrote:

From: Dave Nelson <davefnelson@.......>
Subject: Re: Risk= of Large earthquake in Californina!
To: psn-l@............. om
Date: Friday, October 2, 2009, 7:08 PM


All.

The region where the quakes are occurring is small  volcanic area . There have been small eruptions and lava flows within the = past century. The China Lake Navy base in that area  actually has a ge= othermal power or heating system which exploits heat from below  the l= ava field . There are small cinder cones clearly visible from highway 395 a= s you drive through the Owens Valley.

However there was a very large= quake in that area in 1872 estimated between 7.6 and 8.

More likely= just a small swarm but who knows .

Dave Nelson

~200Km south<= br>





----- Original Message ----- From: "J=F3n Fr=EDm= ann" <jonfr@.........>
To: "PSN-Postlist" <PSN-L@..............>
Sent: Saturday, October 03, 2009 01:52=
Subject: Risk of Large earthquake in Californina!


Hi all,

I've been watching the earthquakes that have been happening in=
Californina this past minites. This earthquakes look like they are apre-earthquake squance to a bigger earthquake. I at least estimate thatto be a higher chance, then it not to be. I would give it about 60%
cha= nce of happening, and about 40% chance of not happening. There is
also a= small earthquake pattern that I am seeing on local sensor that
are also= giving me the nessary clues to this.

I don't have a time a good tim= eframe at this momemt. But this might
happen in the next 2 - 180 hours t= ime period. I might get a good time
frame, but I also might not get one = at all.

Regards,
-- J=F3n Fr=EDmann

http://www.jonfr.com

______________= ____________________________________________

Public Seismic Network = Mailing List (PSN-L)

To leave this list email PSN-L-REQUEST@.............. with
the b= ody of the message (first line only): unsubscribe
See http://www.seismicnet.c= om/maillist.html for more information.


_____________________= _____________________________________

Public Seismic Network Mailing= List (PSN-L)

To leave this list email PSN-L-REQUEST@.............. with the body of the message (first line= only): unsubscribe
See http://www.seismicnet.com/maillist.html for more = information.
Subject: RE: Risk of Large earthquake in Californina! From: "Stephen Hammond" shammon1@............. Date: Sat, 3 Oct 2009 17:18:37 -0700 This is not uncommon in this region. The following comes from Richter, (Elementaly Seismology, C.F. Richter, 1958, p.71 =96 Earthquake Swarms) = =93 Certain localities are frequently visited by earthquake swarms, long = series of large and small shocks with one outstanding principal event. Such = swarms are common in volcanic regions; they often occur before and during eruptions=94 snip-snip some text =93 sometimes as many as 100 a day are occasionally recorded at the Haiwee seismological station in Owens = Valley.=94=20 =20 Regards, Steve Hammond PSN Aptos, CA =20 =20 =20 From: psn-l-request@.............. [mailto:psn-l-request@............... = On Behalf Of Barry Lotz Sent: Saturday, October 03, 2009 9:11 AM To: psn-l@.............. Subject: Re: Risk of Large earthquake in Californina! =20 All I did a study years ago. I won't go into it no. I divided California and western Nevada into an east and west zone (relating to the two major = fault lines). I then plotted energy dissipation related to latitude. If memory serves me well this was an area that was over due. I guess time will = tell. I wrote the program in Basic. Maybe I'll dig it up and refresh my memory. Barry=20 --- On Fri, 10/2/09, Dave Nelson wrote: From: Dave Nelson Subject: Re: Risk of Large earthquake in Californina! To: psn-l@.............. Date: Friday, October 2, 2009, 7:08 PM All. The region where the quakes are occurring is small volcanic area . = There have been small eruptions and lava flows within the past century. The = China Lake Navy base in that area actually has a geothermal power or heating system which exploits heat from below the lava field . There are small cinder cones clearly visible from highway 395 as you drive through the = Owens Valley. However there was a very large quake in that area in 1872 estimated = between 7.6 and 8. More likely just a small swarm but who knows . Dave Nelson ~200Km south ----- Original Message ----- From: "J=F3n Fr=EDmann" To: "PSN-Postlist" Sent: Saturday, October 03, 2009 01:52 Subject: Risk of Large earthquake in Californina! Hi all, I've been watching the earthquakes that have been happening in Californina this past minites. This earthquakes look like they are a pre-earthquake squance to a bigger earthquake. I at least estimate that to be a higher chance, then it not to be. I would give it about 60% chance of happening, and about 40% chance of not happening. There is also a small earthquake pattern that I am seeing on local sensor that are also giving me the nessary clues to this. I don't have a time a good timeframe at this momemt. But this might happen in the next 2 - 180 hours time period. I might get a good time frame, but I also might not get one at all. Regards, -- J=F3n Fr=EDmann http://www.jonfr.com __________________________________________________________ Public Seismic Network Mailing List (PSN-L) __________________________________________________________ Public Seismic Network Mailing List (PSN-L) See http://www.seismicnet.com/maillist.html for more information. =20

This is not uncommon in this region. The following comes = from Richter, (Elementaly Seismology, C.F. Richter, 1958, p.71 – = Earthquake Swarms) “ Certain localities are frequently visited by earthquake swarms, = long series of large and small shocks with one outstanding principal event. = Such swarms are common in volcanic regions; they often occur before and = during eruptions” snip-snip some text “ sometimes as many as 100 a = day are occasionally recorded at the Haiwee seismological station in Owens = Valley.”

 

Regards, Steve Hammond PSN Aptos, = CA

 

 

 

From:= = psn-l-request@.............. [mailto:psn-l-request@............... On Behalf Of Barry Lotz
Sent: Saturday, October 03, 2009 9:11 AM
To: psn-l@..............
Subject: Re: Risk of Large earthquake in = Californina!

 

All
I did a study years ago. I won't go into it no. I divided California = and western Nevada into an east and west zone (relating to the two major = fault lines). I then plotted energy dissipation related to latitude. If = memory serves me well this was an area that was over due. I guess time will = tell. I wrote the program in Basic. Maybe I'll dig it up and refresh my = memory.
Barry
--- On Fri, 10/2/09, Dave Nelson = <davefnelson@.......> wrote:


From: Dave Nelson <davefnelson@.......>
Subject: Re: Risk of Large earthquake in Californina!
To: psn-l@..............
Date: Friday, October 2, 2009, 7:08 PM


All.

The region where the quakes are occurring is small  volcanic area = . There have been small eruptions and lava flows within the past = century. The China Lake Navy base in that area  actually has a geothermal = power or heating system which exploits heat from below  the lava field . = There are small cinder cones clearly visible from highway 395 as you drive = through the Owens Valley.

However there was a very large quake in that area in 1872 estimated = between 7.6 and 8.

More likely just a small swarm but who knows .

Dave Nelson

~200Km south






----- Original Message ----- From: "J=F3n Fr=EDmann" <jonfr@.........>
To: "PSN-Postlist" <PSN-L@..............&g= t;
Sent: Saturday, October 03, 2009 01:52
Subject: Risk of Large earthquake in Californina!


Hi all,

I've been watching the earthquakes that have been happening in
Californina this past minites. This earthquakes look like they are = a
pre-earthquake squance to a bigger earthquake. I at least estimate = that
to be a higher chance, then it not to be. I would give it about = 60%
chance of happening, and about 40% chance of not happening. There = is
also a small earthquake pattern that I am seeing on local sensor = that
are also giving me the nessary clues to this.

I don't have a time a good timeframe at this momemt. But this = might
happen in the next 2 - 180 hours time period. I might get a good = time
frame, but I also might not get one at all.

Regards,
-- J=F3n Fr=EDmann

http://www.jonfr.com

__________________________________________________________

Public Seismic Network Mailing List (PSN-L)

To leave this list email PSN-L-REQUEST@SEIS= MICNET.COM with
the body of the message (first line only): unsubscribe
See http://www.seismicnet.com/maillist.html for more information.


__________________________________________________________

Public Seismic Network Mailing List (PSN-L)

To leave this list email PSN-L-REQUEST@SEIS= MICNET.COM with the body of the message (first line only): unsubscribe
See http://www.seismicnet.com/maillist.html for more information.

 =

Subject: RE: Risk of Large earthquake in Californina! From: =?ISO-8859-1?Q?J=F3n_Fr=EDmann?= jonfr@......... Date: Sun, 04 Oct 2009 01:38:48 +0000 Hello, As that may be. The risk of a large earthquake at this area is still remaning. Weather my prediction will come true is a other issue, they do fail on a farily routine basic, even for my best effort trying to read into earthquake patterns and the data collected. This area might be volcanic. But there has been little activie in this area for some time now, the unceartinys are great. See more here, http://www.volcano.si.edu/world/region.cfm?rnum=3D1203 The current risk of a large earthquake are dropping, but they are still there. Regards, J=C3=B3n Fr=C3=ADmann. On lau, 2009-10-03 at 17:18 -0700, Stephen Hammond wrote: > This is not uncommon in this region. The following comes from Richter, > (Elementaly Seismology, C.F. Richter, 1958, p.71 =E2=80=93 Earthquake Swa= rms) > =E2=80=9C Certain localities are frequently visited by earthquake swarms,= long > series of large and small shocks with one outstanding principal event. > Such swarms are common in volcanic regions; they often occur before > and during eruptions=E2=80=9D snip-snip some text =E2=80=9C sometimes as = many as 100 a > day are occasionally recorded at the Haiwee seismological station in > Owens Valley.=E2=80=9D=20 >=20 > =20 >=20 > Regards, Steve Hammond PSN Aptos, CA >=20 > =20 >=20 > =20 >=20 > =20 >=20 > From: psn-l-request@.............. > [mailto:psn-l-request@............... On Behalf Of Barry Lotz > Sent: Saturday, October 03, 2009 9:11 AM > To: psn-l@.............. > Subject: Re: Risk of Large earthquake in Californina! >=20 >=20 > =20 >=20 > All > I did a study years ago. I won't go into it no. I divided California > and western Nevada into an east and west zone (relating to the two > major fault lines). I then plotted energy dissipation related to > latitude. If memory serves me well this was an area that was over due. > I guess time will tell. I wrote the program in Basic. Maybe I'll dig > it up and refresh my memory. > Barry=20 > --- On Fri, 10/2/09, Dave Nelson wrote: >=20 >=20 > From: Dave Nelson > Subject: Re: Risk of Large earthquake in Californina! > To: psn-l@.............. > Date: Friday, October 2, 2009, 7:08 PM >=20 >=20 > All. >=20 > The region where the quakes are occurring is small volcanic area . > There have been small eruptions and lava flows within the past > century. The China Lake Navy base in that area actually has a > geothermal power or heating system which exploits heat from below the > lava field . There are small cinder cones clearly visible from highway > 395 as you drive through the Owens Valley. >=20 > However there was a very large quake in that area in 1872 estimated > between 7.6 and 8. >=20 > More likely just a small swarm but who knows . >=20 > Dave Nelson >=20 > ~200Km south >=20 >=20 >=20 >=20 >=20 >=20 > ----- Original Message ----- From: "J=C3=B3n Fr=C3=ADmann" > To: "PSN-Postlist" > Sent: Saturday, October 03, 2009 01:52 > Subject: Risk of Large earthquake in Californina! >=20 >=20 > Hi all, >=20 > I've been watching the earthquakes that have been happening in > Californina this past minites. This earthquakes look like they are a > pre-earthquake squance to a bigger earthquake. I at least estimate > that > to be a higher chance, then it not to be. I would give it about 60% > chance of happening, and about 40% chance of not happening. There is > also a small earthquake pattern that I am seeing on local sensor that > are also giving me the nessary clues to this. >=20 > I don't have a time a good timeframe at this momemt. But this might > happen in the next 2 - 180 hours time period. I might get a good time > frame, but I also might not get one at all. >=20 > Regards, > -- J=C3=B3n Fr=C3=ADmann >=20 > http://www.jonfr.com >=20 > __________________________________________________________ >=20 > Public Seismic Network Mailing List (PSN-L) >=20 > To leave this list email PSN-L-REQUEST@.............. with > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. >=20 >=20 > __________________________________________________________ >=20 > Public Seismic Network Mailing List (PSN-L) >=20 > To leave this list email PSN-L-REQUEST@.............. with the body of > the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. >=20 >=20 >=20 > =20 >=20 __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Deep quakes like the one in the Phillippines From: Thomas Dick dickthomas01@............. Date: Sun, 04 Oct 2009 10:22:52 -0500 How many of you have gotten good copy on quakes deeper than this? Lay & Wallace indicate that 650 km and more is rare. __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Deep quakes like the one in the Phillippines From: Brett Nordgren brett3nt@............. Date: Sun, 04 Oct 2009 11:43:38 -0400 Thomas, Thanks for pointing that out. I should have noticed, considering the almost complete absence of surface waves. It gives a great opportunity, though, to see all the body phases which are usually obscured by the big surface stuff. I'm pretty sure that's the deepest that we've seen. Regards, Brett At 10:22 AM 10/4/2009 -0500, you wrote: >How many of you have gotten good copy on quakes deeper than this? Lay & >Wallace indicate that 650 km and more is rare. Watch our wiggles http://bnordgren.org/seismo/gif_images.htm or watch some very very good wiggles http://aslwww.cr.usgs.gov/Seismic_Data/telemetry_data/ANMO_24hr.html __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Deep quakes like the one in the Phillippines From: "tchannel" tchannel@............ Date: Sun, 4 Oct 2009 09:45:01 -0600 Hi Dick, I did not get this one, but looking at my log sheet I have recorded: 385km Japan 547km Argentina 487km Sea of Okhotsk 303km Japan All from this location in Idaho USA Ted ----- Original Message ----- From: "Thomas Dick" To: Sent: Sunday, October 04, 2009 9:22 AM Subject: Deep quakes like the one in the Phillippines > How many of you have gotten good copy on quakes deeper than this? Lay & > Wallace indicate that 650 km and more is rare. > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with the body of the > message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Deep quakes like the one in the Phillippines From: Thomas Dick dickthomas01@............. Date: Sun, 04 Oct 2009 12:36:44 -0500 I did not get this one, but looking at my log sheet I have recorded: > 385km Japan > 547km Argentina > 487km Sea of Okhotsk > 303km Japan > Thanks for info, it was quiet here this morning. __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Deep quakes like the one in the Phillippines From: Dave Nelson dave.nelson@............... Date: Mon, 05 Oct 2009 10:29:16 +1100 Thomas and Co keep an eye on the quakes particularly in the New Zealand to Tonga region (The Tonga Kermadec Trench) and you will regularly see events >600km in depth. Some years back this same topic came up and I remember commenting on the areas had I had done plots of depth V's locating and it was a good personal study into subduction zones... the angle of the subducting slab depths they were getting to etc. Look for regions where the plate motions are very high >6.5cm / year to show the regions of the deepest quakes. As I also mentioned that last time look at Alan Jone's software that plots all the data for you in 3 dimensions :) Cheers Dave Nelson Sydney Oz At 11:43 AM 10/4/2009 -0400, you wrote: >Thomas, > >Thanks for pointing that out. I should have noticed, considering the >almost complete absence of surface waves. It gives a great opportunity, >though, to see all the body phases which are usually obscured by the big >surface stuff. I'm pretty sure that's the deepest that we've seen. > >Regards, >Brett > >At 10:22 AM 10/4/2009 -0500, you wrote: >>How many of you have gotten good copy on quakes deeper than this? Lay & >>Wallace indicate that 650 km and more is rare. > > > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Deep quakes like the one in the Phillippines From: Thomas Dick dickthomas01@............. Date: Sun, 04 Oct 2009 19:44:38 -0500 Hey Dave, What did you mean by " Alan Jone's software that plots all the data for you in 3 dimensions"? Not familiar with this software. Is this the Purdue University Alan Jones? __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Deep quakes like the one in the Phillippines From: Dave Nelson dave.nelson@............... Date: Mon, 05 Oct 2009 14:23:17 +1100 Hey Thomas http://pods.binghamton.edu/~ajones/ yup if you havent got his progs they are well worth it :) Dave At 07:44 PM 10/4/2009 -0500, you wrote: >Hey Dave, > >What did you mean by " Alan Jone's software that plots all the data for >you in 3 dimensions"? Not familiar with this software. Is this the Purdue >University Alan Jones? >__________________________________________________________ __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Many large earthquakes From: jonfr@......... Date: Thu, 8 Oct 2009 02:39:58 -0000 (UTC) Hi all, There are quite many earthquakes happening at this moment. Just now there was a Mw6.9 earthquake (02:12 UTC 8. October 2009). This is quite interesting. I am expecting more large earthquakes. I am also expecting nearby faults to be activated by this earthquake sequence. Regards, Jón Frímann. __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: RE: Many large earthquakes From: "Kareem" system98765@............. Date: Wed, 7 Oct 2009 20:18:25 -0700 Yeah, seems to be quite active sequences all around. As for that area, = it seems that since the 9.0 event few years back, the sequences there have included numerous 7.0 and higher events. -----Original Message----- From: psn-l-request@.............. [mailto:psn-l-request@............... = On Behalf Of jonfr@......... Sent: Wednesday, October 07, 2009 7:40 PM To: psn-l@.............. Subject: Many large earthquakes Hi all, There are quite many earthquakes happening at this moment. Just now = there was a Mw6.9 earthquake (02:12 UTC 8. October 2009). This is quite interesting. I am expecting more large earthquakes. I am also expecting nearby faults to be activated by this earthquake = sequence. Regards, J=F3n Fr=EDmann. __________________________________________________________ Public Seismic Network Mailing List (PSN-L) __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: RE: Many large earthquakes From: jonfr@......... Date: Fri, 9 Oct 2009 00:28:36 -0000 (UTC) Hi all, This earthquake swarm continues, with a little slow down it seems. The mag 7.0 earthquakes appears to have stopped, for now anyway. But there are still many mag 6.0 earthquakes happening. Regards, Jón Frímann. > Yeah, seems to be quite active sequences all around. As for that area, it > seems that since the 9.0 event few years back, the sequences there have > included numerous 7.0 and higher events. > > > > -----Original Message----- > From: psn-l-request@.............. [mailto:psn-l-request@............... > On > Behalf Of jonfr@......... > Sent: Wednesday, October 07, 2009 7:40 PM > To: psn-l@.............. > Subject: Many large earthquakes > > Hi all, > > There are quite many earthquakes happening at this moment. Just now there > was a Mw6.9 earthquake (02:12 UTC 8. October 2009). > > This is quite interesting. I am expecting more large earthquakes. I am > also expecting nearby faults to be activated by this earthquake sequence. > > Regards, > Jón Frímann. > > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. > > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Equipment Search From: "GPayton" gpayton@............. Date: Sat, 10 Oct 2009 08:55:28 -0500 October 10,2009 Good Morning All, I am acquiring a vertical sensor and would like to get a horizontal (or two ideally). I've looked into the two units from the UK (SEP and HS-3). If anyone has or spots one, please contact me directly ( gpayton at uspaytons dot com. ) Thank you, Jerry Payton
October 10,2009
 
Good Morning All,
 
I am acquiring a vertical sensor and would like = to get a=20 horizontal (or two ideally).   I've looked into the two units = from the=20 UK (SEP and HS-3).
 
If anyone has or spots one, please contact me = directly=20 (  gpayton at uspaytons dot com.  )
 
Thank you,
Jerry Payton
Subject: Torsion Seismometer in a jar From: kevin.mckee@....... Date: Thu, 15 Oct 2009 16:27:19 -0400 Hi - I just joined this e-mail list, and noticed some of the discussion about the seismometer project I posted at http://tinkeringcaveman.googlepages.com/home There seemed to be some concern that the system would perform poorly or be very noisy. There was some discussion over the LED being a cause for noise. I performed a number of tests before I completed the seismometer (several years ago now) to satisfy my own concerns in that regard. I used various incandescent bulbs, LEDs and sensors, and in some cases, locked the pendulum in a stationary position to test whether the sensor was picking up noise from the LED. In fact, I got a flat line even when the amplifier was maxed out--the LED was significantly quieter than other light sources. I've actually found the two devices that I've built (facing orthogonally) to be very sensitive. I've put together a rough distance-magnitude threshold detection plot that I can forward to anyone who is interested. The weakest quake I've detected is a magnitude 2.0, about 0.05 degrees (about 3 miles) away. The common phases are easily picked out of the signal, depending on the quake origin. The larger factor in the devices' sensitivity is that I mounted them on a basement slab under the stairs to my front porch, which means that they detects the comings and goings of my family too (I sometimes used this fact to check up on my daughters' returns from dates). I believe that I am detecting microseismic background with the instrument too, rather than air currents. Regarding the fact that the sensor is a displacement sensor vice a velocity sensor--I don't see that as a problem. As with a capacitive /radio frequency force-balance sensor, electronic filters and amplifiers can be used to translate the signal into a velocity response, if that is what is desired. In fact using the appropriate filter amplifier combination gets around any concerns like those expressed about the resolution of the optical sensing devices--electronic integration works very well for that. Kevin McKee, Burke, VA __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Torsion Seismometer in a jar From: ChrisAtUpw@....... Date: Thu, 15 Oct 2009 18:13:04 EDT In a message dated 15/10/2009 21:27:46 GMT Daylight Time, kevin.mckee@....... writes: There seemed to be some concern that the system would perform poorly or be very noisy. There was some discussion over the LED being a cause for noise. I used various incandescent bulbs, LEDs and sensors, and in some cases, locked the pendulum in a stationary position to test whether the sensor was picking up noise from the LED. In fact, I got a flat line even when the amplifier was maxed out--the LED was significantly quieter than other light sources. Hi Kevin, You seem to be experiencing apparatus problems. Ordinary LEDs are much more noisy than superbright or IR LEDs. Both vary in light output by about x5 between 0 and 100 C. The is a HUGE variation. They are both more noisy than a filament bulb driven from a regulated voltage source. Your flat line response was probably due to low gain. You should be able to pick up microseisms all the time. You can build a very good detector using two large area Si photocells BPW34 connected to a differential amplifier. I get a noise level of about 14 nano metres. You can't get adequate stability with a single detector or with a LED which is not temperature compensated. Phototransistors are extremely noisy compared to photodiodes. You can get very fine Nichrome wire which makes a good suspension. Alternatively, you can use a single glass or carbon filament. Regards, Chris Chapman
In a message dated 15/10/2009 21:27:46 GMT Daylight Time,=20 kevin.mckee@....... writes:
There=20 seemed to be some concern that the system would perform poorly or be ver= y=20 noisy. There was some discussion over the LED being a cause for noise.= I used=20 various incandescent bulbs, LEDs and sensors, and in some cases, locked= the=20 pendulum in a stationary position to test whether the sensor was picking= up=20 noise from the LED. In fact, I got a flat line even when the amplifier= was=20 maxed out--the LED was significantly quieter than other light sources.= =20
Hi Kevin,
 
    You seem to be experiencing apparatus problem= s.=20 Ordinary LEDs are much more noisy than superbright or IR LEDs. Both vary= in=20 light output by about x5 between 0 and 100 C. The is a HUGE variation. The= y are=20 both more noisy than a filament bulb driven from a regulated voltage sourc= e.=20 Your flat line response was probably due to low gain. You should be able= to pick=20 up microseisms all the time.
    You can build a very good detector using two= large=20 area Si photocells BPW34 connected to a differential amplifier. I get a no= ise=20 level of about 14 nano metres. You can't get adequate stability with a sin= gle=20 detector or with a LED which is not temperature compensated. Phototransist= ors=20 are extremely noisy compared to photodiodes. You can get very fine Nichrom= e wire=20 which makes a good suspension. Alternatively, you can use a single gl= ass or=20 carbon filament.
 
    Regards,
 
    Chris Chapman
 
    
Subject: Re: Torsion Seismometer in a jar From: "tchannel" tchannel@............ Date: Thu, 15 Oct 2009 17:18:47 -0600 Hi Chris, the two large area Si photocells BPW34 connected to a = differential amplifier, sound like something I would like to try. Could = you help me with a simple schematic of this, even a sketch? Does the = amp just use easy to find op amps? Thanks, Ted ----- Original Message -----=20 From: ChrisAtUpw@.......... To: psn-l@................. Sent: Thursday, October 15, 2009 4:13 PM Subject: Re: Torsion Seismometer in a jar In a message dated 15/10/2009 21:27:46 GMT Daylight Time, = kevin.mckee@....... writes: There seemed to be some concern that the system would perform poorly = or be very noisy. There was some discussion over the LED being a cause = for noise. I used various incandescent bulbs, LEDs and sensors, and in = some cases, locked the pendulum in a stationary position to test whether = the sensor was picking up noise from the LED. In fact, I got a flat line = even when the amplifier was maxed out--the LED was significantly quieter = than other light sources.=20 Hi Kevin, You seem to be experiencing apparatus problems. Ordinary LEDs are = much more noisy than superbright or IR LEDs. Both vary in light output = by about x5 between 0 and 100 C. The is a HUGE variation. They are both = more noisy than a filament bulb driven from a regulated voltage source. = Your flat line response was probably due to low gain. You should be able = to pick up microseisms all the time. You can build a very good detector using two large area Si = photocells BPW34 connected to a differential amplifier. I get a noise = level of about 14 nano metres. You can't get adequate stability with a = single detector or with a LED which is not temperature compensated. = Phototransistors are extremely noisy compared to photodiodes. You can = get very fine Nichrome wire which makes a good suspension. = Alternatively, you can use a single glass or carbon filament.=20 Regards, Chris Chapman
Hi Chris,  the two large area Si photocells BPW34 connected to = a=20 differential amplifier, sound like something I would like to try.  = Could=20 you help me with a simple schematic of this, even a sketch?   = Does the=20 amp just use easy to find op amps?
 
Thanks, Ted
----- Original Message -----
From:=20 ChrisAtUpw@.......
Sent: Thursday, October 15, = 2009 4:13=20 PM
Subject: Re: Torsion = Seismometer in a=20 jar

In a message dated 15/10/2009 21:27:46 GMT Daylight Time, kevin.mckee@....... = writes:
There=20 seemed to be some concern that the system would perform poorly or be = very=20 noisy. There was some discussion over the LED being a cause for = noise. I=20 used various incandescent bulbs, LEDs and sensors, and in some = cases, locked=20 the pendulum in a stationary position to test whether the sensor was = picking=20 up noise from the LED. In fact, I got a flat line even when the = amplifier=20 was maxed out--the LED was significantly quieter than other light = sources.=20
Hi Kevin,
 
    You seem to be experiencing apparatus = problems.=20 Ordinary LEDs are much more noisy than superbright or IR LEDs. Both = vary in=20 light output by about x5 between 0 and 100 C. The is a HUGE variation. = They=20 are both more noisy than a filament bulb driven from a regulated = voltage=20 source. Your flat line response was probably due to low gain. You = should be=20 able to pick up microseisms all the time.
    You can build a very good detector using = two=20 large area Si photocells BPW34 connected to a differential amplifier. = I get a=20 noise level of about 14 nano metres. You can't get adequate stability = with a=20 single detector or with a LED which is not temperature compensated.=20 Phototransistors are extremely noisy compared to photodiodes. You can = get very=20 fine Nichrome wire which makes a good suspension. Alternatively, = you can=20 use a single glass or carbon filament.
 
    Regards,
 
    Chris Chapman
 
    
Subject: Re: Torsion Seismometer in a jar From: ChrisAtUpw@....... Date: Thu, 15 Oct 2009 21:49:17 EDT In a message dated 16/10/2009, tchannel@............ writes: Hi Chris, the two large area Si photocells BPW34 connected to a differential amplifier, sound like something I would like to try. Could you help me with a simple schematic of this, even a sketch? Does the amp just use easy to find op amps? Thanks, Ted Hi Ted, Check out the notes and the circuit at _http://jclahr.com/science/psn/chapman/photo_detect/index.html_ (http://jclahr.com/science/psn/chapman/photo_detect/index.html) This circuit works fine. You need the INA118 or similar to get the very high CMRR common mode rejection ratio. You may need to alter filter values to suit your application. The photocells drive current into the opamps, so they run at 0V and there is no leakage current. I usually use a miniature filament bulb driven from a stabilised voltage and a lens to give a ~parallel light beam. You can use an IR LED if you provide an auxiliary Si photodiode and a feedback amplifier to stabilise the photo output. Otherwise it drifts all over the place. I use two small razor blades for the sides of the shutter, painted matt black, but with clean edges. They move just clear of the surface of the photocells. I measured the noise level at about 14 nano metres. There is inevitably some heat associated with the bulb. I suggest placing the bulb in a separate housing on top of the sensor. You under run the bulb voltage supply to give ~infinite life. Regards, Chris Chapman
In a message dated 16/10/2009, tchannel@............ writes:
Hi Chris,  the two large area Si photocells BPW34 connected to= a=20 differential amplifier, sound like something I would like to try. = Could=20 you help me with a simple schematic of this, even a sketch?  = Does=20 the amp just use easy to find op amps?
 
Thanks, Ted
Hi Ted,
 
    Check out the notes and the circuit at  = htt= p://jclahr.com/science/psn/chapman/photo_detect/index.html
    This circuit works fine. You need the INA118= or=20 similar to get the very high CMRR common mode rejection ratio. You may nee= d to=20 alter filter values to suit your application. The photocells drive current= into=20 the opamps, so they run at 0V and there is no leakage current. I usually= use=20 a miniature filament bulb driven from a stabilised voltage and a lens= to=20 give a ~parallel light beam. You can use an IR LED if you provide an auxil= iary=20 Si photodiode and a feedback amplifier to stabilise the photo output. Othe= rwise=20 it drifts all over the place. I use two small razor blades for the sides= of the=20 shutter, painted matt black, but with clean edges. They move just clear of= the=20 surface of the photocells.  I measured the noise level at about 14 na= no=20 metres. There is inevitably some heat associated with the bulb. I suggest= =20 placing the bulb in a separate housing on top of the sensor. You under run= the=20 bulb voltage supply to give ~infinite life.
 
    Regards,
 
    Chris Chapman
Subject: Re: Torsion Seismometer in a jar From: "Geoffrey" gmvoeth@........... Date: Thu, 15 Oct 2009 19:07:15 -0700 If you used a current source to keep a steady 10ma or 20 ma to the LED would that not be adequate stability for the light output also ? ----- Original Message ----- From: "tchannel" To: Sent: Thursday, October 15, 2009 4:18 PM Subject: Re: Torsion Seismometer in a jar Hi Chris, the two large area Si photocells BPW34 connected to a differential amplifier, sound like something I would like to try. Could you help me with a simple schematic of this, even a sketch? Does the amp just use easy to find op amps? Thanks, Ted ----- Original Message ----- From: ChrisAtUpw@....... To: psn-l@.............. Sent: Thursday, October 15, 2009 4:13 PM Subject: Re: Torsion Seismometer in a jar In a message dated 15/10/2009 21:27:46 GMT Daylight Time, kevin.mckee@....... writes: There seemed to be some concern that the system would perform poorly or be very noisy. There was some discussion over the LED being a cause for noise. I used various incandescent bulbs, LEDs and sensors, and in some cases, locked the pendulum in a stationary position to test whether the sensor was picking up noise from the LED. In fact, I got a flat line even when the amplifier was maxed out--the LED was significantly quieter than other light sources. Hi Kevin, You seem to be experiencing apparatus problems. Ordinary LEDs are much more noisy than superbright or IR LEDs. Both vary in light output by about x5 between 0 and 100 C. The is a HUGE variation. They are both more noisy than a filament bulb driven from a regulated voltage source. Your flat line response was probably due to low gain. You should be able to pick up microseisms all the time. You can build a very good detector using two large area Si photocells BPW34 connected to a differential amplifier. I get a noise level of about 14 nano metres. You can't get adequate stability with a single detector or with a LED which is not temperature compensated. Phototransistors are extremely noisy compared to photodiodes. You can get very fine Nichrome wire which makes a good suspension. Alternatively, you can use a single glass or carbon filament. Regards, Chris Chapman __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Torsion Seismometer in a jar From: ChrisAtUpw@....... Date: Thu, 15 Oct 2009 22:12:32 EDT In a message dated 16/10/2009, gmvoeth@........... writes: If you used a current source to keep a steady 10ma or 20 ma to the LED would that not be adequate stability for the light output also ? Hi Geoff, No chance. The photo output at a constant current depends on the junction temperature. Regards, Chris Chapman
In a message dated 16/10/2009, gmvoeth@........... writes:
If you=20 used a current source to keep a steady
10ma or 20 ma to the LED would= that=20 not be
adequate stability for the light output also=20 ?
Hi Geoff,
 
    No chance. The photo output at a constant cur= rent=20 depends on the junction temperature.
 
    Regards,
 
    Chris Chapman
Subject: Re: Torsion Seismometer in a jar From: =?ISO-8859-1?Q?J=F3n_Fr=EDmann?= jonfr@......... Date: Fri, 16 Oct 2009 04:04:54 +0000 Hi, Is is possible to edit this design so it doesn't use glass jar and other weak material ? Regards, J=F3n Fr=EDmann. On fim, 2009-10-15 at 16:27 -0400, kevin.mckee@....... wrote: > Hi - > I just joined this e-mail list, and noticed some of the discussion about = the seismometer project I posted at http://tinkeringcaveman.googlepages.com= /home >=20 > There seemed to be some concern that the system would perform poorly or b= e very noisy. There was some discussion over the LED being a cause for nois= e. I performed a number of tests before I completed the seismometer (severa= l years ago now) to satisfy my own concerns in that regard. I used various = incandescent bulbs, LEDs and sensors, and in some cases, locked the pendulu= m in a stationary position to test whether the sensor was picking up noise = from the LED. In fact, I got a flat line even when the amplifier was maxed = out--the LED was significantly quieter than other light sources.=20 >=20 > I've actually found the two devices that I've built (facing orthogonally)= to be very sensitive. I've put together a rough distance-magnitude thresh= old detection plot that I can forward to anyone who is interested. The weak= est quake I've detected is a magnitude 2.0, about 0.05 degrees (about 3 mil= es) away. The common phases are easily picked out of the signal, depending= on the quake origin.=20 >=20 > The larger factor in the devices' sensitivity is that I mounted them on a= basement slab under the stairs to my front porch, which means that they d= etects the comings and goings of my family too (I sometimes used this fact = to check up on my daughters' returns from dates). >=20 > I believe that I am detecting microseismic background with the instrument= too, rather than air currents.=20 >=20 > Regarding the fact that the sensor is a displacement sensor vice a veloci= ty sensor--I don't see that as a problem. As with a capacitive /radio frequ= ency force-balance sensor, electronic filters and amplifiers can be used to= translate the signal into a velocity response, if that is what is desired.= In fact using the appropriate filter amplifier combination gets around any= concerns like those expressed about the resolution of the optical sensing = devices--electronic integration works very well for that. >=20 >=20 > Kevin McKee, Burke, VA > __________________________________________________________ >=20 > Public Seismic Network Mailing List (PSN-L) >=20 > To leave this list email PSN-L-REQUEST@.............. with=20 > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Digest from 10/15/2009 00:01:59 From: kevin.mckee@....... Date: Fri, 16 Oct 2009 5:21:13 -0400 Perhaps one or both of my postings weren't clear. The devices rest on a basement slab in a conditioned space. They are enclosed by a thick Styrofoam box which significantly reduces air currents. These two factors reduce the temperature variation of the instruments, although I don't doubt there could be a couple of degrees variation over the course of long periods relative to the period of the damped pendulum/filter combinations. Because that temperature varies over relatively long times, however, I judge that it is trivial after considering that the ac-coupled integrator suppresses signals longer than about 20 seconds. Also, the instruments use glass fibers for the torsion fiber and glass jars for the structural supports in part to reduce the effects of thermal contraction and expansion. Glass has a significantly lower thermal expansion coefficient than any of the metal pendulums used for the Lehman instruments of which I am aware, for example. Moreover, the dimension of the expansion is orthogonal to the directional sensitivity of the instrument; I hoped that this would further reduce sensitivity to thermal variation. I recognize that this instrument is not a lab quality instrument, but for something that can be built so cheaply and easily by anyone without a lot of technical or machining skills it's a very useful device. I've detected at least 120 earthquakes from all over the world with it. Why discourage folks out there who don't have the skills or $ to build a Porsche when a Ford will get the job done, while spreading the fun of doing science? Kevin McKee, burke, VA ---- psn-l-digest-request@.............. wrote: ============= ..------ ------ ------ ------ ------ ------ ------ ------ ------ ------. | Message 1 | '------ ------ ------ ------ ------ ------ ------ ------ ------ ------' Subject: Torsion Seismometer in a jar From: Date: Thu, 15 Oct 2009 16:27:19 -0400 Hi - I just joined this e-mail list, and noticed some of the discussion about the seismometer project I posted at http://tinkeringcaveman.googlepages.com/home There seemed to be some concern that the system would perform poorly or be very noisy. There was some discussion over the LED being a cause for noise. I performed a number of tests before I completed the seismometer (several years ago now) to satisfy my own concerns in that regard. I used various incandescent bulbs, LEDs and sensors, and in some cases, locked the pendulum in a stationary position to test whether the sensor was picking up noise from the LED. In fact, I got a flat line even when the amplifier was maxed out--the LED was significantly quieter than other light sources. I've actually found the two devices that I've built (facing orthogonally) to be very sensitive. I've put together a rough distance-magnitude threshold detection plot that I can forward to anyone who is interested. The weakest quake I've detected is a magnitude 2.0, about 0.05 degrees (about 3 miles) away. The common phases are easily picked out of the signal, depending on the quake origin. The larger factor in the devices' sensitivity is that I mounted them on a basement slab under the stairs to my front porch, which means that they detects the comings and goings of my family too (I sometimes used this fact to check up on my daughters' returns from dates). I believe that I am detecting microseismic background with the instrument too, rather than air currents. Regarding the fact that the sensor is a displacement sensor vice a velocity sensor--I don't see that as a problem. As with a capacitive /radio frequency force-balance sensor, electronic filters and amplifiers can be used to translate the signal into a velocity response, if that is what is desired. In fact using the appropriate filter amplifier combination gets around any concerns like those expressed about the resolution of the optical sensing devices--electronic integration works very well for that. Kevin McKee, Burke, VA ..------ ------ ------ ------ ------ ------ ------ ------ ------ ------. | Message 2 | '------ ------ ------ ------ ------ ------ ------ ------ ------ ------' Subject: Re: Torsion Seismometer in a jar From: ChrisAtUpw@....... Date: Thu, 15 Oct 2009 18:13:04 EDT -------------------------------1255644784 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit In a message dated 15/10/2009 21:27:46 GMT Daylight Time, kevin.mckee@....... writes: There seemed to be some concern that the system would perform poorly or be very noisy. There was some discussion over the LED being a cause for noise. I used various incandescent bulbs, LEDs and sensors, and in some cases, locked the pendulum in a stationary position to test whether the sensor was picking up noise from the LED. In fact, I got a flat line even when the amplifier was maxed out--the LED was significantly quieter than other light sources. Hi Kevin, You seem to be experiencing apparatus problems. Ordinary LEDs are much more noisy than superbright or IR LEDs. Both vary in light output by about x5 between 0 and 100 C. The is a HUGE variation. They are both more noisy than a filament bulb driven from a regulated voltage source. Your flat line response was probably due to low gain. You should be able to pick up microseisms all the time. You can build a very good detector using two large area Si photocells BPW34 connected to a differential amplifier. I get a noise level of about 14 nano metres. You can't get adequate stability with a single detector or with a LED which is not temperature compensated. Phototransistors are extremely noisy compared to photodiodes. You can get very fine Nichrome wire which makes a good suspension. Alternatively, you can use a single glass or carbon filament. Regards, Chris Chapman -------------------------------1255644784 Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable
In a message dated 15/10/2009 21:27:46 GMT Daylight Time,=20 kevin.mckee@....... writes:
There=20 seemed to be some concern that the system would perform poorly or be ver= y=20 noisy. There was some discussion over the LED being a cause for noise.= I used=20 various incandescent bulbs, LEDs and sensors, and in some cases, locked= the=20 pendulum in a stationary position to test whether the sensor was picking= up=20 noise from the LED. In fact, I got a flat line even when the amplifier= was=20 maxed out--the LED was significantly quieter than other light sources.= =20
Hi Kevin,
 
    You seem to be experiencing apparatus problem= s.=20 Ordinary LEDs are much more noisy than superbright or IR LEDs. Both vary= in=20 light output by about x5 between 0 and 100 C. The is a HUGE variation. The= y are=20 both more noisy than a filament bulb driven from a regulated voltage sourc= e.=20 Your flat line response was probably due to low gain. You should be able= to pick=20 up microseisms all the time.
    You can build a very good detector using two= large=20 area Si photocells BPW34 connected to a differential amplifier. I get a no= ise=20 level of about 14 nano metres. You can't get adequate stability with a sin= gle=20 detector or with a LED which is not temperature compensated. Phototransist= ors=20 are extremely noisy compared to photodiodes. You can get very fine Nichrom= e wire=20 which makes a good suspension. Alternatively, you can use a single gl= ass or=20 carbon filament.
 
    Regards,
 
    Chris Chapman
 
    
-------------------------------1255644784-- ..------ ------ ------ ------ ------ ------ ------ ------ ------ ------. | Message 3 | '------ ------ ------ ------ ------ ------ ------ ------ ------ ------' Subject: Re: Torsion Seismometer in a jar From: "tchannel" Date: Thu, 15 Oct 2009 17:18:47 -0600 This is a multi-part message in MIME format. ------=_NextPart_000_000A_01CA4DBB.8E711840 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Hi Chris, the two large area Si photocells BPW34 connected to a = differential amplifier, sound like something I would like to try. Could = you help me with a simple schematic of this, even a sketch? Does the = amp just use easy to find op amps? Thanks, Ted ----- Original Message -----=20 From: ChrisAtUpw@.......... To: psn-l@................. Sent: Thursday, October 15, 2009 4:13 PM Subject: Re: Torsion Seismometer in a jar In a message dated 15/10/2009 21:27:46 GMT Daylight Time, = kevin.mckee@....... writes: There seemed to be some concern that the system would perform poorly = or be very noisy. There was some discussion over the LED being a cause = for noise. I used various incandescent bulbs, LEDs and sensors, and in = some cases, locked the pendulum in a stationary position to test whether = the sensor was picking up noise from the LED. In fact, I got a flat line = even when the amplifier was maxed out--the LED was significantly quieter = than other light sources.=20 Hi Kevin, You seem to be experiencing apparatus problems. Ordinary LEDs are = much more noisy than superbright or IR LEDs. Both vary in light output = by about x5 between 0 and 100 C. The is a HUGE variation. They are both = more noisy than a filament bulb driven from a regulated voltage source. = Your flat line response was probably due to low gain. You should be able = to pick up microseisms all the time. You can build a very good detector using two large area Si = photocells BPW34 connected to a differential amplifier. I get a noise = level of about 14 nano metres. You can't get adequate stability with a = single detector or with a LED which is not temperature compensated. = Phototransistors are extremely noisy compared to photodiodes. You can = get very fine Nichrome wire which makes a good suspension. = Alternatively, you can use a single glass or carbon filament.=20 Regards, Chris Chapman ------=_NextPart_000_000A_01CA4DBB.8E711840 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Hi Chris,  the two large area Si photocells BPW34 connected to = a=20 differential amplifier, sound like something I would like to try.  = Could=20 you help me with a simple schematic of this, even a sketch?   = Does the=20 amp just use easy to find op amps?
 
Thanks, Ted
----- Original Message -----
From:=20 ChrisAtUpw@.......
Sent: Thursday, October 15, = 2009 4:13=20 PM
Subject: Re: Torsion = Seismometer in a=20 jar

In a message dated 15/10/2009 21:27:46 GMT Daylight Time, kevin.mckee@....... = writes:
There=20 seemed to be some concern that the system would perform poorly or be = very=20 noisy. There was some discussion over the LED being a cause for = noise. I=20 used various incandescent bulbs, LEDs and sensors, and in some = cases, locked=20 the pendulum in a stationary position to test whether the sensor was = picking=20 up noise from the LED. In fact, I got a flat line even when the = amplifier=20 was maxed out--the LED was significantly quieter than other light = sources.=20
Hi Kevin,
 
    You seem to be experiencing apparatus = problems.=20 Ordinary LEDs are much more noisy than superbright or IR LEDs. Both = vary in=20 light output by about x5 between 0 and 100 C. The is a HUGE variation. = They=20 are both more noisy than a filament bulb driven from a regulated = voltage=20 source. Your flat line response was probably due to low gain. You = should be=20 able to pick up microseisms all the time.
    You can build a very good detector using = two=20 large area Si photocells BPW34 connected to a differential amplifier. = I get a=20 noise level of about 14 nano metres. You can't get adequate stability = with a=20 single detector or with a LED which is not temperature compensated.=20 Phototransistors are extremely noisy compared to photodiodes. You can = get very=20 fine Nichrome wire which makes a good suspension. Alternatively, = you can=20 use a single glass or carbon filament.
 
    Regards,
 
    Chris Chapman
 
    
------=_NextPart_000_000A_01CA4DBB.8E711840-- ..------ ------ ------ ------ ------ ------ ------ ------ ------ ------. | Message 4 | '------ ------ ------ ------ ------ ------ ------ ------ ------ ------' Subject: Re: Torsion Seismometer in a jar From: ChrisAtUpw@....... Date: Thu, 15 Oct 2009 21:49:17 EDT -------------------------------1255657757 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit In a message dated 16/10/2009, tchannel@............ writes: Hi Chris, the two large area Si photocells BPW34 connected to a differential amplifier, sound like something I would like to try. Could you help me with a simple schematic of this, even a sketch? Does the amp just use easy to find op amps? Thanks, Ted Hi Ted, Check out the notes and the circuit at _http://jclahr.com/science/psn/chapman/photo_detect/index.html_ (http://jclahr.com/science/psn/chapman/photo_detect/index.html) This circuit works fine. You need the INA118 or similar to get the very high CMRR common mode rejection ratio. You may need to alter filter values to suit your application. The photocells drive current into the opamps, so they run at 0V and there is no leakage current. I usually use a miniature filament bulb driven from a stabilised voltage and a lens to give a ~parallel light beam. You can use an IR LED if you provide an auxiliary Si photodiode and a feedback amplifier to stabilise the photo output. Otherwise it drifts all over the place. I use two small razor blades for the sides of the shutter, painted matt black, but with clean edges. They move just clear of the surface of the photocells. I measured the noise level at about 14 nano metres. There is inevitably some heat associated with the bulb. I suggest placing the bulb in a separate housing on top of the sensor. You under run the bulb voltage supply to give ~infinite life. Regards, Chris Chapman -------------------------------1255657757 Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable
In a message dated 16/10/2009, tchannel@............ writes:
Hi Chris,  the two large area Si photocells BPW34 connected to= a=20 differential amplifier, sound like something I would like to try. = Could=20 you help me with a simple schematic of this, even a sketch?  = Does=20 the amp just use easy to find op amps?
 
Thanks, Ted
Hi Ted,
 
    Check out the notes and the circuit at  = htt= p://jclahr.com/science/psn/chapman/photo_detect/index.html
    This circuit works fine. You need the INA118= or=20 similar to get the very high CMRR common mode rejection ratio. You may nee= d to=20 alter filter values to suit your application. The photocells drive current= into=20 the opamps, so they run at 0V and there is no leakage current. I usually= use=20 a miniature filament bulb driven from a stabilised voltage and a lens= to=20 give a ~parallel light beam. You can use an IR LED if you provide an auxil= iary=20 Si photodiode and a feedback amplifier to stabilise the photo output. Othe= rwise=20 it drifts all over the place. I use two small razor blades for the sides= of the=20 shutter, painted matt black, but with clean edges. They move just clear of= the=20 surface of the photocells.  I measured the noise level at about 14 na= no=20 metres. There is inevitably some heat associated with the bulb. I suggest= =20 placing the bulb in a separate housing on top of the sensor. You under run= the=20 bulb voltage supply to give ~infinite life.
 
    Regards,
 
    Chris Chapman
-------------------------------1255657757-- ..------ ------ ------ ------ ------ ------ ------ ------ ------ ------. | Message 5 | '------ ------ ------ ------ ------ ------ ------ ------ ------ ------' Subject: Re: Torsion Seismometer in a jar From: "Geoffrey" Date: Thu, 15 Oct 2009 19:07:15 -0700 If you used a current source to keep a steady 10ma or 20 ma to the LED would that not be adequate stability for the light output also ? ----- Original Message ----- From: "tchannel" To: Sent: Thursday, October 15, 2009 4:18 PM Subject: Re: Torsion Seismometer in a jar Hi Chris, the two large area Si photocells BPW34 connected to a differential amplifier, sound like something I would like to try. Could you help me with a simple schematic of this, even a sketch? Does the amp just use easy to find op amps? Thanks, Ted ----- Original Message ----- From: ChrisAtUpw@....... To: psn-l@.............. Sent: Thursday, October 15, 2009 4:13 PM Subject: Re: Torsion Seismometer in a jar In a message dated 15/10/2009 21:27:46 GMT Daylight Time, kevin.mckee@....... writes: There seemed to be some concern that the system would perform poorly or be very noisy. There was some discussion over the LED being a cause for noise. I used various incandescent bulbs, LEDs and sensors, and in some cases, locked the pendulum in a stationary position to test whether the sensor was picking up noise from the LED. In fact, I got a flat line even when the amplifier was maxed out--the LED was significantly quieter than other light sources. Hi Kevin, You seem to be experiencing apparatus problems. Ordinary LEDs are much more noisy than superbright or IR LEDs. Both vary in light output by about x5 between 0 and 100 C. The is a HUGE variation. They are both more noisy than a filament bulb driven from a regulated voltage source. Your flat line response was probably due to low gain. You should be able to pick up microseisms all the time. You can build a very good detector using two large area Si photocells BPW34 connected to a differential amplifier. I get a noise level of about 14 nano metres. You can't get adequate stability with a single detector or with a LED which is not temperature compensated. Phototransistors are extremely noisy compared to photodiodes. You can get very fine Nichrome wire which makes a good suspension. Alternatively, you can use a single glass or carbon filament. Regards, Chris Chapman ..------ ------ ------ ------ ------ ------ ------ ------ ------ ------. | Message 6 | '------ ------ ------ ------ ------ ------ ------ ------ ------ ------' Subject: Re: Torsion Seismometer in a jar From: ChrisAtUpw@....... Date: Thu, 15 Oct 2009 22:12:32 EDT -------------------------------1255659152 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit In a message dated 16/10/2009, gmvoeth@........... writes: If you used a current source to keep a steady 10ma or 20 ma to the LED would that not be adequate stability for the light output also ? Hi Geoff, No chance. The photo output at a constant current depends on the junction temperature. Regards, Chris Chapman -------------------------------1255659152 Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable
In a message dated 16/10/2009, gmvoeth@........... writes:
If you=20 used a current source to keep a steady
10ma or 20 ma to the LED would= that=20 not be
adequate stability for the light output also=20 ?
Hi Geoff,
 
    No chance. The photo output at a constant cur= rent=20 depends on the junction temperature.
 
    Regards,
 
    Chris Chapman
-------------------------------1255659152-- ..------ ------ ------ ------ ------ ------ ------ ------ ------ ------. | Message 7 | '------ ------ ------ ------ ------ ------ ------ ------ ------ ------' Subject: Re: Torsion Seismometer in a jar From: =?ISO-8859-1?Q?J=F3n_Fr=EDmann?= Date: Fri, 16 Oct 2009 04:04:54 +0000 Hi, Is is possible to edit this design so it doesn't use glass jar and other weak material ? Regards, J=F3n Fr=EDmann. On fim, 2009-10-15 at 16:27 -0400, kevin.mckee@....... wrote: > Hi - > I just joined this e-mail list, and noticed some of the discussion about = the seismometer project I posted at http://tinkeringcaveman.googlepages.com= /home >=20 > There seemed to be some concern that the system would perform poorly or b= e very noisy. There was some discussion over the LED being a cause for nois= e. I performed a number of tests before I completed the seismometer (severa= l years ago now) to satisfy my own concerns in that regard. I used various = incandescent bulbs, LEDs and sensors, and in some cases, locked the pendulu= m in a stationary position to test whether the sensor was picking up noise = from the LED. In fact, I got a flat line even when the amplifier was maxed = out--the LED was significantly quieter than other light sources.=20 >=20 > I've actually found the two devices that I've built (facing orthogonally)= to be very sensitive. I've put together a rough distance-magnitude thresh= old detection plot that I can forward to anyone who is interested. The weak= est quake I've detected is a magnitude 2.0, about 0.05 degrees (about 3 mil= es) away. The common phases are easily picked out of the signal, depending= on the quake origin.=20 >=20 > The larger factor in the devices' sensitivity is that I mounted them on a= basement slab under the stairs to my front porch, which means that they d= etects the comings and goings of my family too (I sometimes used this fact = to check up on my daughters' returns from dates). >=20 > I believe that I am detecting microseismic background with the instrument= too, rather than air currents.=20 >=20 > Regarding the fact that the sensor is a displacement sensor vice a veloci= ty sensor--I don't see that as a problem. As with a capacitive /radio frequ= ency force-balance sensor, electronic filters and amplifiers can be used to= translate the signal into a velocity response, if that is what is desired.= In fact using the appropriate filter amplifier combination gets around any= concerns like those expressed about the resolution of the optical sensing = devices--electronic integration works very well for that. >=20 >=20 > Kevin McKee, Burke, VA > __________________________________________________________ >=20 > Public Seismic Network Mailing List (PSN-L) >=20 > To leave this list email PSN-L-REQUEST@.............. with=20 > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. __________________________________________________________ Public Seismic Network Mailing List (PSN-L) To leave this list email PSN-L-DIGEST-REQUEST@.............. with the body of the message (first line only): unsubscribe See http://www.seismicnet.com/maillist.html for more information. __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Digest from 10/15/2009 00:01:59 From: "tchannel" tchannel@............ Date: Fri, 16 Oct 2009 06:16:42 -0600 Kevin, I very much like your sensor in a jar. Even the most excepted standards and designs at one time were unique. I try everything I can think of, but must admit I never tried one in a jar. I have used very long vertical spring which understandably would have great thermo expansion issues, but I have not seen any problem using them successfully. I place my sensors in a living area, garage or basement and the temperature is more or less constant. I ran a test in a 55 degree room, using a heater, warmed the room to 75 but could see no effect on the trace. I know the 48" long vertical spring was expanding, but it did not change anything I could see. My normal room temp. changes very little. On the other hand I have seen massive noise with air currents. I too keep these to a minimum. Anyhow, well done on your jar, I want to build one if I can find the time. This hobby, for me, is exciting because of the constant innovations. The fact is, many of these ideas, will not work, some will, but not well, and some will work just fine. Its always fun to see new approaches. Thanks, for sharing, Ted ----- Original Message ----- From: To: Cc: Sent: Friday, October 16, 2009 3:21 AM Subject: Re: Digest from 10/15/2009 00:01:59 > Perhaps one or both of my postings weren't clear. > > The devices rest on a basement slab in a conditioned space. They are > enclosed by a thick Styrofoam box which significantly reduces air > currents. These two factors reduce the temperature variation of the > instruments, although I don't doubt there could be a couple of degrees > variation over the course of long periods relative to the period of the > damped pendulum/filter combinations. Because that temperature varies over > relatively long times, however, I judge that it is trivial after > considering that the ac-coupled integrator suppresses signals longer than > about 20 seconds. > > Also, the instruments use glass fibers for the torsion fiber and glass > jars for the structural supports in part to reduce the effects of thermal > contraction and expansion. Glass has a significantly lower thermal > expansion coefficient than any of the metal pendulums used for the Lehman > instruments of which I am aware, for example. Moreover, the dimension of > the expansion is orthogonal to the directional sensitivity of the > instrument; I hoped that this would further reduce sensitivity to thermal > variation. > > I recognize that this instrument is not a lab quality instrument, but for > something that can be built so cheaply and easily by anyone without a lot > of technical or machining skills it's a very useful device. I've detected > at least 120 earthquakes from all over the world with it. > > Why discourage folks out there who don't have the skills or $ to build a > Porsche when a Ford will get the job done, while spreading the fun of > doing science? > > Kevin McKee, burke, VA > > ---- psn-l-digest-request@.............. wrote: > > ============= > > .------ ------ ------ ------ ------ ------ ------ ------ ------ ------. > | Message 1 | > '------ ------ ------ ------ ------ ------ ------ ------ ------ ------' > Subject: Torsion Seismometer in a jar > From: > Date: Thu, 15 Oct 2009 16:27:19 -0400 > > Hi - > I just joined this e-mail list, and noticed some of the discussion about > the seismometer project I posted at > http://tinkeringcaveman.googlepages.com/home > > There seemed to be some concern that the system would perform poorly or be > very noisy. There was some discussion over the LED being a cause for > noise. I performed a number of tests before I completed the seismometer > (several years ago now) to satisfy my own concerns in that regard. I used > various incandescent bulbs, LEDs and sensors, and in some cases, locked > the pendulum in a stationary position to test whether the sensor was > picking up noise from the LED. In fact, I got a flat line even when the > amplifier was maxed out--the LED was significantly quieter than other > light sources. > > I've actually found the two devices that I've built (facing orthogonally) > to be very sensitive. I've put together a rough distance-magnitude > threshold detection plot that I can forward to anyone who is interested. > The weakest quake I've detected is a magnitude 2.0, about 0.05 degrees > (about 3 miles) away. The common phases are easily picked out of the > signal, depending on the quake origin. > > The larger factor in the devices' sensitivity is that I mounted them on a > basement slab under the stairs to my front porch, which means that they > detects the comings and goings of my family too (I sometimes used this > fact to check up on my daughters' returns from dates). > > I believe that I am detecting microseismic background with the instrument > too, rather than air currents. > > Regarding the fact that the sensor is a displacement sensor vice a > velocity sensor--I don't see that as a problem. As with a capacitive > /radio frequency force-balance sensor, electronic filters and amplifiers > can be used to translate the signal into a velocity response, if that is > what is desired. In fact using the appropriate filter amplifier > combination gets around any concerns like those expressed about the > resolution of the optical sensing devices--electronic integration works > very well for that. > > > Kevin McKee, Burke, VA > > > .------ ------ ------ ------ ------ ------ ------ ------ ------ ------. > | Message 2 | > '------ ------ ------ ------ ------ ------ ------ ------ ------ ------' > Subject: Re: Torsion Seismometer in a jar > From: ChrisAtUpw@....... > Date: Thu, 15 Oct 2009 18:13:04 EDT > > > -------------------------------1255644784 > Content-Type: text/plain; charset="US-ASCII" > Content-Transfer-Encoding: 7bit > > > In a message dated 15/10/2009 21:27:46 GMT Daylight Time, > kevin.mckee@....... writes: > > There seemed to be some concern that the system would perform poorly or > be > very noisy. There was some discussion over the LED being a cause for > noise. I used various incandescent bulbs, LEDs and sensors, and in some > cases, > locked the pendulum in a stationary position to test whether the sensor > was > picking up noise from the LED. In fact, I got a flat line even when the > amplifier was maxed out--the LED was significantly quieter than other > light > sources. > > > > Hi Kevin, > > You seem to be experiencing apparatus problems. Ordinary LEDs are much > more noisy than superbright or IR LEDs. Both vary in light output by > about > x5 between 0 and 100 C. The is a HUGE variation. They are both more noisy > than a filament bulb driven from a regulated voltage source. Your flat > line > response was probably due to low gain. You should be able to pick up > microseisms all the time. > You can build a very good detector using two large area Si photocells > BPW34 connected to a differential amplifier. I get a noise level of about > 14 nano metres. You can't get adequate stability with a single detector > or > with a LED which is not temperature compensated. Phototransistors are > extremely noisy compared to photodiodes. You can get very fine Nichrome > wire > which makes a good suspension. Alternatively, you can use a single glass > or > carbon filament. > > Regards, > > Chris Chapman > > > > -------------------------------1255644784 > Content-Type: text/html; charset="US-ASCII" > Content-Transfer-Encoding: quoted-printable > > > > > > id=3Dr= > ole_body=20 > bottomMargin=3D7 leftMargin=3D7 rightMargin=3D7 topMargin=3D7> id=3Dr= > ole_document=20 > color=3D#000000 size=3D2 face=3DArial> >
>
In a message dated 15/10/2009 21:27:46 GMT Daylight Time,=20 > kevin.mckee@....... writes:
> style=3D"BORDER-LEFT: blue 2px solid; PADDING-LEFT: 5px; MARGIN-LEFT: > 5px"= >> style=3D"BACKGROUND-COLOR: transparent" color=3D#000000 size=3D2 face=3D= > Arial>There=20 > seemed to be some concern that the system would perform poorly or be ver= > y=20 > noisy. There was some discussion over the LED being a cause for noise.= > I used=20 > various incandescent bulbs, LEDs and sensors, and in some cases, locked= > the=20 > pendulum in a stationary position to test whether the sensor was picking= > up=20 > noise from the LED. In fact, I got a flat line even when the amplifier= > was=20 > maxed out--the LED was significantly quieter than other light sources.= > =20 >
>
>
Hi Kevin,
>
 
>
    You seem to be experiencing apparatus > problem= > s.=20 > Ordinary LEDs are much more noisy than superbright or IR LEDs. Both vary= > in=20 > light output by about x5 between 0 and 100 C. The is a HUGE variation. > The= > y are=20 > both more noisy than a filament bulb driven from a regulated voltage > sourc= > e.=20 > Your flat line response was probably due to low gain. You should be able= > to pick=20 > up microseisms all the time.
>
    You can build a very good detector using two= > large=20 > area Si photocells BPW34 connected to a differential amplifier. I get a > no= > ise=20 > level of about 14 nano metres. You can't get adequate stability with a > sin= > gle=20 > detector or with a LED which is not temperature compensated. > Phototransist= > ors=20 > are extremely noisy compared to photodiodes. You can get very fine > Nichrom= > e wire=20 > which makes a good suspension. Alternatively, you can use a single > gl= > ass or=20 > carbon filament.
>
 
>
    Regards,
>
 
>
    Chris Chapman
>
 
>
    
> > -------------------------------1255644784-- > > > .------ ------ ------ ------ ------ ------ ------ ------ ------ ------. > | Message 3 | > '------ ------ ------ ------ ------ ------ ------ ------ ------ ------' > Subject: Re: Torsion Seismometer in a jar > From: "tchannel" > Date: Thu, 15 Oct 2009 17:18:47 -0600 > > This is a multi-part message in MIME format. > > ------=_NextPart_000_000A_01CA4DBB.8E711840 > Content-Type: text/plain; > charset="iso-8859-1" > Content-Transfer-Encoding: quoted-printable > > Hi Chris, the two large area Si photocells BPW34 connected to a = > differential amplifier, sound like something I would like to try. Could = > you help me with a simple schematic of this, even a sketch? Does the = > amp just use easy to find op amps? > > Thanks, Ted > ----- Original Message -----=20 > From: ChrisAtUpw@.......... > To: psn-l@................. > Sent: Thursday, October 15, 2009 4:13 PM > Subject: Re: Torsion Seismometer in a jar > > > In a message dated 15/10/2009 21:27:46 GMT Daylight Time, = > kevin.mckee@....... writes: > There seemed to be some concern that the system would perform poorly = > or be very noisy. There was some discussion over the LED being a cause = > for noise. I used various incandescent bulbs, LEDs and sensors, and in = > some cases, locked the pendulum in a stationary position to test whether = > the sensor was picking up noise from the LED. In fact, I got a flat line = > even when the amplifier was maxed out--the LED was significantly quieter = > than other light sources.=20 > > Hi Kevin, > > You seem to be experiencing apparatus problems. Ordinary LEDs are = > much more noisy than superbright or IR LEDs. Both vary in light output = > by about x5 between 0 and 100 C. The is a HUGE variation. They are both = > more noisy than a filament bulb driven from a regulated voltage source. = > Your flat line response was probably due to low gain. You should be able = > to pick up microseisms all the time. > You can build a very good detector using two large area Si = > photocells BPW34 connected to a differential amplifier. I get a noise = > level of about 14 nano metres. You can't get adequate stability with a = > single detector or with a LED which is not temperature compensated. = > Phototransistors are extremely noisy compared to photodiodes. You can = > get very fine Nichrome wire which makes a good suspension. = > Alternatively, you can use a single glass or carbon filament.=20 > > Regards, > > Chris Chapman > > > ------=_NextPart_000_000A_01CA4DBB.8E711840 > Content-Type: text/html; > charset="iso-8859-1" > Content-Transfer-Encoding: quoted-printable > > > > http-equiv=3DContent-Type> > > > > id=3Drole_body=20 > bottomMargin=3D7 leftMargin=3D7 rightMargin=3D7 topMargin=3D7 = > bgColor=3D#ffffff> >
Hi Chris,  the two large area Si photocells BPW34 connected to = > a=20 > differential amplifier, sound like something I would like to try.  = > Could=20 > you help me with a simple schematic of this, even a sketch?   = > Does the=20 > amp just use easy to find op amps?
>
 
>
Thanks, Ted
> style=3D"BORDER-LEFT: #000000 2px solid; PADDING-LEFT: 5px; = > PADDING-RIGHT: 0px; MARGIN-LEFT: 5px; MARGIN-RIGHT: 0px"=20 > dir=3Dltr> >
----- Original Message -----
> style=3D"FONT: 10pt arial; BACKGROUND: #e4e4e4; font-color: = > black">From:=20 > href=3D"mailto:ChrisAtUpw@.......">ChrisAtUpw@....... > >
Sent: Thursday, October 15, = > 2009 4:13=20 > PM
>
Subject: Re: Torsion = > Seismometer in a=20 > jar
>

face=3DArial> >
>
In a message dated 15/10/2009 21:27:46 GMT Daylight Time, href=3D"mailto:kevin.mckee@.......">kevin.mckee@....... = > writes:
> style=3D"BORDER-LEFT: blue 2px solid; PADDING-LEFT: 5px; MARGIN-LEFT: = > 5px"> style=3D"BACKGROUND-COLOR: transparent" color=3D#000000 size=3D2 = > face=3DArial>There=20 > seemed to be some concern that the system would perform poorly or be = > very=20 > noisy. There was some discussion over the LED being a cause for = > noise. I=20 > used various incandescent bulbs, LEDs and sensors, and in some = > cases, locked=20 > the pendulum in a stationary position to test whether the sensor was = > picking=20 > up noise from the LED. In fact, I got a flat line even when the = > amplifier=20 > was maxed out--the LED was significantly quieter than other light = > sources.=20 >
>
>
Hi Kevin,
>
 
>
    You seem to be experiencing apparatus = > problems.=20 > Ordinary LEDs are much more noisy than superbright or IR LEDs. Both = > vary in=20 > light output by about x5 between 0 and 100 C. The is a HUGE variation. = > They=20 > are both more noisy than a filament bulb driven from a regulated = > voltage=20 > source. Your flat line response was probably due to low gain. You = > should be=20 > able to pick up microseisms all the time.
>
    You can build a very good detector using = > two=20 > large area Si photocells BPW34 connected to a differential amplifier. = > I get a=20 > noise level of about 14 nano metres. You can't get adequate stability = > with a=20 > single detector or with a LED which is not temperature compensated.=20 > Phototransistors are extremely noisy compared to photodiodes. You can = > get very=20 > fine Nichrome wire which makes a good suspension. Alternatively, = > you can=20 > use a single glass or carbon filament.
>
 
>
    Regards,
>
 
>
    Chris Chapman
>
 
>
    
> > ------=_NextPart_000_000A_01CA4DBB.8E711840-- > > > > .------ ------ ------ ------ ------ ------ ------ ------ ------ ------. > | Message 4 | > '------ ------ ------ ------ ------ ------ ------ ------ ------ ------' > Subject: Re: Torsion Seismometer in a jar > From: ChrisAtUpw@....... > Date: Thu, 15 Oct 2009 21:49:17 EDT > > > -------------------------------1255657757 > Content-Type: text/plain; charset="US-ASCII" > Content-Transfer-Encoding: 7bit > > > In a message dated 16/10/2009, tchannel@............ writes: > > Hi Chris, the two large area Si photocells BPW34 connected to a > differential amplifier, sound like something I would like to try. Could > you help me > with a simple schematic of this, even a sketch? Does the amp just use > easy to find op amps? > > Thanks, Ted > > > > Hi Ted, > > Check out the notes and the circuit at > _http://jclahr.com/science/psn/chapman/photo_detect/index.html_ > (http://jclahr.com/science/psn/chapman/photo_detect/index.html) > This circuit works fine. You need the INA118 or similar to get the > very high CMRR common mode rejection ratio. You may need to alter filter > values to suit your application. The photocells drive current into the > opamps, > so they run at 0V and there is no leakage current. I usually use a > miniature > filament bulb driven from a stabilised voltage and a lens to give a > ~parallel light beam. You can use an IR LED if you provide an auxiliary > Si > photodiode and a feedback amplifier to stabilise the photo output. > Otherwise it > drifts all over the place. I use two small razor blades for the sides of > the > shutter, painted matt black, but with clean edges. They move just clear of > the surface of the photocells. I measured the noise level at about 14 > nano > metres. There is inevitably some heat associated with the bulb. I suggest > placing the bulb in a separate housing on top of the sensor. You under run > the bulb voltage supply to give ~infinite life. > > Regards, > > Chris Chapman > > -------------------------------1255657757 > Content-Type: text/html; charset="US-ASCII" > Content-Transfer-Encoding: quoted-printable > > > > > > id=3Dr= > ole_body=20 > bottomMargin=3D7 leftMargin=3D7 rightMargin=3D7 topMargin=3D7> id=3Dr= > ole_document=20 > color=3D#000000 size=3D2 face=3DArial> >
>
In a message dated 16/10/2009, tchannel@............ writes:
> style=3D"BORDER-LEFT: blue 2px solid; PADDING-LEFT: 5px; MARGIN-LEFT: > 5px"= >> style=3D"BACKGROUND-COLOR: transparent" color=3D#000000 size=3D2 face=3D= > Arial> >
Hi Chris,  the two large area Si photocells BPW34 connected to= > a=20 > differential amplifier, sound like something I would like to try. = > Could=20 > you help me with a simple schematic of this, even a sketch?  = > Does=20 > the amp just use easy to find op amps?
>
 
>
Thanks, Ted
>
>
Hi Ted,
>
 
>
    Check out the notes and the circuit at >  = > href=3D"http://jclahr.com/science/psn/chapman/photo_detect/index.html">htt= > p://jclahr.com/science/psn/chapman/photo_detect/index.html
>
    This circuit works fine. You need the INA118= > or=20 > similar to get the very high CMRR common mode rejection ratio. You may > nee= > d to=20 > alter filter values to suit your application. The photocells drive > current= > into=20 > the opamps, so they run at 0V and there is no leakage current. I usually= > use=20 > a miniature filament bulb driven from a stabilised voltage and a > lens= > to=20 > give a ~parallel light beam. You can use an IR LED if you provide an > auxil= > iary=20 > Si photodiode and a feedback amplifier to stabilise the photo output. > Othe= > rwise=20 > it drifts all over the place. I use two small razor blades for the sides= > of the=20 > shutter, painted matt black, but with clean edges. They move just clear > of= > the=20 > surface of the photocells.  I measured the noise level at about 14 > na= > no=20 > metres. There is inevitably some heat associated with the bulb. I suggest= > =20 > placing the bulb in a separate housing on top of the sensor. You under > run= > the=20 > bulb voltage supply to give ~infinite life.
>
 
>
    Regards,
>
 
>
    Chris Chapman
> > -------------------------------1255657757-- > > > .------ ------ ------ ------ ------ ------ ------ ------ ------ ------. > | Message 5 | > '------ ------ ------ ------ ------ ------ ------ ------ ------ ------' > Subject: Re: Torsion Seismometer in a jar > From: "Geoffrey" > Date: Thu, 15 Oct 2009 19:07:15 -0700 > > If you used a current source to keep a steady > 10ma or 20 ma to the LED would that not be > adequate stability for the light output also ? > > > ----- Original Message ----- > From: "tchannel" > To: > Sent: Thursday, October 15, 2009 4:18 PM > Subject: Re: Torsion Seismometer in a jar > > > Hi Chris, the two large area Si photocells BPW34 connected to a > differential amplifier, sound like something I would like to try. > Could you help me with a simple schematic of this, even a sketch? Does > the amp just use easy to find op amps? > > Thanks, Ted > ----- Original Message ----- > From: ChrisAtUpw@....... > To: psn-l@.............. > Sent: Thursday, October 15, 2009 4:13 PM > Subject: Re: Torsion Seismometer in a jar > > > In a message dated 15/10/2009 21:27:46 GMT Daylight Time, > kevin.mckee@....... writes: > There seemed to be some concern that the system would perform poorly or > be very noisy. There was some discussion over the LED > being a cause for noise. I used various incandescent bulbs, LEDs and > sensors, and in some cases, locked the pendulum in a stationary > position to test whether the sensor was picking up noise from the LED. In > fact, I got a flat line even when the amplifier was maxed > out--the LED was significantly quieter than other light sources. > > Hi Kevin, > > You seem to be experiencing apparatus problems. Ordinary LEDs are > much more noisy than superbright or IR LEDs. Both vary in > light output by about x5 between 0 and 100 C. The is a HUGE variation. > They are both more noisy than a filament bulb driven from a > regulated voltage source. Your flat line response was probably due to low > gain. You should be able to pick up microseisms all the > time. > You can build a very good detector using two large area Si photocells > BPW34 connected to a differential amplifier. I get a > noise level of about 14 nano metres. You can't get adequate stability with > a single detector or with a LED which is not temperature > compensated. Phototransistors are extremely noisy compared to photodiodes. > You can get very fine Nichrome wire which makes a good > suspension. Alternatively, you can use a single glass or carbon filament. > > Regards, > > Chris Chapman > > > > > .------ ------ ------ ------ ------ ------ ------ ------ ------ ------. > | Message 6 | > '------ ------ ------ ------ ------ ------ ------ ------ ------ ------' > Subject: Re: Torsion Seismometer in a jar > From: ChrisAtUpw@....... > Date: Thu, 15 Oct 2009 22:12:32 EDT > > > -------------------------------1255659152 > Content-Type: text/plain; charset="US-ASCII" > Content-Transfer-Encoding: 7bit > > > In a message dated 16/10/2009, gmvoeth@........... writes: > > If you used a current source to keep a steady > 10ma or 20 ma to the LED would that not be > adequate stability for the light output also ? > > > > Hi Geoff, > > No chance. The photo output at a constant current depends on the > junction temperature. > > Regards, > > Chris Chapman > > -------------------------------1255659152 > Content-Type: text/html; charset="US-ASCII" > Content-Transfer-Encoding: quoted-printable > > > > > > id=3Dr= > ole_body=20 > bottomMargin=3D7 leftMargin=3D7 rightMargin=3D7 topMargin=3D7> id=3Dr= > ole_document=20 > color=3D#000000 size=3D2 face=3DArial> >
>
In a message dated 16/10/2009, gmvoeth@........... writes:
> style=3D"BORDER-LEFT: blue 2px solid; PADDING-LEFT: 5px; MARGIN-LEFT: > 5px"= >> style=3D"BACKGROUND-COLOR: transparent" color=3D#000000 size=3D2 face=3D= > Arial>If you=20 > used a current source to keep a steady
10ma or 20 ma to the LED would= > that=20 > not be
adequate stability for the light output also=20 > ?
>
>
Hi Geoff,
>
 
>
    No chance. The photo output at a constant > cur= > rent=20 > depends on the junction temperature.
>
 
>
    Regards,
>
 
>
    Chris Chapman
> > -------------------------------1255659152-- > > > .------ ------ ------ ------ ------ ------ ------ ------ ------ ------. > | Message 7 | > '------ ------ ------ ------ ------ ------ ------ ------ ------ ------' > Subject: Re: Torsion Seismometer in a jar > From: =?ISO-8859-1?Q?J=F3n_Fr=EDmann?= > Date: Fri, 16 Oct 2009 04:04:54 +0000 > > Hi, > > Is is possible to edit this design so it doesn't use glass jar and other > weak material ? > > Regards, > J=F3n Fr=EDmann. > > On fim, 2009-10-15 at 16:27 -0400, kevin.mckee@....... wrote: >> Hi - >> I just joined this e-mail list, and noticed some of the discussion about >> = > the seismometer project I posted at > http://tinkeringcaveman.googlepages.com= > /home >>=20 >> There seemed to be some concern that the system would perform poorly or >> b= > e very noisy. There was some discussion over the LED being a cause for > nois= > e. I performed a number of tests before I completed the seismometer > (severa= > l years ago now) to satisfy my own concerns in that regard. I used various > = > incandescent bulbs, LEDs and sensors, and in some cases, locked the > pendulu= > m in a stationary position to test whether the sensor was picking up noise > = > from the LED. In fact, I got a flat line even when the amplifier was maxed > = > out--the LED was significantly quieter than other light sources.=20 >>=20 >> I've actually found the two devices that I've built (facing >> orthogonally)= > to be very sensitive. I've put together a rough distance-magnitude > thresh= > old detection plot that I can forward to anyone who is interested. The > weak= > est quake I've detected is a magnitude 2.0, about 0.05 degrees (about 3 > mil= > es) away. The common phases are easily picked out of the signal, > depending= > on the quake origin.=20 >>=20 >> The larger factor in the devices' sensitivity is that I mounted them on >> a= > basement slab under the stairs to my front porch, which means that they > d= > etects the comings and goings of my family too (I sometimes used this fact > = > to check up on my daughters' returns from dates). >>=20 >> I believe that I am detecting microseismic background with the >> instrument= > too, rather than air currents.=20 >>=20 >> Regarding the fact that the sensor is a displacement sensor vice a >> veloci= > ty sensor--I don't see that as a problem. As with a capacitive /radio > frequ= > ency force-balance sensor, electronic filters and amplifiers can be used > to= > translate the signal into a velocity response, if that is what is > desired.= > In fact using the appropriate filter amplifier combination gets around > any= > concerns like those expressed about the resolution of the optical sensing > = > devices--electronic integration works very well for that. >>=20 >>=20 >> Kevin McKee, Burke, VA >> __________________________________________________________ >>=20 >> Public Seismic Network Mailing List (PSN-L) >>=20 >> To leave this list email PSN-L-REQUEST@.............. with=20 >> the body of the message (first line only): unsubscribe >> See http://www.seismicnet.com/maillist.html for more information. > > > > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-DIGEST-REQUEST@.............. with > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Background Noise From: "Gary Lindgren" gel@................. Date: Fri, 16 Oct 2009 20:02:14 -0700 After the big quakes in the South Pacific a couple weeks ago it seems to me that the background noise was very high after the events and stayed that way for many days. I had to lower the gain on my Lehman otherwise the display would be a mess. But now things are back to normal and low noise and I can crank up the gain again. There is always a chance that that the noise is from the ocean, but I don't think so. Did you noticed a jump in noise after the recent Big Ones. If so, is there any rule as to how long things take to cool off. Gary Gary Lindgren 585 Lincoln Ave Palo Alto CA 94301 650-326-0655 www.blue-eagle-technologies.com Check out Lastest Seismometer Reading cymonsplace.blogspot.com dtvtransitioninfo.blogspot.com Information on how to cope with the transition to DTV

After the big quakes in the South Pacific a couple = weeks ago it seems to me that the background noise was very high after the events = and stayed that way for many days. I had to lower the gain on my Lehman = otherwise the display would be a mess. But now things are back to normal and low = noise and I can crank up the gain again. There is always a chance that that = the noise is from the ocean, but I don’t think so. Did you noticed a jump in = noise after the recent Big Ones. If so, is there any rule as to how long = things take to cool off.

Gary

 

 

 

 

Gary Lindgren

585 Lincoln Ave

Palo Alto CA 94301

 

650-326-0655<= /span>

 

www.blue-eagle-technologies.com &nbs= p; Check out Lastest Seismometer = Reading

cymonsplace.blogspot.com =

dtvtransitioninfo.blogspot.com  = ;      Information on how to cope with the transition = to DTV

 

 

Subject: Re: Background Noise From: "tchannel" tchannel@............ Date: Fri, 16 Oct 2009 21:26:05 -0600 Gary, Don't know your circumstances, but I have a Lehman and know it is = sensitive to weather fronts. It will be normal, showing some day/night = time noise differences then when a cold front come through the noise = level gets very high, and in my case it only the weather. I have ruled = out temperature changes, sunny days, rainy days, even wind does not = produce the noise level of a weather front. Ted ----- Original Message -----=20 From: Gary Lindgren=20 To: psn-l@................. Sent: Friday, October 16, 2009 9:02 PM Subject: Background Noise After the big quakes in the South Pacific a couple weeks ago it seems = to me that the background noise was very high after the events and = stayed that way for many days. I had to lower the gain on my Lehman = otherwise the display would be a mess. But now things are back to normal = and low noise and I can crank up the gain again. There is always a = chance that that the noise is from the ocean, but I don't think so. Did = you noticed a jump in noise after the recent Big Ones. If so, is there = any rule as to how long things take to cool off. Gary =20 =20 =20 =20 Gary Lindgren 585 Lincoln Ave Palo Alto CA 94301 =20 650-326-0655 =20 www.blue-eagle-technologies.com Check out Lastest Seismometer = Reading cymonsplace.blogspot.com=20 dtvtransitioninfo.blogspot.com Information on how to cope with = the transition to DTV=20 =20 =20
Gary, Don't know your circumstances, = but I have a=20 Lehman and know it is sensitive to weather fronts.   It will = be=20 normal, showing some day/night time noise differences then when a = cold=20 front come through the noise level gets very high, and in my case it = only the=20 weather.   I have ruled out temperature changes, sunny days, = rainy=20 days, even wind does not produce the noise level of a weather=20 front.
 
Ted
----- Original Message -----
From:=20 Gary=20 Lindgren
Sent: Friday, October 16, 2009 = 9:02=20 PM
Subject: Background Noise

After the big quakes in the South Pacific a = couple weeks=20 ago it seems to me that the background noise was very high after the = events=20 and stayed that way for many days. I had to lower the gain on my = Lehman=20 otherwise the display would be a mess. But now things are back to = normal and=20 low noise and I can crank up the gain again. There is always a chance = that=20 that the noise is from the ocean, but I don=92t think so. Did you = noticed a jump=20 in noise after the recent Big Ones. If so, is there any rule as to how = long=20 things take to cool off.

Gary

 

 

 

 

Gary=20 Lindgren

585=20 Lincoln Ave

Palo=20 Alto CA 94301

 

650-326-0655

 

www.blue-eagle-technologies.com  =20 Check out Lastest Seismometer=20 Reading

cymonsplace.blogspot.com 

dtvtransitioninfo.blogspot.com    &n= bsp;  =20 Information on how to cope with the = transition to=20 DTV

 

 

Subject: Re: Background Noise From: ChrisAtUpw@....... Date: Sat, 17 Oct 2009 07:25:11 EDT =20 In a message dated 17/10/2009, _gel@..................... (mailto:gel@.................. writes:=20 After the big quakes in the South Pacific a couple weeks ago it seems to= =20 me that the background noise was very high after the events and stayed th= at=20 way for many days. But now things are back to normal and low noise and I= =20 can crank up the gain again. There is always a chance that that the noise= is=20 from the ocean, but I don=E2=80=99t think so. Did you noticed a jump in= noise after=20 the recent Big Ones. If so, is there any rule as to how long things take= =20 to cool off. Hi Gary,=20 These are almost certainly deep ocean microseisms, but you also get highe= r=20 signals when a storm system crosses the coast and when a cold front passe= s=20 through. You see signals like this world wide. There is a centre south of= =20 Greenland and another east of Japan. Waves on the west coast are likely= to=20 show up. See wave heights at _http://www.oceanweather.com/data/index.html_=20 (http://www.oceanweather.com/data/index.html)=20 With two Lehmans, you can estimate the direction. The rise and fall is likely to be several days minimum, similar to storm= =20 systems.=20 =20 Regards, =20 Chris
In a message dated 17/10/2009, gel@................. writes:

    After the big quakes in the South Pacific= a=20 couple weeks ago it seems to me that the background noise was very high af= ter=20 the events and stayed that way for many days. But now things are back to= normal=20 and low noise and I can crank up the gain again. There is always a chance= that=20 that the noise is from the ocean, but I don=E2=80=99t think so. Did you no= ticed a jump=20 in noise after the recent Big Ones. If so, is there any rule as to how lon= g=20 things take to cool off.
Hi Gary,

    These are almost certainly deep ocean=20 microseisms, but you also get higher signals when a storm system crosses= the=20 coast and when a cold front passes through. You see signals like this worl= d=20 wide. There is a centre south of Greenland and another east of Japan. Wave= s on=20 the west coast are likely to show up.
    See wave heights at http://www.oceanweath= er.com/data/index.html
    With two Lehmans, you can estimate the=20 direction.

    The rise and fall is likely to be several= days=20 minimum, similar to storm systems.
 
    Regards,
 
    Chris
 Subject: Warning: Computer trojan horse on JCLAHR.COM From: meredith lamb paleoartifact@......... Date: Sat, 17 Oct 2009 11:14:02 -0600 Hi all, My Norton/Symantec 360 program detects 15 instances of the computer trojan "Downloader" virus on the recently used link of JCLAHR.COM. My anti-virus program wouldn't even let me view the 15 page link/s....their maybe more.... If you've been there recently you're quite possibly, computer infected (?). "Downloader": This trojan horse is a program that downloads another malicious program from a remote internet site and executes it on the local system. Systems affected: Windows 2000, Windows 95, Windows 98, Windows Me, Windows NT, Windows XP For whatever its worth, I've used Norton/Symantec 360 for over a year and my recommendation is very high. One can do things with this program; the "others" don't even begin to do. Meredith Lamb Hi all,

My Norton/Symantec 360 program detects 15 instances of the c= omputer trojan "Downloader" virus on
the recently used link of= JCLAHR.COM.

My anti-virus program= wouldn't even let me view the 15 page link/s....their maybe more....= =A0

If you've been there recently you're quite possibly, computer i= nfected (?).

"Downloader":=A0 This trojan horse is a progr= am that downloads another malicious program from a remote
internet site = and executes it on the local system.

Systems affected:=A0 Windows 2000, Windows 95, Windows 98, Windows Me, = Windows NT, Windows XP

For whatever its worth, I've used Norton/= Symantec 360 for over a year and my recommendation is very high.
One can= do things with this program; the "others" don't even begin t= o do.

Meredith Lamb










=A0=A0=A0
=

Subject: Re: Warning: Computer trojan horse on JCLAHR.COM From: "GPayton" gpayton@............. Date: Sat, 17 Oct 2009 12:37:22 -0500 I too received this notice from Norton when accessing the site. However, I am not sure that notice is current or even accurate. It says that Norton "looked at" that site and found the problems. WHEN is my question. In fact, I sent them an email to them to re-check; that it was a very important source of information, but got no reply and the error notice still appears when I go there. Nevertheless, since then I have had my machine scanned numerous times since with no infections found; Norton and other scanners. I doubt the veracity of that notice, but do not know how to remedy. Jerry ----- Original Message ----- From: meredith lamb To: psn-l@.............. Sent: Saturday, October 17, 2009 12:14 PM Subject: Warning: Computer trojan horse on JCLAHR.COM Hi all, My Norton/Symantec 360 program detects 15 instances of the computer Trojan "Downloader" virus on the recently used link of JCLAHR.COM. My anti-virus program wouldn't even let me view the 15 page link/s....their maybe more.... If you've been there recently you're quite possibly, computer infected (?). "Downloader": This Trojan horse is a program that downloads another malicious program from a remote internet site and executes it on the local system. Systems affected: Windows 2000, Windows 95, Windows 98, Windows Me, Windows NT, Windows XP For whatever its worth, I've used Norton/Symantec 360 for over a year and my recommendation is very high. One can do things with this program; the "others" don't even begin to do. Meredith Lamb
I too received this notice from Norton when = accessing the=20 site.  However, I am not sure that notice is current or even=20 accurate.  It says that Norton "looked at" that site and found the=20 problems.  WHEN is my question.  In fact, I sent them an email = to them=20 to re-check; that it was a very important source of information, but got = no=20 reply and the error notice still appears when I go there.
 
Nevertheless, since then I have had my machine = scanned=20 numerous times since with no infections found; Norton and other=20 scanners.
 
I doubt the veracity of that notice, but do not = know how=20 to remedy.
 
Jerry
 
----- Original Message -----
From:=20 meredith lamb
Sent: Saturday, October 17, = 2009 12:14=20 PM
Subject: Warning: Computer = trojan horse=20 on JCLAHR.COM

Hi all,

My Norton/Symantec 360 program detects = 15=20 instances of the computer Trojan "Downloader" virus on
the recently = used=20 link of JCLAHR.COM.

My = anti-virus=20 program wouldn't even let me view the 15 page link/s....their maybe=20 more.... 

If you've been there recently you're quite = possibly,=20 computer infected (?).

"Downloader":  This Trojan horse is = a=20 program that downloads another malicious program from a = remote
internet=20 site and executes it on the local system.

Systems = affected: =20 Windows 2000, Windows 95, Windows 98, Windows Me, Windows NT, Windows=20 XP

For whatever its worth, I've used Norton/Symantec 360 for = over a=20 year and my recommendation is very high.
One can do things with = this=20 program; the "others" don't even begin to do.

Meredith=20 Lamb










   =20


Subject: Re: Warning: Computer trojan horse on JCLAHR.COM From: =?ISO-8859-1?Q?J=F3n_Fr=EDmann?= jonfr@......... Date: Sat, 17 Oct 2009 17:43:56 +0000 Hi, Google gives me a clean page, and up on viewing the web page I don't see anything that indicates a virus (I am running Gentoo Linux). Regards, J=F3n Fr=EDmann. On lau, 2009-10-17 at 11:14 -0600, meredith lamb wrote: > Hi all, >=20 > My Norton/Symantec 360 program detects 15 instances of the computer > trojan "Downloader" virus on > the recently used link of JCLAHR.COM. >=20 > My anti-virus program wouldn't even let me view the 15 page > link/s....their maybe more.... =20 >=20 > If you've been there recently you're quite possibly, computer infected > (?). >=20 > "Downloader": This trojan horse is a program that downloads another > malicious program from a remote > internet site and executes it on the local system. >=20 > Systems affected: Windows 2000, Windows 95, Windows 98, Windows Me, > Windows NT, Windows XP >=20 > For whatever its worth, I've used Norton/Symantec 360 for over a year > and my recommendation is very high. > One can do things with this program; the "others" don't even begin to > do. >=20 > Meredith Lamb >=20 >=20 >=20 >=20 >=20 >=20 >=20 >=20 >=20 >=20 > =20 >=20 __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Warning: Computer trojan horse on JCLAHR.COM From: "GPayton" gpayton@............. Date: Sat, 17 Oct 2009 13:27:32 -0500 Meredith, perhaps if we joined http://safeweb.norton.com/about we could all complain and have them check it again. It appears to be an automatic service from Norton, outside of the A/V installed on one's computer, and associated with the Norton Toolbar that automatically installs with your A/V installation. Jon, I do not think it would affect a Linux machine or software. Jerry ----- Original Message ----- From: meredith lamb To: psn-l@.............. Sent: Saturday, October 17, 2009 12:14 PM Subject: Warning: Computer trojan horse on JCLAHR.COM Hi all, My Norton/Symantec 360 program detects 15 instances of the computer trojan "Downloader" virus on the recently used link of JCLAHR.COM. My anti-virus program wouldn't even let me view the 15 page link/s....their maybe more.... If you've been there recently you're quite possibly, computer infected (?). "Downloader": This trojan horse is a program that downloads another malicious program from a remote internet site and executes it on the local system. Systems affected: Windows 2000, Windows 95, Windows 98, Windows Me, Windows NT, Windows XP For whatever its worth, I've used Norton/Symantec 360 for over a year and my recommendation is very high. One can do things with this program; the "others" don't even begin to do. Meredith Lamb
Meredith, perhaps if we joined  http://safeweb.norton.com/about<= /A> =20 we could all complain and have them check it again. 
 
It appears to be an automatic = service from=20 Norton, outside of the A/V installed on one's computer, and associated = with the=20 Norton Toolbar that automatically installs with your = A/V=20 installation. 
 
Jon, I do not think it would affect a Linux = machine or=20 software.
 
Jerry
----- Original Message -----
From:=20 meredith lamb
Sent: Saturday, October 17, = 2009 12:14=20 PM
Subject: Warning: Computer = trojan horse=20 on JCLAHR.COM

Hi all,

My Norton/Symantec 360 program detects = 15=20 instances of the computer trojan "Downloader" virus on
the recently = used=20 link of JCLAHR.COM.

My = anti-virus=20 program wouldn't even let me view the 15 page link/s....their maybe=20 more.... 

If you've been there recently you're quite = possibly,=20 computer infected (?).

"Downloader":  This trojan horse is = a=20 program that downloads another malicious program from a = remote
internet=20 site and executes it on the local system.

Systems = affected: =20 Windows 2000, Windows 95, Windows 98, Windows Me, Windows NT, Windows=20 XP

For whatever its worth, I've used Norton/Symantec 360 for = over a=20 year and my recommendation is very high.
One can do things with = this=20 program; the "others" don't even begin to do.

Meredith=20 Lamb










   =20


Subject: Re: Warning: Computer trojan horse on JCLAHR.COM From: =?ISO-8859-1?Q?J=F3n_Fr=EDmann?= jonfr@......... Date: Sat, 17 Oct 2009 18:46:23 +0000 Hi, I found the issue on that webpage. There is a java injection code on the web pages, it does not show up clearly. It does not affect Linux and MacOS X. The hosting of the web page has been injected with the infection web code. This post is being CC to the site mainterers. More information here, http://www.google.com/support/forum/p/Webmasters/thread?tid=3D363527b28d167= 514&hl=3Den This email is beging Cc to the site maintanier so this issue can be fixed. Regards, J=F3n Fr=EDmann. On lau, 2009-10-17 at 13:27 -0500, GPayton wrote: > Meredith, perhaps if we joined http://safeweb.norton.com/about we > could all complain and have them check it again. =20 > =20 > It appears to be an automatic service from Norton, outside of the A/V > installed on one's computer, and associated with the Norton Toolbar > that automatically installs with your A/V installation. =20 > =20 > Jon, I do not think it would affect a Linux machine or software. > =20 > Jerry > ----- Original Message -----=20 > From: meredith lamb=20 > To: psn-l@................. > Sent: Saturday, October 17, 2009 12:14 PM > Subject: Warning: Computer trojan horse on JCLAHR.COM > =20 > =20 > Hi all, > =20 > My Norton/Symantec 360 program detects 15 instances of the > computer trojan "Downloader" virus on > the recently used link of JCLAHR.COM. > =20 > My anti-virus program wouldn't even let me view the 15 page > link/s....their maybe more.... =20 > =20 > If you've been there recently you're quite possibly, computer > infected (?). > =20 > "Downloader": This trojan horse is a program that downloads > another malicious program from a remote > internet site and executes it on the local system. > =20 > Systems affected: Windows 2000, Windows 95, Windows 98, > Windows Me, Windows NT, Windows XP > =20 > For whatever its worth, I've used Norton/Symantec 360 for over > a year and my recommendation is very high. > One can do things with this program; the "others" don't even > begin to do. > =20 > Meredith Lamb > =20 > =20 > =20 > =20 > =20 > =20 > =20 > =20 > =20 > =20 > =20 > =20 __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Warning: Computer trojan horse on JCLAHR.COM From: rg richg_1998@......... Date: Sat, 17 Oct 2009 12:04:46 -0700 (PDT) I use Linux Mint 7. No problems here. Rich O.S. Linux Mint 7 No Gates or Windows __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Warning: Computer trojan horse on JCLAHR.COM From: "GPayton" gpayton@............. Date: Sat, 17 Oct 2009 14:49:46 -0500 Meredith, A solution "may" be here: http://www.gotknowhow.com/articles/how-to-turn-off-norton-safe-web.aspx However, turning off the "enhanced search engine feature" might promote other undesirable exclusions. On the other hand, my Norton A/N catches problems and blocks them when on a website. ANY a/v program cannot be 100% as viruses are constantly added, bit it is the best we can do. I think you would loose the green check mark circles seen in a Google search also. Jerry ----- Original Message ----- From: meredith lamb To: psn-l@.............. Sent: Saturday, October 17, 2009 12:14 PM Subject: Warning: Computer trojan horse on JCLAHR.COM Hi all, My Norton/Symantec 360 program detects 15 instances of the computer trojan "Downloader" virus on the recently used link of JCLAHR.COM. My anti-virus program wouldn't even let me view the 15 page link/s....their maybe more.... If you've been there recently you're quite possibly, computer infected (?). "Downloader": This trojan horse is a program that downloads another malicious program from a remote internet site and executes it on the local system. Systems affected: Windows 2000, Windows 95, Windows 98, Windows Me, Windows NT, Windows XP For whatever its worth, I've used Norton/Symantec 360 for over a year and my recommendation is very high. One can do things with this program; the "others" don't even begin to do. Meredith Lamb
Meredith,
 
A solution "may" be here:  http://www.gotknowhow.com/articles/how-to-turn-off-norton-safe-we= b.aspx
 
However, turning off the "enhanced search engine = feature"=20 might promote other undesirable exclusions.  On the other hand, my = Norton=20 A/N catches problems and blocks them when on a website.  ANY a/v = program=20 cannot be 100% as viruses are constantly added, bit it is the best we = can=20 do.
 
I think you would loose the green check mark = circles seen=20 in a Google search also.
 
Jerry
 
 
----- Original Message -----
From:=20 meredith lamb
Sent: Saturday, October 17, = 2009 12:14=20 PM
Subject: Warning: Computer = trojan horse=20 on JCLAHR.COM

Hi all,

My Norton/Symantec 360 program detects = 15=20 instances of the computer trojan "Downloader" virus on
the recently = used=20 link of JCLAHR.COM.

My = anti-virus=20 program wouldn't even let me view the 15 page link/s....their maybe=20 more.... 

If you've been there recently you're quite = possibly,=20 computer infected (?).

"Downloader":  This trojan horse is = a=20 program that downloads another malicious program from a = remote
internet=20 site and executes it on the local system.

Systems = affected: =20 Windows 2000, Windows 95, Windows 98, Windows Me, Windows NT, Windows=20 XP

For whatever its worth, I've used Norton/Symantec 360 for = over a=20 year and my recommendation is very high.
One can do things with = this=20 program; the "others" don't even begin to do.

Meredith=20 Lamb










   =20


Subject: Re: Warning: Computer trojan horse on JCLAHR.COM From: "Geoffrey" gmvoeth@........... Date: Sat, 17 Oct 2009 12:56:39 -0700 Was this so called malware riding on a downloaded file or just how did it get into your machine ? I have never received bad files to my knowledge without having a virus be a part of executable code in something intentionally downloaded. Then it gets saved to the recovery files automatically forcing you to reset the recovery points to get rid of the bad messages ? I would recommend possibly immunizing your machine with spybot which loads a mess of bad sites into your normal browser blocking security thingy. Then you donate maybe $5 to them for being such nice folks. Sure beats all the moola they want every year for whatever scanners. But many times I wonder seriously if the anti virus peoples are hiring or encouraging other third parties to make viruses in some kind of collusional scheme to keep alive the scanner thingy I always thought was so ridiculous in the first place. If windows would remove all those hidden servers that run in the background as well as any interpreter programs there would be no worries unless you run the bad code yourself. SERVERS and Interpreters are the only kind of bad things I know a system may have that will allow others to control or destroy your machine. (Like Blasting the bios or wiping or corrupting) As for spyware the USA does not allow the private citizen the pleasure of keeping secrets, only that stupid thing called privacy which essentially protects you from nothing at all. Privacy means anyone can watch what they want and must turn their heads unless something is illegal. ----- Original Message ----- From: "meredith lamb" To: Sent: Saturday, October 17, 2009 10:14 AM Subject: Warning: Computer trojan horse on JCLAHR.COM > Hi all, > > My Norton/Symantec 360 program detects 15 instances of the computer trojan > "Downloader" virus on > the recently used link of JCLAHR.COM. > > My anti-virus program wouldn't even let me view the 15 page link/s....their > maybe more.... > > If you've been there recently you're quite possibly, computer infected (?). > > "Downloader": This trojan horse is a program that downloads another > malicious program from a remote > internet site and executes it on the local system. > > Systems affected: Windows 2000, Windows 95, Windows 98, Windows Me, Windows > NT, Windows XP > > For whatever its worth, I've used Norton/Symantec 360 for over a year and my > recommendation is very high. > One can do things with this program; the "others" don't even begin to do. > > Meredith Lamb > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Warning: Computer trojan horse on JCLAHR.COM From: "GPayton" gpayton@............. Date: Sat, 17 Oct 2009 15:05:33 -0500 Hi Goeff. For clarification, nobody's machine is infected! The problem that Norton shows a warning window that John Clahr's website http://jclahr.com/ is infected. We believe it is NOT. It seems to be a problem with Norton's installation of their Toolbar and Norton Safe Web settings. Disabling the latter removes the popup and the site cause NO problems with normal a/v searches. Regards, Jerry ----- Original Message ----- From: "Geoffrey" To: Sent: Saturday, October 17, 2009 2:56 PM Subject: Re: Warning: Computer trojan horse on JCLAHR.COM > Was this so called malware riding on a downloaded file > or just how did it get into your machine ? > > I have never received bad files to my knowledge > without having a virus be a part of > executable code in something intentionally > downloaded. > > Then it gets saved to the recovery files > automatically forcing you to reset the > recovery points to get rid of the bad messages ? > > I would recommend possibly immunizing your > machine with spybot which loads a mess > of bad sites into your normal browser > blocking security thingy. > > Then you donate maybe $5 to them for > being such nice folks. > > Sure beats all the moola they want every > year for whatever scanners. > > But many times I wonder seriously if the > anti virus peoples are hiring or encouraging > other third parties to make viruses in some > kind of collusional scheme to keep alive > the scanner thingy I always thought was > so ridiculous in the first place. > > > If windows would remove all those hidden servers > that run in the background as well as any interpreter > programs there would be no worries unless you run the bad > code yourself. > > SERVERS and Interpreters are the only kind of bad > things I know a system may have that will > allow others to control or destroy your machine. > (Like Blasting the bios or wiping or corrupting) > As for spyware the USA does not allow the private > citizen the pleasure of keeping secrets, only that > stupid thing called privacy which essentially > protects you from nothing at all. > Privacy means anyone can watch what they want > and must turn their heads unless something is illegal. > > > ----- Original Message ----- > From: "meredith lamb" > To: > Sent: Saturday, October 17, 2009 10:14 AM > Subject: Warning: Computer trojan horse on JCLAHR.COM > > >> Hi all, >> >> My Norton/Symantec 360 program detects 15 instances of the computer >> trojan >> "Downloader" virus on >> the recently used link of JCLAHR.COM. >> >> My anti-virus program wouldn't even let me view the 15 page >> link/s....their >> maybe more.... >> >> If you've been there recently you're quite possibly, computer infected >> (?). >> >> "Downloader": This trojan horse is a program that downloads another >> malicious program from a remote >> internet site and executes it on the local system. >> >> Systems affected: Windows 2000, Windows 95, Windows 98, Windows Me, >> Windows >> NT, Windows XP >> >> For whatever its worth, I've used Norton/Symantec 360 for over a year and >> my >> recommendation is very high. >> One can do things with this program; the "others" don't even begin to do. >> >> Meredith Lamb >> > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with the body of the > message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Warning: Computer trojan horse on JCLAHR.COM From: =?ISO-8859-1?Q?J=F3n_Fr=EDmann?= jonfr@......... Date: Sat, 17 Oct 2009 20:24:58 +0000 Hi, The web page is infected, there is no doubt about it. It is a java injection code. It is hard to detect it, but it is there. I did check for it manually. Regards, J=F3n Fr=EDmann. On lau, 2009-10-17 at 15:05 -0500, GPayton wrote: > Hi Goeff. >=20 > For clarification, nobody's machine is infected! The problem that Norton= =20 > shows a warning window that John Clahr's website http://jclahr.com/ is= =20 > infected. We believe it is NOT. It seems to be a problem with Norton's=20 > installation of their Toolbar and Norton Safe Web settings. Disabling th= e=20 > latter removes the popup and the site cause NO problems with normal a/v=20 > searches. >=20 > Regards, > Jerry >=20 >=20 > ----- Original Message -----=20 > From: "Geoffrey" > To: > Sent: Saturday, October 17, 2009 2:56 PM > Subject: Re: Warning: Computer trojan horse on JCLAHR.COM >=20 >=20 > > Was this so called malware riding on a downloaded file > > or just how did it get into your machine ? > > > > I have never received bad files to my knowledge > > without having a virus be a part of > > executable code in something intentionally > > downloaded. > > > > Then it gets saved to the recovery files > > automatically forcing you to reset the > > recovery points to get rid of the bad messages ? > > > > I would recommend possibly immunizing your > > machine with spybot which loads a mess > > of bad sites into your normal browser > > blocking security thingy. > > > > Then you donate maybe $5 to them for > > being such nice folks. > > > > Sure beats all the moola they want every > > year for whatever scanners. > > > > But many times I wonder seriously if the > > anti virus peoples are hiring or encouraging > > other third parties to make viruses in some > > kind of collusional scheme to keep alive > > the scanner thingy I always thought was > > so ridiculous in the first place. > > > > > > If windows would remove all those hidden servers > > that run in the background as well as any interpreter > > programs there would be no worries unless you run the bad > > code yourself. > > > > SERVERS and Interpreters are the only kind of bad > > things I know a system may have that will > > allow others to control or destroy your machine. > > (Like Blasting the bios or wiping or corrupting) > > As for spyware the USA does not allow the private > > citizen the pleasure of keeping secrets, only that > > stupid thing called privacy which essentially > > protects you from nothing at all. > > Privacy means anyone can watch what they want > > and must turn their heads unless something is illegal. > > > > > > ----- Original Message -----=20 > > From: "meredith lamb" > > To: > > Sent: Saturday, October 17, 2009 10:14 AM > > Subject: Warning: Computer trojan horse on JCLAHR.COM > > > > > >> Hi all, > >> > >> My Norton/Symantec 360 program detects 15 instances of the computer=20 > >> trojan > >> "Downloader" virus on > >> the recently used link of JCLAHR.COM. > >> > >> My anti-virus program wouldn't even let me view the 15 page=20 > >> link/s....their > >> maybe more.... > >> > >> If you've been there recently you're quite possibly, computer infected= =20 > >> (?). > >> > >> "Downloader": This trojan horse is a program that downloads another > >> malicious program from a remote > >> internet site and executes it on the local system. > >> > >> Systems affected: Windows 2000, Windows 95, Windows 98, Windows Me,=20 > >> Windows > >> NT, Windows XP > >> > >> For whatever its worth, I've used Norton/Symantec 360 for over a year = and=20 > >> my > >> recommendation is very high. > >> One can do things with this program; the "others" don't even begin to = do. > >> > >> Meredith Lamb > >> > > __________________________________________________________ > > > > Public Seismic Network Mailing List (PSN-L) > > > > To leave this list email PSN-L-REQUEST@.............. with the body of = the=20 > > message (first line only): unsubscribe > > See http://www.seismicnet.com/maillist.html for more information. > >=20 >=20 >=20 > __________________________________________________________ >=20 > Public Seismic Network Mailing List (PSN-L) >=20 > To leave this list email PSN-L-REQUEST@.............. with=20 > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Warning: Computer trojan horse on JCLAHR.COM From: "Kay Wyatt" kwyatt@............. Date: Sat, 17 Oct 2009 18:32:49 -0700 Folks, I am still in the process of removing the computer virus from John = Lahr's website. I am at a conference in Portland, OR, right now but = will be back on Monday evening to finish up. Thanks for your patience. Kay Wyatt ----- Original Message -----=20 From: meredith lamb=20 To: psn-l@................. Sent: Saturday, October 17, 2009 10:14 AM Subject: Warning: Computer trojan horse on JCLAHR.COM Hi all, My Norton/Symantec 360 program detects 15 instances of the computer = trojan "Downloader" virus on the recently used link of JCLAHR.COM. My anti-virus program wouldn't even let me view the 15 page = link/s....their maybe more.... =20 If you've been there recently you're quite possibly, computer infected = (?). "Downloader": This trojan horse is a program that downloads another = malicious program from a remote internet site and executes it on the local system. Systems affected: Windows 2000, Windows 95, Windows 98, Windows Me, = Windows NT, Windows XP For whatever its worth, I've used Norton/Symantec 360 for over a year = and my recommendation is very high. One can do things with this program; the "others" don't even begin to = do. Meredith Lamb =20
Folks,
I am still in the process of removing the = computer virus=20 from John Lahr's website.  I am at a conference in Portland, OR, = right now=20 but will be back on Monday evening to finish up.  Thanks for your=20 patience.
Kay Wyatt
 
 
----- Original Message -----
From:=20 meredith lamb
Sent: Saturday, October 17, = 2009 10:14=20 AM
Subject: Warning: Computer = trojan horse=20 on JCLAHR.COM

Hi all,

My Norton/Symantec 360 program detects = 15=20 instances of the computer trojan "Downloader" virus on
the recently = used=20 link of JCLAHR.COM.

My = anti-virus=20 program wouldn't even let me view the 15 page link/s....their maybe=20 more.... 

If you've been there recently you're quite = possibly,=20 computer infected (?).

"Downloader":  This trojan horse is = a=20 program that downloads another malicious program from a = remote
internet=20 site and executes it on the local system.

Systems = affected: =20 Windows 2000, Windows 95, Windows 98, Windows Me, Windows NT, Windows=20 XP

For whatever its worth, I've used Norton/Symantec 360 for = over a=20 year and my recommendation is very high.
One can do things with = this=20 program; the "others" don't even begin to do.

Meredith=20 Lamb










   =20


Subject: Re: Warning: Computer trojan horse on JCLAHR.COM From: "Kay Wyatt" kwyatt@............. Date: Sat, 17 Oct 2009 18:36:26 -0700 Just a little more information. John hosted his website with iPower.com = and awhile back a Trojan got into several of their servers. It = basically ate into all the index.htm or index.html files. I am = systematically fixing the hundreds of files and am almost done. Please = be patient. John's website is so important to all of us and I don't = want folks to not use it. I'll keep you posted on my progress next = week. Thanks! Kay ----- Original Message -----=20 From: GPayton=20 To: psn-l@................. Sent: Saturday, October 17, 2009 11:27 AM Subject: Re: Warning: Computer trojan horse on JCLAHR.COM Meredith, perhaps if we joined http://safeweb.norton.com/about we = could all complain and have them check it again. =20 It appears to be an automatic service from Norton, outside of the A/V = installed on one's computer, and associated with the Norton Toolbar that = automatically installs with your A/V installation. =20 Jon, I do not think it would affect a Linux machine or software. Jerry ----- Original Message -----=20 From: meredith lamb=20 To: psn-l@................. Sent: Saturday, October 17, 2009 12:14 PM Subject: Warning: Computer trojan horse on JCLAHR.COM Hi all, My Norton/Symantec 360 program detects 15 instances of the computer = trojan "Downloader" virus on the recently used link of JCLAHR.COM. My anti-virus program wouldn't even let me view the 15 page = link/s....their maybe more.... =20 If you've been there recently you're quite possibly, computer = infected (?). "Downloader": This trojan horse is a program that downloads another = malicious program from a remote internet site and executes it on the local system. Systems affected: Windows 2000, Windows 95, Windows 98, Windows Me, = Windows NT, Windows XP For whatever its worth, I've used Norton/Symantec 360 for over a = year and my recommendation is very high. One can do things with this program; the "others" don't even begin = to do. Meredith Lamb =20
Just a little more information.  John = hosted his=20 website with iPower.com and awhile back a Trojan got into several of = their=20 servers.  It basically ate into all the index.htm or index.html=20 files.  I am systematically fixing the hundreds of files and am = almost=20 done.  Please be patient.  John's website is so important to = all of us=20 and I don't want folks to not use it.  I'll keep you posted on my = progress=20 next week.
Thanks!
Kay
 
----- Original Message -----
From:=20 GPayton=20
Sent: Saturday, October 17, = 2009 11:27=20 AM
Subject: Re: Warning: Computer = trojan=20 horse on JCLAHR.COM

Meredith, perhaps if we joined  http://safeweb.norton.com/about<= /A> =20 we could all complain and have them check it again.  =
 
It appears to be an automatic = service from=20 Norton, outside of the A/V installed on one's computer, and associated = with=20 the Norton Toolbar that automatically installs with = your A/V=20 installation. 
 
Jon, I do not think it would affect a Linux = machine or=20 software.
 
Jerry
----- Original Message -----
From:=20 meredith lamb
Sent: Saturday, October 17, = 2009 12:14=20 PM
Subject: Warning: Computer = trojan horse=20 on JCLAHR.COM

Hi all,

My Norton/Symantec 360 program detects = 15=20 instances of the computer trojan "Downloader" virus on
the = recently used=20 link of JCLAHR.COM.

My = anti-virus=20 program wouldn't even let me view the 15 page link/s....their maybe=20 more.... 

If you've been there recently you're quite = possibly,=20 computer infected (?).

"Downloader":  This trojan horse = is a=20 program that downloads another malicious program from a = remote
internet=20 site and executes it on the local system.

Systems = affected: =20 Windows 2000, Windows 95, Windows 98, Windows Me, Windows NT, = Windows=20 XP

For whatever its worth, I've used Norton/Symantec 360 for = over a=20 year and my recommendation is very high.
One can do things with = this=20 program; the "others" don't even begin to do.

Meredith=20 Lamb










   =20


Subject: RE: Warning: Computer trojan horse on JCLAHR.COM From: "Kareem" system98765@............. Date: Sat, 17 Oct 2009 19:12:51 -0700 I used iPower years ago but decided to switch. From: psn-l-request@.............. [mailto:psn-l-request@............... On Behalf Of Kay Wyatt Sent: Saturday, October 17, 2009 6:36 PM To: psn-l@.............. Subject: Re: Warning: Computer trojan horse on JCLAHR.COM Just a little more information. John hosted his website with iPower.com and awhile back a Trojan got into several of their servers. It basically ate into all the index.htm or index.html files. I am systematically fixing the hundreds of files and am almost done. Please be patient. John's website is so important to all of us and I don't want folks to not use it. I'll keep you posted on my progress next week. Thanks! Kay ----- Original Message ----- From: GPayton To: psn-l@.............. Sent: Saturday, October 17, 2009 11:27 AM Subject: Re: Warning: Computer trojan horse on JCLAHR.COM Meredith, perhaps if we joined http://safeweb.norton.com/about we could all complain and have them check it again. It appears to be an automatic service from Norton, outside of the A/V installed on one's computer, and associated with the Norton Toolbar that automatically installs with your A/V installation. Jon, I do not think it would affect a Linux machine or software. Jerry ----- Original Message ----- From: meredith lamb To: psn-l@.............. Sent: Saturday, October 17, 2009 12:14 PM Subject: Warning: Computer trojan horse on JCLAHR.COM Hi all, My Norton/Symantec 360 program detects 15 instances of the computer trojan "Downloader" virus on the recently used link of JCLAHR.COM. My anti-virus program wouldn't even let me view the 15 page link/s....their maybe more.... If you've been there recently you're quite possibly, computer infected (?). "Downloader": This trojan horse is a program that downloads another malicious program from a remote internet site and executes it on the local system. Systems affected: Windows 2000, Windows 95, Windows 98, Windows Me, Windows NT, Windows XP For whatever its worth, I've used Norton/Symantec 360 for over a year and my recommendation is very high. One can do things with this program; the "others" don't even begin to do. Meredith Lamb

I used iPower years ago but decided to = switch.

 

From:= = psn-l-request@.............. [mailto:psn-l-request@............... On Behalf Of Kay Wyatt
Sent: Saturday, October 17, 2009 6:36 PM
To: psn-l@..............
Subject: Re: Warning: Computer trojan horse on = JCLAHR.COM

 

Just a little more information.  John hosted his website with iPower.com and = awhile back a Trojan got into several of their servers.  It basically ate into = all the index.htm or index.html files.  I am systematically fixing the = hundreds of files and am almost done.  Please be patient.  John's website = is so important to all of us and I don't want folks to not use it.  I'll = keep you posted on my progress next week.

Thanks!

Kay

 

----- Original Message -----

From: GPayton

Sent:<= /b> Saturday, = October 17, 2009 11:27 AM

Subject: Re: = Warning: Computer trojan horse on JCLAHR.COM

 

 

It appears to be an automatic service from Norton, outside of the A/V = installed on one's computer, and associated with the Norton Toolbar that automatically installs with your A/V installation. 

 

Jon, I do not think it would affect a Linux machine or software.

 

Jerry

----- Original Message -----

Sent:<= /b> Saturday, = October 17, 2009 12:14 PM

Subject: Warning: = Computer trojan horse on JCLAHR.COM

 

Hi all,

My Norton/Symantec 360 program detects 15 instances of the computer = trojan "Downloader" virus on
the recently used link of JCLAHR.COM.

My anti-virus program wouldn't even let me view the 15 page = link/s....their maybe more.... 

If you've been there recently you're quite possibly, computer infected = (?).

"Downloader":  This trojan horse is a program that = downloads another malicious program from a remote
internet site and executes it on the local system.

Systems affected:  Windows 2000, Windows 95, Windows 98, Windows = Me, Windows NT, Windows XP

For whatever its worth, I've used Norton/Symantec 360 for over a year = and my recommendation is very high.
One can do things with this program; the "others" don't even = begin to do.

Meredith Lamb










   

Subject: Re: Digest from 10/15/2009 00:01:59 From: ChrisAtUpw@....... Date: Sun, 18 Oct 2009 20:51:20 EDT _http://tinkeringcaveman.googlepages.com/home_ (http://tinkeringcaveman.googlepages.com/home) In a message dated 16/10/2009, kevin.mckee@....... writes: >> Perhaps one or both of my postings weren't clear. Hi Kevin, You say: >> "Do your homework! A lot of folks out there have already done this, save yourself time, effort, and money by doing some research." Them why have you chosen to use a photo transistor detector? This has over a hundred times the noise of a photo diode detector and it seriously limits the performance. You say: >> "Be Patient! Patience is a necessary virtue for a seismologist. It turns out that in my location near Washington D.C., there is limited seismicity; I sometimes go for a month at a time without detecting distant quakes." I also live in a quiet seismic area, but it is a QUIET WEEK when I don't see TWO QUAKES. Call up the drumplot of a local professional station to check what quakes you should see? >> Because that temperature varies over relatively long times, however, I judge that it is trivial after considering that the ac-coupled integrator suppresses signals longer than about 20 seconds. You can see convective thermal fluctuations with periods from just a few seconds upwards. >> Also, the instruments use glass fibers for the torsion fiber. You need to use a single fibre or wire suspension. If you use a bundle of fibres there will be frictional effects in the suspension which allow the zero position to wander from quake to quake. >> I recognize that this instrument is not a lab quality instrument, but for something that can be built so cheaply and easily by anyone without a lot of technical or machining skills it's a very useful device. I've detected at least 120 earthquakes from all over the world with it. >> Why discourage folks out there who don't have the skills or $ to build a Porsche when a Ford will get the job done, while spreading the fun of doing science? Maybe because your 'design' does not seem to be even in the model T Ford class? The design seems to be mostly built inside a jar. This increases the construction difficulty and is not neccessary. It would be a lot easier to construct the mechanism on two or three disks connected by three lengths of threaded rod. The completed and adjusted mechanism could then be slid inside the glass jar. How is the period set up, measured and adjusted? How is the damping measured and adjusted to ~0.7 critical? Note that coins are a copper alloy, have a much higher electrical resistance than pure copper and don't make such efficient dampers. I have no interest in trying to make a low specification device. And I don't fancy the hassle of "The initial set-up may take several hours, and then you need to monitor or record the output for days or weeks to determine if you are getting adequate results." Amateur seismologists try to detect the same quakes as the professionals and require similar low noise high performance systems. If a seismic system does not work down to below the local seismic background noise, it is a waste of time, effort and money. This looks like it was based on a Wood Anderson 0.8 second period seismometer _ http://www.data.scec.org/Module/s3inset3.html_ (http://www.data.scec.org/Module/s3inset3.html) _ http://www.eas.slu.edu/Earthquake_Center/Instruments/torsion_seis.html_ (http://www.eas.slu.edu/Earthquake_Center/Instruments/torsion_seis.html) Regards, Chris Chapman
http://tinkeringcave= man.googlepages.com/home
In a message dated 16/10/2009, kevin.mckee@....... writes:
>>    Perhaps one or both of my= postings=20 weren't clear.
Hi Kevin,
 
    You say:
>> "Do your homework! A lot of folks out there have alread= y done=20 this, save yourself time, effort, and money by doing some research."
 
    Them why have you chosen to use a photo= =20 transistor detector? This has over a hundred times the noise of a photo di= ode=20 detector and it seriously limits the performance.
 
 You say:
>>  "Be Patient! Patience is a necessary virtue for= a=20 seismologist. It turns out that in my location near Washington D.C., there= is=20 limited seismicity; I sometimes go for a month at a time without detecting= =20 distant quakes."
 
    I also live in a quiet seismic area, but= it is=20 a QUIET WEEK when I don't see TWO QUAKES. Call up the drumplot of a=20 local professional station to check what quakes you should see? =
 
>>    Because that temperature vari= es over=20 relatively long times, however, I judge that it is trivial after consideri= ng=20 that the ac-coupled integrator suppresses signals longer than about 20=20 seconds.
 
    You can see convective thermal= =20 fluctuations with periods from just a few seconds=20 upwards. 

>>    Also, the instrument= s use=20 glass fibers for the torsion fiber.
 
    You need to use a single fibre or wir= e=20 suspension. If you use a bundle of fibres there will be frictional effects= in=20 the suspension which allow the zero position to wander from quake to=20 quake.

>>    I recognize that this instrument= is not=20 a lab quality instrument, but for something that can be built so cheaply= and=20 easily by anyone without a lot of technical or machining skills it's a ver= y=20 useful device. I've detected at least 120 earthquakes from all over the wo= rld=20 with it.

>>    Why discourage folks out= there=20 who don't have the skills or $ to build a Porsche when a Ford will get the= job=20 done, while spreading the fun of doing science?

 
    Maybe because your 'design' does not seem=20 to be even in the model T Ford class?
    
    The design seems to be mostly built inside a= jar.=20 This increases the construction difficulty and is not neccessary. It would= be a=20 lot easier to construct the mechanism on two or three disks connected by= three=20 lengths of threaded rod. The completed and adjusted mechanism co= uld=20 then be slid inside the glass jar. 
    How is the period set up, measured=20 and adjusted? How is the damping measured and adjusted to ~0.7=20 critical? Note that coins are a copper alloy, have a much higher elec= trical=20 resistance than pure copper and don't make such efficient dampers.
 
    I have no interest in trying to make a low=20 specification device. And I don't fancy the hassle of "The initi= al=20 set-up may take several hours, and then you need to monitor or record the= output=20 for days or weeks to determine if you are getting adequate results."
 
    Amateur seismologists try to detect the same= quakes=20 as the professionals and require similar low noise high performance system= s. If=20 a seismic system does not work down to below the local seismic background= noise,=20 it is a waste of time, effort and money.
 
    This looks like it was based on a Wood= =20 Anderson 0.8 second period seismometer     &= nbsp;http://www.data.scec.org/Module/s3inset3.html 
    http://www.eas.slu.edu/Earthquake_Center/Ins= truments/torsion_seis.html
 
    Regards,
 
    Chris Chapman
Subject: Instrument quality From: "Randy Pratt" rpratt@............. Date: Mon, 19 Oct 2009 10:43:43 -0500 Chris, There are also many battles out here that need fighting in addition to = getting the last nanometer resolution from a homebrew seismometer. For = the past nine years I have been involved with a regional science fair = and have not seen a single seismometer project. The closest I have seen = was using a vibration device to measure the ride of an automobile. I = had one highschool teacher who let me operate my Lehman from her = classroom for a couple weeks each year but now she is gone and there is = zero interest in seismology in the area. From where I sit there will = not be any new seismologists to use those last bits of resolution. = Anyone providing a spark of imagination and an avenue of entry for = interested young minds is making a great contribution to seismology or = more broadly science. Earth science is falling out of classroom time in = favor or green and alternative energy. What will give a student more = pride and motivation, connecting a professional device with no = understanding of it or constructing a caveman device and recording a = distant quake? We are up against Facebook and IPhones for kids time and = energy. Randy
Chris,
 
There are also many battles out = here that need=20 fighting in addition to getting the last nanometer resolution = from a=20 homebrew seismometer.  For the past nine years  I have = been=20 involved with a regional science fair and have not seen a single = seismometer=20 project.  The closest I have seen was using a vibration device to = measure=20 the ride of an automobile.  I had one highschool teacher who let me = operate=20 my Lehman from her classroom for a couple weeks each year but now = she is=20 gone and there is zero interest in seismology in the area.  From = where I=20 sit there will not be any new seismologists to use those last bits of=20 resolution.  Anyone providing a spark of imagination and an avenue = of entry=20 for interested young minds is making a great contribution to seismology = or more=20 broadly science.  Earth science is falling out of classroom time in = favor=20 or green and alternative energy.  What will give a student more = pride and=20 motivation,  connecting a professional device with no understanding = of=20 it or constructing a caveman device and recording a distant = quake?  We=20 are up against Facebook and IPhones for kids time and = energy.
 
Randy
Subject: Re: Instrument quality From: "Geoffrey" gmvoeth@........... Date: Mon, 19 Oct 2009 15:03:00 -0700 The area of seismology has a lot of stupid patented stuff that discourages playing around with instrumentation. If you accidentally build a patented device and I mean even one not used by anyone you can not market or mass produce it or anything like that unless the existing patent has expired or so I understand. Or this stupid patent stuff will be the source of a serious law suit. All I know is for the amateur there's nothing better than a simple common machine called a pendulum with a magnet and a coil or solenoid coil a simple common op amp circuit with commercial A/D of some kind ( Guess Larry's already got all that so no one really needs to build it them self) But you should with fair amount of ease be able to detect a 4.0 quake at 6 great circle degrees distance. Just make sure it is >= 1 second period and amplify down to the noise level of +/- two or three counts + and - with the sensor attached on a Sunday night or Monday morning before 4 AM. For me a typical DC gain of X10,000 at one hertz. This is all typical which is not exact and precise like scientist fellows prefer. But then we are amateurs and only do this for fun. Were not trying to hear our neighbors next door through the ground like those CIA fellows like to do. ----- Original Message ----- From: "Randy Pratt" To: Sent: Monday, October 19, 2009 8:43 AM Subject: Instrument quality Chris, There are also many battles out here that need fighting in addition to getting the last nanometer resolution from a homebrew seismometer. For the past nine years I have been involved with a regional science fair and have not seen a single seismometer project. The closest I have seen was using a vibration device to measure the ride of an automobile. I had one highschool teacher who let me operate my Lehman from her classroom for a couple weeks each year but now she is gone and there is zero interest in seismology in the area. From where I sit there will not be any new seismologists to use those last bits of resolution. Anyone providing a spark of imagination and an avenue of entry for interested young minds is making a great contribution to seismology or more broadly science. Earth science is falling out of classroom time in favor or green and alternative energy. What will give a student more pride and motivation, connecting a professional device with no understanding of it or constructing a caveman device and recording a distant quake? We are up against Facebook and IPhones for kids time and energy. Randy __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Instrument quality From: ChrisAtUpw@....... Date: Mon, 19 Oct 2009 21:09:59 EDT In a message dated 19/10/2009, gmvoeth@........... writes: If you accidentally build a patented device and I mean even one not used by anyone you can not market or mass produce it or anything like that unless the existing patent has expired or so I understand. Hi Geoff, The Wood Anderson patent, if there was one, would have run out over 50 years ago. Unfortunately, this modification seems to suffer from a string of design flaws. Regards, Chris.
In a message dated 19/10/2009, gmvoeth@........... writes:
If you=20 accidentally build a patented device and I mean even one not used by any= one=20 you can not market or mass produce it or anything like that unless the= =20 existing patent has expired or so
I understand.
Hi Geoff,
 
    The Wood Anderson patent, if there was one,= would=20 have run out over 50 years ago.
    Unfortunately, this modification seems to suf= fer=20 from a string of design flaws.  
    
    Regards,
 
    Chris.
Subject: instrument design From: Randall Peters PETERS_RD@.......... Date: Tue, 20 Oct 2009 10:12:03 -0400 After following recent discussions concerned with the tradeoffs= that regulate seismometer performance, I decided to offer the following. = Just as Chris has years of significant experience concerned with one of the= two primarily critical factors (electronics), so my physics research for m= ore than two decades has been focused on the other one of these two factors= (mechanical properties, especially 'imperfections'). It is the property o= f real (structural) materials (imperfections associated with creep) that mo= tivated the development of the professional standard of force feedback (rel= atively complicated electronics). Why are the mechanical challenges so important? The answer has= to do with instrument sensitivity. For a 'pure' pendulum, the sensitivity= is proportional to the square of its natural period. If one could readily= make an ideal simple pendulum with a period of 10 s (very long indeed), it= s ability to detect earthquakes would be a hundred times that of a pendulum= having a period of 1 s. It must be understood, however, that period lengt= hening (though necessary) is not a sufficient condition for improved (horiz= ontal) acceleration sensitivity. It accomplishes nothing (for conventional= seismology purposes) when the means for period lengthening involves moving= the center of mass close to the axis of rotation. Such a device can be us= ed for measuring rotational effects of an earthquake, but that is not yet a= part of routine amateur studies. To appreciate what I've just said, take = a uniform stick (such as a meter sick) and hold it vertical with forefinger= and thumb just above its center (functioning as a physical pendulum). Rot= ating the stick away from vertical by pushing with the other hand at the to= p (or bottom), you will see that it can oscillate with a longer period than= a string/bob (simple pendulum) of the same length. Now laterally (horizon= tally) accelerate your hand holding the stick and you will see that there i= s no rotation of the stick whatsoever as your hold-point approaches the sti= ck-center. If creep were not an issue, this system would have zero (conven= tional) earthquake sensitivity even as its period approaches infinity! For= those who want a math-treatment of what I've just described, I can give yo= u a copy of the invited tutorial that I wrote for the BSSA Special issue co= ncerned with rotation, titled "Tutorial on gravitational pendulum theory ap= plied to seismic sensing of translation and rotation". http://www.bssaonlin= e.org/cgi/content/abstract/99/2B/1050 So what should be the primary concern of amateur seismologists.= I believe that more critical thought concerning mechanical properties is = again called for. With such thought the need exists to dispense with 'blin= ders' associated with specific (previous) individual failures to achieve pe= rformance levels that were being sought. For example, most everybody has d= eparted from the use of viscous damping in favor of powerful rare earth mag= nets, functioning by means of induced eddy currents in highly conductive (c= opper) plates. I believe there is merit to the consideration of both uncon= ventional magnet use coupled with a viscous fluid to provide both damping a= nd also buoyancy for period lengthening; which I now describe. In the paper that John Lee and I wrote (mouse sensor for pendu= lum measurements), arxiv.org/html/0904.3070 one will find measurements in which a magnet was used with a ball-point pen= to support the pendulum, while providing a low-friction axis of rotation. = The magnet/pen-point is responsible for a 'destoring' force (away from ver= tical equilibrium), whereas gravity provides a 'restoring' force (torque to= ward vertical when disturbed). The torques from the two act in opposition = to one another, so there is a period lengthening that is beneficial. A commercial horizontal seismometer that successfully uses the = same physical principle is the Kinemetrics SH-1. The torque acting in oppo= sition to gravity is provided by means of a vertical elastic metal strip (s= pring) that holds the seismic mass in an equilibrium position directly abov= e it. The instrument employs two magnet/coil subsystems: (i) one for Farad= ay law detection with which every amateur seismologist is familiar, and the= (ii) other one for calibration (by introducing a current to the coil) and = for damping when operational (by placing a resistor across the coil). What I propose for some of you to experiment with is the follow= ing. Use my magnet/ball-pen for top support and a viscous fluid (such as m= ineral oil) for the 'bob' at the bottom to move in. If the bob is suitably= shaped, and if the amount of its submersion is judiciously chosen, then it= should be possible to get period lengthening of beneficial type from both = the fluid and the pen/magnet. The fluid will serve two purposes, to assist= the magnet in period lengthening and to also provide damping. As the period gets longer, such systems are increasingly sensit= ive to pendulum-structure variations. In other words, just as the sensitiv= ity to an ideal pendulum is proportional to the square of the period, so th= e adverse sensitivity of a non-ideal pendulum to the influence of its struc= tural imperfections. Without some means to minimize the influence of imper= fections, the tendency for the system to 'creep to the mechanical rails' in= creases dramatically as the period lengthens. The conventional means for o= vercoming this creep is to use electronic-based force feedback with a magne= t/coil actuator. I believe, however, that amateur experimentation might di= scover a bob shape with useful liquid-buoyancy (like that of a properly de= signed hull of a ship that is stable rather than unstable). If so, it shou= ld greatly facilitate keeping the pendulum in an operational position. I have not here mentioned sensor type. For those with interest= I can offer thoughts based on my long-time experience with both velocity a= nd position types. Randall Peters

       = ;     After following recent discussions concerned with the tradeoffs that regulate seismometer performance, I decided to offer the following.  Just as Ch= ris has years of significant experience concerned with one of the two primarily critical factors (electronics), so my physics research for more than two decades has been focused on the other one of these two factors (mechanical properties, especially 'imperfections').  It is the property of real (structural) materials (imperfections associated with creep) that motivated= the development of the professional standard of force feedback (relatively complicated electronics). 

       = ;     Why are the mechanical challenges so important?  The answer has to do with instrument sensitivity.  For a 'pure' pendulum, the sensitivity is pro= portional to the square of its natural period.  If one could readily make an ide= al simple pendulum with a period of 10 s (very long indeed), its ability to de= tect earthquakes would be a hundred times that of a pendulum having a period of = 1 s.  It must be understood, however, that period lengthening (though necessary) = is not a sufficient condition for improved (horizontal) acceleration sensitivity.  It accomplishes nothing (for conventional seismology purposes) when the means for period lengthening involves moving the center = of mass close to the axis of rotation.  Such a device can be used for measuring rotational effects of an earthquake, but that is not yet a part o= f routine amateur studies.  To appreciate what I've just said, take a uniform stick (such as a meter sick) and hold it vertical with forefinger a= nd thumb just above its center (functioning as a physical pendulum).  Rotating the stick away from vertical by pushing with the other hand at the= top (or bottom), you will see that it can oscillate with a longer period than a string/bob (simple pendulum) of the same length.  Now laterally (horizontally) accelerate your hand holding the stick and you will see that there is no rotation of the stick whatsoever as your hold-point approaches = the stick-center.  If creep were not an issue, this system would have zero (conventional) earthquake sensitivity even as its period approaches infinity!  For those who want a math-treatment of what I've just described, I can give you a copy of the invited tutorial that I wrote for t= he BSSA Special issue concerned with rotation, titled "Tutorial on gravitational pendulum theory applied to seismic sensing of translation and rotation". http://www.bssaonline.org/cgi/content/abstract/99/2B/1050

       = ;     So what should be the primary concern of amateur seismologists.  I believ= e that more critical thought concerning mechanical properties is again called for.  With such thought the need exists to dispense with 'blinders' associated with specific (previous) individual failures to achieve performa= nce levels that were being sought.  For example, most everybody has depart= ed from the use of viscous damping in favor of powerful rare earth magnets, functioning by means of induced eddy currents in highly conductive (copper) plates.  I believe there is merit to the consideration of both unconve= ntional magnet use coupled with a viscous fluid to provide both damping and also buoyancy for period lengthening; which I now describe.

       = ;      In the paper that John Lee and I wrote (mouse sensor for pendulum measurements= ), arxiv.org/html/0904.3070

one will find measurements in which a mag= net was used with a ball-point pen to support the pendulum, while providing a low-friction axis of rotation.  The magnet/pen-point is responsible fo= r a 'destoring' force (away from vertical equilibrium), whereas gravity provide= s a 'restoring' force (torque toward vertical when disturbed).  The torque= s from the two act in opposition to one another, so there is a period lengthe= ning that is beneficial.

       = ;     A commercial horizontal seismometer that successfully uses the same physical principle is the Kinemetrics SH-1.  The torque acting in opposition to gravity is provided by means of a vertical elastic metal strip (spring) tha= t holds the seismic mass in an equilibrium position directly above it.  = The instrument employs two magnet/coil subsystems: (i) one for Faraday law dete= ction with which every amateur seismologist is familiar, and the (ii) other one f= or calibration (by introducing a current to the coil) and for damping when operational (by placing a resistor across the coil).

       = ;     What I propose for some of you to experiment with is the following.  Use my magnet/ball-pen for top support and a viscous fluid (such as mineral oil) f= or the 'bob' at the bottom to move in.  If the bob is suitably shaped, an= d if the amount of its submersion is judiciously chosen, then it should be possi= ble to get period lengthening of beneficial type from both the fluid and the pen/magnet.  The fluid will serve two purposes, to assist the magnet i= n period lengthening and to also provide damping. 

          &nb= sp; As the period gets longer, such systems are increasingly sensitive to pendulum-structure variations.  In other words, just as the sensitivit= y to an ideal pendulum is proportional to the square of the period, so the adver= se sensitivity of a non-ideal pendulum to the influence of its structural imperfections.  Without some means to minimize the influence of imperfections, the tendency for the system to 'creep to the mechanical rail= s' increases dramatically as the period lengthens.  The conventional mean= s for overcoming this creep is to use electronic-based force feedback with a magnet/coil actuator.  I believe, however, that amateur experimentatio= n might discover a bob shape with useful liquid-buoyancy  (like that of = a properly designed hull of a ship that is stable rather than unstable). = ; If so, it should greatly facilitate keeping the pendulum in an operational position.

          &nb= sp; I have not here mentioned sensor type.  For those with interest I can of= fer thoughts based on my long-time experience with both velocity and position types. 

    Randall Peters

 

Subject: RE: Instrument quality From: "Gary Lindgren" gel@................. Date: Tue, 20 Oct 2009 11:53:38 -0700 Randy, I know what you mean about not much interest with the younger set and seismology. This past summer I attended the Bay Area Maker Faire. I thought for sure there would be a few exhibits on what people were doing with seismometers. There several buildings all full of various scientific leaning exhibits. Thousands of people and not one booth on seismometers. I was quite disappointed. Gary From: psn-l-request@.............. [mailto:psn-l-request@............... On Behalf Of Randy Pratt Sent: Monday, October 19, 2009 8:44 AM To: psn-l@.............. Subject: Instrument quality Chris, There are also many battles out here that need fighting in addition to getting the last nanometer resolution from a homebrew seismometer. For the past nine years I have been involved with a regional science fair and have not seen a single seismometer project. The closest I have seen was using a vibration device to measure the ride of an automobile. I had one highschool teacher who let me operate my Lehman from her classroom for a couple weeks each year but now she is gone and there is zero interest in seismology in the area. From where I sit there will not be any new seismologists to use those last bits of resolution. Anyone providing a spark of imagination and an avenue of entry for interested young minds is making a great contribution to seismology or more broadly science. Earth science is falling out of classroom time in favor or green and alternative energy. What will give a student more pride and motivation, connecting a professional device with no understanding of it or constructing a caveman device and recording a distant quake? We are up against Facebook and IPhones for kids time and energy. Randy

Randy,

I know what you mean about not much interest with the = younger set and seismology. This past summer I attended the Bay Area Maker = Faire. I thought for sure there would be a few exhibits on what people were doing = with seismometers. There several buildings all full of various scientific = leaning exhibits. Thousands of people and not one booth on seismometers. I was = quite disappointed.

Gary

 

From:= psn-l-request@.............. [mailto:psn-l-request@............... On = Behalf Of Randy Pratt
Sent: Monday, October 19, 2009 8:44 AM
To: psn-l@..............
Subject: Instrument quality

 

Chris,=

 

There are also many battles out here that need fighting in addition to getting the last nanometer resolution from a homebrew seismometer.  For the past nine years  I have been = involved with a regional science fair and have not seen a single seismometer = project.  The closest I have seen was using a vibration device to measure the ride = of an automobile.  I had one highschool teacher who let me operate my = Lehman from her classroom for a couple weeks each year but now she is gone = and there is zero interest in seismology in the area.  From where I sit = there will not be any new seismologists to use those last bits of = resolution.  Anyone providing a spark of imagination and an avenue of entry for = interested young minds is making a great contribution to seismology or more broadly science.  Earth science is falling out of classroom time in favor = or green and alternative energy.  What will give a student more pride and = motivation,  connecting a professional device with no understanding of it or constructing a caveman device and recording a distant quake?  We = are up against Facebook and IPhones for kids time and = energy.

 

Randy<= o:p>

Subject: Re: Instrument quality From: ChrisAtUpw@....... Date: Wed, 21 Oct 2009 18:10:33 EDT In a message dated 19/10/2009, rpratt@............. writes: There are also many battles out here that need fighting in addition to getting the last nanometre resolution from a home-brew seismometer. Hi Randy, Thanks for the feedback and for your different perspective. Sure, but my Email was not primarily concerned with trying to get the last nanometre of sensitivity, but with whether the thing works at all ! Will the detection of only one earthquake a MONTH, when it could and should be several every WEEK, either spark or maintain any significant interest in any of your kids? This seems more than a bit unlikely to me. And encouraging someone to make a considerable effort to build equipment which then doesn't work will definitely kill off ANY interest ! Quote: "Do your homework! A lot of folks out there have already done this, save yourself time, effort, and money by doing some research." So what 'fruits' of caveman's 'research' seem have actually made it through to the design? A very noisy, non linear photo detector was chosen A highly temperature dependant photo emitter was chosen The excitation current was neither stabilised nor temperature compensated A single ended electronic construction was chosen, which does not reduce any common mode effects A multi filament suspension was chosen No details of how to design the sensor to match the frequency range of seismic signals seems to be given No details of how to design and adjust the damper to give 0.7 critical damping seems to be given Getting adequate seismic detection sensitivity is not normally a problem with optical, electromagnetic, magnetic or capacitor sensors, in my experience. I welcome equipment and suggestions which work. Note that caveman had detailed drawings of a Wood Anderson seismometer available to copy / inspire him. Richter used several WA seismometers to develop his Earthquake Magnitude Scale in 1935, so we can assume that they worked reasonably well. For the past nine years I have been involved with a regional science fair and have not seen a single seismometer project. So, having identified one of the problems, can YOU help correct it, please? Is this simply because the students download a list of project suggestions and seismometers are just not on it? Provide information sources and design help? Maybe publicise some seismic projects which actually DO work? Put them on psn? I had one highschool teacher who let me operate my Lehman from her classroom for a couple weeks each year but now she is gone and there is zero interest in seismology in the area. From where I sit there will not be any new seismologists to use those last bits of resolution. How have you been trying to get kids interested in Seismology? Anyone providing a spark of imagination and an avenue of entry for interested young minds is making a great contribution to seismology or more broadly science. Earth science is falling out of classroom time in favour or green and alternative energy. NOT around OUR neck of the woods!! A good quality working Lehman was designed for schools and marketed from Easter 2007. Sales since then have exceeded 400 systems. This is a successful project and we expand further into Europe next year. See _http://www.bgs.ac.uk/schoolseismology/_ (http://www.bgs.ac.uk/schoolseismology/) and click on 'Seismometers'. Remember that we have just 1/5 the population of the USA. I would be quite happy to pass on some details of the design. There is a handbook on the website. There is considerable enthusiasm amongst our pupils for 'Real Science with Real Seismic Signals'. It is 'their' seismometer and small interested groups run it, analyse the quakes with help from AmaSeis, plot them on a world map and keep records. They also get considerable credit for having done a practical scientific project when they apply for a place at University. What will give a student more pride and motivation, connecting a professional device with no understanding of it or constructing a caveman device and recording a distant quake? We are up against Facebook and IPhones for kids time and energy. Randy What professional devices are you considering? Are you suggesting that it is not possible to make a good quality DIY seismometer? Where is the evidence that the caveman device can give an even marginally adequate performance? One quake a month (maybe) will not provide much competition for Facebook or an IPhone, but it might generate a few Twitters. A few years back, I helped one of your students with his seismic project - very long range help! We discussed the design requirements, principles and details. He had a friend helping with some machining, but made the design choices himself. He produced a good working seismometer and a full written account, complete with recordings of quakes and comparison records from a local broad band seismometer. They were almost identical. He entered this in a Science Fair and won a First Prize. You need many more like him. What you do seem to be lacking in the USA is an inexpensive school seismometer responding flat with velocity from about 5 Hz to 20 seconds. The response must be independant of temperature. It must be easy to set up and operate. Iris seem to be insisting on a vertical sensor. It would be preferable if it was compensated for variations in air pressure, since these are the predominant source of sensor noise. What do you suggest? Regards, Chris Chapman
In a message dated 19/10/2009, rpratt@............. writes:
There are also many battles out he= re that=20 need fighting in addition to getting the last nanometre resolu= tion=20 from a home-brew seismometer.  
Hi Randy,
 
    Thanks for the feedback and for your differen= t=20 perspective.
 
    Sure, but my Email was not primarily concerne= d with=20 trying to get the last nanometre of sensitivity, but with whether the thin= g=20 works at all !
 
    Will the detection of only one earthquake a= MONTH,=20 when it could and should be several every WEEK, either spark or= =20 maintain any significant interest in any of your kids? This seems more tha= n a=20 bit unlikely to me.
 
    And encouraging someone to make a considerabl= e=20 effort to build equipment which then doesn't work will definitely kill=20 off ANY interest !
 
Quote: "Do your homework! A lot of folks out there have already done= this,=20 save yourself time, effort, and money by doing some research."
 
    So what 'fruits' of caveman's 'research'= seem=20 have actually made it through to the design?
 
    A very noisy, non linear photo detector was= =20 chosen
    A highly temperature dependant photo emitter= was=20 chosen The excitation current was neither stabilised nor temperature=20 compensated
    A single ended electronic construction was ch= osen,=20 which does not reduce any common mode effects
    A multi filament suspension was chosen
    No details of how to design the sensor to mat= ch the=20 frequency range of seismic signals seems to be given
    No details of how to design and adjust= the=20 damper to give 0.7 critical damping seems to be given
 
    Getting adequate seismic detection=20 sensitivity is not normally a problem with optical, electromagne= tic,=20 magnetic or capacitor sensors, in my experience. I welcome equipment and= =20 suggestions which work.
 
    Note that caveman had detailed drawings of a= Wood=20 Anderson seismometer available to copy / inspire him. Richter used several= WA=20 seismometers to develop his Earthquake Magnitude Scale in 1935, so we can= assume=20 that they worked reasonably well.
For the past nine years I have= been=20 involved with a regional science fair and have not seen a single seismom= eter=20 project.  
    So, having identified one of the problems,=20 can YOU help correct it, please? Is this simply because the stud= ents=20 download a list of project suggestions and seismometers are just not= on it?=20 Provide information sources and design help? Maybe publicise som= e=20 seismic projects which actually DO work? Put them on psn?
 
   I had one highschool tea= cher who let=20 me operate my Lehman from her classroom for a couple weeks each year = but=20 now she is gone and there is zero interest in seismology in the area. From= where=20 I sit there will not be any new seismologists to use those last bits of=20 resolution. 
 
    How have you been trying to get kids interest= ed in=20 Seismology?
Anyone providing a spark of ima= gination and=20 an avenue of entry for interested young minds is making a great contribu= tion=20 to seismology or more broadly science.  Earth science is falling ou= t of=20 classroom time in favour or green and alternative energy. =20
    NOT around OUR neck of the woods!! A goo= d=20 quality working Lehman was designed for schools and marketed from Easter= 2007.=20 Sales since then have exceeded 400 systems. This is a successful project= and=20 we expand further into Europe next year. See http://www.bgs.ac.uk/schoo= lseismology/  and=20 click on 'Seismometers'.
    Remember that we have just 1/5 the population= of=20 the USA.
    I would be quite happy to pass on some detail= s of=20 the design. There is a handbook on the website. There is considerable enth= usiasm=20 amongst our pupils for 'Real Science with Real Seismic Signals'. It is 'th= eir'=20 seismometer and small interested groups run it, analyse the quakes with he= lp=20 from AmaSeis, plot them on a world map and keep records. They also ge= t=20 considerable credit for having done a practical scientific project wh= en=20 they apply for a place at University. 
What will give a student more= pride and=20 motivation, connecting a professional device with no understanding= of=20 it or constructing a caveman device and recording a distant quake?&= nbsp;=20 We are up against Facebook and IPhones for kids time and energy.<= /DIV>
Randy
    What professional devices are you considering= ?=20
    Are you suggesting that it is not possib= le to=20 make a good quality DIY seismometer?
    Where is the evidence that the cave= man=20 device can give an even marginally adequate performance?
    One quake a month (maybe) will not provide mu= ch=20 competition for Facebook or an IPhone, but it might generate a= =20 few Twitters. 
 
    A few years back, I helped one of your studen= ts=20 with his seismic project - very long range help! We discussed the design= =20 requirements, principles and details. He had a friend helping with some=20 machining, but made the design choices himself. He produced a good wo= rking=20 seismometer and a full written account, complete with recordings of= quakes=20 and comparison records from a local broad band seismometer. They were almo= st=20 identical. He entered this in a Science Fair and won a First Prize.=
    You need many more like him.
 
    What you do seem to be lacking in the USA is= an=20 inexpensive school seismometer responding flat with velocity from about 5= Hz to=20 20 seconds. The response must be independant of temperature. It must be ea= sy to=20 set up and operate. Iris seem to be insisting on a vertical sensor.= It=20 would be preferable if it was compensated for variations in air pressure,= since=20 these are the predominant source of sensor noise.
    What do you suggest? 
    
    Regards,
 
    Chris Chapman
Subject: Re: Instrument quality - microseisms From: Barry Lotz barry_lotz@............. Date: Wed, 21 Oct 2009 18:57:59 -0700 (PDT) To all Related to instrument quality- maybe. I have noticed a lot more microseismi= c activity the last few days. The background noise on my vertical is around= +/- 300 counts @=A0 8.7 sec=A0 and 6.6 sec=A0 (two narrow peaks). I don't = remember this magnitude in years past. I'm sure it is weather related. I li= ve about 200 miles east of the west coast of northern California. Anyone el= se noticed an increase in background lately? Every time I look at the outpu= t I think I'm looking at surface waves after an event. Barry

To all
Related to instrument quality- = maybe. I have noticed a lot more microseismic activity the last few days. T= he background noise on my vertical is around +/- 300 counts @  8.7 sec=   and 6.6 sec  (two narrow peaks). I don't remember this magnitud= e in years past. I'm sure it is weather related. I live about 200 miles eas= t of the west coast of northern California. Anyone else noticed an increase= in background lately? Every time I look at the output I think I'm looking = at surface waves after an event.
Barry

Subject: Re: Instrument quality - microseisms From: "GPayton" gpayton@............. Date: Wed, 21 Oct 2009 21:07:17 -0500 Look at the src.psn post on http://www.seismicnet.com/cgi-dos/event.exe regarding "Sneaker Waves." Being a city boy from Northern Texas, I had never heard of "Sneaker Waves." Interesting information through Google. Also, being ex-Navy, I has visions of U.S. Navy "Waves" wearing tennis shoes! Wrong. Regards, Jerry ----- Original Message ----- From: Barry Lotz To: psn-l@.............. Sent: Wednesday, October 21, 2009 8:57 PM Subject: Re: Instrument quality - microseisms To all Related to instrument quality- maybe. I have noticed a lot more microseismic activity the last few days. The background noise on my vertical is around +/- 300 counts @ 8.7 sec and 6.6 sec (two narrow peaks). I don't remember this magnitude in years past. I'm sure it is weather related. I live about 200 miles east of the west coast of northern California. Anyone else noticed an increase in background lately? Every time I look at the output I think I'm looking at surface waves after an event. Barry
Look at the src.psn post on  http://www.seismicne= t.com/cgi-dos/event.exe =20 regarding "Sneaker Waves."
 
Being a city boy from Northern Texas, I had = never heard of=20 "Sneaker Waves."  Interesting information through Google.  = Also, being=20 ex-Navy, I has visions of U.S. Navy "Waves" wearing tennis shoes! =20 Wrong.
 
Regards,
Jerry
----- Original Message -----
From:=20 Barry=20 Lotz
Sent: Wednesday, October 21, = 2009 8:57=20 PM
Subject: Re: Instrument quality = -=20 microseisms


To all
Related to instrument quality- = maybe. I=20 have noticed a lot more microseismic activity the last few days. = The=20 background noise on my vertical is around +/- 300 counts @  = 8.7=20 sec  and 6.6 sec  (two narrow peaks). I don't remember = this=20 magnitude in years past. I'm sure it is weather related. I live = about=20 200 miles east of the west coast of northern California. Anyone = else=20 noticed an increase in background lately? Every time I look at = the=20 output I think I'm looking at surface waves after an=20 = event.
Barry

Subject: Re: Instrument quality - microseisms From: meredith lamb paleoartifact@......... Date: Wed, 21 Oct 2009 20:37:01 -0600 Probably the current tropical storm "Rick", off the west coast of Mexico which was downgraded from hurrican status. Meredith On Wed, Oct 21, 2009 at 7:57 PM, Barry Lotz wrote: > > To all > Related to instrument quality- maybe. I have noticed a lot more > microseismic activity the last few days. The background noise on my vertical > is around +/- 300 counts @ 8.7 sec and 6.6 sec (two narrow peaks). I > don't remember this magnitude in years past. I'm sure it is weather related. > I live about 200 miles east of the west coast of northern California. Anyone > else noticed an increase in background lately? Every time I look at the > output I think I'm looking at surface waves after an event. > Barry > >
Probably the current tropical storm "Rick", off the west coa= st of Mexico which was downgraded
from hurrican status.

Meredith
On Wed, Oct 21, 2009 at 7:57 PM, Barry Lotz <barry_lotz@sb= cglobal.net> wrote:

To all
Related to instrument quality- maybe. I ha= ve noticed a lot more microseismic activity the last few days. The backgrou= nd noise on my vertical is around +/- 300 counts @=A0 8.7 sec=A0 and 6.6 se= c=A0 (two narrow peaks). I don't remember this magnitude in years past.= I'm sure it is weather related. I live about 200 miles east of the wes= t coast of northern California. Anyone else noticed an increase in backgrou= nd lately? Every time I look at the output I think I'm looking at surfa= ce waves after an event.
Barry


Subject: Re: instrument design From: meredith lamb paleoartifact@......... Date: Wed, 21 Oct 2009 20:56:29 -0600 On Tue, Oct 20, 2009 at 8:12 AM, Randall Peters wrote: (Clip) Randall, ** In regard to the Kinemetrics SH-1; I'am having difficulty visualizing the spring directlyabove the horizontal pendulum mass. Might you and anyone have a PDF file with a picture/s they could share? > A commercial horizontal seismometer that successfully uses > the same physical principle is the Kinemetrics SH-1. The torque acting in > opposition to gravity is provided by means of a vertical elastic metal strip > (spring) that holds the seismic mass in an equilibrium position directly > above it. The instrument employs two magnet/coil subsystems: (i) one for > Faraday law detection with which every amateur seismologist is familiar, and > the (ii) other one for calibration (by introducing a current to the coil) > and for damping when operational (by placing a resistor across the coil). > > ** Feel free to offer your thoughts on the sensors. > I hae not here mentioned sensor type. For those with interest I can offer > thoughts based on my long-time experience with both velocity and position > types. > > Randall Peters > Meredith Lamb > >

On Tue, Oct 20, 2009 at 8:12 AM, Randall Peters = <PETERS_RD@mer= cer.edu> wrote:
=A0
(Clip)
=A0
Randall,
=A0
** In regard to the Kinemetrics SH-1; I'am h= aving difficulty visualizing the spring directlyabove the
horizontal pendulum mass.=A0 Might you and anyon= e have a PDF file with a picture/s they could share?

=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0 A commercial horizo= ntal seismometer that successfully uses the same physical principle is the = Kinemetrics SH-1.=A0 The torque acting in opposition to gravity is provided= by means of a vertical elastic metal strip (spring) that holds the seismic= mass in an equilibrium position directly above it.=A0 The instrument emplo= ys two magnet/coil subsystems: (i) one for Faraday law detection with which= every amateur seismologist is familiar, and the (ii) other one for calibra= tion (by introducing a current to the coil) and for damping when operationa= l (by placing a resistor across the coil).

** Feel free to offe= r your thoughts on the sensors.

I hae not here me= ntioned sensor type.=A0 For those with interest I can offer thoughts based = on my long-time experience with both velocity and position types.=A0

Randall Peters=A0=A0=

=A0
Meredith Lamb
=A0
Subject: Re: Instrument quality - microseisms From: Stephen & Kathy skmort@............ Date: Wed, 21 Oct 2009 20:53:13 -0700 Hi Barry, I'm a little south of you...   I also have increased noise.  Whenever I see this kind of noise, I check with Berkeley at:
http://quake.geo.berkeley.edu/bdsn/make_seismogram.html

If you just create plot without setting time, it will create todays seismogram for CMB... I use 4 for compression to get an hour per line;  and pixels at 25 to get a little separation.  Sorry if I am sharing old info...   if so, maybe it will help others?

If you check the following ocean weather link you will see why...  there are 20 to 25 foot waves off the NW USA coast.   Earlier, they were showing up to 30 foot waves. You can click on any box to see the conditions in the box...  I click on the box that shows Alaska to below Baja...   and yes, the energy is apparently coming from 200 to 400 miles away:
http://www.oceanweather.com/data/

At one time I had my gain so high that noise like this would set off my alarm, (I have a separate alarm, which I built before I had a computer and recording capability).
  Stephen
  PSN Station #55
  38.828N  120.979W
  near Pilot Hill Calif  

Barry Lotz wrote:

To all
Related to instrument quality- maybe. I have noticed a lot more microseismic activity the last few days. The background noise on my vertical is around +/- 300 counts @  8.7 sec  and 6.6 sec  (two narrow peaks). I don't remember this magnitude in years past. I'm sure it is weather related. I live about 200 miles east of the west coast of northern California. Anyone else noticed an increase in background lately? Every time I look at the output I think I'm looking at surface waves after an event.
Barry
Subject: Re: Instrument quality - microseisms<<< GOOD INFO >>>> From: "Jim ODonnell" geophysics@.......... Date: Thu, 22 Oct 2009 04:43:01 GMT Thank-You Stephen as that IS VERY USEFUL INFORMATION...... Jim Jim O'Donnell- Geophysical Consultant/Contractor Geotechnical/Geothermal/Oil & Gas/Mining Applications Seismic Surveys- Surface Waves, Refraction, & Reflection Ground Penetrating Radar, Resistivity, Magnetic, & VLF-EM Surveys Geophysics@.......... 702.293.5664 702.281.9081 cell = Boulder City, NV ---------- Original Message ---------- From: Stephen & Kathy To: psn-l@.............. Subject: Re: Instrument quality - microseisms Date: Wed, 21 Oct 2009 20:53:13 -0700 Hi Barry, I'm a little south of you... I also have increased noise. W= henever I see this kind of noise, I check with Berkeley at: http://quake.geo.berkeley.edu/bdsn/make_seismogram.html If you just create plot without setting time, it will create todays seis= mogram for CMB... I use 4 for compression to get an hour per line; and = pixels at 25 to get a little separation. Sorry if I am sharing old info= .... if so, maybe it will help others? = If you check the following ocean weather link you will see why... there= are 20 to 25 foot waves off the NW USA coast. Earlier, they were show= ing up to 30 foot waves. You can click on any box to see the conditions = in the box... I click on the box that shows Alaska to below Baja... a= nd yes, the energy is apparently coming from 200 to 400 miles away: http://www.oceanweather.com/data/ At one time I had my gain so high that noise like this would set off my = alarm, (I have a separate alarm, which I built before I had a computer a= nd recording capability). Stephen PSN Station #55 38.828N 120.979W near Pilot Hill Calif = Barry Lotz wrote: = To all Related to instrument quality- maybe. I have noticed a lot more microsei= smic activity the last few days. The background noise on my vertical is = around +/- 300 counts @ 8.7 sec and 6.6 sec (two narrow peaks). I don= 't remember this magnitude in years past. I'm sure it is weather related= .. I live about 200 miles east of the west coast of northern California. = Anyone else noticed an increase in background lately? Every time I look = at the output I think I'm looking at surface waves after an event. Barry Thank-You Stephen as that IS VERY USEFUL INFORMATION......&nb= sp;  Jim


Jim O'Donnell- Geophysical Consultant/Cont= ractor
Geotechnical/Geothermal/Oil & Gas/Mining Applications
S= eismic Surveys- Surface Waves, Refraction, & Reflection
Ground Pe= netrating Radar, Resistivity, Magnetic, & VLF-EM Surveys
Geophysi= cs@..........  702.293.5664  702.281.9081 cell   Boulder City, NV


---------- Original Message ----------
F= rom: Stephen & Kathy <skmort@............>
To: psn-l@webtro= nics.com
Subject: Re: Instrument quality - microseisms
Date: Wed, = 21 Oct 2009 20:53:13 -0700

Hi Barry, I'm a li= ttle south of you...   I also have increased noise.  When= ever I see this kind of noise, I check with Berkeley at:
http://quake.geo.berkeley.edu/bdsn/make_seismogram.html

If you just create plot without setting time, it will create to= days seismogram for CMB... I use 4 for compression to get an hour per li= ne;  and pixels at 25 to get a little separation.  Sorry if I = am sharing old info...   if so, maybe it will help others?
If you check the following ocean weather link you will see why...&n= bsp; there are 20 to 25 foot waves off the NW USA coast.   Ear= lier, they were showing up to 30 foot waves. You can click on any box to= see the conditions in the box...  I click on the box that shows Al= aska to below Baja...   and yes, the energy is apparently comi= ng from 200 to 400 miles away:
http://www.oceanweather.com/data/

At one time I had my gain so high that noise like this would se= t off my alarm, (I have a separate alarm, which I built before I had a c= omputer and recording capability).
  Stephen
  PSN Stati= on #55
  38.828N  120.979W
  near Pilot Hill Calif =  

Barry Lotz wrote: =
<= /TR>

To all
Related to instrument quality- m= aybe. I have noticed a lot more microseismic activity the last few days.= The background noise on my vertical is around +/- 300 counts @  8.= 7 sec  and 6.6 sec  (two narrow peaks). I don't remember this = magnitude in years past. I'm sure it is weather related. I live about 20= 0 miles east of the west coast of northern California. Anyone else notic= ed an increase in background lately? Every time I look at the output I t= hink I'm looking at surface waves after an event.
Barry

Subject: Re: Instrument quality - microseisms From: Barry Lotz barry_lotz@............. Date: Thu, 22 Oct 2009 06:02:19 -0700 (PDT) Stephen Thanks very much - also. Barry --- On Wed, 10/21/09, Stephen & Kathy wrote: From: Stephen & Kathy Subject: Re: Instrument quality - microseisms To: psn-l@.............. Date: Wednesday, October 21, 2009, 8:53 PM =0A=0A=0A =0A =0AHi Barry, I'm a little south of you...=A0=A0 I also=0Aha= ve increased noise.=A0 Whenever I see this kind of noise, I check with=0ABe= rkeley at: =0Ahttp://quake.geo.berkeley.edu/bdsn/make_seismogram.html =0A =0AIf you just create plot without setting time, it will create todays=0Ase= ismogram for CMB... I use 4 for compression to get an hour per line;=A0=0Aa= nd pixels at 25 to get a little separation.=A0 Sorry if I am sharing old=0A= info...=A0=A0 if so, maybe it will help others?=20 =0A =0AIf you check the following ocean weather link you will see why...=A0=0At= here are 20 to 25 foot waves off the NW USA coast.=A0=A0 Earlier, they=0Awe= re showing up to 30 foot waves. You can click on any box to see the=0Acondi= tions in the box...=A0 I click on the box that shows Alaska to below=0ABaja= ....=A0=A0 and yes, the energy is apparently coming from 200 to 400=0Amiles = away: =0Ahttp://www.oceanweather.com/data/ =0A =0AAt one time I had my gain so high that noise like this would set off my= =0Aalarm, (I have a separate alarm, which I built before I had a computer= =0Aand recording capability). =0A=A0 Stephen =0A=A0 PSN Station #55 =0A=A0 38.828N=A0 120.979W =0A=A0 near Pilot Hill Calif =A0=20 =0A =0ABarry Lotz wrote:=0A=0A =0A =0A =0A =20 =0ATo all =0ARelated to instrument quality- maybe. I have noticed a lot more=0Amicros= eismic activity the last few days. The background noise on my=0Avertical is= around +/- 300 counts @=A0 8.7 sec=A0 and 6.6 sec=A0 (two narrow=0Apeaks).= I don't remember this magnitude in years past. I'm sure it is=0Aweather re= lated. I live about 200 miles east of the west coast of=0Anorthern Californ= ia. Anyone else noticed an increase in background=0Alately? Every time I lo= ok at the output I think I'm looking at surface=0Awaves after an event. =0ABarry =0A =20 =0A =0A =0A =0A =0A=0A =0A Subject: Re: Instrument quality - microseisms From: Larry Conklin lconklin@............ Date: Thu, 22 Oct 2009 10:11:31 -0400 My experience has been that around this time of year the microseisms have a tendency to turn into "megaseisms". They can get so strong that they pretty much obscure the P/S arrivals of all but the strongest events. I live in central New York, so I customarily compare my data with the Lamont-Doherty 24 hour helicorder at http://www.ldeo.columbia.edu/cgi-bin/LCSN/WebSeis/24hr_heli.pl When I am getting clobbered, they typically are too. Interestingly, and I can't quantify it, the rise and fall of the strength of the noise seems to be offset by an hour of two between their data an mine. I can't think of a plausible explanation, other than I may be imagining it. The other thing I would love to hear an explanation for is why the microseism noise is so narrow band. When it is strong, it looks virtually sinusoidal on the monitor, and an FFT of the data shows a very narrow peak. Does anyone know why that is? Larry Conklin Liverpool, NY __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Instrument quality - microseisms From: Thomas Dick dickthomas01@............. Date: Thu, 22 Oct 2009 09:26:24 -0500 Barry Lotz wrote: > > To all > Related to instrument quality- maybe. I have noticed a lot more > microseismic activity the last few days. The background noise on my > vertical is around +/- 300 counts @ 8.7 sec and 6.6 sec (two narrow > peaks). I don't remember this magnitude in years past. I'm sure it is > weather related. I live about 200 miles east of the west coast of > northern California. Anyone else noticed an increase in background > lately? Every time I look at the output I think I'm looking at surface > waves after an event. > Barry > From about the 9th of October until yesterday, I was getting very strong peaks in the frequency range of .177Hz or period of 6 seconds here in southern Indiana. Today that peak as disappeared and a lesser peak exists at about .142 Hz or period of approximately 7 seconds. It was so strong that I gave up posting earthquakes to the network because they just weren't clear without strong filtering. I, too, looked for a reason; Great Lakes, Gulf of Mexico and both the east and west coast. I could find no real association. I had NO local winds and no serious temperature changes. __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Instrument quality - microseisms From: George Bush ke6pxp@....... Date: Thu, 22 Oct 2009 09:35:10 -0700 Hi- I uploaded the files on Sneaker waves, sorry that I didn't identify where they were from. Whenever I see this pattern I send a notification out on our local email list so the people along the coast up here North of San Francisco will be careful near the water. I made the upload so that local folks could see what the seismic signal from two storms causing beat patterns in the incoming waves and causing quiet periods where the waves are out of phase and then when they get in phase the BIG waves SNEAK up on you! We have had high surf warnings here and so I am not surprised that the background microseismic activity is high right now. My 24-hour heliplot shows this beat pattern quite clearly, check it out on my website at http://gbush.mcn.org/srn.gif. At 06:57 PM 10/21/2009, you wrote: >To all >Related to instrument quality- maybe. I have noticed a lot more >microseismic activity the last few days. The background noise on my >vertical is around +/- 300 counts @ 8.7 sec and 6.6 sec (two >narrow peaks). I don't remember this magnitude in years past. I'm >sure it is weather related. I live about 200 miles east of the west >coast of northern California. Anyone else noticed an increase in >background lately? Every time I look at the output I think I'm >looking at surface waves after an event. >Barry George Bush Sea Ranch, CA, USA 38.73775N, 123.48882W Hi- I uploaded the files on Sneaker waves, sorry that I didn't identify where they were from.

Whenever I see this pattern I send a notification out on our local email list so the people along the coast up here North of San Francisco will be careful near the water. I made the upload so that local folks could see what the seismic signal from two storms causing beat patterns in the incoming waves and causing quiet periods where the waves are out of phase and then when they get in phase the BIG waves SNEAK up on you! We have had high surf warnings here and so I am not surprised that the background microseismic activity is high right now.

My 24-hour heliplot shows this beat pattern quite clearly, check it out on my website at http://gbush.mcn.org/srn.gif ..


At 06:57 PM 10/21/2009, you wrote:

To all
Related to instrument quality- maybe. I have noticed a lot more microseismic activity the last few days. The background noise on my vertical is around +/- 300 counts @  8.7 sec  and 6.6 sec  (two narrow peaks). I don't remember this magnitude in years past. I'm sure it is weather related. I live about 200 miles east of the west coast of northern California. Anyone else noticed an increase in background lately? Every time I look at the output I think I'm looking at surface waves after an event.
Barry


George Bush
Sea Ranch, CA, USA
38.73775N, 123.48882W Subject: Re: microseisms From: Brett Nordgren brett3nt@............. Date: Thu, 22 Oct 2009 12:37:23 -0400 Larry, At 10:11 AM 10/22/2009 -0400, you wrote: >The other thing I would love to hear an explanation for is why the >microseism noise is so narrow band. When it is strong, it looks virtually >sinusoidal on the monitor, and an FFT of the data shows a very narrow >peak. Does anyone know why that is? This still appears to be an active subject among seismologists, but they seem to generally agree on the basics. Low frequency microseisms (generally 8-12 sec) are caused from pressure variations on the ocean floor from large ocean swells. These then get transmitted over great distances through the crust as surface waves. In the Northern hemisphere there are two places where these effects appear mostly to originate, one in the Northeastern Pacific off the Alaska and Canada coasts, and one in the Atlantic, between Newfoundland and Greenland. It sounds to me like those two regions are somehow acting as "resonators" for the ocean wave energy generated by large ocean storms. Since ocean swells are sort of sinusoidal, often with a single predominant frequency, I'm not surprised that their microseisms would be too, and then like other surface waves, as they travel through the crust, any higher frequency harmonics will disappear. One popular theory has it that the double frequency (4-8) second waves result from the interaction of the main swell with a rebounding swell, generated when it hits a coast. The resulting vibration will be at twice the frequency of the original and similarly, somewhat sinusoidal. Another thing to watch when looking at microseisms is where any Low Pass filtering is set. In order for a wave to be non-sinusoidal it must contain harmonic frequencies which could get removed by filtering too low. Regards, Brett Watch our wiggles http://bnordgren.org/seismo/gif_images.htm or watch some very very good wiggles http://aslwww.cr.usgs.gov/Seismic_Data/telemetry_data/ANMO_24hr.html __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Instrument quality - microseisms From: ChrisAtUpw@....... Date: Thu, 22 Oct 2009 19:32:59 EDT In a message dated 22/10/2009 15:12:02 GMT Daylight Time, lconklin@............ writes: The other thing I would love to hear an explanation for is why the microseism noise is so narrow band. When it is strong, it looks virtually sinusoidal on the monitor, and an FFT of the data shows a very narrow peak. Does anyone know why that is? Hi Larry, Check _http://oceanworld.tamu.edu/resources/ocng_textbook/chapter16/chapter16_01.htm_ (http://oceanworld.tamu.edu/resources/ocng_textbook/chapter16/chapter16_01.htm) and _http://oceanworld.tamu.edu/resources/ocng_textbook/chapter16/chapter16_04.htm_ (http://oceanworld.tamu.edu/resources/ocng_textbook/chapter16/chapter16_04.htm) Microseisms are generated by ocean waves, wave action on coasts, cold fronts, storms, hurricanes.... there are several possible causes, some more local than others. At lower wind velocities, you get a much wider range of ocean wave periods and low amplitudes - nearer 'noise'. As the wind velocity and the wave fetch increase, the period increases and the distribution becomes very much more peaked. It may take 1000 wavelengths to fully develop an ocean wave. The 'losenges' that you occasionally see are interference effects from two or more sources. The low amplitude microseisms may have periods of 5 to 7 seconds. At high amplitudes you may see waves of 10 to 12 seconds with well defined beats. One source on the east coast is likely to be in the Atlantic south of Greenland. There is a rough patch of sea with a long fetch about 1,500 km east of Labrador at the moment, with ~20 ft waves. _http://www.oceanweather.com/data/_ (http://www.oceanweather.com/data/) Regards, Chris Chapman

In a message dated 22/10/2009 15:12:02 GMT Daylight Time,=20 lconklin@............ writes:
The=20 other thing I would love to hear an explanation for is why the microseis= m=20 noise is so narrow band.  When it is strong, it looks virtually=20 sinusoidal on the monitor, and an FFT of the data shows a very narrow=20 peak.  Does anyone know why that is?
Hi Larry,
 
    Check http://oceanworld.tamu.edu/resources/ocng_textbook/chapter16/= chapter16_01.htm
    and http://oceanworld.tamu.edu/resources/ocng_textbook/chapter16/= chapter16_04.htm
 
    Microseisms are generated by ocean waves, wav= e=20 action on coasts, cold fronts, storms, hurricanes.... there are several po= ssible=20 causes, some more local than others. At lower wind velocities, you get=20 a much wider range of ocean wave periods and low amplitudes - nearer= =20 'noise'. As the wind velocity and the wave fetch increase, the period incr= eases=20 and the distribution becomes very much more peaked. It may take 1000 wavel= engths=20 to fully develop an ocean wave. The 'losenges' that you occasionally see= are=20 interference effects from two or more sources. The low amplitude microseis= ms may=20 have periods of 5 to 7 seconds. At high amplitudes you may see waves of 10= to 12=20 seconds with well defined beats. One source on the east coast is like= ly to=20 be in the Atlantic south of Greenland. There is a rough patch of sea with= a long=20 fetch about 1,500 km east of Labrador at the moment, with ~20 ft= =20 waves. http://www.oceanweather.com/dat= a/
 
    Regards,
 
    Chris Chapman
Subject: Re: Instument Quality From: "Randy Pratt" rpratt@............. Date: Fri, 23 Oct 2009 01:29:45 -0500 Chris, I apologize for misreading your tone and intent. It's an unfortunate = attribute of email that it loses personality. I agree that a school = purchasing an instrument for instruction should have a high quality but = I don't see that our schools are at that point or that caveman is = recommending this as a school solution. =20 Let me try to explain my sensitivity. My son's middle school dropped = earth science to meet state mandates for an increase in physical = education hours. We moved shortly after that to another state. Here I = became involved with the science fair and to my shock the largest middle = school in the region did not participate. When I inquired I found no = contract for extra work outside the classroom hours so no science = projects. One high school science teacher explained to me that there is = no time to fit any extra topics in order to meet federal and state = curriculum guidelines. The one teacher that did let me demonstrate a = seismograph left the area and her job was cut. A German exchange = student I am hosting is near the top of the English class and shows = better understanding than most others according to her teacher. She has = only been in the US since August so what does that tell you. Our = political mandates are dumbing down the best students. It really is = approved and budgeted science only and that leaves only individual = interest. An old magazine article from 1960 something about a smoked drum = seismograph stuck in my mind until I started to research in 1995 and = build my first. The Lehman article has been the basis for many on this = list but few of us are using pipe fittings on a board anymore. Maybe = something simple like the caveman web page will spark other individual = interest. How well it functions doesn't matter if thinking is set in = motion and the steps to reach something better follow. That's where = learning starts. Think about what percent of aeronautical engineers = started with paper airplanes looping into the ground and being refolded? = Randy
Chris,
 
I apologize for misreading your tone = and=20 intent.  It's an unfortunate attribute of email that it loses=20 personality.  I agree that a school purchasing an instrument for=20 instruction should have a high quality but I don't see that our=20 schools are at that point or that caveman is recommending this as a = school=20 solution. 
 
Let me try to explain my = sensitivity.  My=20 son's middle school dropped earth science to meet state mandates for an = increase=20 in physical education hours.  We moved shortly after that = to another=20 state.  Here I became involved with the science fair and to my = shock the=20 largest middle school in the region did not participate.  When I = inquired I=20 found no contract for extra work outside the classroom hours so no = science=20 projects.  One high school science teacher explained to me that there is no time to fit any extra = topics in=20 order to meet federal and state curriculum guidelines.  The one = teacher=20 that did let me demonstrate a seismograph left the area = and her job=20 was cut.  A German exchange student I am hosting is near the = top of=20 the English class and shows better understanding than most others = according to=20 her teacher.  She has only been in the US since August so = what=20 does that tell you.  Our political mandates are dumbing down the = best=20 students.  It really is = approved and=20 budgeted science only and that leaves only individual = interest.
 
An old magazine article from 1960 = something=20 about a smoked drum seismograph stuck in my mind until I started to = research in=20 1995 and build my first.  The Lehman article has been the basis for = many on=20 this list but few of us are using pipe fittings on a board = anymore.  Maybe=20 something simple like the caveman web page will spark other = individual=20 interest.  How well it functions doesn't matter = if thinking is=20 set in motion and the steps to reach something better=20 follow.  That's where learning starts.  Think about what = percent=20 of aeronautical engineers started with paper airplanes looping into the = ground=20 and being refolded? 
 
Randy
Subject: Re: Instument Quality From: "Geoffrey" gmvoeth@........... Date: Fri, 23 Oct 2009 01:08:43 -0700 I always thought some kind of etchasketch would make a good a graphic device since when your done you can erase the thing over and over again. But unless you photographed it or something you would loose the graph forever. ----- Original Message ----- From: "Randy Pratt" To: Sent: Thursday, October 22, 2009 11:29 PM Subject: Re: Instument Quality Chris, I apologize for misreading your tone and intent. It's an unfortunate attribute of email that it loses personality. I agree that a school purchasing an instrument for instruction should have a high quality but I don't see that our schools are at that point or that caveman is recommending this as a school solution. Let me try to explain my sensitivity. My son's middle school dropped earth science to meet state mandates for an increase in physical education hours. We moved shortly after that to another state. Here I became involved with the science fair and to my shock the largest middle school in the region did not participate. When I inquired I found no contract for extra work outside the classroom hours so no science projects. One high school science teacher explained to me that there is no time to fit any extra topics in order to meet federal and state curriculum guidelines. The one teacher that did let me demonstrate a seismograph left the area and her job was cut. A German exchange student I am hosting is near the top of the English class and shows better understanding than most others according to her teacher. She has only been in the US since August so what does that tell you. Our political mandates are dumbing down the best students. It really is approved and budgeted science only and that leaves only individual interest. An old magazine article from 1960 something about a smoked drum seismograph stuck in my mind until I started to research in 1995 and build my first. The Lehman article has been the basis for many on this list but few of us are using pipe fittings on a board anymore. Maybe something simple like the caveman web page will spark other individual interest. How well it functions doesn't matter if thinking is set in motion and the steps to reach something better follow. That's where learning starts. Think about what percent of aeronautical engineers started with paper airplanes looping into the ground and being refolded? Randy __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Instument Quality From: "tchannel" tchannel@............ Date: Fri, 23 Oct 2009 07:11:08 -0600 I have a follow up question, only somewhat related. When the sensor is = completed, one of the first questions a novice might ask is "What can I = expect to see"? I know this would depend, not only the sensor, but = many other things, like the location, and the other components of the = station. We all try to build the best one we can, using the ideas and materials = we have. This site is the best tool I have in my workshop. The most common statement I have seen is, "My sensor can see >7.0M = anywhere in the world" I have never complete a sensor which could not = do this. I view USGS sites, and find equipment costing thousands of dollars, pick = up more and small events, then mine, but not not by much. I also know, several of my ideas are not as sensitive as they could be, = and some of the ideas simply don't work. I learn a lot from both = failures and successes. Could someone state, as best as you can "What should I expect to see"? Something like: >6.8m anywhere in the world. >6.m within 90 degrees >5.m within 30 degrees =20 All who have been doing this for a while, know what our equipment will = see. If someone, with really nice homebuilt sensors, would share these = numbers, it would act, for me, as a benchmark. Thanks, Ted ----- Original Message -----=20 From: Randy Pratt=20 To: psn-l@................. Sent: Friday, October 23, 2009 12:29 AM Subject: Re: Instument Quality Chris, I apologize for misreading your tone and intent. It's an unfortunate = attribute of email that it loses personality. I agree that a school = purchasing an instrument for instruction should have a high quality but = I don't see that our schools are at that point or that caveman is = recommending this as a school solution. =20 Let me try to explain my sensitivity. My son's middle school dropped = earth science to meet state mandates for an increase in physical = education hours. We moved shortly after that to another state. Here I = became involved with the science fair and to my shock the largest middle = school in the region did not participate. When I inquired I found no = contract for extra work outside the classroom hours so no science = projects. One high school science teacher explained to me that there is = no time to fit any extra topics in order to meet federal and state = curriculum guidelines. The one teacher that did let me demonstrate a = seismograph left the area and her job was cut. A German exchange = student I am hosting is near the top of the English class and shows = better understanding than most others according to her teacher. She has = only been in the US since August so what does that tell you. Our = political mandates are dumbing down the best students. It really is = approved and budgeted science only and that leaves only individual = interest. An old magazine article from 1960 something about a smoked drum = seismograph stuck in my mind until I started to research in 1995 and = build my first. The Lehman article has been the basis for many on this = list but few of us are using pipe fittings on a board anymore. Maybe = something simple like the caveman web page will spark other individual = interest. How well it functions doesn't matter if thinking is set in = motion and the steps to reach something better follow. That's where = learning starts. Think about what percent of aeronautical engineers = started with paper airplanes looping into the ground and being refolded? = Randy
I have a follow up question, only = somewhat=20 related.   When the sensor is completed, one of the first = questions a=20 novice might ask is "What can I expect to see"?     = I know=20 this would depend, not only the sensor, but many other things, like the=20 location, and the other components of the station.
We all try to build the best one we = can, using the=20 ideas and materials we have.   This site is the best tool I = have in my=20 workshop.
 
The most common statement I have seen = is,  "My=20 sensor can see >7.0M anywhere in the world"   I have never = complete=20 a sensor which could not do this.
I view USGS sites, and find equipment = costing=20 thousands of dollars, pick up more and small events, then mine, but not = not by=20 much.
I also know, several of my ideas are = not as=20 sensitive as they could be, and some of the ideas simply don't = work.  =20 I learn a lot from both failures and successes.
 
Could someone state, as best as you can = "What=20 should I expect to see"?
Something like:
>6.8m anywhere in the = world.
>6.m within 90 degrees
>5.m within 30 degrees   =
 
All who have been doing this for a = while, know what=20 our equipment will see.   If someone, with really nice = homebuilt=20 sensors, would share these numbers, it would act, for me, as a=20 benchmark.
 
Thanks, Ted
----- Original Message -----
From:=20 Randy=20 Pratt
Sent: Friday, October 23, 2009 = 12:29=20 AM
Subject: Re: Instument = Quality

Chris,
 
I apologize for misreading your tone = and=20 intent.  It's an unfortunate attribute of email that it = loses=20 personality.  I agree that a school purchasing an instrument for=20 instruction should have a high quality but I don't see that our=20 schools are at that point or that caveman is recommending this as = a=20 school solution. 
 
Let me try to explain my = sensitivity.  My=20 son's middle school dropped earth science to meet state mandates for = an=20 increase in physical education hours.  We moved shortly after = that=20 to another state.  Here I became involved with the science = fair and=20 to my shock the largest middle school in the region did not = participate. =20 When I inquired I found no contract for extra work outside the = classroom hours=20 so no science projects.  One high school science teacher=20 explained to me that there is = no time to=20 fit any extra topics in order to meet federal and state curriculum=20 guidelines.  The one teacher that did let me demonstrate a=20 seismograph left the area and her job was cut.  = A German=20 exchange student I am hosting is near the top of the English class and = shows=20 better understanding than most others according to her teacher.  = She has=20 only been in the US since August so what does that tell = you. =20 Our political mandates are dumbing down the best=20 students.  It really is = approved and=20 budgeted science only and that leaves only individual = interest.
 
An old magazine article from = 1960 something=20 about a smoked drum seismograph stuck in my mind until I started to = research=20 in 1995 and build my first.  The Lehman article has been the = basis for=20 many on this list but few of us are using pipe fittings on a board=20 anymore.  Maybe something simple like the caveman web page = will=20 spark other individual interest.  How well it functions doesn't = matter=20 if thinking is set in motion and the steps to = reach something=20 better follow.  That's where learning starts.  Think = about what=20 percent of aeronautical engineers started with paper airplanes looping = into=20 the ground and being refolded? 
 
Randy
Subject: Re: Instument Quality From: Larry Conklin lconklin@............ Date: Fri, 23 Oct 2009 09:52:21 -0400 Hi Ted, I have an Excel spreadsheet that I use to record the events I've seen with my SG system. The sheet includes a magnitude vs distance scatter plot, with each point color coded (A - D) to represent my (very) subjective assessment of the quality of the detection. I have a database of over 800 events. My system is far from an optimal construction and my location is pretty noisy, but I think overall my results are reasonably typical of a fair to middlen amateur system. If you or anyone else would like a copy of the sheet and data to examine for comparison to your own results, I'd be happy to send it to you. I've included a few other features, and I use it to manage all of my event files. Larry tchannel wrote: > I have a follow up question, only somewhat related. When the sensor is > completed, one of the first questions a novice might ask is "What can I > expect to see"? I know this would depend, not only the sensor, but > many other things, like the location, and the other components of the > station. > We all try to build the best one we can, using the ideas and materials > we have. This site is the best tool I have in my workshop. > > The most common statement I have seen is, "My sensor can see >7.0M > anywhere in the world" I have never complete a sensor which could not > do this. > I view USGS sites, and find equipment costing thousands of dollars, pick > up more and small events, then mine, but not not by much. > I also know, several of my ideas are not as sensitive as they could be, > and some of the ideas simply don't work. I learn a lot from both > failures and successes. > > Could someone state, as best as you can "What should I expect to see"? > Something like: > >6.8m anywhere in the world. > >6.m within 90 degrees > >5.m within 30 degrees > > All who have been doing this for a while, know what our equipment will > see. If someone, with really nice homebuilt sensors, would share these > numbers, it would act, for me, as a benchmark. > > Thanks, Ted > > ----- Original Message ----- > *From:* Randy Pratt > *To:* psn-l@.............. > *Sent:* Friday, October 23, 2009 12:29 AM > *Subject:* Re: Instument Quality > > Chris, > > I apologize for misreading your tone and intent. It's an > unfortunate attribute of email that it loses personality. I agree > that a school purchasing an instrument for instruction should have a > high quality but I don't see that our schools are at that point or > that caveman is recommending this as a school solution. > > Let me try to explain my sensitivity. My son's middle school > dropped earth science to meet state mandates for an increase in > physical education hours. We moved shortly after that to another > state. Here I became involved with the science fair and to my shock > the largest middle school in the region did not participate. When I > inquired I found no contract for extra work outside the classroom > hours so no science projects. One high school science teacher > explained to me that there is no time to fit any extra topics in > order to meet federal and state curriculum guidelines. The one > teacher that did let me demonstrate a seismograph left the area > and her job was cut. A German exchange student I am hosting is near > the top of the English class and shows better understanding than > most others according to her teacher. She has only been in the > US since August so what does that tell you. Our political mandates > are dumbing down the best students. It really is approved and > budgeted science only and that leaves only individual interest. > > An old magazine article from 1960 something about a smoked drum > seismograph stuck in my mind until I started to research in 1995 and > build my first. The Lehman article has been the basis for many on > this list but few of us are using pipe fittings on a board anymore. > Maybe something simple like the caveman web page will spark other > individual interest. How well it functions doesn't matter > if thinking is set in motion and the steps to reach something better > follow. That's where learning starts. Think about what percent of > aeronautical engineers started with paper airplanes looping into the > ground and being refolded? > > Randy __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Instument Quality From: "tchannel" tchannel@............ Date: Fri, 23 Oct 2009 08:07:41 -0600 Yes Please, Larry, I would like your spreadsheet. tchannel@............ Ted ----- Original Message ----- From: "Larry Conklin" To: Sent: Friday, October 23, 2009 7:52 AM Subject: Re: Instument Quality > Hi Ted, > > I have an Excel spreadsheet that I use to record the events I've seen with > my SG system. The sheet includes a magnitude vs distance scatter plot, > with each point color coded (A - D) to represent my (very) subjective > assessment of the quality of the detection. I have a database of over 800 > events. > > My system is far from an optimal construction and my location is pretty > noisy, but I think overall my results are reasonably typical of a fair to > middlen amateur system. > > If you or anyone else would like a copy of the sheet and data to examine > for comparison to your own results, I'd be happy to send it to you. I've > included a few other features, and I use it to manage all of my event > files. > > Larry > > tchannel wrote: >> I have a follow up question, only somewhat related. When the sensor is >> completed, one of the first questions a novice might ask is "What can I >> expect to see"? I know this would depend, not only the sensor, but >> many other things, like the location, and the other components of the >> station. >> We all try to build the best one we can, using the ideas and materials we >> have. This site is the best tool I have in my workshop. >> The most common statement I have seen is, "My sensor can see >7.0M >> anywhere in the world" I have never complete a sensor which could not >> do this. >> I view USGS sites, and find equipment costing thousands of dollars, pick >> up more and small events, then mine, but not not by much. >> I also know, several of my ideas are not as sensitive as they could be, >> and some of the ideas simply don't work. I learn a lot from both >> failures and successes. >> Could someone state, as best as you can "What should I expect to see"? >> Something like: >> >6.8m anywhere in the world. >> >6.m within 90 degrees >> >5.m within 30 degrees All who have been doing this for a while, know >> what our equipment will see. If someone, with really nice homebuilt >> sensors, would share these numbers, it would act, for me, as a benchmark. >> Thanks, Ted >> >> ----- Original Message ----- >> *From:* Randy Pratt >> *To:* psn-l@.............. >> *Sent:* Friday, October 23, 2009 12:29 AM >> *Subject:* Re: Instument Quality >> >> Chris, >> I apologize for misreading your tone and intent. It's an >> unfortunate attribute of email that it loses personality. I agree >> that a school purchasing an instrument for instruction should have a >> high quality but I don't see that our schools are at that point or >> that caveman is recommending this as a school solution. Let me try to >> explain my sensitivity. My son's middle school >> dropped earth science to meet state mandates for an increase in >> physical education hours. We moved shortly after that to another >> state. Here I became involved with the science fair and to my shock >> the largest middle school in the region did not participate. When I >> inquired I found no contract for extra work outside the classroom >> hours so no science projects. One high school science teacher >> explained to me that there is no time to fit any extra topics in >> order to meet federal and state curriculum guidelines. The one >> teacher that did let me demonstrate a seismograph left the area >> and her job was cut. A German exchange student I am hosting is near >> the top of the English class and shows better understanding than >> most others according to her teacher. She has only been in the >> US since August so what does that tell you. Our political mandates >> are dumbing down the best students. It really is approved and >> budgeted science only and that leaves only individual interest. >> An old magazine article from 1960 something about a smoked drum >> seismograph stuck in my mind until I started to research in 1995 and >> build my first. The Lehman article has been the basis for many on >> this list but few of us are using pipe fittings on a board anymore. >> Maybe something simple like the caveman web page will spark other >> individual interest. How well it functions doesn't matter >> if thinking is set in motion and the steps to reach something better >> follow. That's where learning starts. Think about what percent of >> aeronautical engineers started with paper airplanes looping into the >> ground and being refolded? Randy > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with the body of the > message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: ELECTRON MICROSCOPE From: "Geoffrey" gmvoeth@........... Date: Fri, 23 Oct 2009 07:23:42 -0700 Would it be possible to somehow use an electron microscope to actually measure a real displacement of a pendulum or spring mass thingamajig ?? __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Instument Quality From: AHrubetz@....... Date: Fri, 23 Oct 2009 10:21:56 EDT Hi Larry, Would appreciate receiving a copy. Thanks and regards, Al In a message dated 10/23/2009 8:53:13 A.M. Central Daylight Time, lconklin@............ writes: Hi Ted, I have an Excel spreadsheet that I use to record the events I've seen with my SG system. The sheet includes a magnitude vs distance scatter plot, with each point color coded (A - D) to represent my (very) subjective assessment of the quality of the detection. I have a database of over 800 events. My system is far from an optimal construction and my location is pretty noisy, but I think overall my results are reasonably typical of a fair to middlen amateur system. If you or anyone else would like a copy of the sheet and data to examine for comparison to your own results, I'd be happy to send it to you. I've included a few other features, and I use it to manage all of my event files. Larry tchannel wrote: > I have a follow up question, only somewhat related. When the sensor is > completed, one of the first questions a novice might ask is "What can I > expect to see"? I know this would depend, not only the sensor, but > many other things, like the location, and the other components of the > station. > We all try to build the best one we can, using the ideas and materials > we have. This site is the best tool I have in my workshop. > > The most common statement I have seen is, "My sensor can see >7.0M > anywhere in the world" I have never complete a sensor which could not > do this. > I view USGS sites, and find equipment costing thousands of dollars, pick > up more and small events, then mine, but not not by much. > I also know, several of my ideas are not as sensitive as they could be, > and some of the ideas simply don't work. I learn a lot from both > failures and successes. > > Could someone state, as best as you can "What should I expect to see"? > Something like: > >6.8m anywhere in the world. > >6.m within 90 degrees > >5.m within 30 degrees > > All who have been doing this for a while, know what our equipment will > see. If someone, with really nice homebuilt sensors, would share these > numbers, it would act, for me, as a benchmark. > > Thanks, Ted > > ----- Original Message ----- > *From:* Randy Pratt > *To:* psn-l@.............. > *Sent:* Friday, October 23, 2009 12:29 AM > *Subject:* Re: Instument Quality > > Chris, > > I apologize for misreading your tone and intent. It's an > unfortunate attribute of email that it loses personality. I agree > that a school purchasing an instrument for instruction should have a > high quality but I don't see that our schools are at that point or > that caveman is recommending this as a school solution. > > Let me try to explain my sensitivity. My son's middle school > dropped earth science to meet state mandates for an increase in > physical education hours. We moved shortly after that to another > state. Here I became involved with the science fair and to my shock > the largest middle school in the region did not participate. When I > inquired I found no contract for extra work outside the classroom > hours so no science projects. One high school science teacher > explained to me that there is no time to fit any extra topics in > order to meet federal and state curriculum guidelines. The one > teacher that did let me demonstrate a seismograph left the area > and her job was cut. A German exchange student I am hosting is near > the top of the English class and shows better understanding than > most others according to her teacher. She has only been in the > US since August so what does that tell you. Our political mandates > are dumbing down the best students. It really is approved and > budgeted science only and that leaves only individual interest. > > An old magazine article from 1960 something about a smoked drum > seismograph stuck in my mind until I started to research in 1995 and > build my first. The Lehman article has been the basis for many on > this list but few of us are using pipe fittings on a board anymore. > Maybe something simple like the caveman web page will spark other > individual interest. How well it functions doesn't matter > if thinking is set in motion and the steps to reach something better > follow. That's where learning starts. Think about what percent of > aeronautical engineers started with paper airplanes looping into the > ground and being refolded? > > Randy __________________________________________________________ Public Seismic Network Mailing List (PSN-L) To leave this list email PSN-L-REQUEST@.............. with the body of the message (first line only): unsubscribe See http://www.seismicnet.com/maillist.html for more information.
Hi Larry,
    Would appreciate recei= ving a=20 copy.
    Thanks and=20 regards,
    Al
 
In a message dated 10/23/2009 8:53:13 A.M. Central Daylight Time,=20 lconklin@............ writes:
Hi=20 Ted,

I have an Excel spreadsheet that I use to record the events= I've=20 seen
with my SG system.  The sheet includes a magnitude vs dist= ance=20 scatter
plot, with each point color coded (A - D) to represent my (v= ery)=20
subjective assessment of the quality of the detection.  I have= a=20
database of over 800 events.

My system is far from an optimal= =20 construction and my location is pretty
noisy, but I think overall my= =20 results are reasonably typical of a fair
to middlen amateur=20 system.

If you or anyone else would like a copy of the sheet and= data=20 to examine
for comparison to your own results, I'd be happy to send= it to=20 you.
I've included a few other features, and I use it to manage all= of my=20
event files.

Larry

tchannel wrote:
> I have a fo= llow=20 up question, only somewhat related.   When the sensor is
&= gt;=20 completed, one of the first questions a novice might ask is "What can I= =20
> expect to see"?     I know this would depend, no= t only=20 the sensor, but
> many other things, like the location, and the= other=20 components of the
> station.
> We all try to build the best= one=20 we can, using the ideas and materials
> we have.   This= site=20 is the best tool I have in my workshop.
> 
> The most= common=20 statement I have seen is,  "My sensor can see >7.0M
> any= where=20 in the world"   I have never complete a sensor which could not= =20
> do this.
> I view USGS sites, and find equipment costing= =20 thousands of dollars, pick
> up more and small events, then mine,= but=20 not not by much.
> I also know, several of my ideas are not as sen= sitive=20 as they could be,
> and some of the ideas simply don't=20 work.   I learn a lot from both
> failures and=20 successes.
> 
> Could someone state, as best as you ca= n=20 "What should I expect to see"?
> Something like:
>  >= ;6.8m=20 anywhere in the world.
>  >6.m within 90 degrees
>&n= bsp;=20 >5.m within 30 degrees 
> 
> All who have bee= n=20 doing this for a while, know what our equipment will
> see. =  =20 If someone, with really nice homebuilt sensors, would share these
&g= t;=20 numbers, it would act, for me, as a benchmark.
> 
> Th= anks,=20 Ted
>
>     ----- Original Message=20 -----
>     *From:* Randy Pratt=20 <mailto:rpratt@.............>
>     *To:*=20 psn-l@.............. <mailto:psn-l@..............>
> = =20    *Sent:* Friday, October 23, 2009 12:29 AM
> =20    *Subject:* Re: Instument Quality
>
> =20    Chris,
>     
>   &nb= sp; I=20 apologize for misreading your tone and intent.  It's an
>&nbs= p;=20    unfortunate attribute of email that it loses personality.&n= bsp; I=20 agree
>     that a school purchasing an instrument= for=20 instruction should have a
>     high quality but I= don't=20 see that our schools are at that point or
>     tha= t=20 caveman is recommending this as a school solution.
>   = =20  
>     Let me try to explain my sensitivity.=  =20 My son's middle school
>     dropped earth science= to=20 meet state mandates for an increase in
>     physic= al=20 education hours.  We moved shortly after that to another
>&nb= sp;=20    state.  Here I became involved with the science fair= and to=20 my shock
>     the largest middle school in the reg= ion=20 did not participate.  When I
>     inquired I= found=20 no contract for extra work outside the classroom
>   &nb= sp;=20 hours so no science projects.  One high school science=20 teacher
>     explained to me that there is no time= to=20 fit any extra topics in
>     order to meet federal= and=20 state curriculum guidelines.  The one
>     te= acher=20 that did let me demonstrate a seismograph left the area
> =20    and her job was cut.  A German exchange student I am= hosting=20 is near
>     the top of the English class and show= s=20 better understanding than
>     most others accordi= ng to=20 her teacher.  She has only been in the
>    = US=20 since August so what does that tell you.  Our political=20 mandates
>     are dumbing down the best students.&= nbsp;=20 It really is approved and
>     budgeted science on= ly and=20 that leaves only individual interest.
>     =20
>     An old magazine article from 1960 something= about=20 a smoked drum
>     seismograph stuck in my mind un= til I=20 started to research in 1995 and
>     build my=20 first.  The Lehman article has been the basis for many on
>&n= bsp;=20    this list but few of us are using pipe fittings on a board= =20 anymore.
>     Maybe something simple like the cav= eman=20 web page will spark other
>     individual=20 interest.  How well it functions doesn't matter
> =20    if thinking is set in motion and the steps to reach somethi= ng=20 better
>     follow.  That's where learning=20 starts.  Think about what percent of
>    =20 aeronautical engineers started with paper airplanes looping into=20 the
>     ground and being refolded?
> = =20    
>    =20 Randy
__________________________________________________________
<= BR>Public=20 Seismic Network Mailing List (PSN-L)

To leave this list email=20 PSN-L-REQUEST@.............. with
the body of the message (first lin= e=20 only): unsubscribe
See http://www.seismicnet.com/maillist.html for mo= re=20 information.
Subject: Re: Instument Quality From: "tchannel" tchannel@............ Date: Fri, 23 Oct 2009 08:28:18 -0600 I forgot to mention another variables, obvious, but may be not to newcomers. Each earthquake is unique. Sometimes a 6m will be clearly visible, and sometimes another 6m, same distance, same size will not be visible. And of course your background noise at the time, is a major factor. Lastly, the preliminary USGS event reports, can be modified, as more information becomes available, changing a 6.0m to a 5.7m etc. Ted ----- Original Message ----- From: "Larry Conklin" To: Sent: Friday, October 23, 2009 7:52 AM Subject: Re: Instument Quality > Hi Ted, > > I have an Excel spreadsheet that I use to record the events I've seen with > my SG system. The sheet includes a magnitude vs distance scatter plot, > with each point color coded (A - D) to represent my (very) subjective > assessment of the quality of the detection. I have a database of over 800 > events. > > My system is far from an optimal construction and my location is pretty > noisy, but I think overall my results are reasonably typical of a fair to > middlen amateur system. > > If you or anyone else would like a copy of the sheet and data to examine > for comparison to your own results, I'd be happy to send it to you. I've > included a few other features, and I use it to manage all of my event > files. > > Larry > > tchannel wrote: >> I have a follow up question, only somewhat related. When the sensor is >> completed, one of the first questions a novice might ask is "What can I >> expect to see"? I know this would depend, not only the sensor, but >> many other things, like the location, and the other components of the >> station. >> We all try to build the best one we can, using the ideas and materials we >> have. This site is the best tool I have in my workshop. >> The most common statement I have seen is, "My sensor can see >7.0M >> anywhere in the world" I have never complete a sensor which could not >> do this. >> I view USGS sites, and find equipment costing thousands of dollars, pick >> up more and small events, then mine, but not not by much. >> I also know, several of my ideas are not as sensitive as they could be, >> and some of the ideas simply don't work. I learn a lot from both >> failures and successes. >> Could someone state, as best as you can "What should I expect to see"? >> Something like: >> >6.8m anywhere in the world. >> >6.m within 90 degrees >> >5.m within 30 degrees All who have been doing this for a while, know >> what our equipment will see. If someone, with really nice homebuilt >> sensors, would share these numbers, it would act, for me, as a benchmark. >> Thanks, Ted >> >> ----- Original Message ----- >> *From:* Randy Pratt >> *To:* psn-l@.............. >> *Sent:* Friday, October 23, 2009 12:29 AM >> *Subject:* Re: Instument Quality >> >> Chris, >> I apologize for misreading your tone and intent. It's an >> unfortunate attribute of email that it loses personality. I agree >> that a school purchasing an instrument for instruction should have a >> high quality but I don't see that our schools are at that point or >> that caveman is recommending this as a school solution. Let me try to >> explain my sensitivity. My son's middle school >> dropped earth science to meet state mandates for an increase in >> physical education hours. We moved shortly after that to another >> state. Here I became involved with the science fair and to my shock >> the largest middle school in the region did not participate. When I >> inquired I found no contract for extra work outside the classroom >> hours so no science projects. One high school science teacher >> explained to me that there is no time to fit any extra topics in >> order to meet federal and state curriculum guidelines. The one >> teacher that did let me demonstrate a seismograph left the area >> and her job was cut. A German exchange student I am hosting is near >> the top of the English class and shows better understanding than >> most others according to her teacher. She has only been in the >> US since August so what does that tell you. Our political mandates >> are dumbing down the best students. It really is approved and >> budgeted science only and that leaves only individual interest. >> An old magazine article from 1960 something about a smoked drum >> seismograph stuck in my mind until I started to research in 1995 and >> build my first. The Lehman article has been the basis for many on >> this list but few of us are using pipe fittings on a board anymore. >> Maybe something simple like the caveman web page will spark other >> individual interest. How well it functions doesn't matter >> if thinking is set in motion and the steps to reach something better >> follow. That's where learning starts. Think about what percent of >> aeronautical engineers started with paper airplanes looping into the >> ground and being refolded? Randy > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with the body of the > message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: ELECTRON MICROSCOPE From: ChrisAtUpw@....... Date: Fri, 23 Oct 2009 11:12:34 EDT In a message dated 23/10/2009, gmvoeth@........... writes: Would it be possible to somehow use an electron microscope to actually measure a real displacement of a pendulum or spring mass thingamajig ?? Hi Goeff, I suppose that you could build one inside a vacuum system, but why bother? LVDT sensors can be made to work down to 0.1 nano metre. Differential capacitor types can give over 10x more resolution and you are then close to atomic dimensions. The practical problem then becomes the temperature stability of the sensor. However, this is way below the amplitude of the quiet earth graph - you can't see any signals below the natural seismic noise level. Modern seismometers are usually enclosed in a sealed can to remove atmospheric pressure noise. Regards, Chris Chapman
In a message dated 23/10/2009, gmvoeth@........... writes:
Would it=20 be possible to somehow use an electron microscope to actually measure a= =20 real
displacement of a pendulum or spring mass thingamajig=20 ??
Hi Goeff,
 
        I suppose that you co= uld=20 build one inside a vacuum system, but why bother?
 
    LVDT sensors can be made to work down to 0.1= nano=20 metre. Differential capacitor types can give over 10x more resolution and= you=20 are then close to atomic dimensions. The practical problem then becom= es the=20 temperature stability of the sensor.
    
    However, this is way below the amplitude of= the=20 quiet earth graph - you can't see any signals below the natural seism= ic=20 noise level. Modern seismometers are usually enclosed in a sealed can to= remove=20 atmospheric pressure noise.
 
    Regards,
 
    Chris Chapman
Subject: Re: Instument Quality From: Brett Nordgren brett3nt@............. Date: Fri, 23 Oct 2009 11:18:09 -0400 Ted, At 07:11 AM 10/23/2009 -0600, you wrote: >I have a follow up question, only somewhat related. When the sensor is >completed, one of the first questions a novice might ask is "What can I >expect to see"? I know this would depend, not only the sensor, but >many other things, like the location, and the other components of the station. I agree that it depends on a lot of things other than the sensor quality. For the smaller quakes, the fault orientation and depth are also important. Some that are "pointed" properly and not too deep can come in strongly, while others of the same magnitude and distance will not be visible. Using the worldwide statistics from http://neic.usgs.gov/neis/eqlists/eqstats.html I get, roughly: M 8+ 1/ year M 7+ 1/ 3 weeks M 6+ 3/ week M 5+ 4/ day M 4+ 1.7/ hour As noted, the rate for the lower magnitudes should be reduced to eliminate quakes which are not oriented well or too deep to generate surface waves, and depending on where I am located, adjusted to favor those quakes which are closer. I have the impression that fault orientation may be considerably more important than distance. If my instrument and site allow me to see Mag 7's, I may be waiting weeks to see something. If it can see half of all the Mag. 5's, I will probably be seeing a couple a day. That would be my strongest argument for working to have the best setup possible--lots more action. Dave (California) Nelson's vertical will see the surface waves from a few in the high 4's and many in the 5's. See the link below: Curiously, the ANMO Albuquerque borehole seismo, considered to be among the best, sometimes doesn't see as much as the home-built instrument. They apparently are using a 20-second *low pass* filter for their helicorder trace, which often cuts out quite a lot which would otherwise be seen with less agressive filtering. Brett Watch our wiggles http://bnordgren.org/seismo/gif_images.htm or watch some very very good wiggles http://aslwww.cr.usgs.gov/Seismic_Data/telemetry_data/ANMO_24hr.html __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Instument Quality From: Barry Lotz barry_lotz@............. Date: Fri, 23 Oct 2009 19:01:42 -0700 (PDT) Larry I like the idea. I have been using a spiral binder and pencil for 17 yrs. := ). I have used Excel for other things but -- sometimes it's hard to see the= obvious. I would like to include the event info and distance to my station= and also the signal size I record (P-P). That way I can plot count vs magn= itude vs distance with the computer rather than by hand. Is there a conveni= ent way to import the=A0 winquake data? I can always do it by hand. Regards Barry =A0 --- On Fri, 10/23/09, Larry Conklin wrote: From: Larry Conklin Subject: Re: Instument Quality To: psn-l@.............. Date: Friday, October 23, 2009, 6:52 AM Hi Ted, I have an Excel spreadsheet that I use to record the events I've seen with = my SG system.=A0 The sheet includes a magnitude vs distance scatter plot, w= ith each point color coded (A - D) to represent my (very) subjective assess= ment of the quality of the detection.=A0 I have a database of over 800 even= ts. My system is far from an optimal construction and my location is pretty noi= sy, but I think overall my results are reasonably typical of a fair to midd= len amateur system. If you or anyone else would like a copy of the sheet and data to examine fo= r comparison to your own results, I'd be happy to send it to you. I've incl= uded a few other features, and I use it to manage all of my event files. Larry tchannel wrote: > I have a follow up question, only somewhat related.=A0=A0=A0When the sens= or is completed, one of the first questions a novice might ask is "What can= I expect to see"?=A0 =A0=A0=A0I know this would depend, not only the senso= r, but many other things, like the location, and the other components of th= e station. > We all try to build the best one we can, using the ideas and materials we= have.=A0=A0=A0This site is the best tool I have in my workshop. >=A0 The most common statement I have seen is,=A0 "My sensor can see >7.0M = anywhere in the world"=A0=A0=A0I have never complete a sensor which could n= ot do this. > I view USGS sites, and find equipment costing thousands of dollars, pick = up more and small events, then mine, but not not by much. > I also know, several of my ideas are not as sensitive as they could be, a= nd some of the ideas simply don't work.=A0=A0=A0I learn a lot from both fai= lures and successes. >=A0 Could someone state, as best as you can "What should I expect to see"? > Something like: >=A0 >6.8m anywhere in the world. >=A0 >6.m within 90 degrees >=A0 >5.m within 30 degrees=A0=A0=A0All who have been doing this for a whil= e, know what our equipment will see.=A0=A0=A0If someone, with really nice h= omebuilt sensors, would share these numbers, it would act, for me, as a ben= chmark. >=A0 Thanks, Ted >=20 >=A0 =A0=A0=A0----- Original Message ----- >=A0 =A0=A0=A0*From:* Randy Pratt >=A0 =A0=A0=A0*To:* psn-l@.............. >=A0 =A0=A0=A0*Sent:* Friday, October 23, 2009 12:29 AM >=A0 =A0=A0=A0*Subject:* Re: Instument Quality >=20 >=A0 =A0=A0=A0Chris, >=A0 =A0 =A0 =A0 =A0 I apologize for misreading your tone and intent.=A0 It= 's an >=A0 =A0=A0=A0unfortunate attribute of email that it loses personality.=A0 = I agree >=A0 =A0=A0=A0that a school purchasing an instrument for instruction should= have a >=A0 =A0=A0=A0high quality but I don't see that our schools are at that poi= nt or >=A0 =A0=A0=A0that caveman is recommending this as a school solution.=A0 = =A0 =A0 =A0 =A0 Let me try to explain my sensitivity.=A0 My son's middle sc= hool >=A0 =A0=A0=A0dropped earth science to meet state mandates for an increase = in >=A0 =A0=A0=A0physical education hours.=A0 We moved shortly after that to a= nother >=A0 =A0=A0=A0state.=A0 Here I became involved with the science fair and to= my shock >=A0 =A0=A0=A0the largest middle school in the region did not participate.= =A0 When I >=A0 =A0=A0=A0inquired I found no contract for extra work outside the class= room >=A0 =A0=A0=A0hours so no science projects.=A0 One high school science teac= her >=A0 =A0=A0=A0explained to me that there is no time to fit any extra topics= in >=A0 =A0=A0=A0order to meet federal and state curriculum guidelines.=A0 The= one >=A0 =A0=A0=A0teacher that did let me demonstrate a seismograph left the ar= ea >=A0 =A0=A0=A0and her job was cut.=A0 A German exchange student I am hostin= g is near >=A0 =A0=A0=A0the top of the English class and shows better understanding t= han >=A0 =A0=A0=A0most others according to her teacher.=A0 She has only been in= the >=A0 =A0=A0=A0US since August so what does that tell you.=A0 Our political = mandates >=A0 =A0=A0=A0are dumbing down the best students.=A0 It really is approved = and >=A0 =A0=A0=A0budgeted science only and that leaves only individual interes= t. >=A0 =A0 =A0 =A0 =A0 An old magazine article from 1960 something about a sm= oked drum >=A0 =A0=A0=A0seismograph stuck in my mind until I started to research in 1= 995 and >=A0 =A0=A0=A0build my first.=A0 The Lehman article has been the basis for = many on >=A0 =A0=A0=A0this list but few of us are using pipe fittings on a board an= ymore.=A0 =A0=A0=A0Maybe something simple like the caveman web page will sp= ark other >=A0 =A0=A0=A0individual interest.=A0 How well it functions doesn't matter >=A0 =A0=A0=A0if thinking is set in motion and the steps to reach something= better >=A0 =A0=A0=A0follow.=A0 That's where learning starts.=A0 Think about what = percent of >=A0 =A0=A0=A0aeronautical engineers started with paper airplanes looping i= nto the >=A0 =A0=A0=A0ground and being refolded?=A0 =A0 =A0 =A0 =A0 Randy __________________________________________________________ Public Seismic Network Mailing List (PSN-L)
Stephen
Thanks very much - also.
Barry<= br>

--- On Wed, 10/21/09, Stephen & Kathy <skmort@wildb= lue.net> wrote:

From: Stephen &a= mp; Kathy <skmort@............>
Subject: Re: Instrument quality - = microseisms
To: psn-l@..............
Date: Wednesday, October 21, 200= 9, 8:53 PM

=0A=0A=0A =0A = =0AHi Barry, I'm a little south of you...  = I also=0Ahave increased noise.  Whenever I see this kind of noise, I = check with=0ABerkeley at:
=0Ahttp://quake.geo.berkeley.edu/bdsn/make_seismogram.html
=0A
=0AIf you just create plot without setting time, it will create= todays=0Aseismogram for CMB... I use 4 for compression to get an hour per = line; =0Aand pixels at 25 to get a little separation.  Sorry if I= am sharing old=0Ainfo...   if so, maybe it will help others? =0A
=0AIf you check the following ocean weather link you will see why..= .. =0Athere are 20 to 25 foot waves off the NW USA coast.   E= arlier, they=0Awere showing up to 30 foot waves. You can click on any box t= o see the=0Aconditions in the box...  I click on the box that shows Al= aska to below=0ABaja...   and yes, the energy is apparently comin= g from 200 to 400=0Amiles away:
=0Ahttp://www.oceanweather.com/data/
=0A
=0AAt one time I had my ga= in so high that noise like this would set off my=0Aalarm, (I have a separat= e alarm, which I built before I had a computer=0Aand recording capability).=
=0A  Stephen
=0A  PSN Station #55
=0A  38.828N&nbs= p; 120.979W
=0A  near Pilot Hill Calif  
=0A=0ABarry Lotz wrote:=0A
=0A =0A =0A =0A = =0A =0A <= /tbody>=0A

=0ATo all=0ARelated to instrument quality- maybe. I have noticed a lot more=0Amicro= seismic activity the last few days. The background noise on my=0Avertical i= s around +/- 300 counts @  8.7 sec  and 6.6 sec  (two narrow= =0Apeaks). I don't remember this magnitude in years past. I'm sure it is=0A= weather related. I live about 200 miles east of the west coast of=0Anorther= n California. Anyone else noticed an increase in background=0Alately? Every= time I look at the output I think I'm looking at surface=0Awaves after an = event.
=0ABarry
=0A
=0A
=0A
=0A =0A
Larry
I like the idea. I have been using a= spiral binder and pencil for 17 yrs. :). I have used Excel for other thing= s but -- sometimes it's hard to see the obvious. I would like to include th= e event info and distance to my station and also the signal size I record (= P-P). That way I can plot count vs magnitude vs distance with the computer = rather than by hand. Is there a convenient way to import the  winquake= data? I can always do it by hand.
Regards
Barry
 

---= On Fri, 10/23/09, Larry Conklin <lconklin@............> wrote:

From: Larry Conklin <lconklin@t= wcny.rr.com>
Subject: Re: Instument Quality
To: psn-l@............. om
Date: Friday, October 23, 2009, 6:52 AM

Hi Ted,

I have an Excel spreadsheet that I use to record the events I'= ve seen with my SG system.  The sheet includes a magnitude vs distance= scatter plot, with each point color coded (A - D) to represent my (very) s= ubjective assessment of the quality of the detection.  I have a databa= se of over 800 events.

My system is far from an optimal construction= and my location is pretty noisy, but I think overall my results are reason= ably typical of a fair to middlen amateur system.

If you or anyone e= lse would like a copy of the sheet and data to examine for comparison to yo= ur own results, I'd be happy to send it to you. I've included a few other f= eatures, and I use it to manage all of my event files.

Larry

= tchannel wrote:
> I have a follow up question, only somewhat related.=    When the sensor is completed, one of the first questions = a novice might ask is "What can I expect to see"?     I know this would depend, not only the sensor, but many = other things, like the location, and the other components of the station.> We all try to build the best one we can, using the ideas and materia= ls we have.   This site is the best tool I have in my worksh= op.
>  The most common statement I have seen is,  "My senso= r can see >7.0M anywhere in the world"   I have never com= plete a sensor which could not do this.
> I view USGS sites, and find= equipment costing thousands of dollars, pick up more and small events, the= n mine, but not not by much.
> I also know, several of my ideas are n= ot as sensitive as they could be, and some of the ideas simply don't work.&= nbsp;  I learn a lot from both failures and successes.
>&nb= sp; Could someone state, as best as you can "What should I expect to see"?<= br>> Something like:
>  >6.8m anywhere in the world.
>  >6.m within 90 degrees
>  >5.m withi= n 30 degrees   All who have been doing this for a while, kno= w what our equipment will see.   If someone, with really nic= e homebuilt sensors, would share these numbers, it would act, for me, as a = benchmark.
>  Thanks, Ted
>
>    &nb= sp;----- Original Message -----
>     *From:* Ran= dy Pratt <mailto:rpratt@.............>
>&nbs= p;    *To:* psn-l@.............. <mai= lto:psn-l@..............>
>    &= nbsp;*Sent:* Friday, October 23, 2009 12:29 AM
>     *Subject:* Re: Instument Quality
>
>  =    Chris,
>          I apolog= ize for misreading your tone and intent.  It's an
>   =   unfortunate attribute of email that it loses personality. = I agree
>     that a school purchasing an instru= ment for instruction should have a
>     high qua= lity but I don't see that our schools are at that point or
>  &n= bsp;  that caveman is recommending this as a school solution.&nbs= p;         Let me try to explain my sensitivity.  = My son's middle school
>     dropped earth scienc= e to meet state mandates for an increase in
>     = ;physical education hours.  We moved shortly after that to another
= >     state.  Here I became involved with the science fair and to my shock
>     the = largest middle school in the region did not participate.  When I
&g= t;     inquired I found no contract for extra work outs= ide the classroom
>     hours so no science proje= cts.  One high school science teacher
>     = explained to me that there is no time to fit any extra topics in
>&nb= sp;    order to meet federal and state curriculum guidelines= ..  The one
>     teacher that did let me dem= onstrate a seismograph left the area
>     and he= r job was cut.  A German exchange student I am hosting is near
>=      the top of the English class and shows better unde= rstanding than
>     most others according to her= teacher.  She has only been in the
>     US since August so what does that tell you.  Our po= litical mandates
>     are dumbing down the best = students.  It really is approved and
>     b= udgeted science only and that leaves only individual interest.
> = ;         An old magazine article from 1960 something a= bout a smoked drum
>     seismograph stuck in my = mind until I started to research in 1995 and
>    &nbs= p;build my first.  The Lehman article has been the basis for many on>     this list but few of us are using pipe fitti= ngs on a board anymore.     Maybe something simple like= the caveman web page will spark other
>     indi= vidual interest.  How well it functions doesn't matter
>  &= nbsp;  if thinking is set in motion and the steps to reach something better
>     follow.  That's wher= e learning starts.  Think about what percent of
>   &n= bsp; aeronautical engineers started with paper airplanes looping into = the
>     ground and being refolded?   =       Randy
____________________________________________= ______________

Public Seismic Network Mailing List (PSN-L)

To= leave this list email PSN-L-REQUEST@SEISMIC= NET.COM with the body of the message (first line only): unsubscribe
= See h= ttp://www.seismicnet.com/maillist.html for more information.
<= /blockquote>
Subject: Re: instrument design From: "James Allen" jcallen1@........... Date: Fri, 23 Oct 2009 19:14:56 -0700 To Meredith and all, there is a Kinemetrics SH1 currently listed on Ebay = with the case removed so that you can see the mechanism. Jim Allen ----- Original Message -----=20 From: meredith lamb=20 To: psn-l@................. Sent: Wednesday, October 21, 2009 7:56 PM Subject: Re: instrument design On Tue, Oct 20, 2009 at 8:12 AM, Randall Peters = wrote: (Clip) Randall, ** In regard to the Kinemetrics SH-1; I'am having difficulty = visualizing the spring directlyabove the horizontal pendulum mass. Might you and anyone have a PDF file with a = picture/s they could share? A commercial horizontal seismometer that successfully = uses the same physical principle is the Kinemetrics SH-1. The torque = acting in opposition to gravity is provided by means of a vertical = elastic metal strip (spring) that holds the seismic mass in an = equilibrium position directly above it. The instrument employs two = magnet/coil subsystems: (i) one for Faraday law detection with which = every amateur seismologist is familiar, and the (ii) other one for = calibration (by introducing a current to the coil) and for damping when = operational (by placing a resistor across the coil).=20 ** Feel free to offer your thoughts on the sensors. I hae not here mentioned sensor type. For those with interest I can = offer thoughts based on my long-time experience with both velocity and = position types. =20 Randall Peters =20 Meredith Lamb
To Meredith and all, there is a = Kinemetrics SH1=20 currently listed on Ebay with the case removed so that you can see the=20 mechanism.
Jim Allen
----- Original Message -----
From:=20 meredith lamb
Sent: Wednesday, October 21, = 2009 7:56=20 PM
Subject: Re: instrument = design



On Tue, Oct 20, 2009 at 8:12 AM, Randall = Peters <PETERS_RD@..........> = wrote:
 
(Clip)
 
Randall,
 
** In regard to the Kinemetrics SH-1; I'am = having=20 difficulty visualizing the spring directlyabove the
horizontal pendulum mass.  Might you and = anyone=20 have a PDF file with a picture/s they could share?

             = A commercial horizontal seismometer that successfully uses the same = physical=20 principle is the Kinemetrics SH-1.  The torque acting in = opposition to=20 gravity is provided by means of a vertical elastic metal strip = (spring) that=20 holds the seismic mass in an equilibrium position directly above = it. =20 The instrument employs two magnet/coil subsystems: (i) one for = Faraday law=20 detection with which every amateur seismologist is familiar, and the = (ii)=20 other one for calibration (by introducing a current to the coil) and = for=20 damping when operational (by placing a resistor across the coil).=20

** Feel free to = offer your=20 thoughts on the sensors.

I hae not = here mentioned sensor type.  For those = with interest=20 I can offer thoughts based on my long-time experience with both = velocity and=20 position types. 

Randall=20 Peters  

 
Meredith Lamb
 
Subject: Re: Quake data spreadsheet From: Larry Conklin lconklin@............ Date: Fri, 23 Oct 2009 22:36:02 -0400 Hi Barry, I just maintain my spreadsheet database by hand. When I record a new event, I file away the event data and add a corresponding entry to the spreadsheet. I use the spreadsheet as a sort of index into my archive of event data files. What I did was to write a spreadsheet macro that allows me to select an event file name in the sheet and call up Winquake to display that file. Just click it and view it, right from the spreadsheet. I can also pass the file to a home brew program that replays the event on the monitor, and a couple of other things. If you are looking for a way to import the event header data directly from Winquake into a spreadsheet, I don't think there is a simple way to do that. I suppose you could write a program that would scan a directory full of event files and extract selected header data into a set of comma separated fields in a data file that an Excel spreadsheet could then import. Would be in interesting exercise, but not entirely trivial to do it right. Larry Barry Lotz wrote: > Larry > I like the idea. I have been using a spiral binder and pencil for 17 > yrs. :). I have used Excel for other things but -- sometimes it's hard > to see the obvious. I would like to include the event info and distance > to my station and also the signal size I record (P-P). That way I can > plot count vs magnitude vs distance with the computer rather than by > hand. Is there a convenient way to import the winquake data? I can > always do it by hand. > Regards > Barry > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: RE: Quake data spreadsheet From: "Stephen Hammond" shammon1@............. Date: Fri, 23 Oct 2009 20:16:37 -0700 This sounds like something I would like to try, do you mind sharing the excel macro? Steve Hammond PSN Aptos, CA -----Original Message----- From: psn-l-request@.............. [mailto:psn-l-request@............... On Behalf Of Larry Conklin Sent: Friday, October 23, 2009 7:36 PM To: psn-l@.............. Subject: Re: Quake data spreadsheet Hi Barry, I just maintain my spreadsheet database by hand. When I record a new event, I file away the event data and add a corresponding entry to the spreadsheet. I use the spreadsheet as a sort of index into my archive of event data files. What I did was to write a spreadsheet macro that allows me to select an event file name in the sheet and call up Winquake to display that file. Just click it and view it, right from the spreadsheet. I can also pass the file to a home brew program that replays the event on the monitor, and a couple of other things. If you are looking for a way to import the event header data directly from Winquake into a spreadsheet, I don't think there is a simple way to do that. I suppose you could write a program that would scan a directory full of event files and extract selected header data into a set of comma separated fields in a data file that an Excel spreadsheet could then import. Would be in interesting exercise, but not entirely trivial to do it right. Larry Barry Lotz wrote: > Larry > I like the idea. I have been using a spiral binder and pencil for 17 > yrs. :). I have used Excel for other things but -- sometimes it's hard > to see the obvious. I would like to include the event info and distance > to my station and also the signal size I record (P-P). That way I can > plot count vs magnitude vs distance with the computer rather than by > hand. Is there a convenient way to import the winquake data? I can > always do it by hand. > Regards > Barry > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: instrument design From: meredith lamb paleoartifact@......... Date: Fri, 23 Oct 2009 22:38:07 -0600 Hi James, Thanks very much for the E-Bay note on the seismometer! The pictures were ~ vague, but I think I see the flat metal strip on top. Interesting hanging mass approach. I am "speculating" that it has a photo sensor on the bottom for rough centering purposes? The seller may send a PDF file on such which might also give more overall insight. Makes me wonder whether a round piano wire that replaces the flat metal strip would work out? Meredith On Fri, Oct 23, 2009 at 8:14 PM, James Allen wrote: > To Meredith and all, there is a Kinemetrics SH1 currently listed on Ebay > with the case removed so that you can see the mechanism. > Jim Allen > > > >
Hi James,
=A0
Thanks very much for the E-Bay note on the seismometer!=A0 The picture= s were ~ vague, but I think I see the flat metal strip on top.=A0 Interesti= ng hanging mass approach.=A0 I am "speculating" that it has a pho= to sensor
on the bottom for rough centering purposes?=A0 The=A0seller may send a= PDF file=A0on such which might
also give more overall insight.=A0
=A0
Makes me wonder=A0whether a round piano wire that replaces the flat me= tal strip would work out?
=A0
Meredith=A0

On Fri, Oct 23, 2009 at 8:14 PM, James Allen <jcallen1@verizon= ..net> wrote:
To Meredith and all, there is a Kineme= trics SH1 currently listed on Ebay with the case removed so that you can se= e the mechanism.
Jim Allen
=A0
Subject: Re: Quake data spreadsheet From: Larry Conklin lconklin@............ Date: Sat, 24 Oct 2009 09:22:37 -0400 Hi Setephen, Below is a copy of the macro, cut & pasted right out of the spreadsheet. The basic idea is to use the VBA Shell() function to call an external program and pass the name of the file to be executed as a command line argument. You could do this with most anthing, provided that the program you pick expects command line arguments. Take note that some of the lines in the code got folded to fit this e-mail. (Ie. DataFilePath =.... , ExecutablePath = ... , ProcID = ...) If you want to try it out I'd be happy to send you a copy of the whole thing, along with a little file of "user notes" that I put together. One little Winquake enhancement I'd love to see (hint, hint) is the capability to take more than file name argument on the command line. You can already select more than one file in the file open dialog box, and if the files are compatable (same time parameters) they open together, which allows direct comparison and manipulation of the two files. If I use my spreadsheet to open more than one file, both open in their own windows in Winquake, but any manipulations in one file window do not affect the other. Larry Sub RunWinquake() ' ' Pass a selected event file to Winquake for execution. The ' event file is selected by selecting the event file name in ' the spreadsheet. ' Dim ProcID Dim DataFilePath As String Dim ExecutablePath As String DataFilePath = Environ("WQPATH") & Range("Notes!D20").Value & Left(ActiveCell.Value, 2) & "\" ExecutablePath = Environ("WQPATH") & Range("Notes!D23").Value ProcID = Shell(PathName:=ExecutablePath & " " & DataFilePath & ActiveCell.Value, WindowStyle:=vbNormalFocus) End Sub Stephen Hammond wrote: > This sounds like something I would like to try, do you mind sharing the > excel macro? > Steve Hammond PSN Aptos, CA > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: RE: Quake data spreadsheet From: "Stephen Hammond" shammon1@............. Date: Sat, 24 Oct 2009 09:57:06 -0700 Thanks Larry I'll print it off and play with this and see what I can do with it. Like many, I have a directory full of event files and one of the thing I would like to see winquake do (hint-hint <<>>) is have it add the complete header directly to an existing exec spreadsheet in the winquake subdir via a command key in winquake. I think this would be really handy and enable us to do data analysis without a lot of effort to extract the header and move it into a spreedsheet. Thanks a lot-- Steve Hammond -----Original Message----- From: psn-l-request@.............. [mailto:psn-l-request@............... On Behalf Of Larry Conklin Sent: Saturday, October 24, 2009 6:23 AM To: psn-l@.............. Subject: Re: Quake data spreadsheet Hi Setephen, Below is a copy of the macro, cut & pasted right out of the spreadsheet. The basic idea is to use the VBA Shell() function to call an external program and pass the name of the file to be executed as a command line argument. You could do this with most anthing, provided that the program you pick expects command line arguments. Take note that some of the lines in the code got folded to fit this e-mail. (Ie. DataFilePath =.... , ExecutablePath = ... , ProcID = ...) If you want to try it out I'd be happy to send you a copy of the whole thing, along with a little file of "user notes" that I put together. One little Winquake enhancement I'd love to see (hint, hint) is the capability to take more than file name argument on the command line. You can already select more than one file in the file open dialog box, and if the files are compatable (same time parameters) they open together, which allows direct comparison and manipulation of the two files. If I use my spreadsheet to open more than one file, both open in their own windows in Winquake, but any manipulations in one file window do not affect the other. Larry Sub RunWinquake() ' ' Pass a selected event file to Winquake for execution. The ' event file is selected by selecting the event file name in ' the spreadsheet. ' Dim ProcID Dim DataFilePath As String Dim ExecutablePath As String DataFilePath = Environ("WQPATH") & Range("Notes!D20").Value & Left(ActiveCell.Value, 2) & "\" ExecutablePath = Environ("WQPATH") & Range("Notes!D23").Value ProcID = Shell(PathName:=ExecutablePath & " " & DataFilePath & ActiveCell.Value, WindowStyle:=vbNormalFocus) End Sub Stephen Hammond wrote: > This sounds like something I would like to try, do you mind sharing the > excel macro? > Steve Hammond PSN Aptos, CA > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: RE: Quake data spreadsheet From: Barry Lotz barry_lotz@............. Date: Sat, 24 Oct 2009 10:21:36 -0700 (PDT) Steve I second the motion. What if a window came up and you could check boxes for= the header data you wanted to transfer?=20 Barry --- On Sat, 10/24/09, Stephen Hammond wrote: From: Stephen Hammond Subject: RE: Quake data spreadsheet To: psn-l@.............. Date: Saturday, October 24, 2009, 9:57 AM Thanks Larry I'll print it off and play with this and see what I can do wit= h it. Like many, I have a directory full of event files and one of the thing = I would like to see winquake do (hint-hint <<>>) is have it add the complete header directly to an existing exec spreadsheet in the winquake subdir via a command key in winquake. I think this would be really handy an= d enable us to do data analysis without a lot of effort to extract the header and move it into a spreedsheet.=20 Thanks a lot-- Steve Hammond -----Original Message----- From: psn-l-request@.............. [mailto:psn-l-request@............... On Behalf Of Larry Conklin Sent: Saturday, October 24, 2009 6:23 AM To: psn-l@.............. Subject: Re: Quake data spreadsheet Hi Setephen, Below is a copy of the macro, cut & pasted right out of the spreadsheet.=20 =A0 The basic idea is to use the VBA Shell() function to call an external= =20 program and pass the name of the file to be executed as a command line=20 argument.=A0 You could do this with most anthing, provided that the=20 program you pick expects command line arguments.=A0 Take note that some of= =20 the lines in the code got folded to fit this e-mail.=A0 (Ie. DataFilePath= =20 =3D.... , ExecutablePath =3D ... , ProcID =3D ...) If you want to try it out I'd be happy to send you a copy of the whole=20 thing, along with a little file of "user notes" that I put together. One little Winquake enhancement I'd love to see (hint, hint) is the=20 capability to take more than file name argument on the command line.=20 You can already select more than one file in the file open dialog box,=20 and if the files are compatable (same time parameters) they open=20 together, which allows direct comparison and manipulation of the two=20 files.=A0 If I use my spreadsheet to open more than one file, both open in= =20 their own windows in Winquake, but any manipulations in one file window=20 do not affect the other. Larry Sub RunWinquake() ' ' Pass a selected event file to Winquake for execution.=A0 The ' event file is selected by selecting the event file name in ' the spreadsheet. ' Dim ProcID Dim DataFilePath=A0 =A0 As String Dim ExecutablePath=A0 As String DataFilePath =3D Environ("WQPATH") & Range("Notes!D20").Value & Left(ActiveCell.Value, 2) & "\" ExecutablePath =3D Environ("WQPATH") & Range("Notes!D23").Value ProcID =3D Shell(PathName:=3DExecutablePath & " " & DataFilePath &=20 ActiveCell.Value, WindowStyle:=3DvbNormalFocus) End Sub Stephen Hammond wrote: > This sounds like something I would like to try, do you mind sharing the > excel macro? > Steve Hammond=A0 PSN Aptos, CA >=20 __________________________________________________________ Public Seismic Network Mailing List (PSN-L) __________________________________________________________ Public Seismic Network Mailing List (PSN-L)
Steve
I second the motion. What if a windo= w came up and you could check boxes for the header data you wanted to trans= fer?
Barry

--- On Sat, 10/24/09, Stephen Hammond <shamm= on1@.............> wrote:

From: = Stephen Hammond <shammon1@.............>
Subject: RE: Quake data s= preadsheet
To: psn-l@..............
Date: Saturday, October 24, 2009,= 9:57 AM

Thanks Larry I'll print it off and= play with this and see what I can do with
it. Like many, I have a direc= tory full of event files and one of the thing I
would like to see winqua= ke do (hint-hint <<<Grin>>>) is have it add the
comple= te header directly to an existing exec spreadsheet in the winquake
subdi= r via a command key in winquake. I think this would be really handy and
enable = us to do data analysis without a lot of effort to extract the header
and= move it into a spreedsheet.

Thanks a lot-- Steve Hammond

--= ---Original Message-----
From: psn-l-requ= est@.............. [mailto:psn-l-request= @..............] On
Behalf Of Larry Conklin
Sent: Saturday, Octob= er 24, 2009 6:23 AM
To: psn-l@..............
Subj= ect: Re: Quake data spreadsheet

Hi Setephen,

Below is a copy = of the macro, cut & pasted right out of the spreadsheet.
  The= basic idea is to use the VBA Shell() function to call an external
prog= ram and pass the name of the file to be executed as a command line
argument.  = You could do this with most anthing, provided that the
program you pick= expects command line arguments.  Take note that some of
the lines= in the code got folded to fit this e-mail.  (Ie. DataFilePath
=3D= ..... , ExecutablePath =3D ... , ProcID =3D ...)

If you want to try i= t out I'd be happy to send you a copy of the whole
thing, along with a = little file of "user notes" that I put together.

One little Winquake= enhancement I'd love to see (hint, hint) is the
capability to take mor= e than file name argument on the command line.
You can already select m= ore than one file in the file open dialog box,
and if the files are com= patable (same time parameters) they open
together, which allows direct = comparison and manipulation of the two
files.  If I use my spreads= heet to open more than one file, both open in
their own windows in Winquake, but any manipulations in one file window
do not affect the o= ther.

Larry


Sub RunWinquake()
'
' Pass a selected e= vent file to Winquake for execution.  The
' event file is selected = by selecting the event file name in
' the spreadsheet.
'
Dim ProcI= D
Dim DataFilePath    As String
Dim ExecutablePath  As= String

DataFilePath =3D Environ("WQPATH") & Range("Notes!D20").= Value &
Left(ActiveCell.Value, 2) & "\"
ExecutablePath =3D En= viron("WQPATH") & Range("Notes!D23").Value

ProcID =3D Shell(Path= Name:=3DExecutablePath & " " & DataFilePath &
ActiveCell.Va= lue, WindowStyle:=3DvbNormalFocus)

End Sub

Stephen Hammond wr= ote:
> This sounds like something I would like to try, do you mind sh= aring the
> excel macro?
> Steve Hammond  PSN Aptos, CA>
__________________________________________________________

Publ= ic Seismic Network Mailing List (PSN-L)

To leave this list email PSN-L-REQUEST@.............. with
the b= ody of the message (first line only): unsubscribe
See http://www.seismicnet.c= om/maillist.html for more information.

_________________________= _________________________________

Public Seismic Network Mailing Lis= t (PSN-L)

To leave this list email PS= N-L-REQUEST@.............. with
the body of the message (first line= only): unsubscribe
See http://www.seismicnet.com/maillist.html for more information.
Subject: Re: instrument design From: Robert McClure bobmcclure90@......... Date: Sat, 24 Oct 2009 13:26:46 -0400 It looks like an inverted pendulum to me, with a spring hinge at the bottom. On 10/24/09, meredith lamb wrote: > Hi James, > > Thanks very much for the E-Bay note on the seismometer! The pictures were ~ > vague, but I think I see the flat metal strip on top. Interesting hanging > mass approach. I am "speculating" that it has a photo sensor > on the bottom for rough centering purposes? The seller may send a PDF > file on such which might > also give more overall insight. > > Makes me wonder whether a round piano wire that replaces the flat metal > strip would work out? > > Meredith > > On Fri, Oct 23, 2009 at 8:14 PM, James Allen wrote: > >> To Meredith and all, there is a Kinemetrics SH1 currently listed on Ebay >> with the case removed so that you can see the mechanism. >> Jim Allen >> >> >> >> > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: instrument design From: "tchannel" tchannel@............ Date: Sat, 24 Oct 2009 12:32:39 -0600 I do not see this on ebay, could you send me the item #? tchannel@............ Thanks, Ted ----- Original Message ----- From: "Robert McClure" To: Sent: Saturday, October 24, 2009 11:26 AM Subject: Re: instrument design > It looks like an inverted pendulum to me, with a spring hinge at the > bottom. > > On 10/24/09, meredith lamb wrote: >> Hi James, >> >> Thanks very much for the E-Bay note on the seismometer! The pictures >> were ~ >> vague, but I think I see the flat metal strip on top. Interesting >> hanging >> mass approach. I am "speculating" that it has a photo sensor >> on the bottom for rough centering purposes? The seller may send a PDF >> file on such which might >> also give more overall insight. >> >> Makes me wonder whether a round piano wire that replaces the flat metal >> strip would work out? >> >> Meredith >> >> On Fri, Oct 23, 2009 at 8:14 PM, James Allen >> wrote: >> >>> To Meredith and all, there is a Kinemetrics SH1 currently listed on >>> Ebay >>> with the case removed so that you can see the mechanism. >>> Jim Allen >>> >>> >>> >>> >> > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: instrument design From: meredith lamb paleoartifact@......... Date: Sat, 24 Oct 2009 13:05:44 -0600 Hi all, The E-Bay # is 180423674973 however it was sold. The pictures are still there for viewing, if one goes down the page thereon. However, the patent number is known, which gives insight into the mechanical design for such a small instrument; to derive such a long ~ 5 second period, in case anybody is interested. The patent number is 3,685,011 and it can readily be seen on the Google Patents search program. Go to the Google search engine, clich the "other" link and go down to the Patents search program and enter in the patent number. One can fully review the text and drawings and download such with no fuss. My initial "impression" is that it is kind of a "mix" of the old Wechert (with the springs much lower), and even possibly "somewhat" like a gravitational pendulum of more recent design....if, the mass pendulum can be raised or lowered on the boom. Its a very interesting design which ~ might even be useful for a unidirectional sensor application; i.e., N-S and/or E-W, all in one instrument...but I suppose that possiblity might be taking it too far for whatever various reason/s. Take care, Meredith Lamb On Sat, Oct 24, 2009 at 12:32 PM, tchannel wrote: > I do not see this on ebay, could you send me the item #? > > tchannel@............ > > Thanks, Ted > > > ----- Original Message ----- From: "Robert McClure" < > bobmcclure90@.........> > > To: > Sent: Saturday, October 24, 2009 11:26 AM > Subject: Re: instrument design > > > > It looks like an inverted pendulum to me, with a spring hinge at the >> bottom. >> >> On 10/24/09, meredith lamb wrote: >> >>> Hi James, >>> >>> Thanks very much for the E-Bay note on the seismometer! The pictures >>> were ~ >>> vague, but I think I see the flat metal strip on top. Interesting >>> hanging >>> mass approach. I am "speculating" that it has a photo sensor >>> on the bottom for rough centering purposes? The seller may send a PDF >>> file on such which might >>> also give more overall insight. >>> >>> Makes me wonder whether a round piano wire that replaces the flat metal >>> strip would work out? >>> >>> Meredith >>> >>> On Fri, Oct 23, 2009 at 8:14 PM, James Allen >>> wrote: >>> >>> To Meredith and all, there is a Kinemetrics SH1 currently listed on Ebay >>>> with the case removed so that you can see the mechanism. >>>> Jim Allen >>>> >>>> >>>> >>>> >>>> >>> __________________________________________________________ >> >> Public Seismic Network Mailing List (PSN-L) >> >> To leave this list email PSN-L-REQUEST@.............. with >> the body of the message (first line only): unsubscribe >> See http://www.seismicnet.com/maillist.html for more information. >> > > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with the body of the > message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. >
Hi all,
=A0
The E-Bay # is 180423674973 however it was sold.=A0 The pictures are s= till there for viewing, if one
goes down the page thereon.
=A0
However, the patent number is known, which gives
insight into the mechanical design for such a small instrument; to der= ive such a long=A0~ 5 second period,
in case anybody is interested.=A0 The patent number is 3,685,011 and i= t can readily be seen on the Google
Patents search program.=A0 Go to the Google search engine, clich the &= quot;other" link and go down to the=A0
Patents search=A0program and enter in the patent number.=A0 One can fu= lly review the text and drawings and
download such with no fuss.=A0=A0My initial "impression" is = that it is kind of a "mix" of the old Wechert (with the springs m= uch lower), and even possibly "somewhat" like a gravitational pen= dulum of more recent design....if,
the mass pendulum can be raised or lowered on the boom.=A0 Its a very = interesting design which ~ might
even be useful for a unidirectional sensor application; i.e., N-S=A0an= d/or E-W, all in one instrument...but=A0I
suppose that possiblity might be taking it too far for whatever variou= s reason/s.=A0
=A0
Take care, Meredith Lamb
=A0
On Sat, Oct 24, 2009 at 12:32 PM, tchannel <tchannel@............> wrote:
I do not see this on ebay, could= you send me the item #?

tchannel@............

Thanks, Ted


----- Original Message ----- From: "Robert = McClure" <bobmcclure90@.........>=20 Sent: Saturday, October 24, 2009 11:2= 6 AM
Subject: Re: instrument design=20



=A0It looks like an inverted pen= dulum to me, with a spring hinge at the bottom.

On 10/24/09, meredit= h lamb <pal= eoartifact@.........> wrote:
Hi James,

Thanks very muc= h for the E-Bay note on the seismometer! =A0The pictures were ~
vague, b= ut I think I see the flat metal strip on top. =A0Interesting hanging
mass approach. =A0I am "speculating" that it has a photo sensoron the bottom for rough centering purposes? =A0The seller may send a PDF<= br>file on such which might
also give more overall insight.

Makes= me wonder whether a round piano wire that replaces the flat metal
strip would work out?

Meredith

On Fri, Oct 23, 2009 at 8:14 P= M, James Allen <jcallen1@...........> wrote:

=A0To Meredith and all, there is= a Kinemetrics SH1 currently listed on Ebay
with the case removed so tha= t you can see the mechanism.
Jim Allen





________________= __________________________________________

Public Seismic Network Ma= iling List (PSN-L)

To leave this list email PSN-L-REQUEST@.............. = with
the body of the message (first line only): unsubscribe
See http://www.seismic= net.com/maillist.html for more information.

______= ____________________________________________________

Public Seismic Network Mailing List (PSN-L)

To leave this list e= mail PSN-= L-REQUEST@.............. with the body of the message (first line only)= : unsubscribe
See h= ttp://www.seismicnet.com/maillist.html for more information.
<= /div>

Subject: Re: instrument design From: Brett Nordgren brett3nt@............. Date: Sat, 24 Oct 2009 15:20:10 -0400 Hi, I have a pdf of that patent http://bnordgren.org/seismo/us003685011.pdf which is quite detailed, so long as you don't mind reading the "patentese" text. Brett At 01:05 PM 10/24/2009 -0600, you wrote: >Hi all, > >The E-Bay # is 180423674973 however it was sold. The pictures are still >there for viewing, if one >goes down the page thereon. > >However, the patent number is known, which gives >insight into the mechanical design for such a small instrument; to derive >such a long ~ 5 second period, >in case anybody is interested. The patent number is 3,685,011 and it can >readily be seen on the Google >Patents search program. Watch our wiggles http://bnordgren.org/seismo/gif_images.htm or watch some very very good wiggles http://aslwww.cr.usgs.gov/Seismic_Data/telemetry_data/ANMO_24hr.html __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Instrument quality - microseisms From: Stephen & Kathy skmort@............ Date: Sat, 24 Oct 2009 12:33:38 -0700 FYI, the following Navy weather site gives a little= more info on ocean waves, including period, for those who may want to try and see a correlation with seismo waveform???

It is a little more involved than the link I sent the other day, getting to the info, but if you play with it for a while you will figure it out.=A0 For example, once you click on an icon, it will take you to a short list of choices; =A0 Here, if you click on a single "time"= button, rather than an "all" button, you will get a list to the left side of the chart for a lot more info for different types of waves and periods; along with other weather choices.
https://www.fnmoc.navy.mil/ww3_cgi/index.html

Here is a link to a story where they intend to use seismograms to try and find unrecorded historical hurricanes.
http://www.geosociety.org/news/pr/09-60.htm
=A0 Enjoy,=A0 Stephen
=A0 PSN Station #55
=A0 38.828N=A0 120.979W
=A0 near Pilot Hill Ca. USA


Subject: TELEDYNE-GEOTECH HELICORDER From: "James Allen" jcallen1@........... Date: Sat, 24 Oct 2009 12:56:46 -0700 Does anyone have or know of a place where I can obtain a replacement ink = dispensing writing stylus for a Teledyne-Geotech Helicorder? Thanks James Allen ----- Original Message -----=20 From: meredith lamb=20 To: psn-l@................. Sent: Saturday, October 24, 2009 12:05 PM Subject: Re: instrument design Hi all, The E-Bay # is 180423674973 however it was sold. The pictures are = still there for viewing, if one goes down the page thereon. However, the patent number is known, which gives insight into the mechanical design for such a small instrument; to = derive such a long ~ 5 second period, in case anybody is interested. The patent number is 3,685,011 and it = can readily be seen on the Google Patents search program. Go to the Google search engine, clich the = "other" link and go down to the=20 Patents search program and enter in the patent number. One can fully = review the text and drawings and download such with no fuss. My initial "impression" is that it is = kind of a "mix" of the old Wechert (with the springs much lower), and = even possibly "somewhat" like a gravitational pendulum of more recent = design....if, the mass pendulum can be raised or lowered on the boom. Its a very = interesting design which ~ might even be useful for a unidirectional sensor application; i.e., N-S = and/or E-W, all in one instrument...but I suppose that possiblity might be taking it too far for whatever = various reason/s.=20 Take care, Meredith Lamb On Sat, Oct 24, 2009 at 12:32 PM, tchannel = wrote: I do not see this on ebay, could you send me the item #? tchannel@............ Thanks, Ted ----- Original Message ----- From: "Robert McClure" = =20 To: Sent: Saturday, October 24, 2009 11:26 AM Subject: Re: instrument design=20 It looks like an inverted pendulum to me, with a spring hinge at = the bottom. On 10/24/09, meredith lamb wrote: Hi James, Thanks very much for the E-Bay note on the seismometer! The = pictures were ~ vague, but I think I see the flat metal strip on top. = Interesting hanging mass approach. I am "speculating" that it has a photo sensor on the bottom for rough centering purposes? The seller may send = a PDF file on such which might also give more overall insight. Makes me wonder whether a round piano wire that replaces the = flat metal strip would work out? Meredith On Fri, Oct 23, 2009 at 8:14 PM, James Allen = wrote: To Meredith and all, there is a Kinemetrics SH1 currently = listed on Ebay with the case removed so that you can see the mechanism. Jim Allen __________________________________________________________ Public Seismic Network Mailing List (PSN-L) To leave this list email PSN-L-REQUEST@.............. with the body of the message (first line only): unsubscribe See http://www.seismicnet.com/maillist.html for more information.=20 __________________________________________________________ Public Seismic Network Mailing List (PSN-L) To leave this list email PSN-L-REQUEST@.............. with the body = of the message (first line only): unsubscribe See http://www.seismicnet.com/maillist.html for more information.
Does anyone have or know of a place = where I can=20 obtain a replacement ink dispensing writing stylus for a = Teledyne-Geotech=20 Helicorder?
Thanks
James Allen
----- Original Message -----
From:=20 meredith lamb
Sent: Saturday, October 24, = 2009 12:05=20 PM
Subject: Re: instrument = design

Hi all,
 
The E-Bay # is 180423674973 however it was sold.  The = pictures are=20 still there for viewing, if one
goes down the page thereon.
 
However, the patent number is known, which gives
insight into the mechanical design for such a small instrument; = to derive=20 such a long ~ 5 second period,
in case anybody is interested.  The patent number is = 3,685,011 and=20 it can readily be seen on the Google
Patents search program.  Go to the Google search engine, = clich the=20 "other" link and go down to the 
Patents search program and enter in the patent number.  = One can=20 fully review the text and drawings and
download such with no fuss.  My initial "impression" is = that it=20 is kind of a "mix" of the old Wechert (with the springs much lower), = and even=20 possibly "somewhat" like a gravitational pendulum of more recent=20 design....if,
the mass pendulum can be raised or lowered on the boom.  Its = a very=20 interesting design which ~ might
even be useful for a unidirectional sensor application; i.e.,=20 N-S and/or E-W, all in one instrument...but I
suppose that possiblity might be taking it too far for whatever = various=20 reason/s. 
 
Take care, Meredith Lamb
 
On Sat, Oct 24, 2009 at 12:32 PM, tchannel = <tchannel@............> wrote:
I do not see this on ebay, could you send me the = item=20 #?

tchannel@............

Thanks, = Ted


-----=20 Original Message ----- From: "Robert McClure" <bobmcclure90@.........>=20 Sent: = Saturday, October=20 24, 2009 11:26 AM
Subject: Re: instrument design=20



 It looks like an inverted pendulum to me, = with a=20 spring hinge at the bottom.

On 10/24/09, meredith lamb = <paleoartifact@.........> wrote:
Hi James,

Thanks very much for the = E-Bay note=20 on the seismometer!  The pictures were ~
vague, but I = think I=20 see the flat metal strip on top.  Interesting = hanging
mass=20 approach.  I am "speculating" that it has a photo = sensor
on the=20 bottom for rough centering purposes?  The seller may send a = PDF
file on such which might
also give more overall=20 insight.

Makes me wonder whether a round piano wire that = replaces=20 the flat metal
strip would work = out?

Meredith

On Fri,=20 Oct 23, 2009 at 8:14 PM, James Allen <jcallen1@...........> wrote:

 To Meredith and all, there is a = Kinemetrics=20 SH1 currently listed on Ebay
with the case removed so that = you can=20 see the mechanism.
Jim=20 = Allen





__________________= ________________________________________

Public=20 Seismic Network Mailing List (PSN-L)

To leave this list = email PSN-L-REQUEST@.............. with
the body = of the=20 message (first line only): unsubscribe
See http://www.seismicnet.com/maillist.html for = more=20 information.=20 =

____________________________________________________= ______

Public=20 Seismic Network Mailing List (PSN-L)

To leave this list email = PSN-L-REQUEST@.............. with the body of = the message=20 (first line only): unsubscribe
See http://www.seismicnet.com/maillist.html for more = = information.

Subject: Re: instrument design From: meredith lamb paleoartifact@......... Date: Sat, 24 Oct 2009 14:13:24 -0600 Hi Brett and all, Excellent PDF file there; thanks for sharing! The E-Bay seller advises me that each coil is ~ 1975 ohms each; and that it has a .4 ohm calibration coil thereon also....perhaps some info that might not be on the patent info and such. Meredith Lamb On Sat, Oct 24, 2009 at 1:20 PM, Brett Nordgren wrote: > Hi, > > I have a pdf of that patent http://bnordgren.org/seismo/us003685011.pdf which is quite detailed, so long as you don't mind reading the "patentese" > text. > > Brett > > > > At 01:05 PM 10/24/2009 -0600, you wrote: > >> Hi all, >> >> The E-Bay # is 180423674973 however it was sold. The pictures are still >> there for viewing, if one >> goes down the page thereon. >> >> However, the patent number is known, which gives >> insight into the mechanical design for such a small instrument; to derive >> such a long ~ 5 second period, >> in case anybody is interested. The patent number is 3,685,011 and it can >> readily be seen on the Google >> Patents search program. >> > > > > Watch our wiggles > http://bnordgren.org/seismo/gif_images.htm > > or watch some very very good wiggles > http://aslwww.cr.usgs.gov/Seismic_Data/telemetry_data/ANMO_24hr.html > > > > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with the body of the > message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. >
Hi Brett and all,
=A0
Excellent PDF file there; thanks for sharing!
=A0
The E-Bay seller advises me that=A0each coil is ~ 1975 ohms each; and = that it has a .4 ohm calibration
coil thereon also....perhaps some info that might not be on the patent= info and such.
=A0
Meredith Lamb=A0=A0=A0=A0

On Sat, Oct 24, 2009 at 1:20 PM, Brett Nordgren = <brett3nt@.............> wrote:
Hi,

I have a pdf of that = patent =A0http://bnordgren.org/seismo/us003685011.pdf =A0which is quite = detailed, so long as you don't mind reading the "patentese" t= ext.

Brett=20



At 01:05 PM 10/24/2009 -0600, you wrote:
Hi all,

The E-Bay # is 18= 0423674973 however it was sold. =A0The pictures are still there for viewing= , if one
goes down the page thereon.

However, the patent number is known, whi= ch gives
insight into the mechanical design for such a small instrument;= to derive such a long ~ 5 second period,
in case anybody is interested.= =A0The patent number is 3,685,011 and it can readily be seen on the Google=
Patents search program.

<clip>

Watch= our wiggles
http://bnordgren.org/seismo/gif_images.htm

or watc= h some very very good wiggles
http://aslwww.cr.usgs.gov/Seismic_Data/telemetry_da= ta/ANMO_24hr.html=20



__________________________________________________________=

Public Seismic Network Mailing List (PSN-L)

To leave this li= st email = PSN-L-REQUEST@.............. with the body of the message (first line o= nly): unsubscribe
See h= ttp://www.seismicnet.com/maillist.html for more information.
<= /div>

Subject: Re: TELEDYNE-GEOTECH HELICORDER From: AHrubetz@....... Date: Sat, 24 Oct 2009 16:28:42 EDT James, Try Geotech Instruments in Dallas, phone 214-221-0000. Al In a message dated 10/24/2009 2:57:11 P.M. Central Daylight Time, jcallen1@........... writes: Does anyone have or know of a place where I can obtain a replacement ink dispensing writing stylus for a Teledyne-Geotech Helicorder? Thanks James Allen ----- Original Message ----- From: _meredith lamb_ (mailto:paleoartifact@.......... To: _psn-l@............... (mailto:psn-l@............... Sent: Saturday, October 24, 2009 12:05 PM Subject: Re: instrument design Hi all, The E-Bay # is 180423674973 however it was sold. The pictures are still there for viewing, if one goes down the page thereon. However, the patent number is known, which gives insight into the mechanical design for such a small instrument; to derive such a long ~ 5 second period, in case anybody is interested. The patent number is 3,685,011 and it can readily be seen on the Google Patents search program. Go to the Google search engine, clich the "other" link and go down to the Patents search program and enter in the patent number. One can fully review the text and drawings and download such with no fuss. My initial "impression" is that it is kind of a "mix" of the old Wechert (with the springs much lower), and even possibly "somewhat" like a gravitational pendulum of more recent design....if, the mass pendulum can be raised or lowered on the boom. Its a very interesting design which ~ might even be useful for a unidirectional sensor application; i.e., N-S and/or E-W, all in one instrument...but I suppose that possiblity might be taking it too far for whatever various reason/s. Take care, Meredith Lamb On Sat, Oct 24, 2009 at 12:32 PM, tchannel <_tchannel@............. (mailto:tchannel@............. > wrote: I do not see this on ebay, could you send me the item #? _tchannel@............. (mailto:tchannel@............. Thanks, Ted ----- Original Message ----- From: "Robert McClure" <_bobmcclure90@.......... (mailto:bobmcclure90@.......... > To: <_psn-l@............... (mailto:psn-l@............... > Sent: Saturday, October 24, 2009 11:26 AM Subject: Re: instrument design It looks like an inverted pendulum to me, with a spring hinge at the bottom. On 10/24/09, meredith lamb <_paleoartifact@.......... (mailto:paleoartifact@.......... > wrote: Hi James, Thanks very much for the E-Bay note on the seismometer! The pictures were ~ vague, but I think I see the flat metal strip on top. Interesting hanging mass approach. I am "speculating" that it has a photo sensor on the bottom for rough centering purposes? The seller may send a PDF file on such which might also give more overall insight. Makes me wonder whether a round piano wire that replaces the flat metal strip would work out? Meredith On Fri, Oct 23, 2009 at 8:14 PM, James Allen <_jcallen1@............ (mailto:jcallen1@............ > wrote: To Meredith and all, there is a Kinemetrics SH1 currently listed on Ebay with the case removed so that you can see the mechanism. Jim Allen __________________________________________________________ Public Seismic Network Mailing List (PSN-L) To leave this list email _PSN-L-REQUEST@............... (mailto:PSN-L-REQUEST@............... with the body of the message (first line only): unsubscribe See _http://www.seismicnet.com/maillist.html_ (http://www.seismicnet.com/maillist.html) for more information. __________________________________________________________ Public Seismic Network Mailing List (PSN-L) To leave this list email _PSN-L-REQUEST@............... (mailto:PSN-L-REQUEST@............... with the body of the message (first line only): unsubscribe See _http://www.seismicnet.com/maillist.html_ (http://www.seismicnet.com/maillist.html) for more information.
James,
Try Geotech Instruments in Dallas, phone=20 214-221-0000.
 Al
 
In a message dated 10/24/2009 2:57:11 P.M. Central Daylight Time,=20 jcallen1@........... writes:
Does anyone have or know of a place whe= re I can=20 obtain a replacement ink dispensing writing stylus for a Teledyne-Geotec= h=20 Helicorder?
Thanks
James Allen
----- Original Message -----
= From:=20 meredith lamb
To: psn-l@..............
Sent: Saturday, October 24, 200= 9 12:05=20 PM
Subject: Re: instrument design<= /DIV>

Hi all,
 
The E-Bay # is 180423674973 however it was sold.  The pictur= es are=20 still there for viewing, if one
goes down the page thereon.
 
However, the patent number is known, which gives
insight into the mechanical design for such a small instrument;= to=20 derive such a long ~ 5 second period,
in case anybody is interested.  The patent number is 3,685,0= 11 and=20 it can readily be seen on the Google
Patents search program.  Go to the Google search engine, cli= ch the=20 "other" link and go down to the 
Patents search program and enter in the patent number. = One=20 can fully review the text and drawings and
download such with no fuss.  My initial "impression" is= that=20 it is kind of a "mix" of the old Wechert (with the springs much lower)= , and=20 even possibly "somewhat" like a gravitational pendulum of more recent= =20 design....if,
the mass pendulum can be raised or lowered on the boom.  Its= a=20 very interesting design which ~ might
even be useful for a unidirectional sensor application; i.e.,=20 N-S and/or E-W, all in one instrument...but I
suppose that possiblity might be taking it too far for whatever= various=20 reason/s. 
 
Take care, Meredith Lamb
 
On Sat, Oct 24, 2009 at 12:32 PM, tchannel <tchannel@............> wrote:
I do not see this on ebay, could you send me the= item=20 #?

tchannel@............

Thanks,=20 Ted


----- Original Message ----- From: "Robert McClure"= <bobmcclure90@.........>=20 Sent: Saturday= ,=20 October 24, 2009 11:26 AM
Subject: Re: instrument design=20



 It looks like an inverted pendulum to me,= with a=20 spring hinge at the bottom.

On 10/24/09, meredith lamb <= paleoartifact@.........> wrote:
Hi James,

Thanks very much for the E-Ba= y note=20 on the seismometer!  The pictures were ~
vague, but I th= ink I=20 see the flat metal strip on top.  Interesting hanging
ma= ss=20 approach.  I am "speculating" that it has a photo sensoron=20 the bottom for rough centering purposes?  The seller may se= nd a=20 PDF
file on such which might
also give more overall=20 insight.

Makes me wonder whether a round piano wire that= =20 replaces the flat metal
strip would work=20 out?

Meredith

On Fri, Oct 23, 2009 at 8:14 PM, Jam= es=20 Allen <jcallen1@...........> wrote:

 To Meredith and all, there is a Kineme= trics=20 SH1 currently listed on Ebay
with the case removed so that= you=20 can see the mechanism.
Jim=20 Allen





_________= _________________________________________________

Public=20 Seismic Network Mailing List (PSN-L)

To leave this list ema= il PSN-L-REQUEST@.............. with
the body= of the=20 message (first line only): unsubscribe
See http://www.seismicnet.com/maillist.html for mo= re=20 information.=20

_______________________________________________= ___________

Public=20 Seismic Network Mailing List (PSN-L)

To leave this list email= PSN-L-REQUEST@.............. with the body of th= e=20 message (first line only): unsubscribe
See http://www.seismicnet.com/maillist.html for more= =20 information.

 Subject: Re: TELEDYNE-GEOTECH HELICORDER From: meredith lamb paleoartifact@......... Date: Sat, 24 Oct 2009 15:38:34 -0600 James, Perhaps Geotech might have such as Al Hrubetz suggests...but being as ink stylus writing went out long ago...one may have to resort to other (surplus...read: junk or unknown condition substitutes) brands. The tips of worn pens usually gets worn out or abrasively flattened to where the ink flow smears all over the place; rather than flow evenly and write with little snagging "sharpened" pen tip effect...as you likely already know. I've never figured out how to "round out" or "smooth the outside and inside" of the writing tips to effectively, re-use such. Sometimes....the pen tip isn't exactly flat to the writing drum surface (the prior tube gets bent up, down or sideways...and this condition will give the impression that the pen isn't working...you might check that first....in all directions of movement. Heated (electrical resistance) tips might be a consideration, but the thermal paper prices are out of this world for obtaining and prices are the same of course. If you want to eventually take it email private, I do have a "junk box" assortment of other brand pens; that ~~~might~~~be mechanically adaptable if all else fails. It might involve cutting, solder or glue or other monstrocities of the original pen. If you have a accurate micrometer or vernier gauge that tells the outside and (rough) inside diameter of the pen; that "might" help. Chances are probably poor for a match; and it may involve you "adapting" a different brand or size. There is zero guarantee of my junk; they may be worn out also, or dried ink clogged; I've not used such for many years...it can be extremely frustrating to fuss with and get a "good" one. Meredith Lamb On Sat, Oct 24, 2009 at 1:56 PM, James Allen wrote: > Does anyone have or know of a place where I can obtain a replacement ink > dispensing writing stylus for a Teledyne-Geotech Helicorder? > Thanks > James Allen > > > >
James,
=A0
Perhaps Geotech might have such as Al Hrubetz suggests...but being as = ink stylus writing went out
long ago...one may have to resort to other (surplus...read: junk or un= known condition substitutes) brands.
The tips of worn pens usually gets worn out or abrasively flattened to= where the ink flow smears all over
the place; rather than flow evenly and write with little snagging &quo= t;sharpened" pen tip effect...as you likely already know.=A0 I've = never figured out how to "round out" or "smooth the outside = and inside" of the=A0writing tips to effectively, re-use such.
=A0
Sometimes....the pen tip isn't exactly flat to the writing drum su= rface (the prior tube gets bent up, down
or sideways...and this condition will give the impression that the pen= isn't working...you might check
that first....in all directions of movement.
=A0
Heated (electrical resistance) tips might be a consideration, but the = thermal paper prices are out of this
world for obtaining and prices are the same of course.
=A0
If you want to eventually take it email private, I do have a "jun= k box" assortment of other brand pens; that ~~~might~~~be mechanically= adaptable if all else fails.=A0 It might involve cutting, solder or glue o= r other
monstrocities of the original pen.=A0 If you have a accurate micromete= r or vernier gauge that tells the outside and (rough) inside diameter of th= e pen;=A0that "might" help.=A0 Chances are probably poor for a ma= tch; and it may involve you "adapting" a different brand or size.= =A0 There is zero guarantee of my junk; they may be worn out also, or dried= ink clogged; I've not used such for many years...it can be=A0extremely= frustrating to fuss with and get a "good" one.
=A0
Meredith Lamb
=A0=A0=A0

On Sat, Oct 24, 2009 at 1:56 PM, James Allen <jcallen1@verizon= ..net> wrote:
Does anyone have or know of a place wh= ere I can obtain a replacement ink dispensing writing stylus for a Teledyne= -Geotech Helicorder?
Thanks
James Allen
=A0
Subject: Re: TELEDYNE-GEOTECH HELICORDER From: "James Allen" jcallen1@........... Date: Sat, 24 Oct 2009 15:03:12 -0700 Thanks Al and Meredith regarding sourcing ink writing stylus for = helicorder. I guess I will stick with the thermal stylus that is on the = unit for the time being and contact Geotech and see if I can afford an = exact replacement. James Allen ----- Original Message -----=20 From: meredith lamb=20 To: psn-l@................. Sent: Saturday, October 24, 2009 2:38 PM Subject: Re: TELEDYNE-GEOTECH HELICORDER James, Perhaps Geotech might have such as Al Hrubetz suggests...but being as = ink stylus writing went out long ago...one may have to resort to other (surplus...read: junk or = unknown condition substitutes) brands. The tips of worn pens usually gets worn out or abrasively flattened to = where the ink flow smears all over the place; rather than flow evenly and write with little snagging = "sharpened" pen tip effect...as you likely already know. I've never = figured out how to "round out" or "smooth the outside and inside" of the = writing tips to effectively, re-use such. Sometimes....the pen tip isn't exactly flat to the writing drum = surface (the prior tube gets bent up, down or sideways...and this condition will give the impression that the pen = isn't working...you might check that first....in all directions of movement. Heated (electrical resistance) tips might be a consideration, but the = thermal paper prices are out of this world for obtaining and prices are the same of course. If you want to eventually take it email private, I do have a "junk = box" assortment of other brand pens; that ~~~might~~~be mechanically = adaptable if all else fails. It might involve cutting, solder or glue = or other monstrocities of the original pen. If you have a accurate micrometer = or vernier gauge that tells the outside and (rough) inside diameter of = the pen; that "might" help. Chances are probably poor for a match; and = it may involve you "adapting" a different brand or size. There is zero = guarantee of my junk; they may be worn out also, or dried ink clogged; = I've not used such for many years...it can be extremely frustrating to = fuss with and get a "good" one. Meredith Lamb =20 On Sat, Oct 24, 2009 at 1:56 PM, James Allen = wrote: Does anyone have or know of a place where I can obtain a replacement = ink dispensing writing stylus for a Teledyne-Geotech Helicorder? Thanks James Allen
Thanks Al and Meredith regarding = sourcing ink=20 writing stylus for helicorder.  I guess I will stick with the = thermal=20 stylus that is on the unit for the time being and contact Geotech and = see if I=20 can afford an exact replacement.
James Allen
----- Original Message -----
From:=20 meredith lamb
Sent: Saturday, October 24, = 2009 2:38=20 PM
Subject: Re: TELEDYNE-GEOTECH=20 HELICORDER

James,
 
Perhaps Geotech might have such as Al Hrubetz suggests...but = being as ink=20 stylus writing went out
long ago...one may have to resort to other (surplus...read: junk = or=20 unknown condition substitutes) brands.
The tips of worn pens usually gets worn out or abrasively = flattened to=20 where the ink flow smears all over
the place; rather than flow evenly and write with little snagging = "sharpened" pen tip effect...as you likely already know.  I've = never=20 figured out how to "round out" or "smooth the outside and inside" of=20 the writing tips to effectively, re-use such.
 
Sometimes....the pen tip isn't exactly flat to the writing drum = surface=20 (the prior tube gets bent up, down
or sideways...and this condition will give the impression that = the pen=20 isn't working...you might check
that first....in all directions of movement.
 
Heated (electrical resistance) tips might be a consideration, but = the=20 thermal paper prices are out of this
world for obtaining and prices are the same of course.
 
If you want to eventually take it email private, I do have a = "junk box"=20 assortment of other brand pens; that ~~~might~~~be mechanically = adaptable if=20 all else fails.  It might involve cutting, solder or glue or = other
monstrocities of the original pen.  If you have a accurate=20 micrometer or vernier gauge that tells the outside and (rough) inside = diameter=20 of the pen; that "might" help.  Chances are probably poor = for a=20 match; and it may involve you "adapting" a different brand or = size. =20 There is zero guarantee of my junk; they may be worn out also, or = dried ink=20 clogged; I've not used such for many years...it can be extremely=20 frustrating to fuss with and get a "good" one.
 
Meredith Lamb
   

On Sat, Oct 24, 2009 at 1:56 PM, James Allen = <jcallen1@...........> = wrote:
Does anyone have or know of a place = where I can=20 obtain a replacement ink dispensing writing stylus for a = Teledyne-Geotech=20 Helicorder?
Thanks
James Allen
 
Subject: Re: TELEDYNE-GEOTECH HELICORDER From: meredith lamb paleoartifact@......... Date: Sat, 24 Oct 2009 17:08:35 -0600 Hi James, I do know that even ~ 10 years ago; that even the USGS had great difficulties obtaining the thermal pens (because of the high Geotech price they wanted or unavailablility?); they then resorted to their own "homebrew" versions. I don't know the specific resistance wire they used; but a clue could be found by measuring your present thermal wire, in relation to the power source you have and doing some research. They literally heat unwrapped or cut off the old wire, and rewrapped welded/soldered the new resistance wire on the pen shaft/boom insulators...it was delicate, wire expensive and time and tool intensive stuff to do. The same surplus junk possiblity applies...I've some (? brand) thermal pens....if all else fails...they are a lot more long term reliable and easier to maintain. Good luck; in the best sense/meaning. Alas...my surplus guarantee is....10 foot travel/shipping time or 10 seconds whichever comes first...humor. I'am not in the surplus or commercial selling business. Take care, Meredith Lamb On Sat, Oct 24, 2009 at 4:03 PM, James Allen wrote: > Thanks Al and Meredith regarding sourcing ink writing stylus for > helicorder. I guess I will stick with the thermal stylus that is on the > unit for the time being and contact Geotech and see if I can afford an exact > replacement. > James Allen > > > >
Hi James,
=A0
I do know that even ~ 10 years ago; that even the USGS had great diffi= culties obtaining the thermal pens (because of the high Geotech price=A0the= y wanted=A0or unavailablility?); they then resorted to their own "home= brew" versions.=A0 I don't know the specific resistance wire they = used; but a clue could be found by measuring your present thermal wire, in = relation to the power source you have and doing some research.
They literally heat unwrapped or cut off the old wire, and rewrapped w= elded/soldered the new resistance wire on the pen shaft/boom insulators...i= t was delicate, wire expensive=A0and time and tool intensive stuff to do.
=A0
The same surplus junk possiblity applies...I've some (? brand) the= rmal pens....if all else fails...they are
a lot more long term reliable and easier to maintain.=A0Good luck; in = the best sense/meaning.=A0=A0Alas...my surplus guarantee is....10 foot trav= el/shipping time or 10 seconds whichever comes first...humor.=A0 I'am n= ot
in the surplus or commercial selling business.
=A0
Take care,=A0Meredith Lamb=A0
=A0
=A0
=A0
=A0=A0=A0

On Sat, Oct 24, 2009 at 4:03 PM, James Allen <jcallen1@...........> wrote:
Thanks Al and Meredith regarding sourc= ing ink writing stylus for helicorder.=A0 I guess I will stick with the the= rmal stylus that is on the unit for the time being and contact Geotech and = see if I can afford an exact replacement.
James Allen
=A0
Subject: Earthquake Lists From: "Kay Wyatt" kwyatt@............. Date: Sat, 24 Oct 2009 16:17:30 -0700 To my earthquake friends... I wonder if anybody is interested in creating a common PSN earthquake = list. There is a wonderful tool offered by Google that could be used = called "Google Docs". It allows a group of people access to documents = of common interest. =20 I've set up an example account which you can take a peek at if you want. = =20 WEBSITE: http://docs.google.com ACCOUNT: kay@............. PASSWORD: seismograph Note that only one person can enter this account at a time so be = patient. Now, there is not much value to a group document that only one person = can access at a time. HOWEVER, if anybody has a google account, the = document can be SHARED with that account. What is most amazing is that you can have any number of people editing = the document at the same time, AND, you can actually see others adding = information in real time by watching their keystrokes. I'm not sure who = designed this product but it is quite amazing. So, we could have a master earthquake list under a PSN account. Then = the PSN master can "invite" anybody on the PSN network to share the = list. That person, then, would set up their own Google account and the = spreadsheet would show up in their Google docs list. In this way, we can share valuable information easily. The example spreadsheet that I loaded into Google Docs is not set in = stone. It is just an example of what might be. The entries in the = spreadsheet are: DATE YY/MM/DD=20 TIME(GMT)=20 HR:MN:SS=20 LAT (deg)=20 LON (deg)=20 DEPTH (km) USGS Magnitude (Mw)=20 Earthquake Location=20 My Station Name=20 P-WAVE ARRIVAL TIME(GMT) HR:MN:SS=20 S-WAVE ARRIVAL TIME(GMT) HR:MN:SS=20 Distance to earthquake (deg)=20 Comments The last five entries are specific to your station only. The rest are = specific to the earthquake and common to all stations. You can do all the usually spreadsheet things like sort, etc. You can = also export the data into an Excel spreadsheet local to your computer = for graphing, etc. You can sign up for a Google account at=20 https://www.google.com/accounts It would be nice to set up a dialog to see how many folks might be = interested. Kay Wyatt
To my earthquake friends...
 
I wonder if anybody is interested in creating a = common PSN=20 earthquake list.  There is a wonderful tool offered by Google that = could be=20 used called "Google Docs".  It allows a group of people access to = documents=20 of common interest. 
 
I've set up an example account which you can = take a peek=20 at if you want. 
 
WEBSITE:    http://docs.google.com
ACCOUNT:    kay@.............
PASSWORD:    = seismograph
 
Note that only one person can enter this account = at a time=20 so be patient.
 
Now, there is not much value to a group document = that only=20 one person can access at a time.  HOWEVER, if anybody has a google = account,=20 the document can be SHARED with that account.
 
What is most amazing is that you can have any = number of=20 people editing the document at the same time, AND, you can actually see = others=20 adding information in real time by watching their keystrokes.  I'm = not sure=20 who designed this product but it is quite amazing.
 
So, we could have a master earthquake list under = a PSN=20 account.  Then the PSN master can "invite" anybody on the PSN = network to=20 share the list.  That person, then, would set up their own Google = account=20 and the spreadsheet would show up in their Google docs = list.
 
In this way, we can share valuable information=20 easily.
 
The example spreadsheet that I loaded into = Google Docs is=20 not set in stone.  It is just an example of what might be.  = The=20 entries in the spreadsheet are:
DATE YY/MM/DD 
TIME(GMT)
HR:MN:SS 
LAT (deg) 
LON (deg) 
DEPTH (km)
USGS Magnitude (Mw) 
Earthquake Location 
My Station Name 
P-WAVE ARRIVAL TIME(GMT) = HR:MN:SS 
S-WAVE ARRIVAL TIME(GMT) = HR:MN:SS 
Distance to earthquake = (deg) 
Comments
The last five entries are specific to = your station=20 only.  The rest are specific to the earthquake and common to all=20 stations.
 
You can do all the usually spreadsheet = things like=20 sort, etc.  You can also export the data into an Excel spreadsheet = local to=20 your computer for graphing, etc.
 
You can sign up for a Google account at =
https://www.google.com/accounts<= /A>
 
It would be nice to set up a dialog to see how = many folks=20 might be interested.
 
Kay Wyatt
 
 

Subject: Re: TELEDYNE-GEOTECH HELICORDER From: ChrisAtUpw@....... Date: Sat, 24 Oct 2009 21:54:16 EDT In a message dated 24/10/2009 22:44:00 GMT Daylight Time, paleoartifact@......... writes: Perhaps Geotech might have such as Al Hrubetz suggests...but being as ink stylus writing went out long ago...one may have to resort to other (surplus...read: junk or unknown condition substitutes) brands. Hi James, It's just an idea, but I can still buy ink drawing pens for technical drawing. They have plastic push on ink cartridges which can be refilled and the ink is available in 250 ml and 23 ml bottles. The ones which I am familiar with are UNO and Rotring. The Rotring Isograph nibs are available separately from 0.1 to 1.0 mm. Note that you can also buy fine stainless steel tube in a wide range of sizes. I use fine piano wire for cleaning blocked pens with the special cleaning solution. Hot Fairy washing up liquid also breaks down the ink quite well. Note that hot wires are usually spot welded on. I would expect the wire to be Nichrome. Regards, Chris Chapman .
In a message dated 24/10/2009 22:44:00 GMT Daylight Time,=20 paleoartifact@......... writes:
Perhaps Geotech might have such as Al Hrubetz suggests...but being= as ink=20 stylus writing went out long ago...one may have to resort to other=20 (surplus...read: junk or unknown condition substitutes)=20 brands.
Hi James,
 
    It's just an idea, but I can still buy ink dr= awing=20 pens for technical drawing. They have plastic push on ink cartridges which= can=20 be refilled and the ink is available in 250 ml and 23 ml bottles. The ones= which=20 I am familiar with are UNO and Rotring. The Rotring Isograph nibs are avai= lable=20 separately from 0.1 to 1.0 mm.
    Note that you can also buy fine stainless ste= el=20 tube in a wide range of sizes. I use fine piano wire for cleaning blocked= pens=20 with the special cleaning solution. Hot Fairy washing up liquid also break= s down=20 the ink quite well.
    Note that hot wires are usually spot welded= on. I=20 would expect the wire to be Nichrome.
 
    Regards,
 
    Chris Chapman
    .  
Subject: Re: Earthquake Lists From: Dave Nelson dave.nelson@............... Date: Sun, 25 Oct 2009 13:49:41 +1100
Hi Kay,
             Do you realise we already have a common PSN quake list ??
  Larry Cochrane has been running one since the early days and already has many
 1000's of events listed  recent and in archives from the PSN members

people are able to download a gif image of some ones event for a quick look or download the data to load into their winquake to do their own filtering etc in that event file.
see....   http://psn.quake.net/cgi-dos/event.exe

cheers
Dave N
Sydney
Australia





At 04:17 PM 10/24/2009 -0700, you wrote:
To my earthquake friends...
 
I wonder if anybody is interested in creating a common PSN earthquake list.  There is a wonderful tool offered by Google that could be used called "Google Docs".  It allows a group of people access to documents of common interest. 
 
I've set up an example account which you can take a peek at if you want. 
 
WEBSITE:    http://docs.google.com
ACCOUNT:    kay@.............
PASSWORD:    seismograph
 
Note that only one person can enter this account at a time so be patient.
 
Now, there is not much value to a group document that only one person can access at a time.  HOWEVER, if anybody has a google account, the document can be SHARED with that account.
 
What is most amazing is that you can have any number of people editing the document at the same time, AND, you can actually see others adding information in real time by watching their keystrokes.  I'm not sure who designed this product but it is quite amazing.
 
So, we could have a master earthquake list under a PSN account.  Then the PSN master can "invite" anybody on the PSN network to share the list.  That person, then, would set up their own Google account and the spreadsheet would show up in their Google docs list.
 
In this way, we can share valuable information easily.
 
The example spreadsheet that I loaded into Google Docs is not set in stone.  It is just an example of what might be.  The entries in the spreadsheet are:
DATE YY/MM/DD
TIME(GMT)
HR:MN:SS
LAT (deg)
LON (deg)
DEPTH (km)
USGS Magnitude (Mw)
Earthquake Location
My Station Name
P-WAVE ARRIVAL TIME(GMT) HR:MN:SS
S-WAVE ARRIVAL TIME(GMT) HR:MN:SS
Distance to earthquake (deg)
Comments

The last five entries are specific to your station only.  The rest are specific to the earthquake and common to all stations.
 
You can do all the usually spreadsheet things like sort, etc.  You can also export the data into an Excel spreadsheet local to your computer for graphing, etc.
 
You can sign up for a Google account at
https://www.google.com/accounts
 
It would be nice to set up a dialog to see how many folks might be interested.
 
Kay Wyatt
 
 


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Subject: Re: TELEDYNE-GEOTECH HELICORDER From: "James Allen" jcallen1@........... Date: Sat, 24 Oct 2009 20:09:10 -0700 I think that Chris has a great idea for using ink on a Helicorder. I = appreciate it and will experiment with this approach. James Allen ----- Original Message -----=20 From: ChrisAtUpw@.......... To: psn-l@................. Sent: Saturday, October 24, 2009 6:54 PM Subject: Re: TELEDYNE-GEOTECH HELICORDER In a message dated 24/10/2009 22:44:00 GMT Daylight Time, = paleoartifact@......... writes: Perhaps Geotech might have such as Al Hrubetz suggests...but being = as ink stylus writing went out long ago...one may have to resort to = other (surplus...read: junk or unknown condition substitutes) brands. Hi James, It's just an idea, but I can still buy ink drawing pens for = technical drawing. They have plastic push on ink cartridges which can be = refilled and the ink is available in 250 ml and 23 ml bottles. The ones = which I am familiar with are UNO and Rotring. The Rotring Isograph nibs = are available separately from 0.1 to 1.0 mm.=20 Note that you can also buy fine stainless steel tube in a wide = range of sizes. I use fine piano wire for cleaning blocked pens with the = special cleaning solution. Hot Fairy washing up liquid also breaks down = the ink quite well. Note that hot wires are usually spot welded on. I would expect the = wire to be Nichrome. Regards, Chris Chapman .
I think that Chris has a great idea for using ink on a=20 Helicorder.   I appreciate it and will experiment with this=20 approach.
James Allen
----- Original Message -----
From:=20 ChrisAtUpw@.......
Sent: Saturday, October 24, = 2009 6:54=20 PM
Subject: Re: TELEDYNE-GEOTECH=20 HELICORDER

In a message dated 24/10/2009 22:44:00 GMT Daylight Time, paleoartifact@.........=20 writes:
Perhaps Geotech might have such as Al Hrubetz suggests...but = being as=20 ink stylus writing went out long ago...one may have to resort to = other=20 (surplus...read: junk or unknown condition substitutes)=20 brands.
Hi James,
 
    It's just an idea, but I can still buy = ink=20 drawing pens for technical drawing. They have plastic push on ink = cartridges=20 which can be refilled and the ink is available in 250 ml and 23 ml = bottles.=20 The ones which I am familiar with are UNO and Rotring. The Rotring = Isograph=20 nibs are available separately from 0.1 to 1.0 mm.
    Note that you can also buy fine stainless = steel=20 tube in a wide range of sizes. I use fine piano wire for cleaning = blocked pens=20 with the special cleaning solution. Hot Fairy washing up liquid also = breaks=20 down the ink quite well.
    Note that hot wires are usually spot = welded on. I=20 would expect the wire to be Nichrome.
 
    Regards,
 
    Chris Chapman
    . =  
Subject: Re: TELEDYNE-GEOTECH HELICORDER From: "James Allen" jcallen1@........... Date: Sat, 24 Oct 2009 20:31:45 -0700 For anyone else facing using ink in an old Teledyne-Geotech Helicorder, = I was just informed that one might use the very small felt tip ink pens = used on hygrothermographs. I understand they come in blue or red ink = color, last a long time and will just slip over the end of the = helicorder stylus with minor modification. James Allen ----- Original Message -----=20 From: ChrisAtUpw@.......... To: psn-l@................. Sent: Saturday, October 24, 2009 6:54 PM Subject: Re: TELEDYNE-GEOTECH HELICORDER In a message dated 24/10/2009 22:44:00 GMT Daylight Time, = paleoartifact@......... writes: Perhaps Geotech might have such as Al Hrubetz suggests...but being = as ink stylus writing went out long ago...one may have to resort to = other (surplus...read: junk or unknown condition substitutes) brands. Hi James, It's just an idea, but I can still buy ink drawing pens for = technical drawing. They have plastic push on ink cartridges which can be = refilled and the ink is available in 250 ml and 23 ml bottles. The ones = which I am familiar with are UNO and Rotring. The Rotring Isograph nibs = are available separately from 0.1 to 1.0 mm.=20 Note that you can also buy fine stainless steel tube in a wide = range of sizes. I use fine piano wire for cleaning blocked pens with the = special cleaning solution. Hot Fairy washing up liquid also breaks down = the ink quite well. Note that hot wires are usually spot welded on. I would expect the = wire to be Nichrome. Regards, Chris Chapman .
For anyone else facing using ink in an old Teledyne-Geotech = Helicorder, I=20 was just informed that one might use the very small felt tip ink pens = used on=20 hygrothermographs.  I understand they come in blue or red ink = color, last a=20 long time and will just slip over the end of the helicorder stylus with = minor=20 modification.
James Allen
----- Original Message -----
From:=20 ChrisAtUpw@.......
Sent: Saturday, October 24, = 2009 6:54=20 PM
Subject: Re: TELEDYNE-GEOTECH=20 HELICORDER

In a message dated 24/10/2009 22:44:00 GMT Daylight Time, paleoartifact@.........=20 writes:
Perhaps Geotech might have such as Al Hrubetz suggests...but = being as=20 ink stylus writing went out long ago...one may have to resort to = other=20 (surplus...read: junk or unknown condition substitutes)=20 brands.
Hi James,
 
    It's just an idea, but I can still buy = ink=20 drawing pens for technical drawing. They have plastic push on ink = cartridges=20 which can be refilled and the ink is available in 250 ml and 23 ml = bottles.=20 The ones which I am familiar with are UNO and Rotring. The Rotring = Isograph=20 nibs are available separately from 0.1 to 1.0 mm.
    Note that you can also buy fine stainless = steel=20 tube in a wide range of sizes. I use fine piano wire for cleaning = blocked pens=20 with the special cleaning solution. Hot Fairy washing up liquid also = breaks=20 down the ink quite well.
    Note that hot wires are usually spot = welded on. I=20 would expect the wire to be Nichrome.
 
    Regards,
 
    Chris Chapman
    . =  
Subject: RE: TELEDYNE-GEOTECH HELICORDER From: "Stephen Hammond" shammon1@............. Date: Sat, 24 Oct 2009 20:37:31 -0700 For some time some PSN members were using hypodermic needs to build ink pens. You simply grind the point off and have a precession tip that can then be connected to the reservoir using a capillary feed tube. We learned the process from Howard who used this design back in the first Bay area seismic station way before our time in the 40's. I ran two drum recorders back around 1990 and Jan Froom currently has a display station at Bonfante Gardens in Gilroy CA that has a permanent display he put together for them also using this design. Regards, Steve Hammond PSN Aptos, CA From: psn-l-request@.............. [mailto:psn-l-request@............... On Behalf Of James Allen Sent: Saturday, October 24, 2009 8:09 PM To: psn-l@.............. Subject: Re: TELEDYNE-GEOTECH HELICORDER I think that Chris has a great idea for using ink on a Helicorder. I appreciate it and will experiment with this approach. James Allen ----- Original Message ----- From: ChrisAtUpw@....... To: psn-l@.............. Sent: Saturday, October 24, 2009 6:54 PM Subject: Re: TELEDYNE-GEOTECH HELICORDER In a message dated 24/10/2009 22:44:00 GMT Daylight Time, paleoartifact@......... writes: Perhaps Geotech might have such as Al Hrubetz suggests...but being as ink stylus writing went out long ago...one may have to resort to other (surplus...read: junk or unknown condition substitutes) brands. Hi James, It's just an idea, but I can still buy ink drawing pens for technical drawing. They have plastic push on ink cartridges which can be refilled and the ink is available in 250 ml and 23 ml bottles. The ones which I am familiar with are UNO and Rotring. The Rotring Isograph nibs are available separately from 0.1 to 1.0 mm. Note that you can also buy fine stainless steel tube in a wide range of sizes. I use fine piano wire for cleaning blocked pens with the special cleaning solution. Hot Fairy washing up liquid also breaks down the ink quite well. Note that hot wires are usually spot welded on. I would expect the wire to be Nichrome. Regards, Chris Chapman .

For some time some PSN members were using hypodermic = needs to build ink pens. You simply grind the point off and have a precession tip = that  can then be connected to the reservoir using a capillary feed tube. We = learned the process from Howard who used this design back in the first Bay area = seismic station way before our time in the 40’s. I ran two drum recorders = back around 1990 and Jan Froom currently has a display station at Bonfante = Gardens  in Gilroy CA that has a permanent display he put together for them also = using this design.

Regards, Steve Hammond PSN Aptos, = CA

 

 

From:= psn-l-request@.............. [mailto:psn-l-request@............... On = Behalf Of James Allen
Sent: Saturday, October 24, 2009 8:09 PM
To: psn-l@..............
Subject: Re: TELEDYNE-GEOTECH HELICORDER

 

I think that Chris has a great idea for using ink on a Helicorder.   I appreciate it and will experiment with this = approach.

James Allen

----- Original Message -----

Sent: Saturday, October 24, 2009 6:54 PM

Subject: Re: TELEDYNE-GEOTECH HELICORDER

 

In a message dated 24/10/2009 22:44:00 GMT Daylight Time, = paleoartifact@......... = writes:

Perhaps Geotech might have such as Al Hrubetz = suggests...but being as ink stylus writing went out long ago...one may have to resort to = other (surplus...read: junk or unknown condition substitutes) = brands.

Hi James,

 

    It's just an idea, but I can still = buy ink drawing pens for technical drawing. They have plastic push on ink = cartridges which can be refilled and the ink is available in 250 ml and 23 ml = bottles. The ones which I am familiar with are UNO and Rotring. The Rotring Isograph = nibs are available separately from 0.1 to 1.0 mm.

    Note that you can also buy fine = stainless steel tube in a wide range of sizes. I use fine piano wire for cleaning = blocked pens with the special cleaning solution. Hot Fairy washing up liquid = also breaks down the ink quite well.

    Note that hot wires are usually = spot welded on. I would expect the wire to be Nichrome.

 

    Regards,

 

    Chris Chapman

    .  

Subject: RE: TELEDYNE-GEOTECH HELICORDER From: "Stephen Hammond" shammon1@............. Date: Sat, 24 Oct 2009 20:41:40 -0700 There is a typo. Not needs try needle. Steve From: psn-l-request@.............. [mailto:psn-l-request@............... On Behalf Of Stephen Hammond Sent: Saturday, October 24, 2009 8:38 PM To: psn-l@.............. Subject: RE: TELEDYNE-GEOTECH HELICORDER For some time some PSN members were using hypodermic needs to build ink pens. You simply grind the point off and have a precession tip that can then be connected to the reservoir using a capillary feed tube. We learned the process from Howard who used this design back in the first Bay area seismic station way before our time in the 40's. I ran two drum recorders back around 1990 and Jan Froom currently has a display station at Bonfante Gardens in Gilroy CA that has a permanent display he put together for them also using this design. Regards, Steve Hammond PSN Aptos, CA From: psn-l-request@.............. [mailto:psn-l-request@............... On Behalf Of James Allen Sent: Saturday, October 24, 2009 8:09 PM To: psn-l@.............. Subject: Re: TELEDYNE-GEOTECH HELICORDER I think that Chris has a great idea for using ink on a Helicorder. I appreciate it and will experiment with this approach. James Allen ----- Original Message ----- From: ChrisAtUpw@....... To: psn-l@.............. Sent: Saturday, October 24, 2009 6:54 PM Subject: Re: TELEDYNE-GEOTECH HELICORDER In a message dated 24/10/2009 22:44:00 GMT Daylight Time, paleoartifact@......... writes: Perhaps Geotech might have such as Al Hrubetz suggests...but being as ink stylus writing went out long ago...one may have to resort to other (surplus...read: junk or unknown condition substitutes) brands. Hi James, It's just an idea, but I can still buy ink drawing pens for technical drawing. They have plastic push on ink cartridges which can be refilled and the ink is available in 250 ml and 23 ml bottles. The ones which I am familiar with are UNO and Rotring. The Rotring Isograph nibs are available separately from 0.1 to 1.0 mm. Note that you can also buy fine stainless steel tube in a wide range of sizes. I use fine piano wire for cleaning blocked pens with the special cleaning solution. Hot Fairy washing up liquid also breaks down the ink quite well. Note that hot wires are usually spot welded on. I would expect the wire to be Nichrome. Regards, Chris Chapman .

There is a typo. Not needs try needle… = Steve

 

From:= psn-l-request@.............. [mailto:psn-l-request@............... On = Behalf Of Stephen Hammond
Sent: Saturday, October 24, 2009 8:38 PM
To: psn-l@..............
Subject: RE: TELEDYNE-GEOTECH HELICORDER

 

For some time some PSN members were using hypodermic = needs to build ink pens. You simply grind the point off and have a precession tip = that  can then be connected to the reservoir using a capillary feed = tube. We learned the process from Howard who used this design back in the first = Bay area seismic station way before our time in the 40’s. I ran two drum = recorders back around 1990 and Jan Froom currently has a display station at Bonfante = Gardens  in Gilroy CA that has a permanent display he put together for them = also using this design.

Regards, Steve Hammond PSN Aptos, = CA

 

 

From:= psn-l-request@.............. [mailto:psn-l-request@............... On = Behalf Of James Allen
Sent: Saturday, October 24, 2009 8:09 PM
To: psn-l@..............
Subject: Re: TELEDYNE-GEOTECH HELICORDER

 

I think that Chris has a great idea for using ink on a Helicorder.   I appreciate it and will experiment with this = approach.

James Allen

----- Original Message -----

Sent: Saturday, October 24, 2009 6:54 PM

Subject: Re: TELEDYNE-GEOTECH HELICORDER

 

In a message dated 24/10/2009 22:44:00 GMT Daylight Time, = paleoartifact@......... = writes:

Perhaps Geotech might have such as Al Hrubetz = suggests...but being as ink stylus writing went out long ago...one may have to resort to = other (surplus...read: junk or unknown condition substitutes) brands.

Hi James,

 

    It's just an idea, but I can still = buy ink drawing pens for technical drawing. They have plastic push on ink = cartridges which can be refilled and the ink is available in 250 ml and 23 ml = bottles. The ones which I am familiar with are UNO and Rotring. The Rotring Isograph = nibs are available separately from 0.1 to 1.0 mm.

    Note that you can also buy fine = stainless steel tube in a wide range of sizes. I use fine piano wire for cleaning = blocked pens with the special cleaning solution. Hot Fairy washing up liquid = also breaks down the ink quite well.

    Note that hot wires are usually = spot welded on. I would expect the wire to be Nichrome.

 

    Regards,

 

    Chris Chapman

    .  

Subject: Re: TELEDYNE-GEOTECH HELICORDER From: "James Allen" jcallen1@........... Date: Sat, 24 Oct 2009 21:45:48 -0700 Steve Hammond Is there need for a special reservoir to insert the capillary tubing = into or will the ink start flowing by the action of the pen on the chart = paper? Thanks James Allen ----- Original Message -----=20 From: Stephen Hammond=20 To: psn-l@................. Sent: Saturday, October 24, 2009 8:41 PM Subject: RE: TELEDYNE-GEOTECH HELICORDER There is a typo. Not needs try needle. Steve =20 From: psn-l-request@.............. = [mailto:psn-l-request@............... On Behalf Of Stephen Hammond Sent: Saturday, October 24, 2009 8:38 PM To: psn-l@.............. Subject: RE: TELEDYNE-GEOTECH HELICORDER =20 For some time some PSN members were using hypodermic needs to build = ink pens. You simply grind the point off and have a precession tip that = can then be connected to the reservoir using a capillary feed tube. We = learned the process from Howard who used this design back in the first = Bay area seismic station way before our time in the 40's. I ran two drum = recorders back around 1990 and Jan Froom currently has a display station = at Bonfante Gardens in Gilroy CA that has a permanent display he put = together for them also using this design.=20 Regards, Steve Hammond PSN Aptos, CA =20 =20 From: psn-l-request@.............. = [mailto:psn-l-request@............... On Behalf Of James Allen Sent: Saturday, October 24, 2009 8:09 PM To: psn-l@.............. Subject: Re: TELEDYNE-GEOTECH HELICORDER =20 I think that Chris has a great idea for using ink on a Helicorder. I = appreciate it and will experiment with this approach. James Allen ----- Original Message -----=20 From: ChrisAtUpw@.......... To: psn-l@................. Sent: Saturday, October 24, 2009 6:54 PM Subject: Re: TELEDYNE-GEOTECH HELICORDER =20 In a message dated 24/10/2009 22:44:00 GMT Daylight Time, = paleoartifact@......... writes: Perhaps Geotech might have such as Al Hrubetz suggests...but being = as ink stylus writing went out long ago...one may have to resort to = other (surplus...read: junk or unknown condition substitutes) brands. Hi James, =20 It's just an idea, but I can still buy ink drawing pens for = technical drawing. They have plastic push on ink cartridges which can be = refilled and the ink is available in 250 ml and 23 ml bottles. The ones = which I am familiar with are UNO and Rotring. The Rotring Isograph nibs = are available separately from 0.1 to 1.0 mm.=20 Note that you can also buy fine stainless steel tube in a wide = range of sizes. I use fine piano wire for cleaning blocked pens with the = special cleaning solution. Hot Fairy washing up liquid also breaks down = the ink quite well. Note that hot wires are usually spot welded on. I would expect = the wire to be Nichrome. =20 Regards, =20 Chris Chapman . =20
Steve Hammond
Is there need for a special reservoir = to insert the=20 capillary tubing into or will the ink start flowing by the action of the = pen on=20 the chart paper?
Thanks
James Allen
----- Original Message -----
From:=20 Stephen=20 Hammond
Sent: Saturday, October 24, = 2009 8:41=20 PM
Subject: RE: TELEDYNE-GEOTECH=20 HELICORDER

There=20 is a typo. Not needs try needle=85 Steve

 

From: psn-l-request@............... =20 [mailto:psn-l-request@............... On Behalf Of Stephen=20 Hammond
Sent: Saturday, October 24, 2009 8:38 = PM
To: psn-l@..............
Subje= ct:=20 RE: TELEDYNE-GEOTECH HELICORDER

 

For=20 some time some PSN members were using hypodermic needs to build ink = pens. You=20 simply grind the point off and have a precession tip that  can = then be=20 connected to the reservoir using a capillary feed tube. We learned the = process=20 from Howard who used this design back in the first Bay area seismic = station=20 way before our time in the 40=92s. I ran two drum recorders back = around 1990 and=20 Jan Froom currently has a display station at Bonfante Gardens  in = Gilroy=20 CA that has a permanent display he put together for them also using = this=20 design.

Regards,=20 Steve Hammond PSN Aptos, CA

 

 

From:=20 psn-l-request@.............. [mailto:psn-l-request@............... = On=20 Behalf Of James Allen
Sent: Saturday, October 24, 2009 = 8:09=20 PM
To: psn-l@..............
Subject: Re: = TELEDYNE-GEOTECH=20 HELICORDER

 

I=20 think that Chris has a great idea for using ink on a = Helicorder.   I=20 appreciate it and will experiment with this=20 approach.

James=20 Allen

-----=20 Original Message -----

From: ChrisAtUpw@.......=20

To: psn-l@..............=20

Sent:=20 Saturday, October 24, 2009 6:54 PM

Subject:=20 Re: TELEDYNE-GEOTECH HELICORDER

 

In=20 a message dated 24/10/2009 22:44:00 GMT Daylight Time, paleoartifact@.........=20 writes:

Perhaps=20 Geotech might have such as Al Hrubetz suggests...but being as ink = stylus=20 writing went out long ago...one may have to resort to other=20 (surplus...read: junk or unknown condition substitutes)=20 brands.

Hi=20 James,

 

    It's=20 just an idea, but I can still buy ink drawing pens for technical = drawing.=20 They have plastic push on ink cartridges which can be refilled and = the ink=20 is available in 250 ml and 23 ml bottles. The ones which I am = familiar with=20 are UNO and Rotring. The Rotring Isograph nibs are available = separately from=20 0.1 to 1.0 mm.

    Note=20 that you can also buy fine stainless steel tube in a wide range of = sizes. I=20 use fine piano wire for cleaning blocked pens with the special = cleaning=20 solution. Hot Fairy washing up liquid also breaks down the ink quite = well.

    Note=20 that hot wires are usually spot welded on. I would expect the wire = to be=20 Nichrome.

 

    Regards,

 

    Chris=20 Chapman

    .=20 =  

= Subject: RE: TELEDYNE-GEOTECH HELICORDER From: "Stephen Hammond" shammon1@............. Date: Sun, 25 Oct 2009 00:13:36 -0700 Hi, the ink will flow if the reservoir fluid level is above the pen. The trick is to keep it from flowing too much. I used a wire clamp on the tubing to cut the flow down. Professional models used low pressure pumps and an fin valve. If I can suggest, search online for "chart pen ink" and you will find the Recorder Charts Pens Company in Newhall CA. 800-758-0740. While they do not list your unit they have a large selection of professional pens, ink and paper. It might be worth a trip to the website or even a call to see what they can offer in the way of a solution. Steve From: psn-l-request@.............. [mailto:psn-l-request@............... On Behalf Of James Allen Sent: Saturday, October 24, 2009 9:46 PM To: psn-l@.............. Subject: Re: TELEDYNE-GEOTECH HELICORDER Steve Hammond Is there need for a special reservoir to insert the capillary tubing into or will the ink start flowing by the action of the pen on the chart paper? Thanks James Allen ----- Original Message ----- From: Stephen Hammond To: psn-l@.............. Sent: Saturday, October 24, 2009 8:41 PM Subject: RE: TELEDYNE-GEOTECH HELICORDER There is a typo. Not needs try needle. Steve From: psn-l-request@.............. [mailto:psn-l-request@............... On Behalf Of Stephen Hammond Sent: Saturday, October 24, 2009 8:38 PM To: psn-l@.............. Subject: RE: TELEDYNE-GEOTECH HELICORDER For some time some PSN members were using hypodermic needs to build ink pens. You simply grind the point off and have a precession tip that can then be connected to the reservoir using a capillary feed tube. We learned the process from Howard who used this design back in the first Bay area seismic station way before our time in the 40's. I ran two drum recorders back around 1990 and Jan Froom currently has a display station at Bonfante Gardens in Gilroy CA that has a permanent display he put together for them also using this design. Regards, Steve Hammond PSN Aptos, CA From: psn-l-request@.............. [mailto:psn-l-request@............... On Behalf Of James Allen Sent: Saturday, October 24, 2009 8:09 PM To: psn-l@.............. Subject: Re: TELEDYNE-GEOTECH HELICORDER I think that Chris has a great idea for using ink on a Helicorder. I appreciate it and will experiment with this approach. James Allen ----- Original Message ----- From: ChrisAtUpw@....... To: psn-l@.............. Sent: Saturday, October 24, 2009 6:54 PM Subject: Re: TELEDYNE-GEOTECH HELICORDER In a message dated 24/10/2009 22:44:00 GMT Daylight Time, paleoartifact@......... writes: Perhaps Geotech might have such as Al Hrubetz suggests...but being as ink stylus writing went out long ago...one may have to resort to other (surplus...read: junk or unknown condition substitutes) brands. Hi James, It's just an idea, but I can still buy ink drawing pens for technical drawing. They have plastic push on ink cartridges which can be refilled and the ink is available in 250 ml and 23 ml bottles. The ones which I am familiar with are UNO and Rotring. The Rotring Isograph nibs are available separately from 0.1 to 1.0 mm. Note that you can also buy fine stainless steel tube in a wide range of sizes. I use fine piano wire for cleaning blocked pens with the special cleaning solution. Hot Fairy washing up liquid also breaks down the ink quite well. Note that hot wires are usually spot welded on. I would expect the wire to be Nichrome. Regards, Chris Chapman .

Hi, the ink will flow if the reservoir fluid level is = above the pen. The trick is to keep it from flowing too much. I used a wire clamp = on the tubing to cut the flow down. Professional models used low pressure pumps = and an fin valve. If I can suggest, search online for “chart pen = ink” and you will find the Recorder Charts Pens Company in Newhall CA. = 800-758-0740. While they do not list your unit they have a large selection of = professional pens, ink and paper. It might be worth a trip to the website or even a call to = see what they can offer in the way of a solution.

Steve

 

From:= psn-l-request@.............. [mailto:psn-l-request@............... On = Behalf Of James Allen
Sent: Saturday, October 24, 2009 9:46 PM
To: psn-l@..............
Subject: Re: TELEDYNE-GEOTECH HELICORDER

 

Steve Hammond

Is there need for a special reservoir to insert the capillary tubing into = or will the ink start flowing by the action of the pen on the chart = paper?

Thanks=

James Allen

----- Original Message -----

From: Stephen Hammond =

Sent:<= /b> Saturday, = October 24, 2009 8:41 PM

Subject: RE: = TELEDYNE-GEOTECH HELICORDER

 

There is a typo. Not needs try needle… = Steve

 

From:= psn-l-request@............... [mailto:psn-l-request@............... On Behalf Of Stephen = Hammond
Sent: Saturday, October 24, 2009 8:38 PM
To: psn-l@..............
Subject: RE: TELEDYNE-GEOTECH HELICORDER

 

For some time some PSN members were using hypodermic = needs to build ink pens. You simply grind the point off and have a precession tip = that  can then be connected to the reservoir using a capillary feed = tube. We learned the process from Howard who used this design back in the first = Bay area seismic station way before our time in the 40’s. I ran two drum = recorders back around 1990 and Jan Froom currently has a display station at = Bonfante Gardens  in Gilroy CA that has a permanent display he put together = for them also using this design.

Regards, Steve Hammond PSN Aptos, = CA

 

 

From:= psn-l-request@.............. [mailto:psn-l-request@............... On = Behalf Of James Allen
Sent: Saturday, October 24, 2009 8:09 PM
To: psn-l@..............
Subject: Re: TELEDYNE-GEOTECH HELICORDER

 

I think that Chris has a great idea for using ink on a Helicorder.   I appreciate it and will experiment with this = approach.

James Allen

----- Original Message -----

Sent: Saturday, October 24, 2009 6:54 PM

Subject: Re: TELEDYNE-GEOTECH HELICORDER

 

In a message dated 24/10/2009 22:44:00 GMT Daylight Time, = paleoartifact@......... = writes:

Perhaps Geotech might have such as Al Hrubetz = suggests...but being as ink stylus writing went out long ago...one may have to resort to = other (surplus...read: junk or unknown condition substitutes) = brands.

Hi James,

 

    It's just an idea, but I can still = buy ink drawing pens for technical drawing. They have plastic push on ink = cartridges which can be refilled and the ink is available in 250 ml and 23 ml = bottles. The ones which I am familiar with are UNO and Rotring. The Rotring Isograph = nibs are available separately from 0.1 to 1.0 mm.

    Note that you can also buy fine = stainless steel tube in a wide range of sizes. I use fine piano wire for cleaning = blocked pens with the special cleaning solution. Hot Fairy washing up liquid = also breaks down the ink quite well.

    Note that hot wires are usually = spot welded on. I would expect the wire to be Nichrome.

 

    Regards,

 

    Chris Chapman

    .  

Subject: Re: TELEDYNE-GEOTECH HELICORDER From: AHrubetz@....... Date: Sun, 25 Oct 2009 09:57:05 EDT James, As of June, 2008, Geotech Instruments price for a Replacement heat writing stylus Model 38548 was $75.00. Five hundred sheets of heat writing paper was $255.00 Al In a message dated 10/24/2009 5:03:41 P.M. Central Daylight Time, jcallen1@........... writes: Thanks Al and Meredith regarding sourcing ink writing stylus for helicorder. I guess I will stick with the thermal stylus that is on the unit for the time being and contact Geotech and see if I can afford an exact replacement. James Allen ----- Original Message ----- From: _meredith lamb_ (mailto:paleoartifact@.......... To: _psn-l@............... (mailto:psn-l@............... Sent: Saturday, October 24, 2009 2:38 PM Subject: Re: TELEDYNE-GEOTECH HELICORDER James, Perhaps Geotech might have such as Al Hrubetz suggests...but being as ink stylus writing went out long ago...one may have to resort to other (surplus...read: junk or unknown condition substitutes) brands. The tips of worn pens usually gets worn out or abrasively flattened to where the ink flow smears all over the place; rather than flow evenly and write with little snagging "sharpened" pen tip effect...as you likely already know. I've never figured out how to "round out" or "smooth the outside and inside" of the writing tips to effectively, re-use such. Sometimes....the pen tip isn't exactly flat to the writing drum surface (the prior tube gets bent up, down or sideways...and this condition will give the impression that the pen isn't working...you might check that first....in all directions of movement. Heated (electrical resistance) tips might be a consideration, but the thermal paper prices are out of this world for obtaining and prices are the same of course. If you want to eventually take it email private, I do have a "junk box" assortment of other brand pens; that ~~~might~~~be mechanically adaptable if all else fails. It might involve cutting, solder or glue or other monstrocities of the original pen. If you have a accurate micrometer or vernier gauge that tells the outside and (rough) inside diameter of the pen; that "might" help. Chances are probably poor for a match; and it may involve you "adapting" a different brand or size. There is zero guarantee of my junk; they may be worn out also, or dried ink clogged; I've not used such for many years...it can be extremely frustrating to fuss with and get a "good" one. Meredith Lamb On Sat, Oct 24, 2009 at 1:56 PM, James Allen <_jcallen1@............ (mailto:jcallen1@............ > wrote: Does anyone have or know of a place where I can obtain a replacement ink dispensing writing stylus for a Teledyne-Geotech Helicorder? Thanks James Allen
James,
As of June, 2008, Geotech Instruments price fo= r a=20 Replacement heat writing stylus Model 38548 was $75.00.  Five hundred= =20 sheets of heat writing paper was $255.00
Al
 
In a message dated 10/24/2009 5:03:41 P.M. Central Daylight Time,=20 jcallen1@........... writes:
Thanks Al and Meredith regarding sourci= ng ink=20 writing stylus for helicorder.  I guess I will stick with the therm= al=20 stylus that is on the unit for the time being and contact Geotech and se= e if I=20 can afford an exact replacement.
James Allen
----- Original Message -----
= From:=20 meredith lamb
To: psn-l@..............
Sent: Saturday, October 24, 200= 9 2:38=20 PM
Subject: Re: TELEDYNE-GEOTECH= =20 HELICORDER

James,
 
Perhaps Geotech might have such as Al Hrubetz suggests...but bein= g as=20 ink stylus writing went out
long ago...one may have to resort to other (surplus...read: junk= or=20 unknown condition substitutes) brands.
The tips of worn pens usually gets worn out or abrasively flatten= ed to=20 where the ink flow smears all over
the place; rather than flow evenly and write with little snagging= =20 "sharpened" pen tip effect...as you likely already know.  I've ne= ver=20 figured out how to "round out" or "smooth the outside and inside" of= =20 the writing tips to effectively, re-use such.
 
Sometimes....the pen tip isn't exactly flat to the writing drum= surface=20 (the prior tube gets bent up, down
or sideways...and this condition will give the impression that th= e pen=20 isn't working...you might check
that first....in all directions of movement.
 
Heated (electrical resistance) tips might be a consideration, but= the=20 thermal paper prices are out of this
world for obtaining and prices are the same of course.
 
If you want to eventually take it email private, I do have a "jun= k box"=20 assortment of other brand pens; that ~~~might~~~be mechanically adapta= ble if=20 all else fails.  It might involve cutting, solder or glue or=20 other
monstrocities of the original pen.  If you have a accurate= =20 micrometer or vernier gauge that tells the outside and (rough) inside= =20 diameter of the pen; that "might" help.  Chances are probabl= y poor=20 for a match; and it may involve you "adapting" a different brand or=20 size.  There is zero guarantee of my junk; they may be worn out= also,=20 or dried ink clogged; I've not used such for many years...it can=20 be extremely frustrating to fuss with and get a "good" one.
 
Meredith Lamb
   

On Sat, Oct 24, 2009 at 1:56 PM, James Allen= <jcallen1@...........>=20 wrote:
Does anyone have or know of a place= where I=20 can obtain a replacement ink dispensing writing stylus for a=20 Teledyne-Geotech Helicorder?
Thanks
James Allen
 
=
Subject: Re: Hypodermic Tubing From: ChrisAtUpw@....... Date: Sun, 25 Oct 2009 11:40:26 EDT =20 In a message dated 25/10/2009, jcallen1@........... writes: For some time some PSN members were using hypodermic needles to build ink= =20 pens. You simply grind the point off and have a precesion tip that can= =20 then be connected to the reservoir using a capillary feed tube. We learne= d the=20 process from Howard who used this design back in the first Bay area=20 seismic station way before our time in the 40=E2=80=99s. I ran two drum= recorders back=20 around 1990 and Jan Froom currently has a display station at Bonfante Gar= dens=20 in Gilroy CA that has a permanent display he put together for them=20 Regards, Steve Hammond PSN Aptos, CA Hi James, =20 If you want to get ready supplies of fine SS hypodermic tubing see=20 _www.smallparts.com_ (http://www.smallparts.com) They have a very wide= range.=20 You can vary the flow rate by inserting a variable length of wire through= =20 the ink reservoir and into the capillary tube. It would probably be easie= r=20 to get fine Nichrome wire than stainless steel.=20 Alternatively, some companies used to make pens with a coarse tube to= =20 the reservoir and a fine 'nib' tube pushed into in the other end. There= are=20 only a limited range of hypodermic needles produced and some suppliers=20 refuse to supply non medics, or only sell in boxed quantities. =20 Regards, =20 Chris Chapman
In a message dated 25/10/2009, jcallen1@........... writes:

For=20 some time some PSN members were using hypodermic needles to build ink pe= ns.=20 You simply grind the point off and have a precesion tip that  can= then be=20 connected to the reservoir using a capillary feed tube. We learned the= process=20 from Howard who used this design back in the first Bay area seismic stat= ion=20 way before our time in the 40=E2=80=99s. I ran two drum recorders back= around 1990 and=20 Jan Froom currently has a display station at Bonfante Gardens  in= Gilroy=20 CA that has a permanent display he put together for them Regards,=20 Steve Hammond PSN Aptos, CA
Hi James,
    
    If you want to get ready supplies of fine SS= =20 hypodermic tubing see www.smallparts= ..com=20 They have a very wide range. You can vary the flow rate by inserting a var= iable=20 length of wire through the ink reservoir and into the capillary tube. It= would=20 probably be easier to get fine Nichrome wire than stainless steel.
    Alternatively, some companies used to make pe= ns=20 with a coarse tube to the reservoir and a fine 'nib' tube pushed into in= the=20 other end. There are only a limited range of hypodermic needles produced= and=20 some suppliers refuse to supply non medics, or only sell in boxed=20 quantities.
 
    Regards,
 
    Chris Chapman
Subject: Re: Hypodermic Tubing From: "James Allen" jcallen1@........... Date: Sun, 25 Oct 2009 09:48:56 -0700 Thanks Chris, Steve, Al, and Meredith for all your help. I secured some = very thin capillary tubing and a hypo. needle. Will test approach and = then try to cobble together attaching it to the existing stylus on the = helicorder. Will let the list know results. It really is great knowing = one is not alone on this quest. James Allen Cerritos, Ca. ----- Original Message -----=20 From: ChrisAtUpw@.......... To: psn-l@................. Sent: Sunday, October 25, 2009 8:40 AM Subject: Re: Hypodermic Tubing In a message dated 25/10/2009, jcallen1@........... writes: For some time some PSN members were using hypodermic needles to = build ink pens. You simply grind the point off and have a precesion tip = that can then be connected to the reservoir using a capillary feed = tube. We learned the process from Howard who used this design back in = the first Bay area seismic station way before our time in the = 40=E2=80=99s. I ran two drum recorders back around 1990 and Jan Froom = currently has a display station at Bonfante Gardens in Gilroy CA that = has a permanent display he put together for them Regards, Steve Hammond = PSN Aptos, CA Hi James, =20 If you want to get ready supplies of fine SS hypodermic tubing see = www.smallparts.com They have a very wide range. You can vary the flow = rate by inserting a variable length of wire through the ink reservoir = and into the capillary tube. It would probably be easier to get fine = Nichrome wire than stainless steel.=20 Alternatively, some companies used to make pens with a coarse tube = to the reservoir and a fine 'nib' tube pushed into in the other end. = There are only a limited range of hypodermic needles produced and some = suppliers refuse to supply non medics, or only sell in boxed quantities. Regards, Chris Chapman =EF=BB=BF
Thanks Chris, Steve, Al, and Meredith for all your help.  I = secured=20 some very thin capillary tubing and a hypo. needle.  Will test = approach and=20 then try to cobble together attaching it to the existing stylus on the=20 helicorder.  Will let the list know results.  It really is = great=20 knowing one is not alone on this quest.
James Allen
Cerritos, Ca.
----- Original Message -----
From:=20 ChrisAtUpw@.......
Sent: Sunday, October 25, 2009 = 8:40=20 AM
Subject: Re: Hypodermic = Tubing

In a message dated 25/10/2009, jcallen1@........... = writes:

For=20 some time some PSN members were using hypodermic needles to build = ink pens.=20 You simply grind the point off and have a precesion tip that =  can then=20 be connected to the reservoir using a capillary feed tube. We = learned the=20 process from Howard who used this design back in the first Bay area = seismic=20 station way before our time in the 40=E2=80=99s. I ran two drum = recorders back=20 around 1990 and Jan Froom currently has a display station at = Bonfante=20 Gardens  in Gilroy CA that has a permanent display he put = together for=20 them Regards,=20 Steve Hammond PSN Aptos, = CA

Hi James,
    
    If you want to get ready supplies of fine = SS=20 hypodermic tubing see www.smallparts.com They have a = very wide=20 range. You can vary the flow rate by inserting a variable length of = wire=20 through the ink reservoir and into the capillary tube. It would = probably be=20 easier to get fine Nichrome wire than stainless steel.
    Alternatively, some companies used to = make pens=20 with a coarse tube to the reservoir and a fine 'nib' tube pushed into = in the=20 other end. There are only a limited range of hypodermic needles = produced and=20 some suppliers refuse to supply non medics, or only sell in boxed=20 quantities.
 
    Regards,
 
    Chris=20 Chapman
Subject: Re: Hypodermic Tubing From: meredith lamb paleoartifact@......... Date: Sun, 25 Oct 2009 12:15:16 -0600 "Drummers", are a hardy and tenacious lot; and through the years it seems that the public really likes to observe such mechanisms when and where they can. It can be fun stuff; but you have to be patient and maintenance is a daily requirement task. Unfortunately its obviously almost impossible to "share" their records, or delve into computer keystroke deviations that could be more readily manipulated and yield all kinds of results; and at the same time store their records handily. Yes, I've been there, done that; and perhaps even yet longer with strip chart recorders with long "conveyor belt" chart paper modifications. Those were alittle more accomodating as the servo power mechanisms allowed problems with pen and ink monstrosities to minimize the added weight on the servo drive/s. Occasionally, the zipping, whipping servo pen movments noise was the only seismic audio quake alarm "system"....if I was around to hear such. It can be exciting when "things" are jumping back and forth! Its quite a step to go from drums to computers...especially if one has no experience with such. However eventually one can pick up all the aspects and then finds that the computer approach really offers a greater satisfaction; and best of all, one can build up other seismometers and add them to the computer readily....after all, you've wondered about that missing E-W orientation seismometer or missing vertical you've not previously had any opportunity to experience. The computer allows you more time and space to partake of other seismic learning discoveries. Then comes a time when you need to do something with that old and heavy drum recorder. I only tore up one once. The drum itself is usually the only "high potential" salvagable item; they often can be containers for small seismo's, and if I remember right, that one had two small brass counterweights inside (too balance rotation originally); which could be used a mass. The squarish drum recorder frame itself "could be" a excellent seismometer base and upright support for misc., attachments. Of course all this depends on the individual insight and innovation goals. More often than not; even if you want to sell such; you won't find a buyer for the price you may want. Selling it for metal scrap, is probably a heart rending thing to do; and it likely won't be worth the time and gas to take it to a metal scrap dealer; for the little money they may give you for it. Often; they may not even buy such; they want it prior broken down into specific metals to save themselves labor costs and enhance profits. One might as well do the salvage thing if you anticipate building a homebrew seismometer....some of that stuff...."might" work. On the other hand...I still have the drum shell, but its not yet been actually used...yet... Take care, Meredith Lamb On Sun, Oct 25, 2009 at 10:48 AM, James Allen wrote: > Thanks Chris, Steve, Al, and Meredith for all your help. I secured some > very thin capillary tubing and a hypo. needle. Will test approach and then > try to cobble together attaching it to the existing stylus on the > helicorder. Will let the list know results. It really is great knowing one > is not alone on this quest. > James Allen > Cerritos, Ca. > > > >
=A0
"Drummers", are a hardy=A0and tenacious lot; and through the= years it seems that the public really likes
to observe such mechanisms when and where they can.=A0 It can be fun s= tuff; but you have to be
patient and maintenance is a daily requirement task.
=A0
Unfortunately its obviously almost impossible to "share" the= ir records, or delve into computer keystroke deviations that could be more = readily manipulated and yield all kinds of results; and at the same time
store their records handily.
=A0
Yes, I've been there, done that; and perhaps even yet longer with = strip chart recorders with long
"conveyor belt" chart paper modifications.=A0 Those were ali= ttle more accomodating as the servo power
mechanisms allowed problems with pen and ink monstrosities to minimize= the added weight on the
servo drive/s.=A0 Occasionally, the zipping, whipping servo pen movmen= ts noise was the only seismic audio
quake alarm "system"....if I was around to hear such.=A0 It = can be=A0exciting when "things" are jumping
back and forth!
=A0
Its quite a step to go from drums to computers...especially if one has= no experience with such.
However eventually one can pick up all the aspects and then finds that= the computer approach really
offers a greater satisfaction; and best of all, one can build up other= seismometers and add them to
the computer readily....after all, you've wondered about that miss= ing E-W orientation seismometer
or missing vertical you've not previously had any opportunity to e= xperience.=A0 The computer allows you
more time and space to partake of other seismic learning discoveries.<= /div>
=A0=A0
Then comes a time when you need to do something with that old and heav= y drum recorder.=A0 I only
tore up one once.=A0=A0The drum itself is usually the only "high = potential" salvagable item; they often can be
containers for small seismo's, and if I remember right, that one= =A0had two small brass counterweights
inside (too balance rotation originally); which could be used a mass.= =A0 The squarish drum recorder frame itself "could be" a excellen= t seismometer base and upright support for misc., attachments.=A0 Of course= all this depends on the=A0individual insight and innovation goals.=A0 More= often than not; even if you want to sell such; you won't find a buyer = for the price you may want.=A0 Selling it for metal scrap, is probably a he= art rending thing to do; and it likely won't be worth the time and gas = to take it to a metal scrap dealer; for the little money=A0they may give yo= u for it.=A0=A0Often; they may not even buy such; they want it prior broken= down into specific metals to save themselves labor costs and enhance profi= ts.=A0 One might as well do the salvage thing if you anticipate building a = homebrew seismometer....some of that stuff...."might" work.=A0 On= the other hand...I still have the drum shell, but its not yet been actuall= y used...yet...
=A0
Take care, Meredith Lamb
=A0
=A0=A0
=A0
=A0
=A0
On Sun, Oct 25, 2009 at 10:48 AM, James Allen <jcallen1@verizo= n.net> wrote:
Thanks Chris, Steve, Al, and Meredith for all your help.=A0 I secured = some very thin capillary tubing and a hypo. needle.=A0 Will test approach a= nd then try to cobble together attaching it to the existing stylus on the h= elicorder.=A0 Will let the list know results.=A0 It really is great knowing= one is not alone on this quest.
James Allen
Cerritos, Ca.
=A0
Subject: Re: Hypodermic Tubing From: George Bush ke6pxp@....... Date: Sun, 25 Oct 2009 12:45:00 -0700 James- I have a drum recorder that was originaly built=20 by Howard Grebin and he built an ink pen like you=20 are describing. He used capillary tubing, hypo=20 needle and sheet brass shim stock all=20 soft-soldered together. It has performed flawlessly for me for decades. I would be glad to send you a picture of the pen=20 detail so you could see how he attached it to the galvanometer. George At 09:48 AM 10/25/2009, you wrote: >=EF=BB=BF >Thanks Chris, Steve, Al, and Meredith for all=20 >your help. I secured some very thin capillary=20 >tubing and a hypo. needle. Will test approach=20 >and then try to cobble together attaching it to=20 >the existing stylus on the helicorder. Will let=20 >the list know results. It really is great=20 >knowing one is not alone on this quest. >James Allen >Cerritos, Ca. >----- Original Message ----- >From: ChrisAtUpw@....... >To: psn-l@.............. >Sent: Sunday, October 25, 2009 8:40 AM >Subject: Re: Hypodermic Tubing > >In a message dated 25/10/2009,=20 >jcallen1@........... writes: > >For some time some PSN members were using=20 >hypodermic needles to build ink pens. You simply=20 >grind the point off and have a precesion tip=20 >that can then be connected to the reservoir=20 >using a capillary feed tube. We learned the=20 >process from Howard who used this design back in=20 >the first Bay area seismic station way before=20 >our time in the 40=E2=80=99s. I ran two drum recorders=20 >back around 1990 and Jan Froom currently has a=20 >display station at Bonfante Gardens in Gilroy=20 >CA that has a permanent display he put together=20 >for them Regards, Steve Hammond PSN Aptos, CA > >Hi James, > > If you want to get ready supplies of fine=20 > SS hypodermic tubing see=20 > www.smallparts.com=20 > They have a very wide range. You can vary the=20 > flow rate by inserting a variable length of=20 > wire through the ink reservoir and into the=20 > capillary tube. It would probably be easier to=20 > get fine Nichrome wire than stainless steel. > Alternatively, some companies used to make=20 > pens with a coarse tube to the reservoir and a=20 > fine 'nib' tube pushed into in the other end.=20 > There are only a limited range of hypodermic=20 > needles produced and some suppliers refuse to=20 > supply non medics, or only sell in boxed quantities. > > Regards, > > Chris Chapman George Bush Sea Ranch, CA, USA 38.73775N, 123.48882W=20 James-

I have a drum recorder that was originaly built by Howard Grebin and he built an ink pen like you are describing. He used capillary tubing, hypo needle and sheet brass shim stock all soft-soldered together. It has performed flawlessly for me for decades.

I would be glad to send you a picture of the pen detail so you could see how he attached it to the galvanometer.

George


At 09:48 AM 10/25/2009, you wrote:
=EF=BB=BF
Thanks Chris, Steve, Al, and Meredith for all your help.  I secured some very thin capillary tubing and a hypo. needle.  Will test approach and then try to cobble together attaching it to the existing stylus on the helicorder.  Will let the list know results.  It really is great knowing one is not alone on this quest.
James Allen
Cerritos, Ca.
----- Original Message -----
From: ChrisAtUpw@.......
To: psn-l@..............
Sent: Sunday, October 25, 2009 8:40 AM
Subject: Re: Hypodermic Tubing

In a message dated 25/10/2009, jcallen1@........... writes:

For some time some PSN members were using hypodermic needles to build ink pens. You simply grind the point off and have a precesion tip that  can then be connected to the reservoir using a capillary feed tube. We learned the process from Howard who used this design back in the first Bay area seismic station way before our time in the 40=E2=80=99s. I ra= n two drum recorders back around 1990 and Jan Froom currently has a display station at Bonfante Gardens  in Gilroy CA that has a permanent display he put together for them Regards, Steve Hammond PSN Aptos, CA

Hi James,
   
    If you want to get ready supplies of fine SS hypodermic tubing see www.smallparts.com They have a very wide range. You can vary the flow rate by inserting a variable length of wire through the ink reservoir and into the capillary tube. It would probably be easier to get fine Nichrome wire than stainless steel.
    Alternatively, some companies used to make pens with a coarse tube to the reservoir and a fine 'nib' tube pushed into in the other end. There are only a limited range of hypodermic needles produced and some suppliers refuse to supply non medics, or only sell in boxed quantities.
 
    Regards,
 
    Chris Chapman


George Bush
Sea Ranch, CA, USA
38.73775N, 123.48882W Subject: Event 091025.105300 as seen from GVA ?? From: "Geoffrey" gmvoeth@........... Date: Sun, 25 Oct 2009 13:30:07 -0700 Hey guys; In Winquake event file: 091025.105300 from GVA When I integrate this event the ground seems to drop at somewhere in the S or L wave and does not return to normal ? Does anyone understand this integrated waveform ? It looks to me like only the DC blocker circuit is returning the signal to its baseline. I have seen this before but do not understand it. In my wildest imagination I can in no other way explain this results of the integration. Is Arizona slowly sinking into the Earth ? Will we have another ocean where there used to be desert ? __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Hypodermic Tubing From: "James Allen" jcallen1@........... Date: Sun, 25 Oct 2009 13:55:52 -0700 Thanks George for the offer. I would really appreciate receiving a = picture of the pen assembly. My email address is: = jcallen1@............ Thanks=20 James Allen ----- Original Message -----=20 From: George Bush=20 To: psn-l@................. Sent: Sunday, October 25, 2009 12:45 PM Subject: Re: Hypodermic Tubing James- I have a drum recorder that was originaly built by Howard Grebin and = he built an ink pen like you are describing. He used capillary tubing, = hypo needle and sheet brass shim stock all soft-soldered together. It = has performed flawlessly for me for decades. I would be glad to send you a picture of the pen detail so you could = see how he attached it to the galvanometer. George At 09:48 AM 10/25/2009, you wrote: =C3=AF=C2=BB=C2=BF=20 Thanks Chris, Steve, Al, and Meredith for all your help. I secured = some very thin capillary tubing and a hypo. needle. Will test approach = and then try to cobble together attaching it to the existing stylus on = the helicorder. Will let the list know results. It really is great = knowing one is not alone on this quest. James Allen Cerritos, Ca. ----- Original Message -----=20 From: ChrisAtUpw@.......... To: psn-l@................. Sent: Sunday, October 25, 2009 8:40 AM Subject: Re: Hypodermic Tubing In a message dated 25/10/2009, jcallen1@........... writes: For some time some PSN members were using hypodermic needles to = build ink pens. You simply grind the point off and have a precesion tip = that can then be connected to the reservoir using a capillary feed = tube. We learned the process from Howard who used this design back in = the first Bay area seismic station way before our time in the = 40=C3=A2=E2=82=AC=E2=84=A2s. I ran two drum recorders back around 1990 = and Jan Froom currently has a display station at Bonfante Gardens in = Gilroy CA that has a permanent display he put together for them Regards, = Steve Hammond PSN Aptos, CA Hi James, =20 If you want to get ready supplies of fine SS hypodermic tubing = see www.smallparts.com They have a very wide range. You can vary the = flow rate by inserting a variable length of wire through the ink = reservoir and into the capillary tube. It would probably be easier to = get fine Nichrome wire than stainless steel.=20 Alternatively, some companies used to make pens with a coarse = tube to the reservoir and a fine 'nib' tube pushed into in the other = end. There are only a limited range of hypodermic needles produced and = some suppliers refuse to supply non medics, or only sell in boxed = quantities. Regards, Chris Chapman George Bush Sea Ranch, CA, USA 38.73775N, 123.48882W =EF=BB=BF

Thanks George for the offer. = I would really appreciate receiving a picture of the pen=20 assembly.  My email address is:  jcallen1@............
Thanks
James Allen
----- Original Message -----
From:=20 George = Bush
Sent: Sunday, October 25, 2009 = 12:45=20 PM
Subject: Re: Hypodermic = Tubing

James-

I have a drum recorder that was originaly = built=20 by Howard Grebin and he built an ink pen like you are describing. He = used=20 capillary tubing, hypo needle and sheet brass shim stock all = soft-soldered=20 together. It has performed flawlessly for me for decades.

I = would be=20 glad to send you a picture of the pen detail so you could see how he = attached=20 it to the galvanometer.

George


At 09:48 AM = 10/25/2009, you=20 wrote:
=C3=AF=C2=BB=C2=BF =
Thanks Chris, Steve, Al,=20 and Meredith for all your help.  I secured some very thin = capillary=20 tubing and a hypo. needle.  Will test approach and then try to = cobble=20 together attaching it to the existing stylus on the = helicorder.  Will=20 let the list know results.  It really is great knowing one is = not alone=20 on this quest.
James Allen
Cerritos, Ca.
----- Original Message -----
From: ChrisAtUpw@.......=20
To: psn-l@..............=20
Sent: Sunday, October 25, 2009 8:40 AM
Subject: Re: Hypodermic Tubing

In a message dated 25/10/2009, jcallen1@...........=20 writes:

For some time some PSN members were using hypodermic needles = to=20 build ink pens. You simply grind the point off and have a = precesion tip=20 that  can then be connected to the reservoir using a = capillary feed=20 tube. We learned the process from Howard who used this design = back in=20 the first Bay area seismic station way before our time in the = 40=C3=A2=E2=82=AC=E2=84=A2s. I=20 ran two drum recorders back around 1990 and Jan Froom currently = has a=20 display station at Bonfante Gardens  in Gilroy CA that has = a=20 permanent display he put together for them Regards, Steve = Hammond PSN=20 Aptos, CA

Hi James,
   
    If you want to get ready supplies of fine = SS=20 hypodermic tubing see www.smallparts.com They = have a very=20 wide range. You can vary the flow rate by inserting a variable = length of=20 wire through the ink reservoir and into the capillary tube. It = would=20 probably be easier to get fine Nichrome wire than stainless steel. =
    Alternatively, some companies used to make = pens=20 with a coarse tube to the reservoir and a fine 'nib' tube pushed = into in=20 the other end. There are only a limited range of hypodermic = needles=20 produced and some suppliers refuse to supply non medics, or only = sell in=20 boxed quantities.

 
    Regards,

 
    Chris = Chapman


George Bush
Sea Ranch, CA, USA
38.73775N, = 123.48882W=20 Subject: Re: Event 091025.105300 as seen from GVA ?? From: Larry Cochrane lcochrane@.............. Date: Sun, 25 Oct 2009 16:08:43 -0700 Hi Geoffrey, This is happening because your system is saturation. Looking at your event file it looks like you are using a 8 Bit A/D converter. Upgrading to a 12 or higher bit converter would give you a lot more dynamic range so this would happen less often. Regards, Larry Cochrane Redwood City, PSN Geoffrey wrote: > Hey guys; > > In Winquake > > event file: 091025.105300 from GVA > When I integrate this event the ground seems > to drop at somewhere in the S or L wave and does > not return to normal ? > > Does anyone understand this integrated waveform ? > > It looks to me like only the DC blocker circuit > is returning the signal to its baseline. > > I have seen this before but do not understand it. > > In my wildest imagination I can in no other way > explain this results of the integration. > > Is Arizona slowly sinking into the Earth ? > Will we have another ocean where there used to be desert ? > > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Event 091025.105300 as seen from GVA ?? From: "Geoffrey" gmvoeth@........... Date: Sun, 25 Oct 2009 17:20:03 -0700 Thanks, that sounds very reasonable. I may consider changing things But think not able to go higher than 10 bits since the lower two seem noisy and I do not understand why since with no input but a dummy 5K resistor I see the lower bits bouncing with no input at all. I have not played with this noise recently just am using 8 or 9 bits with 9 bits for a 6Db of gain boost. Using 10 will require a program change as well as testing to see this does alteration to a greater bit size does not change my sample rate which is very sensitive to exactly how the DOS is programmed. Mainly the kind of memory used like HUGE or Virtual. Virtual in power basic seems considerably slower than Huge. I do a lot of stuff between each loop of sample taking (such as time calibration) and it seems slow or fast machine the limiting factor is staying in REAL mode memory instead of virtual mode within DOS. Real Mode = first 1MB Protected Mode = all above 1MB EMS seems faster than XMS. ???? Do not understand any of this but I DO need consistent speed between each sample taking. The programming is critical to achieving a steady sample rate equal to the tic timer within the computer. Possibly some commands will disable the interrupt timer used for the tic counter. Simply lowering the gain or possibly using a log amplifier may be other choices for me to consider. regards geoff ----- Original Message ----- From: "Larry Cochrane" To: Sent: Sunday, October 25, 2009 4:08 PM Subject: Re: Event 091025.105300 as seen from GVA ?? > Hi Geoffrey, > > This is happening because your system is saturation. Looking at your event file it > looks like you are using a 8 Bit A/D converter. Upgrading to a 12 or higher bit > converter would give you a lot more dynamic range so this would happen less often. > > Regards, > Larry Cochrane > Redwood City, PSN > > Geoffrey wrote: >> Hey guys; >> >> In Winquake >> >> event file: 091025.105300 from GVA >> When I integrate this event the ground seems >> to drop at somewhere in the S or L wave and does >> not return to normal ? >> >> Does anyone understand this integrated waveform ? >> >> It looks to me like only the DC blocker circuit >> is returning the signal to its baseline. >> >> I have seen this before but do not understand it. >> >> In my wildest imagination I can in no other way >> explain this results of the integration. >> >> Is Arizona slowly sinking into the Earth ? >> Will we have another ocean where there used to be desert ? >> >> __________________________________________________________ >> >> Public Seismic Network Mailing List (PSN-L) >> >> To leave this list email PSN-L-REQUEST@.............. with >> the body of the message (first line only): unsubscribe >> See http://www.seismicnet.com/maillist.html for more information. >> > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Event 091025.105300 as seen from GVA ?? From: ChrisAtUpw@....... Date: Sun, 25 Oct 2009 21:47:19 EDT In a message dated 26/10/2009, gmvoeth@........... writes: But think not able to go higher than 10 bits since the lower two seem noisy and I do not understand why since with no input but a dummy 5K resistor I see the lower bits bouncing with no input at all. Hi Geoff, Have you checked your electricity supply that line really is line and return is ~zero? Regards, Chris Chapman
In a message dated 26/10/2009, gmvoeth@........... writes:
But=20 think not able to go higher than 10 bits since the lower two seem noisy= and I=20 do not understand why since with no input but a dummy 5K resistor I see= the=20 lower bits bouncing with no input at all.
Hi Geoff,
 
    Have you checked your electricity supply that= line=20 really is line and return is ~zero?
 
    Regards,
 
    Chris Chapman
Subject: Re: Event 091025.105300 as seen from GVA ?? From: "Geoffrey" gmvoeth@........... Date: Tue, 27 Oct 2009 01:50:52 -0700 Howdy From GVA; The electrical grounds in the desert here are practically non existent and you need to create your own. I have used a general purpose tester that tells me my wiring is correct but more than likely the ground is very high resistance. I am tying B- to earth ground even tho I use a split supply since it is the only common ground I am able to share with the devices I have. There are 12800V lines I believe within 50 ft of this place and seem to create a terrific AC field over the whole area. I am glad to see someone take an interest in this ground thing since I have over the years never got it exactly right. Since reprogramming for 12 bits reducing my time to 30 minutes of recording I now see a strong artifact I believe to be alised from a higher frequency. I had to reduce my amplifier gain by a factor of eight so this artifact must be presenting itself directly to the A/D converter but still not sure. Amplifier GAIN FROM X10,000 to X1250 I believe at one hertz. The A/D I use went from 8mv per count to 1mv per count. The overall sensitivity should be the same for seismic signals but has increased for electrical artifacts. I can provide you with raw INTEGER data but not the final results of any analysis since I also must rewrite the display routine to create WINQUAKE and the BMP and WAVE files I regularly use. This raw data with associated data may be of use to anyone wanting to understand what I'm dealing with here. I have noticed a different picture with 12 bits but not sure I am able to get full scale since my opamps will not go rail to rail. The picture looks promising even tho there are electrical artifacts present. You would not believe the ground noise I have here at audio frequencies this place a cornucopia filled with air conditioners running all at the same time. Thanks for the reply. I'm trying now to straighten the 12 bit thing out and will be offline awhile. I understand the basic idea of a ground but have only been able to make it partially work. So I'm obviously lacking understanding. My formal training is military schools and civilian associates degree which as anyone knows only serves to get ones foot in the door and nothing like those 500 series courses of study. I find this all rather entertaining though. Best regards; geoff ----- Original Message ----- From: To: Sent: Sunday, October 25, 2009 6:47 PM Subject: Re: Event 091025.105300 as seen from GVA ?? > > In a message dated 26/10/2009, gmvoeth@........... writes: > > But think not able to go higher than 10 bits since the lower two seem > noisy and I do not understand why since with no input but a dummy 5K resistor I > see the lower bits bouncing with no input at all. > > > > Hi Geoff, > > Have you checked your electricity supply that line really is line and > return is ~zero? > > Regards, > > Chris Chapman > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Hypodermic Tubing and Inking From: George Bush ke6pxp@....... Date: Tue, 27 Oct 2009 11:17:43 -0700 Hi James (and to the list, it might help someone else)- I think you were right about the rubber bulb, the bottle was off of a commercial strip-chart recorder. I don't use a rubber bulb, I just gently squeeze the plastic bottle (see below). Yes, there is a trick to it, but the BIGGER trick is to keep it flowing once you get it flowing! Let me start with 1- ink, then 2- cleaning a gummed-up pen, 3- filling, and finally 4- operating (this is sort of the sequence of events) INK- I use Sheaffer's Skrip fountain pen ink. It is easy to get, is water soluble/cleanable (use ammonia to remove ink from fingers), and can be cleaned from completely plugged-dry pen tubing (see below). PLUGGED PEN ASSEMBLY- I take the whole metal pen assembly (not the plastic capillary tubing!), put it in an old pot and BOIL IT for a few minutes (don't let your wife catch you doing this!) Take it out and use a syringe to force water through the re-attached capillary tubing and pen. I use tap water for boiling and clearing, but I always do a finish rinse with distilled water using very clean utensils (pans/syringe, etc). Sometimes I have to soak and boil again. FILLING- I use blunt-tipped industrial syringes of about 10cc volume so that one squirt fills my bottle. One cheap source of syringes is www.sciplus.com. The small ink bottle cap has a long metal tube to the bottom that the plastic capillary connects the pen to and a very short tube to allow air into the top of the bottle. Have the plastic tubing connected to the bottle and the pen before starting the first fill (I have gone years without needing to take the tubing off).I fill it by unscrewing the cap and gently injecting the ink directly into the bottle (try to not get bubbles). To fill the tube the first time, fill bottle with ink about 2/3rds, screw cap back on firmly to get an air seal around the cap. place a small square of absorbent tissue under the tip of the pen as it rests on the drum paper, put finger over top tube (if you use one), and gently squeeze the plastic bottle to fill the tube and pen. Continue squeezing until you get quite a bit of ink on the tissue. Important, do not let bottle suck ink back in when you release! While still squeezing, unblock top tube then unsqueeze. Remove tissue and you are in business. Top of bottle must be able to get air in (or else it will just stop in a few days, or burp ink out on the paper). Sometimes the short tube gets a dried drop of ink in it and is blocked. I don't trust it and so I always leave the cap loosely screwed on OPERATING- Adjust the height of bottle to be just a bit above the pen tip on the drum. Capillary action at the pen/paper interface will actually 'pull' the ink in and gravity will also help. I am able to leave the bottle at one place and have it work perfectly as the ink level goes from full to nearly empty. If there are any air bubbles in the line, the pen will stop inking. Catch this quickly or the ink will dry in the pen, it needs the ink to move through it to keep itself clean. Just do the tissue, plug and squeeze routine to get it started again. If the pen is skipping it is telling you that something is wrong and you should check ink bottle-height, use a tissue to see if ink will flow, and check ink level in bottle. NEVER let the ink get below the bottom of the tube down into the bottle! If it does, you go back to square one! I drew a big line on my bottle at about 1/4 and that is my signal to re-ink. I occasionally get a line that is too wide. Ink bottle too high can cause this, just move bottle down.. In the Summer when dust blows in, the pen will pick it up and also give a wide trace. Procedure- I change paper about every three days. I have a micro-switch that will turn the drum drive motor off at the end of the travel and I frequently get an inkblot on the end of the trace. While ugly and data is lost, this is good for the pen as it keeps the ink flowing until you can change paper. When I change paper I gently clean the pen tip with a tissue wiping-off the bit of ink that has dried there and check ink level in the bottle and refill as necessary. I can usually go a week or 10 days before refilling. When finished refilling I hold the syringe vertical and aim it at a piece of tissue and pump air in and out a few times to try to get all the ink out. Shaking and repeating also will get some additional ink out of the syringe (don't do this over carpets!). If I go on a trip for up to a week, I do nothing. if I am away longer I will remove all ink from the system (by squeezing the bottle), wash in clean distilled water, blow it dry and store in a safe place. These procedures have worked for me for years and may be useful to you too. George At 08:14 PM 10/26/2009, you wrote: >Hello again George. I forgot to ask how do you get the ink to start >flowing. I noticed that the cap to the ink bottle has what appears >as two openings, one for the capillary tubing and a larger open >one. Is the larger one for some type of rubber bulb to force the >ink to start flowing through the capillary tubing? >James Allen George Bush Sea Ranch, CA, USA 38.73775N, 123.48882W Hi James (and to the list, it might help someone else)-

I think you were right about the rubber bulb, the bottle was off of a commercial strip-chart recorder. I don't use a rubber bulb, I just gently squeeze the plastic bottle (see below). Yes, there is a trick to it, but the BIGGER trick is to keep it flowing once you get it flowing!

Let me start with 1- ink, then 2- cleaning a gummed-up pen, 3- filling, and finally 4- operating (this is sort of the sequence of events)

INK- I use Sheaffer's Skrip fountain pen ink. It is easy to get, is water soluble/cleanable (use ammonia to remove ink from fingers), and can be cleaned from completely plugged-dry pen tubing (see below).

PLUGGED PEN ASSEMBLY- I take the whole metal pen assembly (not the plastic capillary tubing!), put it in an old pot and BOIL IT for a few minutes (don't let your wife catch you doing this!) Take it out and use a syringe to force water through the re-attached capillary tubing and pen. I use tap water for boiling and clearing, but I always do a finish rinse with distilled water using very clean utensils (pans/syringe, etc). Sometimes I have to soak and boil again.

FILLING- I use blunt-tipped industrial syringes of about 10cc volume so that one squirt fills my bottle. One cheap source of syringes is www.sciplus.com. The small ink bottle cap has a long metal tube to the bottom that the plastic capillary connects the pen to and a very short tube to allow air into the top of the bottle. Have the plastic tubing connected to the bottle and the pen before starting the first fill (I have gone years without needing to take the tubing off).I fill it by unscrewing the cap and gently injecting the ink directly into the bottle (try to not get bubbles). To fill the tube the first time, fill bottle with ink about 2/3rds, screw cap back on firmly to get an air seal around the cap. place a small square of absorbent tissue under the tip of the pen as it rests on the drum paper, put finger over top tube (if you use one), and gently squeeze the plastic bottle to fill the tube and pen. Continue squeezing until you get quite a bit of ink on the tissue. Important, do not let bottle suck ink back in when you release! While still squeezing, unblock top tube then unsqueeze. Remove  tissue and you are in business. Top of bottle must be able to get air in (or else it will just stop in a few days, or burp ink out on the paper). Sometimes the short tube gets a dried drop of ink in it and is blocked. I don't trust it and so I always leave the cap loosely screwed on

OPERATING- Adjust the height of bottle to be just a bit above the pen tip on the drum. Capillary action at the pen/paper interface will actually 'pull' the ink in and gravity will also help. I am able to leave the bottle at one place and have it work perfectly as the ink level goes from full to nearly empty. If there are any air bubbles in the line, the pen will stop inking. Catch this quickly or the ink will dry in the pen, it needs the ink to move through it to keep itself clean. Just do the tissue, plug and squeeze routine to get it started again. If the pen is skipping it is telling you that something is wrong and you should check ink bottle-height, use a tissue to see if ink will flow, and check ink level in bottle. NEVER let the ink get below the bottom of the tube down into the bottle! If it does, you go back to square one! I drew a big line on my bottle at about 1/4 and that is my signal to re-ink. I occasionally get a line that is too wide. Ink bottle too high can cause this, just move bottle down.. In the Summer when dust blows in, the pen will pick it up and also give a wide trace.

Procedure- I change paper about every three days. I have a micro-switch that will turn the drum drive motor off at the end of the travel and I frequently get an inkblot on the end of the trace. While ugly and data is lost, this is good for the pen as it keeps the ink flowing until you can change paper. When I change paper I gently clean the pen tip with a tissue wiping-off the bit of ink that has dried there and check ink level in the bottle and refill as necessary. I can usually go a week or 10 days before refilling. When finished refilling I hold the syringe vertical and aim it at a piece of tissue and pump air in and out a few times to try to get all the ink out. Shaking and repeating also will get some additional ink out of the syringe (don't do this over carpets!).  If I go on a trip for up to a week, I do nothing. if I am away longer I will remove all ink from the system (by squeezing the bottle), wash in clean distilled water, blow it dry and store in a safe place.

These procedures have worked for me for years and may be useful to you too.

George



At 08:14 PM 10/26/2009, you wrote:
Hello again George.  I forgot to ask how do you get the ink to start flowing.  I noticed that the cap to the ink bottle has what appears as two openings, one for the capillary tubing and a larger open one.  Is the larger one for some type of rubber bulb to force the ink to start flowing through the capillary tubing?
James Allen


George Bush
Sea Ranch, CA, USA
38.73775N, 123.48882W Subject: Re: TELEDYNE-GEOTECH HELICORDER Ink Pen From: Jan Froom JDarwin@............. Date: Tue, 27 Oct 2009 13:52:53 -0700 You want capillary attraction to pull the ink out of the ink reservoir, so you have to have the top of the ink in the reservoir below the pen level, otherwise the ink will siphon causing a very wide inky trace. I use a simple plastic one oz bottle which I've placed two brass tubes in the lid, one going to the bottom of the bottle and one just though the top for a air vent. The one going to the bottom of the bottle is then connected to the pen using neoprene tubing. To get the whole thing going... I put my finger over the air vent tube, squeeze the bottle until ink comes out the pen, then remove my finger from the air vent, and release the squeeze on the bottle. The pen opening must be _*EXACTLY*_ tangent to the face of the drum... I installed the pen... and then put a very fine sand paper on the drum surface and sanded the pen to get that tangent fit. Getting the pen to pull ink was the hardest part of my installation and I probably spent more time getting the pen to work... than anything else. Having George Bush & Steve Hammond available for suggestions and support was the only way I got mine going. Another interesting point is the force at which the pen makes contact with the paper... our pens have a counter weight on a screw at the back end of the pen which can be adjusted to adjust the contact force. Too light and pen will skip on a large rapid swings... too heavy and you've decreased your sensitivity. I'm curious as to how many other "drummers" are out there? Jan in Gilroy Stephen Hammond wrote: > > Hi, the ink will flow if the reservoir fluid level is above the pen. > The trick is to keep it from flowing too much. I used a wire clamp on > the tubing to cut the flow down. Professional models used low pressure > pumps and an fin valve. If I can suggest, search online for "chart pen > ink" and you will find the Recorder Charts Pens Company in Newhall CA. > 800-758-0740. While they do not list your unit they have a large > selection of professional pens, ink and paper. It might be worth a > trip to the website or even a call to see what they can offer in the > way of a solution. > > Steve > > > > *From:* psn-l-request@.............. > [mailto:psn-l-request@............... *On Behalf Of *James Allen > *Sent:* Saturday, October 24, 2009 9:46 PM > *To:* psn-l@.............. > *Subject:* Re: TELEDYNE-GEOTECH HELICORDER > > > > Steve Hammond > > Is there need for a special reservoir to insert the capillary tubing > into or will the ink start flowing by the action of the pen on the > chart paper? > > Thanks > > James Allen > > ----- Original Message ----- > > *From:* Stephen Hammond > > *To:* psn-l@.............. > > *Sent:* Saturday, October 24, 2009 8:41 PM > > *Subject:* RE: TELEDYNE-GEOTECH HELICORDER > > > > There is a typo. Not needs try needle... Steve > > > > *From:* psn-l-request@.............. > > [mailto:psn-l-request@............... *On Behalf Of *Stephen Hammond > *Sent:* Saturday, October 24, 2009 8:38 PM > *To:* psn-l@.............. > *Subject:* RE: TELEDYNE-GEOTECH HELICORDER > > > > For some time some PSN members were using hypodermic needs to > build ink pens. You simply grind the point off and have a > precession tip that can then be connected to the reservoir using > a capillary feed tube. We learned the process from Howard who used > this design back in the first Bay area seismic station way before > our time in the 40's. I ran two drum recorders back around 1990 > and Jan Froom currently has a display station at Bonfante Gardens > in Gilroy CA that has a permanent display he put together for > them also using this design. > > Regards, Steve Hammond PSN Aptos, CA > > > > > You want capillary attraction to pull the ink out of the ink reservoir, so you have to have the top of the ink in the reservoir below the pen level, otherwise the ink will siphon causing a very wide inky trace.  
I use a simple plastic one oz bottle which I've placed two brass tubes in the lid, one going to the bottom of the
bottle and one just though the top for a air vent. The one going to the bottom of the bottle is then connected to the pen using
neoprene tubing. To get the whole thing going... I put my finger over the air vent tube, squeeze the bottle until ink comes out
the pen, then remove my finger from the air vent, and release the squeeze on the bottle.
The pen opening must be EXACTLY tangent to the face of the drum... I installed the pen... and then put a very fine sand
paper on the drum surface and sanded the pen to get that tangent fit.

Getting the pen to pull ink was the hardest part of my installation and
I probably spent more time getting the pen to work... than anything else. 
Having George Bush & Steve Hammond available for suggestions and support was the only way I got mine going.

Another interesting point is the force at which the pen makes contact with the paper...
our pens have a counter weight on a screw at the back end of the pen which can be adjusted to adjust the contact force.
Too light and pen will skip on a large rapid swings... too heavy and you've decreased your sensitivity.

I'm curious as to how many other "drummers" are out there?

Jan in Gilroy

Stephen Hammond wrote:

Hi, the ink will flow if the reservoir fluid level is above the pen. The trick is to keep it from flowing too much. I used a wire clamp on the tubing to cut the flow down. Professional models used low pressure pumps and an fin valve. If I can suggest, search online for “chart pen ink” and you will find the Recorder Charts Pens Company in Newhall CA. 800-758-0740. While they do not list your unit they have a large selection of professional pens, ink and paper. It might be worth a trip to the website or even a call to see what they can offer in the way of a solution.

Steve

 

From: psn-l-request@.............. [mailto:psn-l-request@..............] On Behalf Of James Allen
Sent: Saturday, October 24, 2009 9:46 PM
To: psn-l@..............
Subject: Re: TELEDYNE-GEOTECH HELICORDER

 

Steve Hammond

Is there need for a special reservoir to insert the capillary tubing into or will the ink start flowing by the action of the pen on the chart paper?

Thanks

James Allen

----- Original Message -----

Sent: Saturday, October 24, 2009 8:41 PM

Subject: RE: TELEDYNE-GEOTECH HELICORDER

 

There is a typo. Not needs try needle… Steve

 

From: psn-l-request@.............. [mailto:psn-l-request@..............] On Behalf Of Stephen Hammond
Sent: Saturday, October 24, 2009 8:38 PM
To: psn-l@..............
Subject: RE: TELEDYNE-GEOTECH HELICORDER

 

For some time some PSN members were using hypodermic needs to build ink pens. You simply grind the point off and have a precession tip that  can then be connected to the reservoir using a capillary feed tube. We learned the process from Howard who used this design back in the first Bay area seismic station way before our time in the 40’s. I ran two drum recorders back around 1990 and Jan Froom currently has a display station at Bonfante Gardens  in Gilroy CA that has a permanent display he put together for them also using this design.

Regards, Steve Hammond PSN Aptos, CA

 

 

Subject: Re: TELEDYNE-GEOTECH HELICORDER Ink Pen From: "Geoffrey" gmvoeth@........... Date: Wed, 28 Oct 2009 07:36:32 -0700 For a lot less trouble why not simply get A wide screen LED TV and a LAPTOP ? I bet they may even be less expensive than those drum recorders ? Capillary action sounds like the trees use to pick up water from their roots ??? I think the pumping is really caused by the outflow (EVAPORATION OR ? MOVING PAPER) pulling up on the reservoir as the ink goes to the paper. The capillary action only keeps the ink in the tube and little more. INTERESTING, never thought of this before. You guys need to study plant roots & Leaves to understand your own equipment. ----- Original Message ----- From: "Jan Froom" To: Sent: Tuesday, October 27, 2009 1:52 PM Subject: Re: TELEDYNE-GEOTECH HELICORDER Ink Pen > You want capillary attraction to pull the ink out of the ink reservoir, > so you have to have the top of the ink in the reservoir below the pen > level, otherwise the ink will siphon causing a very wide inky trace. > I use a simple plastic one oz bottle which I've placed two brass tubes > in the lid, one going to the bottom of the > bottle and one just though the top for a air vent. The one going to the > bottom of the bottle is then connected to the pen using > neoprene tubing. To get the whole thing going... I put my finger over > the air vent tube, squeeze the bottle until ink comes out > the pen, then remove my finger from the air vent, and release the > squeeze on the bottle. > The pen opening must be _*EXACTLY*_ tangent to the face of the drum... I > installed the pen... and then put a very fine sand > paper on the drum surface and sanded the pen to get that tangent fit. > > Getting the pen to pull ink was the hardest part of my installation and > I probably spent more time getting the pen to work... than anything else. > Having George Bush & Steve Hammond available for suggestions and support > was the only way I got mine going. > > Another interesting point is the force at which the pen makes contact > with the paper... > our pens have a counter weight on a screw at the back end of the pen > which can be adjusted to adjust the contact force. > Too light and pen will skip on a large rapid swings... too heavy and > you've decreased your sensitivity. > > I'm curious as to how many other "drummers" are out there? > > Jan in Gilroy > > Stephen Hammond wrote: >> >> Hi, the ink will flow if the reservoir fluid level is above the pen. >> The trick is to keep it from flowing too much. I used a wire clamp on >> the tubing to cut the flow down. Professional models used low pressure >> pumps and an fin valve. If I can suggest, search online for "chart pen >> ink" and you will find the Recorder Charts Pens Company in Newhall CA. >> 800-758-0740. While they do not list your unit they have a large >> selection of professional pens, ink and paper. It might be worth a >> trip to the website or even a call to see what they can offer in the >> way of a solution. >> >> Steve >> >> >> >> *From:* psn-l-request@.............. >> [mailto:psn-l-request@............... *On Behalf Of *James Allen >> *Sent:* Saturday, October 24, 2009 9:46 PM >> *To:* psn-l@.............. >> *Subject:* Re: TELEDYNE-GEOTECH HELICORDER >> >> >> >> Steve Hammond >> >> Is there need for a special reservoir to insert the capillary tubing >> into or will the ink start flowing by the action of the pen on the >> chart paper? >> >> Thanks >> >> James Allen >> >> ----- Original Message ----- >> >> *From:* Stephen Hammond >> >> *To:* psn-l@.............. >> >> *Sent:* Saturday, October 24, 2009 8:41 PM >> >> *Subject:* RE: TELEDYNE-GEOTECH HELICORDER >> >> >> >> There is a typo. Not needs try needle... Steve >> >> >> >> *From:* psn-l-request@.............. >> >> [mailto:psn-l-request@............... *On Behalf Of *Stephen Hammond >> *Sent:* Saturday, October 24, 2009 8:38 PM >> *To:* psn-l@.............. >> *Subject:* RE: TELEDYNE-GEOTECH HELICORDER >> >> >> >> For some time some PSN members were using hypodermic needs to >> build ink pens. You simply grind the point off and have a >> precession tip that can then be connected to the reservoir using >> a capillary feed tube. We learned the process from Howard who used >> this design back in the first Bay area seismic station way before >> our time in the 40's. I ran two drum recorders back around 1990 >> and Jan Froom currently has a display station at Bonfante Gardens >> in Gilroy CA that has a permanent display he put together for >> them also using this design. >> >> Regards, Steve Hammond PSN Aptos, CA >> >> >> >> >> > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: microscisms From: Thomas Dick dickthomas01@............. Date: Wed, 28 Oct 2009 10:31:46 -0500 Anybody still getting the 5 sec period wave peaks that started around the 23d of this month and pretty well have been consistant since then? __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: microscisms From: Larry Conklin lconklin@............ Date: Wed, 28 Oct 2009 12:03:39 -0400 I for one, am getting a pretty high level, especially in the last 18 hours or so. I have a little web page that I keep updated with "yesterday's" drum report. http://home.roadrunner.com/~lwconklin/ Bad as it looks now, I've seen much worse. The micorseism noise is typically a lot stronger in the fall/winter months. Larry Conklin Liverpool, NY Thomas Dick wrote: > Anybody still getting the 5 sec period wave peaks that started around > the 23d of this month and pretty well have been consistant since then? > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with the body of > the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: WINQUAKE QUESTION ABOUT HEADER INFO From: "Geoffrey" gmvoeth@........... Date: Thu, 29 Oct 2009 03:45:28 -0700 Hello Folks; Please bear with me here I know you do not like to hear this but it will help me decide how to finish my program. I am rewriting my recording and display programs to use 12 bits instead of 8 to avoid saturation problems. In my display program I create a PSN4 file to be able to read times in winquake and share with the rest of you. I am having problems getting WINQUAKE to properly show the time of the very first sample since MY first sample can be something OTHER than an exact second and usually has a fraction. There are two Items in the header that affect time readings And I'm wondering how to properly use them. WINQUAKE TYPE4 HEADER DATA GIVEN: FIRST SAMPLE TIME 00:00:35.151 Hour? == 00 byte value 0 to 23 Minute? == 00 byte value 0 to 59 Seconds? == 35 byte value 0 to 59 SPACE HOLDER? byte value 0 NANOseconds& LONG signed integer value 4 bytes low endean 0 to 999,999,999 OFFSETseconds# DOUBLE floating point value 8 bytes IEEE Find: What is the proper way to indicate the fractional value which remains ? A. Put the fraction 0.151 into the nanoseconds variable times one billion B. Put the fraction 0.151 into the offset area following the nanoseconds area C. CROP the recorded DATA to start at an exact second D. THERE IS NO WAY TO GET THE FIRST SAMPLE TO SHOW THE PROPER FRACTIONAL VALUE What's the best answer here ? I know if I crop the file to an exact cal mark second I get pretty good fractional times. I am guessing this may be the best way to go since I may be using WQ in ways it was not designed to be used. This will mean saving 4 minutes of modulo history instead of three. I do not want to do this unless absolutely necessary. When I look at my own data I will assign discreet date-times UTC to each sample relative to a given calibration mark and not guess between samples. The cal sample happens at the transition between second 59 and second zero the first sample after this event and I call that the exact second and calculate all other sample times from that one reference point. WINQUAKE works different, possibly better, I just need to understand it better. The times I use are in the WINQUAKE "?" type relating to synchronization with WWV radio broadcast. Thanks for answers, geoff ps, I have found lots of errors in my older program leading to not so good time readings in the past. Every time I do this, the results seem better than before. But now I'm reaching the point of diminishing returns. __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: microscisms From: Thomas Dick dickthomas01@............. Date: Thu, 29 Oct 2009 08:08:19 -0500 > I for one, am getting a pretty high level, especially in the last 18 > hours or so. I have a little web page that I keep updated with > "yesterday's" drum report. Sometime during the night things quieted down here and I got a decent record on the Veracruz quake. Did you have the same experience? __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: microscisms From: Larry Conklin lconklin@............ Date: Thu, 29 Oct 2009 09:56:26 -0400 Hi Tom, Yes, I think the noise level is getting a little better, but it is still fairly strong here. I did manage to see the Veracruz event, but it's pretty well down in the noise and not very impressive. I noticed that I didn't include the URL for my web page in my last answer: http://home.roadrunner.com/~lwconklin/ Also, I routinely monitor the Lamnot-Doherty 24hr drum report at http://www.ldeo.columbia.edu/cgi-bin/LCSN/WebSeis/24hr_heli.pl They are fairly close to me (couple of hundred miles) and it's interesting to compare what they're getting to what I can see. I have a long way to go before I get to the point that I can see everything that they do. Larry Thomas Dick wrote: > >> I for one, am getting a pretty high level, especially in the last 18 >> hours or so. I have a little web page that I keep updated with >> "yesterday's" drum report. > > Sometime during the night things quieted down here and I got a decent > record on the Veracruz quake. Did you have the same experience? > __________________________________________________________ __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: TELEDYNE-GEOTECH HELICORDER Ink Pen From: "James Allen" jcallen1@........... Date: Thu, 29 Oct 2009 08:29:45 -0700 Good point made by Geoffrey regarding why not simply get a wide screen LED TV and a LAPTOP. I am half way there with my large format computer screen. But it is somewhat fun and certainly challenging to try to make the old stuff work. However, after receiving tremendous and detailed information from Jan, George, Chris, Meredith and Steve as well as others on the list it is clear to me at my limited stage of development that converting my drum from thermal to ink would be a very trying experience. I really appreciate the thoughts and experience of you fine folks on this list which is invaluable to a neophyte like me. James Allen ----- Original Message ----- From: "Geoffrey" To: "PSN-LIST" Sent: Wednesday, October 28, 2009 7:36 AM Subject: Re: TELEDYNE-GEOTECH HELICORDER Ink Pen > For a lot less trouble why not simply get > A wide screen LED TV and a LAPTOP ? > > I bet they may even be less expensive > than those drum recorders ? > > Capillary action sounds like the > trees use to pick up water from their roots > ??? > I think the pumping is really caused by > the outflow (EVAPORATION OR ? MOVING PAPER) > pulling up on the reservoir > as the ink goes to the paper. > The capillary action only keeps > the ink in the tube and little more. > > INTERESTING, never thought of this before. > > > You guys need to study plant roots & Leaves > to understand your own equipment. > > > ----- Original Message ----- > From: "Jan Froom" > To: > Sent: Tuesday, October 27, 2009 1:52 PM > Subject: Re: TELEDYNE-GEOTECH HELICORDER Ink Pen > > >> You want capillary attraction to pull the ink out of the ink reservoir, >> so you have to have the top of the ink in the reservoir below the pen >> level, otherwise the ink will siphon causing a very wide inky trace. I >> use a simple plastic one oz bottle which I've placed two brass tubes in >> the lid, one going to the bottom of the >> bottle and one just though the top for a air vent. The one going to the >> bottom of the bottle is then connected to the pen using >> neoprene tubing. To get the whole thing going... I put my finger over the >> air vent tube, squeeze the bottle until ink comes out >> the pen, then remove my finger from the air vent, and release the squeeze >> on the bottle. >> The pen opening must be _*EXACTLY*_ tangent to the face of the drum... I >> installed the pen... and then put a very fine sand >> paper on the drum surface and sanded the pen to get that tangent fit. >> >> Getting the pen to pull ink was the hardest part of my installation and >> I probably spent more time getting the pen to work... than anything else. >> Having George Bush & Steve Hammond available for suggestions and support >> was the only way I got mine going. >> >> Another interesting point is the force at which the pen makes contact >> with the paper... >> our pens have a counter weight on a screw at the back end of the pen >> which can be adjusted to adjust the contact force. >> Too light and pen will skip on a large rapid swings... too heavy and >> you've decreased your sensitivity. >> >> I'm curious as to how many other "drummers" are out there? >> >> Jan in Gilroy >> >> Stephen Hammond wrote: >>> >>> Hi, the ink will flow if the reservoir fluid level is above the pen. The >>> trick is to keep it from flowing too much. I used a wire clamp on the >>> tubing to cut the flow down. Professional models used low pressure pumps >>> and an fin valve. If I can suggest, search online for "chart pen ink" >>> and you will find the Recorder Charts Pens Company in Newhall CA. >>> 800-758-0740. While they do not list your unit they have a large >>> selection of professional pens, ink and paper. It might be worth a trip >>> to the website or even a call to see what they can offer in the way of a >>> solution. >>> >>> Steve >>> >>> >>> *From:* psn-l-request@.............. >>> [mailto:psn-l-request@............... *On Behalf Of *James Allen >>> *Sent:* Saturday, October 24, 2009 9:46 PM >>> *To:* psn-l@.............. >>> *Subject:* Re: TELEDYNE-GEOTECH HELICORDER >>> >>> >>> Steve Hammond >>> >>> Is there need for a special reservoir to insert the capillary tubing >>> into or will the ink start flowing by the action of the pen on the chart >>> paper? >>> >>> Thanks >>> >>> James Allen >>> >>> ----- Original Message ----- >>> >>> *From:* Stephen Hammond >>> >>> *To:* psn-l@.............. >>> >>> *Sent:* Saturday, October 24, 2009 8:41 PM >>> >>> *Subject:* RE: TELEDYNE-GEOTECH HELICORDER >>> >>> >>> There is a typo. Not needs try needle... Steve >>> >>> >>> *From:* psn-l-request@.............. >>> >>> [mailto:psn-l-request@............... *On Behalf Of *Stephen Hammond >>> *Sent:* Saturday, October 24, 2009 8:38 PM >>> *To:* psn-l@.............. >>> *Subject:* RE: TELEDYNE-GEOTECH HELICORDER >>> >>> >>> For some time some PSN members were using hypodermic needs to >>> build ink pens. You simply grind the point off and have a >>> precession tip that can then be connected to the reservoir using >>> a capillary feed tube. We learned the process from Howard who used >>> this design back in the first Bay area seismic station way before >>> our time in the 40's. I ran two drum recorders back around 1990 >>> and Jan Froom currently has a display station at Bonfante Gardens >>> in Gilroy CA that has a permanent display he put together for >>> them also using this design. >>> >>> Regards, Steve Hammond PSN Aptos, CA >>> >>> >>> >> > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with the body of the > message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: microscisms From: Thomas Dick dickthomas01@............. Date: Thu, 29 Oct 2009 20:11:25 -0500 Larry > > > > I noticed that I didn't include the URL for my web page in my last > answer: > > http://home.roadrunner.com/~lwconklin/ > > Also, I routinely monitor the Lamnot-Doherty 24hr drum report at > > http://www.ldeo.columbia.edu/cgi-bin/LCSN/WebSeis/24hr_heli.pl > > They are fairly close to me (couple of hundred miles) and it's > interesting to compare what they're getting to what I can see. I have > a long way to go before I get to the point that I can see everything > that they do. I have been on the Lamnot-Doherty site several times. I am fortunate to have three good sites near me (one less than 20 miles - University of Southern Indiana and the other two less than 70 miles - Wyandotte Cave and Indiana University). __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: HELICORDER value From: George Bush ke6pxp@....... Date: Sat, 31 Oct 2009 09:27:08 -0700 Hi Geoffrey and James- I don't think it is an either/or question. I have both and am delighted with what I get on the drum and what I get on the computer. The computer lets me analyze the trace, upload it to the PSN server for all to see, lets me put a 24-hour trace on my website (http://gbush.mcn.org/srn.gif) where it is available for friends and for me to see anywhere in my house on my laptop and wireless connection. With the drum recorder I am preserving a bit of history and the drum is what impresses visitors. It is also my warning signal as it sits in our living room and you can hear the pen skritching on the paper when the quake comes in. To me, nothing beats the WOW-factor of watching a world-class quake come in on a drum recorder. George At 07:36 AM 10/28/2009, you wrote: >For a lot less trouble why not simply get >A wide screen LED TV and a LAPTOP ? > >I bet they may even be less expensive >than those drum recorders ? > >Capillary action sounds like the >trees use to pick up water from their roots >??? >I think the pumping is really caused by >the outflow (EVAPORATION OR ? MOVING PAPER) >pulling up on the reservoir >as the ink goes to the paper. >The capillary action only keeps >the ink in the tube and little more. > >INTERESTING, never thought of this before. > > >You guys need to study plant roots & Leaves >to understand your own equipment. > > >----- Original Message ----- From: "Jan Froom" >To: >Sent: Tuesday, October 27, 2009 1:52 PM >Subject: Re: TELEDYNE-GEOTECH HELICORDER Ink Pen > > >>You want capillary attraction to pull the ink out of the ink >>reservoir, so you have to have the top of the ink in the reservoir >>below the pen level, otherwise the ink will siphon causing a very >>wide inky trace. >>I use a simple plastic one oz bottle which I've placed two brass >>tubes in the lid, one going to the bottom of the >>bottle and one just though the top for a air vent. The one going to >>the bottom of the bottle is then connected to the pen using >>neoprene tubing. To get the whole thing going... I put my finger >>over the air vent tube, squeeze the bottle until ink comes out >>the pen, then remove my finger from the air vent, and release the >>squeeze on the bottle. >>The pen opening must be _*EXACTLY*_ tangent to the face of the >>drum... I installed the pen... and then put a very fine sand >>paper on the drum surface and sanded the pen to get that tangent fit. >>Getting the pen to pull ink was the hardest part of my installation and >>I probably spent more time getting the pen to work... than anything >>else. Having George Bush & Steve Hammond available for suggestions >>and support was the only way I got mine going. >>Another interesting point is the force at which the pen makes >>contact with the paper... >>our pens have a counter weight on a screw at the back end of the >>pen which can be adjusted to adjust the contact force. >>Too light and pen will skip on a large rapid swings... too heavy >>and you've decreased your sensitivity. >>I'm curious as to how many other "drummers" are out there? >>Jan in Gilroy >>Stephen Hammond wrote: >>> >>>Hi, the ink will flow if the reservoir fluid level is above the >>>pen. The trick is to keep it from flowing too much. I used a wire >>>clamp on the tubing to cut the flow down. Professional models used >>>low pressure pumps and an fin valve. If I can suggest, search >>>online for "chart pen ink" and you will find the Recorder Charts >>>Pens Company in Newhall CA. 800-758-0740. While they do not list >>>your unit they have a large selection of professional pens, ink >>>and paper. It might be worth a trip to the website or even a call >>>to see what they can offer in the way of a solution. >>> >>>Steve >>> >>> >>> >>>*From:* psn-l-request@.............. >>>[mailto:psn-l-request@............... *On Behalf Of *James Allen >>>*Sent:* Saturday, October 24, 2009 9:46 PM >>>*To:* psn-l@.............. >>>*Subject:* Re: TELEDYNE-GEOTECH HELICORDER >>> >>> >>> >>>Steve Hammond >>> >>>Is there need for a special reservoir to insert the capillary >>>tubing into or will the ink start flowing by the action of the pen >>>on the chart paper? >>> >>>Thanks >>> >>>James Allen >>> >>> ----- Original Message ----- >>> >>> *From:* Stephen Hammond >>> >>> *To:* psn-l@.............. >>> >>> *Sent:* Saturday, October 24, 2009 8:41 PM >>> >>> *Subject:* RE: TELEDYNE-GEOTECH HELICORDER >>> >>> >>> >>> There is a typo. Not needs try needle... Steve >>> >>> >>> >>> *From:* psn-l-request@.............. >>> >>> [mailto:psn-l-request@............... *On Behalf Of *Stephen Hammond >>> *Sent:* Saturday, October 24, 2009 8:38 PM >>> *To:* psn-l@.............. >>> *Subject:* RE: TELEDYNE-GEOTECH HELICORDER >>> >>> >>> >>> For some time some PSN members were using hypodermic needs to >>> build ink pens. You simply grind the point off and have a >>> precession tip that can then be connected to the reservoir using >>> a capillary feed tube. We learned the process from Howard who used >>> this design back in the first Bay area seismic station way before >>> our time in the 40's. I ran two drum recorders back around 1990 >>> and Jan Froom currently has a display station at Bonfante Gardens >>> in Gilroy CA that has a permanent display he put together for >>> them also using this design. >>> >>> Regards, Steve Hammond PSN Aptos, CA >>> >>> >>> >>> >__________________________________________________________ > >Public Seismic Network Mailing List (PSN-L) > >To leave this list email PSN-L-REQUEST@.............. with the body >of the message (first line only): unsubscribe >See http://www.seismicnet.com/maillist.html for more information. George Bush Sea Ranch, CA, USA 38.73775N, 123.48882W Hi Geoffrey  and James-

I don't think it is an either/or question. I have both and am delighted with what I get on the drum and what I get on the computer.

The computer lets me analyze the trace, upload it to the PSN server for all to see, lets me put a 24-hour trace on my website (http://gbush.mcn.org/srn.gif) where it is available for friends and for me to see anywhere in my house on my laptop and wireless connection.

With the drum recorder I am preserving a bit of history and the drum is what impresses visitors. It is also my warning signal as it sits in our living room and you can hear the pen skritching on the paper when the quake comes in. To me, nothing beats the WOW-factor of watching a world-class quake come in on a drum recorder.

George


At 07:36 AM 10/28/2009, you wrote:
For a lot less trouble why not simply get
A wide screen LED TV and a LAPTOP ?

I bet they may even be less expensive
than those drum recorders ?

Capillary action sounds like the
trees use to pick up water from their roots
???
I think the pumping is really caused by
the outflow (EVAPORATION OR ? MOVING PAPER)
pulling up on the reservoir
as the ink goes to the paper.
The capillary action only keeps
the ink in the tube and little more.

INTERESTING, never thought of this before.


You guys need to study plant roots & Leaves
to understand your own equipment.


----- Original Message ----- From: "Jan Froom" <JDarwin@.............>
To: <psn-l@..............>
Sent: Tuesday, October 27, 2009 1:52 PM
Subject: Re: TELEDYNE-GEOTECH HELICORDER Ink Pen


You want capillary attraction to pull the ink out of the ink reservoir, so you have to have the top of the ink in the reservoir below the pen level, otherwise the ink will siphon causing a very wide inky trace. 
I use a simple plastic one oz bottle which I've placed two brass tubes in the lid, one going to the bottom of the
bottle and one just though the top for a air vent. The one going to the bottom of the bottle is then connected to the pen using
neoprene tubing. To get the whole thing going... I put my finger over the air vent tube, squeeze the bottle until ink comes out
the pen, then remove my finger from the air vent, and release the squeeze on the bottle.
The pen opening must be _*EXACTLY*_ tangent to the face of the drum... I installed the pen... and then put a very fine sand
paper on the drum surface and sanded the pen to get that tangent fit.
Getting the pen to pull ink was the hardest part of my installation and
I probably spent more time getting the pen to work... than anything else. Having George Bush & Steve Hammond available for suggestions and support was the only way I got mine going.
Another interesting point is the force at which the pen makes contact with the paper...
our pens have a counter weight on a screw at the back end of the pen which can be adjusted to adjust the contact force.
Too light and pen will skip on a large rapid swings... too heavy and you've decreased your sensitivity.
I'm curious as to how many other "drummers" are out there?
Jan in Gilroy
Stephen Hammond wrote:

Hi, the ink will flow if the reservoir fluid level is above the pen. The trick is to keep it from flowing too much. I used a wire clamp on the tubing to cut the flow down. Professional models used low pressure pumps and an fin valve. If I can suggest, search online for "chart pen ink" and you will find the Recorder Charts Pens Company in Newhall CA. 800-758-0740. While they do not list your unit they have a large selection of professional pens, ink and paper. It might be worth a trip to the website or even a call to see what they can offer in the way of a solution.

Steve

 

*From:* psn-l-request@.............. [ mailto:psn-l-request@..............] *On Behalf Of *James Allen
*Sent:* Saturday, October 24, 2009 9:46 PM
*To:* psn-l@..............
*Subject:* Re: TELEDYNE-GEOTECH HELICORDER

 

Steve Hammond

Is there need for a special reservoir to insert the capillary tubing into or will the ink start flowing by the action of the pen on the chart paper?

Thanks

James Allen

    ----- Original Message -----

    *From:* Stephen Hammond < mailto:shammon1@.............>

    *To:* psn-l@.............. < mailto:psn-l@..............>

    *Sent:* Saturday, October 24, 2009 8:41 PM

    *Subject:* RE: TELEDYNE-GEOTECH HELICORDER

    

    There is a typo. Not needs try needle... Steve

    

    *From:* psn-l-request@..............
    < mailto:psn-l-request@..............>
    [ mailto:psn-l-request@..............] *On Behalf Of *Stephen Hammond
    *Sent:* Saturday, October 24, 2009 8:38 PM
    *To:* psn-l@.............. < mailto:psn-l@..............>
    *Subject:* RE: TELEDYNE-GEOTECH HELICORDER

    

    For some time some PSN members were using hypodermic needs to
    build ink pens. You simply grind the point off and have a
    precession tip that  can then be connected to the reservoir using
    a capillary feed tube. We learned the process from Howard who used
    this design back in the first Bay area seismic station way before
    our time in the 40's. I ran two drum recorders back around 1990
    and Jan Froom currently has a display station at Bonfante Gardens
     in Gilroy CA that has a permanent display he put together for
    them also using this design.

    Regards, Steve Hammond PSN Aptos, CA

    

    
__________________________________________________________

Public Seismic Network Mailing List (PSN-L)

http://www.seismicnet.com/maillist.html for more information.


George Bush
Sea Ranch, CA, USA
38.73775N, 123.48882W Subject: Re: HELICORDER value From: "Edward Ianni" edwianni1@........... Date: Sat, 31 Oct 2009 16:28:40 -0100 This is an interesting point. It would be very nice to be alerted = audibly when an event is actually being received (occurring) in one of = our data logging/analysis programs. I assume it's not that easy to do = because of the varying noise and event levels. Ed.=20 With the drum recorder I am preserving a bit of history and the drum = is what impresses visitors. It is also my warning signal as it sits in = our living room and you can hear the pen skritching on the paper when = the quake comes in. To me, nothing beats the WOW-factor of watching a = world-class quake come in on a drum recorder. George At 07:36 AM 10/28/2009, you wrote: For a lot less trouble why not simply get A wide screen LED TV and a LAPTOP ? I bet they may even be less expensive than those drum recorders ? Capillary action sounds like the trees use to pick up water from their roots ??? I think the pumping is really caused by the outflow (EVAPORATION OR ? MOVING PAPER) pulling up on the reservoir as the ink goes to the paper. The capillary action only keeps the ink in the tube and little more. INTERESTING, never thought of this before. You guys need to study plant roots & Leaves to understand your own equipment. ----- Original Message ----- From: "Jan Froom" = To: Sent: Tuesday, October 27, 2009 1:52 PM Subject: Re: TELEDYNE-GEOTECH HELICORDER Ink Pen You want capillary attraction to pull the ink out of the ink = reservoir, so you have to have the top of the ink in the reservoir below = the pen level, otherwise the ink will siphon causing a very wide inky = trace. =20 I use a simple plastic one oz bottle which I've placed two brass = tubes in the lid, one going to the bottom of the bottle and one just though the top for a air vent. The one going = to the bottom of the bottle is then connected to the pen using neoprene tubing. To get the whole thing going... I put my finger = over the air vent tube, squeeze the bottle until ink comes out the pen, then remove my finger from the air vent, and release the = squeeze on the bottle. The pen opening must be _*EXACTLY*_ tangent to the face of the = drum... I installed the pen... and then put a very fine sand paper on the drum surface and sanded the pen to get that tangent = fit. Getting the pen to pull ink was the hardest part of my = installation and I probably spent more time getting the pen to work... than = anything else. Having George Bush & Steve Hammond available for = suggestions and support was the only way I got mine going. Another interesting point is the force at which the pen makes = contact with the paper... our pens have a counter weight on a screw at the back end of the = pen which can be adjusted to adjust the contact force. Too light and pen will skip on a large rapid swings... too heavy = and you've decreased your sensitivity. I'm curious as to how many other "drummers" are out there? Jan in Gilroy Stephen Hammond wrote: Hi, the ink will flow if the reservoir fluid level is above the = pen. The trick is to keep it from flowing too much. I used a wire clamp = on the tubing to cut the flow down. Professional models used low = pressure pumps and an fin valve. If I can suggest, search online for = "chart pen ink" and you will find the Recorder Charts Pens Company in = Newhall CA. 800-758-0740. While they do not list your unit they have a = large selection of professional pens, ink and paper. It might be worth a = trip to the website or even a call to see what they can offer in the way = of a solution. Steve =20 *From:* psn-l-request@.............. [ = mailto:psn-l-request@............... *On Behalf Of *James Allen *Sent:* Saturday, October 24, 2009 9:46 PM *To:* psn-l@.............. *Subject:* Re: TELEDYNE-GEOTECH HELICORDER =20 Steve Hammond Is there need for a special reservoir to insert the capillary = tubing into or will the ink start flowing by the action of the pen on = the chart paper? Thanks James Allen ----- Original Message ----- *From:* Stephen Hammond < mailto:shammon1@.............> *To:* psn-l@.............. < mailto:psn-l@..............> *Sent:* Saturday, October 24, 2009 8:41 PM *Subject:* RE: TELEDYNE-GEOTECH HELICORDER =20 There is a typo. Not needs try needle... Steve =20 *From:* psn-l-request@.............. < mailto:psn-l-request@..............> [ mailto:psn-l-request@............... *On Behalf Of = *Stephen Hammond *Sent:* Saturday, October 24, 2009 8:38 PM *To:* psn-l@.............. < mailto:psn-l@..............> *Subject:* RE: TELEDYNE-GEOTECH HELICORDER =20 For some time some PSN members were using hypodermic needs = to build ink pens. You simply grind the point off and have a precession tip that can then be connected to the reservoir = using a capillary feed tube. We learned the process from Howard = who used this design back in the first Bay area seismic station way = before our time in the 40's. I ran two drum recorders back around = 1990 and Jan Froom currently has a display station at Bonfante = Gardens in Gilroy CA that has a permanent display he put together = for them also using this design. Regards, Steve Hammond PSN Aptos, CA =20 =20 __________________________________________________________ Public Seismic Network Mailing List (PSN-L) To leave this list email PSN-L-REQUEST@.............. with the body = of the message (first line only): unsubscribe See http://www.seismicnet.com/maillist.html for more information. George Bush Sea Ranch, CA, USA 38.73775N, 123.48882W=20 -------------------------------------------------------------------------= ----- No virus found in this incoming message. Checked by AVG - www.avg.com=20 Version: 8.5.423 / Virus Database: 270.14.40/2471 - Release Date: = 10/31/09 07:53:00

This is an interesting point. It would = be very nice=20 to be alerted audibly when an event is actually being received = (occurring)=20 in one of our data logging/analysis programs. I assume it's not = that easy=20 to do because of the varying noise and event levels.  =20 Ed. 

With the drum recorder I am = preserving a bit of=20 history and the drum is what impresses visitors. It is also my warning = signal=20 as it sits in our living room and you can hear the pen skritching on = the paper=20 when the quake comes in. To me, nothing beats the WOW-factor of = watching a=20 world-class quake come in on a drum = recorder.

George


At=20 07:36 AM 10/28/2009, you wrote:
For a lot less = trouble why not=20 simply get
A wide screen LED TV and a LAPTOP ?

I bet they = may even=20 be less expensive
than those drum recorders ?

Capillary = action=20 sounds like the
trees use to pick up water from their = roots
???
I=20 think the pumping is really caused by
the outflow (EVAPORATION OR = ?=20 MOVING PAPER)
pulling up on the reservoir
as the ink goes to = the=20 paper.
The capillary action only keeps
the ink in the tube and = little=20 more.

INTERESTING, never thought of this = before.


You guys=20 need to study plant roots & Leaves
to understand your own=20 equipment.


----- Original Message ----- From: "Jan Froom" = <JDarwin@.............>
To: = <psn-l@..............>
Sent:=20 Tuesday, October 27, 2009 1:52 PM
Subject: Re: TELEDYNE-GEOTECH=20 HELICORDER Ink Pen


You want capillary = attraction=20 to pull the ink out of the ink reservoir, so you have to have the = top of=20 the ink in the reservoir below the pen level, otherwise the ink = will=20 siphon causing a very wide inky trace. 
I use a simple = plastic=20 one oz bottle which I've placed two brass tubes in the lid, one = going to=20 the bottom of the
bottle and one just though the top for a air = vent.=20 The one going to the bottom of the bottle is then connected to the = pen=20 using
neoprene tubing. To get the whole thing going... I put my = finger=20 over the air vent tube, squeeze the bottle until ink comes = out
the pen,=20 then remove my finger from the air vent, and release the squeeze = on the=20 bottle.
The pen opening must be _*EXACTLY*_ tangent to the face = of the=20 drum... I installed the pen... and then put a very fine = sand
paper on=20 the drum surface and sanded the pen to get that tangent = fit.
Getting=20 the pen to pull ink was the hardest part of my installation = and
I=20 probably spent more time getting the pen to work... than anything = else.=20 Having George Bush & Steve Hammond available for suggestions = and=20 support was the only way I got mine going.
Another interesting = point is=20 the force at which the pen makes contact with the paper...
our = pens=20 have a counter weight on a screw at the back end of the pen which = can be=20 adjusted to adjust the contact force.
Too light and pen will = skip on a=20 large rapid swings... too heavy and you've decreased your=20 sensitivity.
I'm curious as to how many other "drummers" are = out=20 there?
Jan in Gilroy
Stephen Hammond wrote:

Hi, the ink = will flow if=20 the reservoir fluid level is above the pen. The trick is to keep = it from=20 flowing too much. I used a wire clamp on the tubing to cut the = flow=20 down. Professional models used low pressure pumps and an fin = valve. If I=20 can suggest, search online for "chart pen ink" and you will find = the=20 Recorder Charts Pens Company in Newhall CA. 800-758-0740. While = they do=20 not list your unit they have a large selection of professional = pens, ink=20 and paper. It might be worth a trip to the website or even a = call to see=20 what they can offer in the way of a=20 solution.

Steve

 

*From:*=20 psn-l-request@.............. [ = mailto:psn-l-request@..............] *On Behalf Of *James=20 Allen
*Sent:* Saturday, October 24, 2009 9:46 PM
*To:*=20 psn-l@..............
*Subject:* Re: TELEDYNE-GEOTECH=20 HELICORDER

 

Steve Hammond

Is there = need for a=20 special reservoir to insert the capillary tubing into or will = the ink=20 start flowing by the action of the pen on the chart=20 paper?

Thanks

James = Allen

    -----=20 Original Message -----

    *From:* Stephen = Hammond=20 <=20 mailto:shammon1@.............>

    = *To:*=20 psn-l@.............. <=20 mailto:psn-l@..............>

    = *Sent:*=20 Saturday, October 24, 2009 8:41 PM

    = *Subject:*=20 RE: TELEDYNE-GEOTECH HELICORDER

    =20

    There is a typo. Not needs try = needle...=20 Steve

    

    = *From:*=20 psn-l-request@..............
    < = = mailto:psn-l-request@..............>
    [ = mailto:psn-l-request@..............] *On Behalf Of *Stephen=20 Hammond
    *Sent:* Saturday, October 24, 2009 = 8:38=20 PM
    *To:* psn-l@.............. <=20 mailto:psn-l@..............>
    = *Subject:* RE:=20 TELEDYNE-GEOTECH HELICORDER

    =20

    For some time some PSN members were = using=20 hypodermic needs to
    build ink pens. You = simply=20 grind the point off and have a
    precession = tip=20 that  can then be connected to the reservoir=20 using
    a capillary feed tube. We learned = the=20 process from Howard who used
    this design = back in=20 the first Bay area seismic station way = before
    our=20 time in the 40's. I ran two drum recorders back around=20 1990
    and Jan Froom currently has a display = station=20 at Bonfante Gardens
     in Gilroy CA = that has a=20 permanent display he put together for
    them = also=20 using this design.

    Regards, Steve = Hammond PSN=20 Aptos, CA

    =20

    =20 =
___________________________________________= _______________

Public=20 Seismic Network Mailing List (PSN-L)

To leave this list email = PSN-L-REQUEST@.............. with the body of the message (first = line only):=20 unsubscribe
See http://www.seismicnet.com/maillist.html for = more=20 information.


George Bush
Sea Ranch, CA, USA
38.73775N, = 123.48882W=20


No virus found in this incoming message.
Checked by AVG = -=20 www.avg.com
Version: 8.5.423 / Virus Database: 270.14.40/2471 - = Release=20 Date: 10/31/09 07:53:00
Subject: RE: HELICORDER value From: "Gary Lindgren" gel@................. Date: Sat, 31 Oct 2009 10:59:26 -0700 Edward, WinSDR has audible alarms built in the application. Different sounds whether close by or teleseismic events. You just have to make sure you turn the speaker down at night unless you want to wake up because of a heavy freight train going down the track a mile away. Certainly having a paper trace is impressive, but I would worry about maintaining it up all the time. Gary From: psn-l-request@.............. [mailto:psn-l-request@............... On Behalf Of Edward Ianni Sent: Saturday, October 31, 2009 10:29 AM To: psn-l@.............. Subject: Re: HELICORDER value This is an interesting point. It would be very nice to be alerted audibly when an event is actually being received (occurring) in one of our data logging/analysis programs. I assume it's not that easy to do because of the varying noise and event levels. Ed. With the drum recorder I am preserving a bit of history and the drum is what impresses visitors. It is also my warning signal as it sits in our living room and you can hear the pen skritching on the paper when the quake comes in. To me, nothing beats the WOW-factor of watching a world-class quake come in on a drum recorder. George At 07:36 AM 10/28/2009, you wrote: For a lot less trouble why not simply get A wide screen LED TV and a LAPTOP ? I bet they may even be less expensive than those drum recorders ? Capillary action sounds like the trees use to pick up water from their roots ??? I think the pumping is really caused by the outflow (EVAPORATION OR ? MOVING PAPER) pulling up on the reservoir as the ink goes to the paper. The capillary action only keeps the ink in the tube and little more. INTERESTING, never thought of this before. You guys need to study plant roots & Leaves to understand your own equipment. ----- Original Message ----- From: "Jan Froom" To: Sent: Tuesday, October 27, 2009 1:52 PM Subject: Re: TELEDYNE-GEOTECH HELICORDER Ink Pen You want capillary attraction to pull the ink out of the ink reservoir, so you have to have the top of the ink in the reservoir below the pen level, otherwise the ink will siphon causing a very wide inky trace. I use a simple plastic one oz bottle which I've placed two brass tubes in the lid, one going to the bottom of the bottle and one just though the top for a air vent. The one going to the bottom of the bottle is then connected to the pen using neoprene tubing. To get the whole thing going... I put my finger over the air vent tube, squeeze the bottle until ink comes out the pen, then remove my finger from the air vent, and release the squeeze on the bottle. The pen opening must be _*EXACTLY*_ tangent to the face of the drum... I installed the pen... and then put a very fine sand paper on the drum surface and sanded the pen to get that tangent fit. Getting the pen to pull ink was the hardest part of my installation and I probably spent more time getting the pen to work... than anything else. Having George Bush & Steve Hammond available for suggestions and support was the only way I got mine going. Another interesting point is the force at which the pen makes contact with the paper... our pens have a counter weight on a screw at the back end of the pen which can be adjusted to adjust the contact force. Too light and pen will skip on a large rapid swings... too heavy and you've decreased your sensitivity. I'm curious as to how many other "drummers" are out there? Jan in Gilroy Stephen Hammond wrote: Hi, the ink will flow if the reservoir fluid level is above the pen. The trick is to keep it from flowing too much. I used a wire clamp on the tubing to cut the flow down. Professional models used low pressure pumps and an fin valve. If I can suggest, search online for "chart pen ink" and you will find the Recorder Charts Pens Company in Newhall CA. 800-758-0740. While they do not list your unit they have a large selection of professional pens, ink and paper. It might be worth a trip to the website or even a call to see what they can offer in the way of a solution. Steve *From:* psn-l-request@.............. [ mailto:psn-l-request@.............. ] *On Behalf Of *James Allen *Sent:* Saturday, October 24, 2009 9:46 PM *To:* psn-l@.............. *Subject:* Re: TELEDYNE-GEOTECH HELICORDER Steve Hammond Is there need for a special reservoir to insert the capillary tubing into or will the ink start flowing by the action of the pen on the chart paper? Thanks James Allen ----- Original Message ----- *From:* Stephen Hammond < mailto:shammon1@............. > *To:* psn-l@.............. < mailto:psn-l@.............. > *Sent:* Saturday, October 24, 2009 8:41 PM *Subject:* RE: TELEDYNE-GEOTECH HELICORDER There is a typo. Not needs try needle... Steve *From:* psn-l-request@.............. < mailto:psn-l-request@..............> [ mailto:psn-l-request@............... *On Behalf Of *Stephen Hammond *Sent:* Saturday, October 24, 2009 8:38 PM *To:* psn-l@.............. < mailto:psn-l@.............. > *Subject:* RE: TELEDYNE-GEOTECH HELICORDER For some time some PSN members were using hypodermic needs to build ink pens. You simply grind the point off and have a precession tip that can then be connected to the reservoir using a capillary feed tube. We learned the process from Howard who used this design back in the first Bay area seismic station way before our time in the 40's. I ran two drum recorders back around 1990 and Jan Froom currently has a display station at Bonfante Gardens in Gilroy CA that has a permanent display he put together for them also using this design. Regards, Steve Hammond PSN Aptos, CA __________________________________________________________ Public Seismic Network Mailing List (PSN-L) George Bush Sea Ranch, CA, USA 38.73775N, 123.48882W _____ No virus found in this incoming message. Checked by AVG - www.avg.com Version: 8.5.423 / Virus Database: 270.14.40/2471 - Release Date: 10/31/09 07:53:00

Edward,

WinSDR has audible alarms built in the application. = Different sounds whether close by or teleseismic events. You just have to make = sure you turn the speaker down at night unless you want to wake up because of a = heavy freight train going down the track a mile away. Certainly having a paper = trace is impressive, but I would worry about maintaining it up all the = time.

Gary

 

From:= psn-l-request@.............. [mailto:psn-l-request@............... On = Behalf Of Edward Ianni
Sent: Saturday, October 31, 2009 10:29 AM
To: psn-l@..............
Subject: Re: HELICORDER value

 

This is an interesting point. It would be very nice to be = alerted audibly when an event is actually being received (occurring) in one of our data logging/analysis programs. I assume it's not that easy to do because of = the varying noise and event levels.   = Ed. 


With the drum recorder I am preserving a bit of history and the drum is = what impresses visitors. It is also my warning signal as it sits in our = living room and you can hear the pen skritching on the paper when the quake comes = in. To me, nothing beats the WOW-factor of watching a world-class quake come in = on a drum recorder.

George


At 07:36 AM 10/28/2009, you wrote:

For a lot less trouble why not simply get
A wide screen LED TV and a LAPTOP ?

I bet they may even be less expensive
than those drum recorders ?

Capillary action sounds like the
trees use to pick up water from their roots
???
I think the pumping is really caused by
the outflow (EVAPORATION OR ? MOVING PAPER)
pulling up on the reservoir
as the ink goes to the paper.
The capillary action only keeps
the ink in the tube and little more.

INTERESTING, never thought of this before.


You guys need to study plant roots & Leaves
to understand your own equipment.


----- Original Message ----- From: "Jan Froom" <JDarwin@.............>
To: <psn-l@..............>
Sent: Tuesday, October 27, 2009 1:52 PM
Subject: Re: TELEDYNE-GEOTECH HELICORDER Ink Pen



You want capillary attraction to pull the ink out = of the ink reservoir, so you have to have the top of the ink in the reservoir below = the pen level, otherwise the ink will siphon causing a very wide inky = trace. 
I use a simple plastic one oz bottle which I've placed two brass tubes = in the lid, one going to the bottom of the
bottle and one just though the top for a air vent. The one going to the = bottom of the bottle is then connected to the pen using
neoprene tubing. To get the whole thing going... I put my finger over = the air vent tube, squeeze the bottle until ink comes out
the pen, then remove my finger from the air vent, and release the = squeeze on the bottle.
The pen opening must be _*EXACTLY*_ tangent to the face of the drum... I installed the pen... and then put a very fine sand
paper on the drum surface and sanded the pen to get that tangent = fit.
Getting the pen to pull ink was the hardest part of my installation = and
I probably spent more time getting the pen to work... than anything = else. Having George Bush & Steve Hammond available for suggestions and = support was the only way I got mine going.
Another interesting point is the force at which the pen makes contact = with the paper...
our pens have a counter weight on a screw at the back end of the pen = which can be adjusted to adjust the contact force.
Too light and pen will skip on a large rapid swings... too heavy and = you've decreased your sensitivity.
I'm curious as to how many other "drummers" are out there?
Jan in Gilroy
Stephen Hammond wrote:


Hi, the ink will flow if the reservoir fluid level is above the pen. The = trick is to keep it from flowing too much. I used a wire clamp on the tubing = to cut the flow down. Professional models used low pressure pumps and an fin = valve. If I can suggest, search online for "chart pen ink" and you will = find the Recorder Charts Pens Company in Newhall CA. 800-758-0740. While they = do not list your unit they have a large selection of professional pens, ink and = paper. It might be worth a trip to the website or even a call to see what they = can offer in the way of a solution.

Steve

 

*From:* psn-l-request@.............. [ = mailto:psn-l-request@..............] *On Behalf Of *James Allen
*Sent:* Saturday, October 24, 2009 9:46 PM
*To:* psn-l@..............
*Subject:* Re: TELEDYNE-GEOTECH HELICORDER

 

Steve Hammond

Is there need for a special reservoir to insert the capillary tubing = into or will the ink start flowing by the action of the pen on the chart = paper?

Thanks

James Allen

    ----- Original Message -----

    *From:* Stephen Hammond < = mailto:shammon1@.............>

    *To:* psn-l@.............. < = mailto:psn-l@..............>

    *Sent:* Saturday, October 24, 2009 8:41 PM

    *Subject:* RE: TELEDYNE-GEOTECH HELICORDER

    

    There is a typo. Not needs try needle... Steve

    

    *From:* psn-l-request@..............
    < mailto:psn-l-request@..............>
    [ mailto:psn-l-request@..............] *On Behalf Of *Stephen = Hammond
    *Sent:* Saturday, October 24, 2009 8:38 PM
    *To:* psn-l@.............. < = mailto:psn-l@..............>
    *Subject:* RE: TELEDYNE-GEOTECH HELICORDER

    

    For some time some PSN members were using hypodermic = needs to
    build ink pens. You simply grind the point off and = have a
    precession tip that  can then be connected to = the reservoir using
    a capillary feed tube. We learned the process from = Howard who used
    this design back in the first Bay area seismic = station way before
    our time in the 40's. I ran two drum recorders back = around 1990
    and Jan Froom currently has a display station at = Bonfante Gardens
     in Gilroy CA that has a permanent display he = put together for
    them also using this design.

    Regards, Steve Hammond PSN Aptos, CA

    

    

_______________________________________________________= ___

Public Seismic Network Mailing List (PSN-L)

See http://www.seismicnet.co= m/maillist.html for more information.


George Bush
Sea Ranch, CA, USA
38.73775N, 123.48882W


No virus found in this incoming message.
Checked by AVG - www.avg.com
Version: 8.5.423 / Virus Database: 270.14.40/2471 - Release Date: = 10/31/09 07:53:00

Subject: Re: HELICORDER value From: "Edward Ianni" edwianni1@........... Date: Sat, 31 Oct 2009 17:17:01 -0100 Thanks Gary, I wasn't that familiar with WinSDR. Ed. ----- Original Message -----=20 From: Gary Lindgren=20 To: psn-l@................. Sent: Saturday, October 31, 2009 4:59 PM Subject: RE: HELICORDER value Edward, WinSDR has audible alarms built in the application. Different sounds = whether close by or teleseismic events. You just have to make sure you = turn the speaker down at night unless you want to wake up because of a = heavy freight train going down the track a mile away. Certainly having a = paper trace is impressive, but I would worry about maintaining it up all = the time. Gary =20 From: psn-l-request@.............. = [mailto:psn-l-request@............... On Behalf Of Edward Ianni Sent: Saturday, October 31, 2009 10:29 AM To: psn-l@.............. Subject: Re: HELICORDER value =20 This is an interesting point. It would be very nice to be alerted = audibly when an event is actually being received (occurring) in one of = our data logging/analysis programs. I assume it's not that easy to do = because of the varying noise and event levels. Ed.=20 With the drum recorder I am preserving a bit of history and the drum = is what impresses visitors. It is also my warning signal as it sits in = our living room and you can hear the pen skritching on the paper when = the quake comes in. To me, nothing beats the WOW-factor of watching a = world-class quake come in on a drum recorder. George At 07:36 AM 10/28/2009, you wrote: For a lot less trouble why not simply get A wide screen LED TV and a LAPTOP ? I bet they may even be less expensive than those drum recorders ? Capillary action sounds like the trees use to pick up water from their roots ??? I think the pumping is really caused by the outflow (EVAPORATION OR ? MOVING PAPER) pulling up on the reservoir as the ink goes to the paper. The capillary action only keeps the ink in the tube and little more. INTERESTING, never thought of this before. You guys need to study plant roots & Leaves to understand your own equipment. ----- Original Message ----- From: "Jan Froom" = To: Sent: Tuesday, October 27, 2009 1:52 PM Subject: Re: TELEDYNE-GEOTECH HELICORDER Ink Pen You want capillary attraction to pull the ink out of the ink = reservoir, so you have to have the top of the ink in the reservoir below = the pen level, otherwise the ink will siphon causing a very wide inky = trace. =20 I use a simple plastic one oz bottle which I've placed two brass = tubes in the lid, one going to the bottom of the bottle and one just though the top for a air vent. The one going to = the bottom of the bottle is then connected to the pen using neoprene tubing. To get the whole thing going... I put my finger = over the air vent tube, squeeze the bottle until ink comes out the pen, then remove my finger from the air vent, and release the = squeeze on the bottle. The pen opening must be _*EXACTLY*_ tangent to the face of the = drum... I installed the pen... and then put a very fine sand paper on the drum surface and sanded the pen to get that tangent = fit. Getting the pen to pull ink was the hardest part of my installation = and I probably spent more time getting the pen to work... than anything = else. Having George Bush & Steve Hammond available for suggestions and = support was the only way I got mine going. Another interesting point is the force at which the pen makes = contact with the paper... our pens have a counter weight on a screw at the back end of the pen = which can be adjusted to adjust the contact force. Too light and pen will skip on a large rapid swings... too heavy and = you've decreased your sensitivity. I'm curious as to how many other "drummers" are out there? Jan in Gilroy Stephen Hammond wrote: Hi, the ink will flow if the reservoir fluid level is above the pen. = The trick is to keep it from flowing too much. I used a wire clamp on = the tubing to cut the flow down. Professional models used low pressure = pumps and an fin valve. If I can suggest, search online for "chart pen = ink" and you will find the Recorder Charts Pens Company in Newhall CA. = 800-758-0740. While they do not list your unit they have a large = selection of professional pens, ink and paper. It might be worth a trip = to the website or even a call to see what they can offer in the way of a = solution. Steve =20 *From:* psn-l-request@.............. [ = mailto:psn-l-request@............... *On Behalf Of *James Allen *Sent:* Saturday, October 24, 2009 9:46 PM *To:* psn-l@.............. *Subject:* Re: TELEDYNE-GEOTECH HELICORDER =20 Steve Hammond Is there need for a special reservoir to insert the capillary tubing = into or will the ink start flowing by the action of the pen on the chart = paper? Thanks James Allen ----- Original Message ----- *From:* Stephen Hammond < mailto:shammon1@.............> *To:* psn-l@.............. < mailto:psn-l@..............> *Sent:* Saturday, October 24, 2009 8:41 PM *Subject:* RE: TELEDYNE-GEOTECH HELICORDER =20 There is a typo. Not needs try needle... Steve =20 *From:* psn-l-request@.............. < mailto:psn-l-request@..............> [ mailto:psn-l-request@............... *On Behalf Of *Stephen = Hammond *Sent:* Saturday, October 24, 2009 8:38 PM *To:* psn-l@.............. < mailto:psn-l@..............> *Subject:* RE: TELEDYNE-GEOTECH HELICORDER =20 For some time some PSN members were using hypodermic needs to build ink pens. You simply grind the point off and have a precession tip that can then be connected to the reservoir = using a capillary feed tube. We learned the process from Howard who = used this design back in the first Bay area seismic station way = before our time in the 40's. I ran two drum recorders back around 1990 and Jan Froom currently has a display station at Bonfante = Gardens in Gilroy CA that has a permanent display he put together for them also using this design. Regards, Steve Hammond PSN Aptos, CA =20 =20 __________________________________________________________ Public Seismic Network Mailing List (PSN-L) To leave this list email PSN-L-REQUEST@.............. with the body = of the message (first line only): unsubscribe See http://www.seismicnet.com/maillist.html for more information. George Bush Sea Ranch, CA, USA 38.73775N, 123.48882W=20 -------------------------------------------------------------------------= --- No virus found in this incoming message. Checked by AVG - www.avg.com=20 Version: 8.5.423 / Virus Database: 270.14.40/2471 - Release Date: = 10/31/09 07:53:00 -------------------------------------------------------------------------= ----- No virus found in this incoming message. Checked by AVG - www.avg.com=20 Version: 8.5.423 / Virus Database: 270.14.40/2471 - Release Date: = 10/31/09 07:53:00
Thanks Gary, I wasn't = that familiar with=20 WinSDR.  Ed.
----- Original Message -----
From:=20 Gary=20 Lindgren
Sent: Saturday, October 31, = 2009 4:59=20 PM
Subject: RE: HELICORDER = value

Edward,

WinSDR=20 has audible alarms built in the application. Different sounds whether = close by=20 or teleseismic events. You just have to make sure you turn the speaker = down at=20 night unless you want to wake up because of a heavy freight train = going down=20 the track a mile away. Certainly having a paper trace is impressive, = but I=20 would worry about maintaining it up all the = time.

Gary

 

From:=20 psn-l-request@.............. [mailto:psn-l-request@............... = On=20 Behalf Of Edward Ianni
Sent: Saturday, October 31, 2009 = 10:29=20 AM
To: psn-l@..............
Subject: Re: = HELICORDER=20 value

 

This is = an=20 interesting point. It would be very nice to be alerted audibly = when an=20 event is actually being received (occurring) in one of our data=20 logging/analysis programs. I assume it's not that easy to do because = of the=20 varying noise and event levels.  =20 Ed. 


With the drum recorder I am preserving a = bit of=20 history and the drum is what impresses visitors. It is also my = warning=20 signal as it sits in our living room and you can hear the pen = skritching on=20 the paper when the quake comes in. To me, nothing beats the = WOW-factor of=20 watching a world-class quake come in on a drum=20 recorder.

George


At 07:36 AM 10/28/2009, you=20 wrote:

For a lot less trouble why not simply get
A = wide=20 screen LED TV and a LAPTOP ?

I bet they may even be less=20 expensive
than those drum recorders ?

Capillary action = sounds like=20 the
trees use to pick up water from their roots
???
I think = the=20 pumping is really caused by
the outflow (EVAPORATION OR ? MOVING=20 PAPER)
pulling up on the reservoir
as the ink goes to the=20 paper.
The capillary action only keeps
the ink in the tube and = little=20 more.

INTERESTING, never thought of this = before.


You guys=20 need to study plant roots & Leaves
to understand your own=20 equipment.


----- Original Message ----- From: "Jan Froom" = <JDarwin@.............>
To: = <psn-l@..............>
Sent:=20 Tuesday, October 27, 2009 1:52 PM
Subject: Re: TELEDYNE-GEOTECH=20 HELICORDER Ink Pen



You want capillary attraction to pull the ink = out of the=20 ink reservoir, so you have to have the top of the ink in the = reservoir below=20 the pen level, otherwise the ink will siphon causing a very wide = inky=20 trace. 
I use a simple plastic one oz bottle which I've = placed two=20 brass tubes in the lid, one going to the bottom of the
bottle and = one=20 just though the top for a air vent. The one going to the bottom of = the=20 bottle is then connected to the pen using
neoprene tubing. To get = the=20 whole thing going... I put my finger over the air vent tube, squeeze = the=20 bottle until ink comes out
the pen, then remove my finger from = the air=20 vent, and release the squeeze on the bottle.
The pen opening must = be=20 _*EXACTLY*_ tangent to the face of the drum... I installed the = pen... and=20 then put a very fine sand
paper on the drum surface and sanded = the pen to=20 get that tangent fit.
Getting the pen to pull ink was the hardest = part of=20 my installation and
I probably spent more time getting the pen to = work...=20 than anything else. Having George Bush & Steve Hammond available = for=20 suggestions and support was the only way I got mine = going.
Another=20 interesting point is the force at which the pen makes contact with = the=20 paper...
our pens have a counter weight on a screw at the back = end of the=20 pen which can be adjusted to adjust the contact force.
Too light = and pen=20 will skip on a large rapid swings... too heavy and you've decreased = your=20 sensitivity.
I'm curious as to how many other "drummers" are out=20 there?
Jan in Gilroy
Stephen Hammond = wrote:


Hi, the ink will flow if the reservoir = fluid level is=20 above the pen. The trick is to keep it from flowing too much. I used = a wire=20 clamp on the tubing to cut the flow down. Professional models used = low=20 pressure pumps and an fin valve. If I can suggest, search online for = "chart=20 pen ink" and you will find the Recorder Charts Pens Company in = Newhall CA.=20 800-758-0740. While they do not list your unit they have a large = selection=20 of professional pens, ink and paper. It might be worth a trip to the = website=20 or even a call to see what they can offer in the way of a=20 solution.

Steve

 

*From:*=20 psn-l-request@.............. [=20 mailto:psn-l-request@..............] *On Behalf Of *James=20 Allen
*Sent:* Saturday, October 24, 2009 9:46 PM
*To:*=20 psn-l@..............
*Subject:* Re: TELEDYNE-GEOTECH=20 HELICORDER

 

Steve Hammond

Is there need = for a=20 special reservoir to insert the capillary tubing into or will the = ink start=20 flowing by the action of the pen on the chart=20 paper?

Thanks

James Allen

    = -----=20 Original Message -----

    *From:* Stephen = Hammond=20 <=20 mailto:shammon1@.............>

    = *To:*=20 psn-l@.............. <=20 mailto:psn-l@..............>

    = *Sent:*=20 Saturday, October 24, 2009 8:41 PM

    = *Subject:* RE:=20 TELEDYNE-GEOTECH HELICORDER

    =20

    There is a typo. Not needs try needle...=20 Steve

    

    = *From:*=20 psn-l-request@..............
    <=20 mailto:psn-l-request@..............>
    = [=20 mailto:psn-l-request@..............] *On Behalf Of *Stephen=20 Hammond
    *Sent:* Saturday, October 24, 2009 = 8:38=20 PM
    *To:* psn-l@.............. <=20 mailto:psn-l@..............>
    *Subject:* = RE:=20 TELEDYNE-GEOTECH HELICORDER

    =20

    For some time some PSN members were using = hypodermic needs to
    build ink pens. You simply = grind=20 the point off and have a
    precession tip = that  can=20 then be connected to the reservoir using
    a = capillary=20 feed tube. We learned the process from Howard who = used
   =20 this design back in the first Bay area seismic station way=20 before
    our time in the 40's. I ran two drum = recorders=20 back around 1990
    and Jan Froom currently has a = display=20 station at Bonfante Gardens
     in Gilroy CA = that=20 has a permanent display he put together for
    = them also=20 using this design.

    Regards, Steve Hammond = PSN=20 Aptos, CA

     =

    =20

_______________________________________________________= ___

Public=20 Seismic Network Mailing List (PSN-L)

To leave this list email = PSN-L-REQUEST@.............. with the body of the message (first = line only):=20 unsubscribe
See http://www.seismicnet.co= m/maillist.html=20 for more information.


George Bush
Sea Ranch, CA, USA
38.73775N, 123.48882W=20


No virus found in this incoming = message.
Checked=20 by AVG - www.avg.com
Version: 8.5.423 / Virus Database: = 270.14.40/2471 -=20 Release Date: 10/31/09 07:53:00


No virus found in this incoming message.
Checked by AVG = -=20 www.avg.com
Version: 8.5.423 / Virus Database: 270.14.40/2471 - = Release=20 Date: 10/31/09 07:53:00
Subject: Re: WINQUAKE QUESTION ABOUT HEADER INFO From: Larry Cochrane lcochrane@.............. Date: Mon, 02 Nov 2009 19:52:52 -0800 Geoff, This has been discussed before. WinQuake skips the first few samples in the event file so that the display starts at the top of the first second. This is only done if there is a fraction of a second in the nanosecond start time field. > A. Put the fraction 0.151 into the nanoseconds variable times one billion This is the correct way of doing this. Since the nanosecond field is a 32 bit long you will need to multiply .151 times one billion and place the integer result into the nanosecond field. Regards, Larry Cochrane Redwood City, PSN Geoffrey wrote: > Hello Folks; > > Please bear with me here I know you do not like to hear this > but it will help me decide how to finish my program. > > I am rewriting my recording and display programs > to use 12 bits instead of 8 to avoid saturation problems. > In my display program I create a PSN4 file to be able to > read times in winquake and share with the rest of you. > I am having problems getting WINQUAKE to properly > show the time of the very first sample since > MY first sample can be something OTHER than > an exact second and usually has a fraction. > > There are two Items in the header that affect time readings > And I'm wondering how to properly use them. > > WINQUAKE TYPE4 HEADER DATA > GIVEN: FIRST SAMPLE TIME 00:00:35.151 > Hour? == 00 byte value 0 to 23 > Minute? == 00 byte value 0 to 59 > Seconds? == 35 byte value 0 to 59 > SPACE HOLDER? byte value 0 > NANOseconds& LONG signed integer value 4 bytes low endean > 0 to 999,999,999 > OFFSETseconds# DOUBLE floating point value 8 bytes IEEE > > > Find: What is the proper way to indicate > the fractional value which remains ? > > A. Put the fraction 0.151 into the nanoseconds variable times one billion > B. Put the fraction 0.151 into the offset area following the nanoseconds area > C. CROP the recorded DATA to start at an exact second > D. THERE IS NO WAY TO GET THE FIRST SAMPLE TO SHOW THE PROPER FRACTIONAL VALUE > > What's the best answer here ? > > I know if I crop the file to an exact cal mark second > I get pretty good fractional times. I am guessing > this may be the best way to go since I may be using > WQ in ways it was not designed to be used. > This will mean saving 4 minutes of modulo history > instead of three. I do not want to do this > unless absolutely necessary. > > When I look at my own data I will assign > discreet date-times UTC to each sample > relative to a given calibration mark > and not guess between samples. > The cal sample happens at the transition > between second 59 and second zero the first > sample after this event and I call that the > exact second and calculate all other sample times > from that one reference point. > WINQUAKE works different, possibly better, > I just need to understand it better. > The times I use are in the WINQUAKE "?" > type relating to synchronization with WWV > radio broadcast. > > Thanks for answers, > geoff > > ps, I have found lots of errors in my older program > leading to not so good time readings in the past. > Every time I do this, the results seem better > than before. > But now I'm reaching the point of diminishing returns. > > > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: WINQUAKE QUESTION ABOUT HEADER INFO From: "Geoffrey" gmvoeth@........... Date: Tue, 3 Nov 2009 08:43:35 -0700 Hello Larry and Thanks for your answers; One other complex question which also may seem silly to you. Does your program invent a new time for imaginary (thoughts of the mind and not a math number) samples that would through the human imagination be a START AT an exact second then the program create its own samples by the numbers from start to end ? This means to me the samples magnitudes being displayed are not the same as the samples magnitudes which were taken. Your program would then be creating a new set of imaginary samples and not using the originals. This means an adjustment to the overall picture in time. (shifting the entire picture ever so slightly) Otherwise the very first sample time instant (sample zero) would have to be identicle to the one given by the supplier of the data. Im not sure exactly how to test this but i may pursue it simply to satisfy my own curiosity by inventing artificial data sets. To me it appears you are NOT adjusting the picture because your samples seem to possess the very same magnitudes of the original samples provided to the program? If you were adjusting the overall picture the magnitudes would be a count or two in difference from the originals ? Comment please, Im not trying to cause you troubles just to understand without knowing your source code. Suggestion for winquake program: I have an FFT like waterfall display Id like to let you see and comment on for the latest california quake just received. Time is thirty minutes and freq is like 4.5 Hz. http://gmvoeth.home.mchsi.com/091103_105436_FFT.BMP time left to right, past to present 30 minutes freq bottom to top, low to high 4.5 Hz It would be nice if your program could display data in this way. Regards; geoff ----- Original Message ----- From: "Larry Cochrane" To: Sent: Monday, November 02, 2009 8:52 PM Subject: Re: WINQUAKE QUESTION ABOUT HEADER INFO > Geoff, > > This has been discussed before. WinQuake skips the first few samples in the event > file so that the display starts at the top of the first second. This is only done if > there is a fraction of a second in the nanosecond start time field. > > > A. Put the fraction 0.151 into the nanoseconds variable times one billion > > This is the correct way of doing this. Since the nanosecond field is a 32 bit long > you will need to multiply .151 times one billion and place the integer result into > the nanosecond field. > > Regards, > Larry Cochrane > Redwood City, PSN > > Geoffrey wrote: >> Hello Folks; >> >> Please bear with me here I know you do not like to hear this >> but it will help me decide how to finish my program. >> >> I am rewriting my recording and display programs >> to use 12 bits instead of 8 to avoid saturation problems. >> In my display program I create a PSN4 file to be able to >> read times in winquake and share with the rest of you. >> I am having problems getting WINQUAKE to properly >> show the time of the very first sample since >> MY first sample can be something OTHER than >> an exact second and usually has a fraction. >> >> There are two Items in the header that affect time readings >> And I'm wondering how to properly use them. >> >> WINQUAKE TYPE4 HEADER DATA >> GIVEN: FIRST SAMPLE TIME 00:00:35.151 >> Hour? == 00 byte value 0 to 23 >> Minute? == 00 byte value 0 to 59 >> Seconds? == 35 byte value 0 to 59 >> SPACE HOLDER? byte value 0 >> NANOseconds& LONG signed integer value 4 bytes low endean >> 0 to 999,999,999 >> OFFSETseconds# DOUBLE floating point value 8 bytes IEEE >> >> >> Find: What is the proper way to indicate >> the fractional value which remains ? >> >> A. Put the fraction 0.151 into the nanoseconds variable times one billion >> B. Put the fraction 0.151 into the offset area following the nanoseconds area >> C. CROP the recorded DATA to start at an exact second >> D. THERE IS NO WAY TO GET THE FIRST SAMPLE TO SHOW THE PROPER FRACTIONAL VALUE >> >> What's the best answer here ? >> >> I know if I crop the file to an exact cal mark second >> I get pretty good fractional times. I am guessing >> this may be the best way to go since I may be using >> WQ in ways it was not designed to be used. >> This will mean saving 4 minutes of modulo history >> instead of three. I do not want to do this >> unless absolutely necessary. >> >> When I look at my own data I will assign >> discreet date-times UTC to each sample >> relative to a given calibration mark >> and not guess between samples. >> The cal sample happens at the transition >> between second 59 and second zero the first >> sample after this event and I call that the >> exact second and calculate all other sample times >> from that one reference point. >> WINQUAKE works different, possibly better, >> I just need to understand it better. >> The times I use are in the WINQUAKE "?" >> type relating to synchronization with WWV >> radio broadcast. >> >> Thanks for answers, >> geoff >> >> ps, I have found lots of errors in my older program >> leading to not so good time readings in the past. >> Every time I do this, the results seem better >> than before. >> But now I'm reaching the point of diminishing returns. >> >> >> __________________________________________________________ >> >> Public Seismic Network Mailing List (PSN-L) >> >> To leave this list email PSN-L-REQUEST@.............. with >> the body of the message (first line only): unsubscribe >> See http://www.seismicnet.com/maillist.html for more information. >> > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: QUAKE CATCHER BOINC (FIRST COME FIRST SERVED) From: "Geoffrey" gmvoeth@........... Date: Fri, 6 Nov 2009 09:47:08 -0700 "First Come First serve" "AS IS" "No GUARANTEES" "FREE" "UNCONDITIONAL" "ONLY ONE AVAILABLE" Hello to anyone with PSN who is really within Earthquake territory. I have a STANFORD UNIVERSITY three element USB sensor free to anyone Within the USA who is interested. Just send me your mail address and I will send it first class USPS uninsured. It is the WHITE model which is MEMS accelerometer I believe. THIS device is quite insensitive and really only good for someone within a quake area. You can learn more online as the QuakeCatcher program. gmvoeth@......... Being where i live it was a mistake for me to obtain this item. But may be right for you if you are living on top a quake area like Altadena/Pasadena or ?? . Regards; geoff __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: QUAKE CATCHER BOINC (FIRST COME FIRST SERVED) From: Canie canie@........... Date: Fri, 06 Nov 2009 09:00:48 -0800 Hey Geoff - I'd be happy to take a gander with it! I'm in Long Beach CA - lots of quakes down here! Canie At 08:47 AM 11/6/2009, you wrote: >"First Come First serve" "AS IS" "No GUARANTEES" "FREE" "UNCONDITIONAL" >"ONLY ONE AVAILABLE" > >Hello to anyone with PSN who is really within >Earthquake territory. > >I have a STANFORD UNIVERSITY three element USB sensor free to anyone >Within the USA who is interested. Just send me your mail address >and I will send it first class USPS uninsured. > >It is the WHITE model which is MEMS accelerometer I believe. > >THIS device is quite insensitive and really only good >for someone within a quake area. You can learn more online >as the QuakeCatcher program. > >gmvoeth@......... > >Being where i live it was a mistake for me to obtain this item. >But may be right for you if you are living on top a quake area >like Altadena/Pasadena or ?? . > >Regards; >geoff > >__________________________________________________________ > >Public Seismic Network Mailing List (PSN-L) > >To leave this list email PSN-L-REQUEST@.............. with the body >of the message (first line only): unsubscribe >See http://www.seismicnet.com/maillist.html for more information. __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Sprengnether From: "Edward Ianni" edwianni1@........... Date: Fri, 06 Nov 2009 23:10:24 -0100 I have a question about an old instrument that I picked up years ago. = The markings are Sprengnehter Instrument Co, St Louis, Mo and an = engraved number 4218. It is in a square metal box (about 4"x 8"x 6" and = weights about 6/7 lbs). It seems to have a liquid in it and it does have = a bubble level on top of it. It has 4 wires coming out of an old = shielded/sheathed cable. Two of them, when the box is tilted, put out a = spike voltage (they are red/black and measure 11k ohms) The other two = wires (green/white don't put out a voltage and measure about 6 ohms and = neither set of wires have a resistance relationship to the other two).I = assumed it was a strong motion indicator. Playing around with it, = yesterday, I hooked it up in place of my lehman horizontal sensor and it = does pass the "walkup test" generally producing one or two sine wave = signals from the red/black wires being fed into the existing setup. Now, = a few questions. Does anyone know anything about this instrument, and = what are the green/white wires for (an input voltage)? Thank you in = advance. Ed.=20

I have a question about an old instrument that I picked up years ago. = The=20 markings are Sprengnehter Instrument Co, St Louis, Mo and an engraved = number=20 4218. It is in a square metal box (about 4"x 8"x 6" and weights about = 6/7 lbs).=20 It seems to have a liquid in it and it does have a bubble level on top = of it. It=20 has 4 wires coming out of an old shielded/sheathed cable. Two of them, = when the=20 box is tilted, put out a spike voltage (they are red/black and measure = 11k ohms)=20 The other two wires (green/white don't put out a voltage and measure = about 6=20 ohms and neither set of wires have a resistance relationship to the = other two).I=20 assumed it was a strong motion indicator. Playing around with it, = yesterday, I=20 hooked it up in place of my lehman horizontal sensor and it does pass = the=20 "walkup test" generally producing one or two sine wave signals from the=20 red/black wires being fed into the existing setup. Now, a few questions. = Does=20 anyone know anything about this instrument, and what are the green/white = wires=20 for (an input voltage)? Thank you in advance. Ed.=20

Subject: Re: QUAKE CATCHER BOINC (FIRST COME FIRST SERVED) From: Brad Douglas rez@.................. Date: Fri, 06 Nov 2009 20:10:19 -0800 On 11/06/2009 08:47 AM, Geoffrey wrote: > "First Come First serve" "AS IS" "No GUARANTEES" "FREE" "UNCONDITIONAL" > "ONLY ONE AVAILABLE" > > Hello to anyone with PSN who is really within > Earthquake territory. > > I have a STANFORD UNIVERSITY three element USB sensor free to anyone > Within the USA who is interested. Just send me your mail address > and I will send it first class USPS uninsured. > > It is the WHITE model which is MEMS accelerometer I believe. I also picked up one of these a few months ago. I'm actually using it for a different purpose at the moment. FWIW, this is the company who made the device (JoyWarrior24F8): http://www.codemercs.com/index.php?id=80&L=1 ....and here's a link to the sensor documentation: http://www.codemercs.com/uploads/media/JW24F8_Datasheet_01.pdf It has a EPROM selectable range setting from: +/-2g, +/-4g, +/-8g. It has 10-bit resolution/axis with a max sampling rate of 125 samples/s. -- 73, de KB8UYR/6 Brad Douglas __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: QUAKE CATCHER BOINC (FIRST COME FIRST SERVED) From: "Geoffrey" gmvoeth@........... Date: Fri, 6 Nov 2009 21:46:35 -0700 This device has been sent out today. It is no longer available from myself. The cable was too short for me to use I need about 40 feet of usb cable. I was not aware that usb was only like 16 feet without special additional equipment. There is no place within 16 feet I can place such a thing. I have tested this idea by using a jump drive and it would not work over about 16 feet of cable length. I wanted to place the sensor on the very same pad the current geophone is located. Hopefully the person I sent it to will make better use of it. Thanks, I send to those who responded. Regards geoff ----- Original Message ----- From: "Brad Douglas" To: Sent: Friday, November 06, 2009 9:10 PM Subject: Re: QUAKE CATCHER BOINC (FIRST COME FIRST SERVED) > On 11/06/2009 08:47 AM, Geoffrey wrote: >> "First Come First serve" "AS IS" "No GUARANTEES" "FREE" "UNCONDITIONAL" >> "ONLY ONE AVAILABLE" >> >> Hello to anyone with PSN who is really within >> Earthquake territory. >> >> I have a STANFORD UNIVERSITY three element USB sensor free to anyone >> Within the USA who is interested. Just send me your mail address >> and I will send it first class USPS uninsured. >> >> It is the WHITE model which is MEMS accelerometer I believe. > > I also picked up one of these a few months ago. I'm actually using it > for a different purpose at the moment. > > FWIW, this is the company who made the device (JoyWarrior24F8): > http://www.codemercs.com/index.php?id=80&L=1 > > ...and here's a link to the sensor documentation: > http://www.codemercs.com/uploads/media/JW24F8_Datasheet_01.pdf > > It has a EPROM selectable range setting from: +/-2g, +/-4g, +/-8g. It > has 10-bit resolution/axis with a max sampling rate of 125 samples/s. > > > -- > 73, de KB8UYR/6 Brad Douglas > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Stormy Seas From: ian ian@........... Date: Sat, 07 Nov 2009 10:19:50 +0000 it seems to be getting stormy in the seas around the UK. In the last few hours my seismometer has started jumping up and down, as it were. Looking at the BGS graph, http://www.earthquakes.bgs.ac.uk/helicorder/heli_dir_vhz/LRW_VHZ_GB_00.2009110700.gif , it's around a 12 second period and a longer period of around 10 minutes. Mine shows both of these components too. Ian __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Stormy Seas From: Dave Nelson dave.nelson@............... Date: Sat, 07 Nov 2009 22:18:47 +1100 wow niceview on the seismo, Ian Takes me back to when I had a recorder going in New Zealand and watching the same thing as a cold front moved in from the south... those same style bursts of wiggles :) take care Dave N Sydney Oz __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Stormy Seas From: ian ian@........... Date: Sat, 07 Nov 2009 11:54:07 +0000 Hi, thanks but I should confess that the trace is from the BGS. Here's a snapshot of mine: http://www.festivalpreviews.com/mte09/rtLatestQ.jpg Cheers Ian Dave Nelson wrote: > wow niceview on the seismo, Ian > > Takes me back to when I had a recorder going in New Zealand and > watching the same thing as a cold front moved in from the south... > those same style bursts > of wiggles :) > > take care > Dave N > Sydney > Oz > > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with the body of > the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Stormy Seas From: Stephen & Kathy skmort@............ Date: Sat, 07 Nov 2009 11:18:02 -0800 Check out the wave action around the UK...=A0 = Watch for wrap around problems:
https://www.fnmoc.navy.mil/wxmap_cgi/= cgi-bin/wxmap_single.cgi?area=3Dww3_atlantic&dtg=3D2009110712&pro= d=3Dsgwvht&tau=3D000&set=3DSeaState
Source link in case you have problems:
https://www.fnmoc.navy.mil/ww3_cgi/index.html

Here in N Calif we're also getting storm related seismic activity from along the US northwest coast.

=A0 Stephen
=A0 PSN Station #55
=A0 38.828N=A0 120.979W
=A0 near Pilot Hill Ca USA

ian wrote:
it seems to be getting stormy in the seas around the UK.=A0 In the last few hours my seismometer has started jumping up and down, as it were.=A0 Looking at the BGS graph, http://www.earth= quakes.bgs.ac.uk/helicorder/heli_dir_vhz/LRW_VHZ_GB_00.2009110700.gif= ,=A0 it's around a 12 second period and a longer period of around 10 minutes.=A0 Mine shows both of these components too.

Ian

Subject: Re: Stormy Seas From: "Geoffrey" gmvoeth@........... Date: Sat, 7 Nov 2009 12:27:40 -0700 Neato, In the 1970s I was once in 40 ft seas off Taiwan and they looked like mountains one right after the other. ----- Original Message ----- From: "ian" To: Sent: Saturday, November 07, 2009 3:19 AM Subject: Stormy Seas > it seems to be getting stormy in the seas around the UK. In the last > few hours my seismometer has started jumping up and down, as it were. > Looking at the BGS graph, > http://www.earthquakes.bgs.ac.uk/helicorder/heli_dir_vhz/LRW_VHZ_GB_00.2009110700.gif > , it's around a 12 second period and a longer period of around 10 > minutes. Mine shows both of these components too. > > Ian > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Stormy Seas From: ian ian@........... Date: Sun, 08 Nov 2009 13:51:49 +0000 Hi, great link and wave height graph. Looks like the waves approaching Ireland were almost off the scale at around 50 Ft. Things are calming down a bit now. Ian Stephen & Kathy wrote: > Check out the wave action around the UK... Watch for wrap around > problems: > https://www.fnmoc.navy.mil/wxmap_cgi/cgi-bin/wxmap_single.cgi?area=ww3_atlantic&dtg=2009110712&prod=sgwvht&tau=000&set=SeaState > Source link in case you have problems: > https://www.fnmoc.navy.mil/ww3_cgi/index.html > > Here in N Calif we're also getting storm related seismic activity from > along the US northwest coast. > > Stephen > PSN Station #55 > 38.828N 120.979W > near Pilot Hill Ca USA > > ian wrote: >> it seems to be getting stormy in the seas around the UK. In the last >> few hours my seismometer has started jumping up and down, as it >> were. Looking at the BGS graph, >> http://www.earthquakes.bgs.ac.uk/helicorder/heli_dir_vhz/LRW_VHZ_GB_00.2009110700.gif >> , it's around a 12 second period and a longer period of around 10 >> minutes. Mine shows both of these components too. >> >> Ian >> Hi,

great link and wave height graph.  Looks like the waves approaching Ireland were almost off the scale at around 50 Ft.  Things are calming down a bit now.

Ian

Stephen & Kathy wrote:
Check out the wave action around the UK...  Watch for wrap around problems:
https://www.fnmoc.navy.mil/wxmap_cgi/cgi-bin/wxmap_single.cgi?area=ww3_atlantic&dtg=2009110712&prod=sgwvht&tau=000&set=SeaState
Source link in case you have problems:
https://www.fnmoc.navy.mil/ww3_cgi/index.html

Here in N Calif we're also getting storm related seismic activity from along the US northwest coast.

  Stephen
  PSN Station #55
  38.828N  120.979W
  near Pilot Hill Ca USA

ian wrote:
it seems to be getting stormy in the seas around the UK.  In the last few hours my seismometer has started jumping up and down, as it were.  Looking at the BGS graph, http://www.earthquakes.bgs.ac.uk/helicorder/heli_dir_vhz/LRW_VHZ_GB_00.2009110700.gif ,  it's around a 12 second period and a longer period of around 10 minutes.  Mine shows both of these components too.

Ian

Subject: WinQuake Times From: "Geoffrey" gmvoeth@........... Date: Mon, 9 Nov 2009 13:37:09 -0700 Hello PSN; FYI I made the changes to a conversion program of my own to invent a PSN4 file for my data and wish to announce that since I have placed the fractional value of the start time times a billion into the NANO SECOND area the times I now get from winquake appear to be proper. I have tested this using pulse marks made by myself then gone back into the program and checked the times. The proper way would be to use WWV minute marks I have not yet done this however I expect for amateur purposes that would be correct also. I now feel I can resume sending reports to whoever and expect the times to be correct or as correct as can be for my station. GVA teleseismic events appear very close agreement in form to the fellow in Washington State so I am guessing that phase (up is up) is proper also. I only do an SPZ channel so can not compare with those using N or E sensors. Roger Sparks Device seems to have a lower freq response so our comparisons will rarely be exact yet they seem very close in appearance. geoff __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: WinQuake Times From: RSparks rsparks@.......... Date: Tue, 10 Nov 2009 06:56:51 -0800 Good Morning Geoff, I don't quite know how to react to your posting because I am not working much in the area of quake timing. However, from the posting, I can see that you are watching my PSN quake reports so I need to tell you more about my equipment. First, my timing is not very exact. I installed a ClockCard into my computer, which is controlled by the software ClockWatch. I think I am accurate to within one second but I recognize that is very poor accuracy for seismic work. I am using a tweaked copy of Amaseis to record the events. Amaseis uses the PC time to change hours and each event is expected to be regularly spaced after that. Since my sample rate is about 10.3 samples per second, the chance of which hour the last/first sample fell into becomes a probability exercise. I have never investigated the accuracy of the clock in the A/D device but it is pretty good so the samples should be well spaced. I am using an earlier Saum A/D device that I modified slightly to have a wider frequency response, with the modifications hopefully increasing the high pass characteristics. I was satisfied when I could see our local Washington quakes which have a higher frequency than the teleseismic events. The sensor is the next step from the device I posted some time ago at http://www.fairpoint.net/~sparksite/CSpring%20Seismometer.html . Damping is with magnetic braking. The device does not record a strictly vertical motion because the mass axis is tilted (to improve the low frequency response) giving a response similar to the response from the CSpring Seismometer (which is incorrectly claimed to be a (only) vertical sensing device). Both the CSpring device and my present device respond to horizontal motion to the extent dictated by the vector angle from the pivot point to the center of mass. Your comment about wave form seems to say that the wave forms between your recordings and mine seem to be similar. If that is what you intend to say, I am somewhat surprised because this station is located between some mountains which I would (I think) cause reflections that would change the wave form. I have wondered if amateur seismic stations could utilize the interference rendering technique to actually map the surface and subsurface features of the earth somewhat akin to what is done with medical imaging? My own knowledge of imaging is too weak to venture an opinion. Thanks for sharing your results. Roger psn-l-digest-request@.............. wrote: > .------ ------ ------ ------ ------ ------ ------ ------ ------ ------. > | Message 1 | > '------ ------ ------ ------ ------ ------ ------ ------ ------ ------' > Subject: WinQuake Times > From: "Geoffrey" > Date: Mon, 9 Nov 2009 13:37:09 -0700 > > Hello PSN; > > FYI > I made the changes to a conversion program > of my own to invent a PSN4 file for my data > and wish to announce that since I have > placed the fractional value of the start time > times a billion into the NANO SECOND > area the times I now get from winquake appear > to be proper. I have tested this using > pulse marks made by myself then gone back > into the program and checked the times. > The proper way would be to use WWV minute marks > I have not yet done this however I expect for > amateur purposes that would be correct also. > > I now feel I can resume sending reports > to whoever and expect the times to be correct > or as correct as can be for my station. > > GVA teleseismic events appear very close agreement > in form to the fellow in Washington State so I am > guessing that phase (up is up) is proper also. > I only do an SPZ channel so can not compare > with those using N or E sensors. > Roger Sparks Device seems to have a lower freq > response so our comparisons will rarely > be exact yet they seem very close in appearance. > > geoff > > > > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-DIGEST-REQUEST@.............. with > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. > > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: WinQuake Times From: "Geoffrey" gmvoeth@........... Date: Tue, 10 Nov 2009 09:22:44 -0700 Your Setup is the very kind I like to see. I once made a torsion seismometer using a spring made out of an aluminum antenna rod split down the middle and fastened at both ends in clamps like the scientists use. Then it had a long lever arm of wood with a magnet on the end. It was a hopeful dream that never realized itself due to annoying torments in my life. The period must have been longer than a second. I have faith (chuckle) in torsional kind of seismic devices. If you made two and put them back to back you may possibly cancel out tilt and only look at vertical motions. But not exactly sure. Thanks for the input Mr. Sparks, When I say a science clamp what you do is drill a hole in a piece of wood then cut the hole in half or only one side then you use a screw to clamp whatever in the hole. The cut area will take away just enough material to make a proper kind of clamp. I see these kind of clamps almost everywhere the engineers are building various things. You may see a similar thing in an automobile engine holding down the camshaft. I very much like your design and would like to know what you are using for the folded leaf springs. Your design requires no frictional boundaries. Like rolling or pivoting. Also, are you located on or close to bedrock. Is your device located outside some distance from human activity ? Have you ever considered using two identical sensors placed pointing in opposite directions to cancel out tilt ? Does your device require periodic adjustments ? What electronics are you using ? What program to take your data ? Thanks ahead of time for any responses. I make no apologies for my stupid questions, its the only way to learn in the absence of expensive books. I was a resident of Washington state while attached to the uss Bainbridge cgn25 stationed in Bremerton Washington. I will not pay taxes to any state I do not work in so I become a resident of any state I happen to work in. I guess Washington can have some of the biggest earthquakes in the world because it is close to a subduction boundary near the straights of Juan De Fuca. As an adult, I have been a resident of every state in which I ever worked. Maybe 5. I got stuck in Arizona or otherwise id be closer to high tech civilization, and not this electro-mechanical farmer, cowboy world of Arizona. Apache junction is the elephant graveyard of the white man. Like in those old Tarzan movies where all the elephants go to die. Except instead of elephants it is basically all white human kind of elephants. I cant say much nice about this place since it represents to me little more than a low security prison in which I happen to be an inmate. Seismic watching is a proper sport to escape the irritations of this dying elephant social world. Best Regards, geoff ----- Original Message ----- From: "RSparks" To: Sent: Tuesday, November 10, 2009 7:56 AM Subject: WinQuake Times > Good Morning Geoff, > > I don't quite know how to react to your posting because I am not working > much in the area of quake timing. However, from the posting, I can see > that you are watching my PSN quake reports so I need to tell you more > about my equipment. > > First, my timing is not very exact. I installed a ClockCard into my > computer, which is controlled by the software ClockWatch. I think I am > accurate to within one second but I recognize that is very poor accuracy > for seismic work. > > I am using a tweaked copy of Amaseis to record the events. Amaseis uses > the PC time to change hours and each event is expected to be regularly > spaced after that. Since my sample rate is about 10.3 samples per > second, the chance of which hour the last/first sample fell into becomes > a probability exercise. I have never investigated the accuracy of the > clock in the A/D device but it is pretty good so the samples should be > well spaced. > > I am using an earlier Saum A/D device that I modified slightly to have a > wider frequency response, with the modifications hopefully increasing > the high pass characteristics. I was satisfied when I could see our > local Washington quakes which have a higher frequency than the > teleseismic events. > > The sensor is the next step from the device I posted some time ago at > http://www.fairpoint.net/~sparksite/CSpring%20Seismometer.html > . > Damping is with magnetic braking. The device does not record a strictly > vertical motion because the mass axis is tilted (to improve the low > frequency response) giving a response similar to the response from the > CSpring Seismometer (which is incorrectly claimed to be a (only) > vertical sensing device). Both the CSpring device and my present device > respond to horizontal motion to the extent dictated by the vector angle > from the pivot point to the center of mass. > > Your comment about wave form seems to say that the wave forms between > your recordings and mine seem to be similar. If that is what you intend > to say, I am somewhat surprised because this station is located between > some mountains which I would (I think) cause reflections that would > change the wave form. I have wondered if amateur seismic stations could > utilize the interference rendering technique to actually map the surface > and subsurface features of the earth somewhat akin to what is done with > medical imaging? My own knowledge of imaging is too weak to venture an > opinion. > > Thanks for sharing your results. > > Roger > > psn-l-digest-request@.............. wrote: >> .------ ------ ------ ------ ------ ------ ------ ------ ------ ------. >> | Message 1 | >> '------ ------ ------ ------ ------ ------ ------ ------ ------ ------' >> Subject: WinQuake Times >> From: "Geoffrey" >> Date: Mon, 9 Nov 2009 13:37:09 -0700 >> >> Hello PSN; >> >> FYI >> I made the changes to a conversion program >> of my own to invent a PSN4 file for my data >> and wish to announce that since I have >> placed the fractional value of the start time >> times a billion into the NANO SECOND >> area the times I now get from winquake appear >> to be proper. I have tested this using >> pulse marks made by myself then gone back >> into the program and checked the times. >> The proper way would be to use WWV minute marks >> I have not yet done this however I expect for >> amateur purposes that would be correct also. >> >> I now feel I can resume sending reports >> to whoever and expect the times to be correct >> or as correct as can be for my station. >> >> GVA teleseismic events appear very close agreement >> in form to the fellow in Washington State so I am >> guessing that phase (up is up) is proper also. >> I only do an SPZ channel so can not compare >> with those using N or E sensors. >> Roger Sparks Device seems to have a lower freq >> response so our comparisons will rarely >> be exact yet they seem very close in appearance. >> >> geoff >> >> >> >> __________________________________________________________ >> >> Public Seismic Network Mailing List (PSN-L) >> >> To leave this list email PSN-L-DIGEST-REQUEST@.............. with >> the body of the message (first line only): unsubscribe >> See http://www.seismicnet.com/maillist.html for more information. >> >> > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: WinQuake Times From: Brett Nordgren brett3nt@............. Date: Wed, 11 Nov 2009 14:03:21 -0500 Geoff, Your torsion seismo is just the sort of thing that is getting quite a bit of interest in the seimo community right now--lots of papers, etc. on rotational seismology. I don't much understand most of them, but at the moment there seem to be a number of folks studying it. Only problem I can think of is that the rotational motions may be much smaller than the usual Up-Down, N-S & E-W linear motions except maybe for local quakes, but it sounds like it might be an interesting thing to look at. Best regards, Brett At 09:22 AM 11/10/2009 -0700, you wrote: >Your Setup is the very kind I like to see. > >I once made a torsion seismometer using >a spring made out of an aluminum antenna >rod split down the middle and fastened >at both ends in clamps like the scientists use. >Then it had a long lever arm of wood with a >magnet on the end. It was a hopeful dream >that never realized itself due to annoying >torments in my life. The period must have >been longer than a second. I have faith (chuckle) >in torsional kind of seismic devices. >If you made two and put them back to back >you may possibly cancel out tilt and only >look at vertical motions. But not exactly sure. >Thanks for the input Mr. Sparks, Best Regards, geoff Watch our wiggles http://bnordgren.org/seismo/gif_images.htm or watch some very very good wiggles http://aslwww.cr.usgs.gov/Seismic_Data/telemetry_data/ANMO_24hr.html __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: RE: WinQuake Times From: felipe luevanos luevanos felicaribe5@........... Date: Wed, 11 Nov 2009 20:33:35 +0000 Hello everyone=2C =20 I thought you might like this link: =20 http://www.cenews.com/news-new_inertial_mems_accelerometers_expected_to_ben= efit_infrastructure_and_seismic_monitoring-717.html =20 Kind regards=2C =20 Felipe Luevanos Fontana=2C CA =20 > Date: Wed=2C 11 Nov 2009 14:03:21 -0500 > To: psn-l@.............. > From: brett3nt@............. > Subject: Re: WinQuake Times >=20 > Geoff=2C >=20 > Your torsion seismo is just the sort of thing that is getting quite a bit= =20 > of interest in the seimo community right now--lots of papers=2C etc. on=20 > rotational seismology. I don't much understand most of them=2C but at the= =20 > moment there seem to be a number of folks studying it. Only problem I can= =20 > think of is that the rotational motions may be much smaller than the usua= l=20 > Up-Down=2C N-S & E-W linear motions except maybe for local quakes=2C but = it=20 > sounds like it might be an interesting thing to look at. >=20 > Best regards=2C > Brett >=20 > At 09:22 AM 11/10/2009 -0700=2C you wrote: > >Your Setup is the very kind I like to see. > > > >I once made a torsion seismometer using > >a spring made out of an aluminum antenna > >rod split down the middle and fastened > >at both ends in clamps like the scientists use. > >Then it had a long lever arm of wood with a > >magnet on the end. It was a hopeful dream > >that never realized itself due to annoying > >torments in my life. The period must have > >been longer than a second. I have faith (chuckle) > >in torsional kind of seismic devices. > >If you made two and put them back to back > >you may possibly cancel out tilt and only > >look at vertical motions. But not exactly sure. > >Thanks for the input Mr. Sparks=2C >=20 > >=20 > Best Regards=2C > geoff >=20 > Watch our wiggles > http://bnordgren.org/seismo/gif_images.htm >=20 > or watch some very very good wiggles > http://aslwww.cr.usgs.gov/Seismic_Data/telemetry_data/ANMO_24hr.html >=20 >=20 > __________________________________________________________ >=20 > Public Seismic Network Mailing List (PSN-L) >=20 > To leave this list email PSN-L-REQUEST@.............. with=20 > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. =20 _________________________________________________________________ Windows Live: Keep your friends up to date with what you do online. http://www.microsoft.com/middleeast/windows/windowslive/see-it-in-action/so= cial-network-basics.aspx?ocid=3DPID23461::T:WLMTAGL:ON:WL:en-xm:SI_SB_1:092= 010= Hello everyone=2C
 =3B
I thought you might like this link:
 =3B
http://www.= cenews.com/news-new_inertial_mems_accelerometers_expected_to_benefit_infras= tructure_and_seismic_monitoring-717.html
 =3B
Kind regards=2C
 =3B
Felipe Luevanos
Fontana=2C CA
 =3B
>=3B Date: Wed=2C 11 Nov 2009 14:03:21 -0500=
>=3B To: psn-l@..............
>=3B From: brett3nt@.............<= BR>>=3B Subject: Re: WinQuake Times
>=3B
>=3B Geoff=2C
>= =3B
>=3B Your torsion seismo is just the sort of thing that is gettin= g quite a bit
>=3B of interest in the seimo community right now--lots= of papers=2C etc. on
>=3B rotational seismology. I don't much unders= tand most of them=2C but at the
>=3B moment there seem to be a number= of folks studying it. Only problem I can
>=3B think of is that the r= otational motions may be much smaller than the usual
>=3B Up-Down=2C = N-S &=3B E-W linear motions except maybe for local quakes=2C but it
= >=3B sounds like it might be an interesting thing to look at.
>=3B <= BR>>=3B Best regards=2C
>=3B Brett
>=3B
>=3B At 09:22 AM = 11/10/2009 -0700=2C you wrote:
>=3B >=3BYour Setup is the very kind = I like to see.
>=3B >=3B
>=3B >=3BI once made a torsion seism= ometer using
>=3B >=3Ba spring made out of an aluminum antenna
&g= t=3B >=3Brod split down the middle and fastened
>=3B >=3Bat both e= nds in clamps like the scientists use.
>=3B >=3BThen it had a long l= ever arm of wood with a
>=3B >=3Bmagnet on the end. It was a hopeful= dream
>=3B >=3Bthat never realized itself due to annoying
>=3B= >=3Btorments in my life. The period must have
>=3B >=3Bbeen longe= r than a second. I have faith (chuckle)
>=3B >=3Bin torsional kind o= f seismic devices.
>=3B >=3BIf you made two and put them back to bac= k
>=3B >=3Byou may possibly cancel out tilt and only
>=3B >= =3Blook at vertical motions. But not exactly sure.
>=3B >=3BThanks f= or the input Mr. Sparks=2C
>=3B
>=3B <=3Bclip>=3B
>=3B =
>=3B Best Regards=2C
>=3B geoff
>=3B
>=3B Watch our w= iggles
>=3B http://bnordgren.org/seismo/gif_images.htm
>=3B
&= gt=3B or watch some very very good wiggles
>=3B http://aslwww.cr.usgs.= gov/Seismic_Data/telemetry_data/ANMO_24hr.html
>=3B
>=3B
>= =3B __________________________________________________________
>=3B >=3B Public Seismic Network Mailing List (PSN-L)
>=3B
>=3B T= o leave this list email PSN-L-REQUEST@.............. with
>=3B the bo= dy of the message (first line only): unsubscribe
>=3B See http://www.s= eismicnet.com/maillist.html for more information.

Windows Live: Keep your friends up to date with what you do online. = Subject: Re: WinQuake Times From: "Geoffrey" gmvoeth@........... Date: Wed, 11 Nov 2009 16:52:14 -0700 If the MEMS were 1000 times more sensitive then that means 2G+/- becomes 0.002G+/- And I bet that HP being an American company that does not like competition between companies ( only competition between workers) will charge X1000 whatever the old ones were :-) This means only 1/1000 the amateurs will be able to afford them. The thing that looks best here is the opportunity for a very cheap sensor that may be worthwhile in receiving seismic signals. I bet this is the thing that may go to MARS. Maybe NASA helped HP make the thing with its government supercomputers and physics peoples ??? Will the government get a piece of the action ? It would be interesting to see more of the R&D that went into the new device. ----- Original Message ----- From: "felipe luevanos luevanos" To: Sent: Wednesday, November 11, 2009 1:33 PM Subject: RE: WinQuake Times Hello everyone, I thought you might like this link: http://www.cenews.com/news-new_inertial_mems_accelerometers_expected_to_benefit_infrastructure_and_seismic_monitoring-717.html Kind regards, Felipe Luevanos Fontana, CA > Date: Wed, 11 Nov 2009 14:03:21 -0500 > To: psn-l@.............. > From: brett3nt@............. > Subject: Re: WinQuake Times > > Geoff, > > Your torsion seismo is just the sort of thing that is getting quite a bit > of interest in the seimo community right now--lots of papers, etc. on > rotational seismology. I don't much understand most of them, but at the > moment there seem to be a number of folks studying it. Only problem I can > think of is that the rotational motions may be much smaller than the usual > Up-Down, N-S & E-W linear motions except maybe for local quakes, but it > sounds like it might be an interesting thing to look at. > > Best regards, > Brett > > At 09:22 AM 11/10/2009 -0700, you wrote: > >Your Setup is the very kind I like to see. > > > >I once made a torsion seismometer using > >a spring made out of an aluminum antenna > >rod split down the middle and fastened > >at both ends in clamps like the scientists use. > >Then it had a long lever arm of wood with a > >magnet on the end. It was a hopeful dream > >that never realized itself due to annoying > >torments in my life. The period must have > >been longer than a second. I have faith (chuckle) > >in torsional kind of seismic devices. > >If you made two and put them back to back > >you may possibly cancel out tilt and only > >look at vertical motions. But not exactly sure. > >Thanks for the input Mr. Sparks, > > > > Best Regards, > geoff > > Watch our wiggles > http://bnordgren.org/seismo/gif_images.htm > > or watch some very very good wiggles > http://aslwww.cr.usgs.gov/Seismic_Data/telemetry_data/ANMO_24hr.html > > > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. _________________________________________________________________ Windows Live: Keep your friends up to date with what you do online. http://www.microsoft.com/middleeast/windows/windowslive/see-it-in-action/social-network-basics.aspx?ocid=PID23461::T:WLMTAGL:ON:WL:en-xm:SI_SB_1:092010 __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: WinQuake Times From: ChrisAtUpw@....... Date: Wed, 11 Nov 2009 22:33:04 EST In a message dated 11/11/2000, gmvoeth@........... writes: If the MEMS were 1000 times more sensitive then that means 2G+/- becomes 0.002G+/- And I bet that HP being an American company that does not like competition between companies ( only competition between workers) will charge X1000 whatever the old ones were :-) This means only 1/1000 the amateurs will be able to afford them. Hi Geoff, The good news is that HP don't make them. See _http://www.colibrys.com/e/page/140/_ (http://www.colibrys.com/e/pa ge/140/) Regards, Chris
In a message dated 11/11/2000, gmvoeth@........... writes:
If the=20 MEMS were 1000 times more sensitive
then that means 2G+/- becomes=20 0.002G+/-
And I bet that HP being an American company that
does no= t like=20 competition between companies
( only competition between workers)
= will=20 charge X1000 whatever the old ones were :-)
This means only 1/1000 th= e=20 amateurs will
be able to afford them.
Hi Geoff,
 
    The good news is that HP don't make them.
    See http://www.colibrys.com/e/pag= e/140/
 
    Regards,
 
    Chris
Subject: Re: WinQuake Times From: Mark Robinson mark.robinson@............... Date: Thu, 12 Nov 2009 17:25:17 +1300 ChrisAtUpw@....... wrote: > In a message dated 11/11/2000, gmvoeth@........... writes: > If the MEMS were 1000 times more sensitive > then that means 2G+/- becomes 0.002G+/- > And I bet that HP being an American company that > does not like competition between companies > ( only competition between workers) > will charge X1000 whatever the old ones were :-) > This means only 1/1000 the amateurs will > be able to afford them. > > Hi Geoff, > The good news is that HP don't make them. > See http://www.colibrys.com/e/page/140/ Are my calculations indicating a noise level of 1 milli-gravity at a period of 10,000,000 seconds correct ? That's just scary. Dare I wonder how much these things cost ? Cheerio Mark __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: WinQuake Times From: ChrisAtUpw@....... Date: Thu, 12 Nov 2009 02:50:21 EST In a message dated 12/11/2009, mark.robinson@............... writes: ChrisAtUpw@....... wrote: > In a message dated 11/11/2000, gmvoeth@........... writes: > If the MEMS were 1000 times more sensitive > then that means 2G+/- becomes 0.002G+/- > Hi Geoff, > The good news is that HP don't make them. > See http://www.colibrys.com/e/page/140/ Are my calculations indicating a noise level of 1 milli-gravity at a period of 10,000,000 seconds correct ? Hi Mark, Don't think so. The normal MEMS accelerometer devices have a dynamic range of about 93 dB Max, often less. The range has been extended in the newer devices to over 120 dB. They still remain basic strong motion accelerometers from +/- 3 g downwards. My interpretation the the company has at last learned to good senors Dare I wonder how much these things cost ? I suggest that you simply ask. Regards, Chrid Chapman
In a message dated 12/11/2009, mark.robinson@............... writes:<= /DIV> ChrisAtUpw@....... wrote:
> In a message dated 11/11/= 2000,=20 gmvoeth@........... writes:
>     If the MEMS were= 1000=20 times more sensitive
>     then that means 2G+/- be= comes=20 0.002G+/-
 
> Hi Geoff,
>     The goo= d news=20 is that HP don't make them.
>     See=20 http://www.colibrys.com/e/page/140/

Are my calculations indicatin= g a=20 noise level of 1 milli-gravity at a period of
10,000,000 seconds cor= rect=20 ?
Hi Mark,
 
    Don't think so.
 
    The normal  MEMS accelerometer devices= have a=20 dynamic range of about 93 dB Max, often less. The range has been=20 extended in the newer devices to over 120 dB. They still remain basic= =20 strong motion accelerometers from +/- 3 g downwards. My interpretation the= the=20 company has at last learned to good senors
Dare I=20 wonder how much these things cost ?
    I suggest that you simply ask.
 
    Regards,
 
    Chrid Chapman
Subject: Re: WinQuake Times From: Barry Lotz barry_lotz@............. Date: Thu, 12 Nov 2009 06:04:05 -0800 (PST) Mark I found a company called Sensr that sells 3 different data acquisition syst= ems for $700 up. Not really that bad when it includes a 3 axis and storage. =A0http://www.sensr.com/products/civil-and-structural/ Regards Barry --- On Wed, 11/11/09, Mark Robinson wrote: From: Mark Robinson Subject: Re: WinQuake Times To: psn-l@.............. Date: Wednesday, November 11, 2009, 8:25 PM ChrisAtUpw@....... wrote: > In a message dated 11/11/2000, gmvoeth@........... writes: >=A0 =A0=A0=A0If the MEMS were 1000 times more sensitive >=A0 =A0=A0=A0then that means 2G+/- becomes 0.002G+/- >=A0 =A0=A0=A0And I bet that HP being an American company that >=A0 =A0=A0=A0does not like competition between companies >=A0 =A0=A0=A0( only competition between workers) >=A0 =A0=A0=A0will charge X1000 whatever the old ones were :-) >=A0 =A0=A0=A0This means only 1/1000 the amateurs will >=A0 =A0=A0=A0be able to afford them. >=20 > Hi Geoff, >=A0 =A0=A0=A0The good news is that HP don't make them. >=A0 =A0=A0=A0See http://www.colibrys.com/e/page/140/ Are my calculations indicating a noise level of 1 milli-gravity at a period= of 10,000,000 seconds correct ? That's just scary. Dare I wonder how much these things cost ? Cheerio Mark __________________________________________________________ Public Seismic Network Mailing List (PSN-L)
Mark
I found a company called Sensr that s= ells 3 different data acquisition systems for $700 up. Not really that bad = when it includes a 3 axis and storage.
 http://www.sensr.com/produc= ts/civil-and-structural/
Regards
Barry


--- On Wed, 11/1= 1/09, Mark Robinson <mark.robinson@...............> wrote:=

From: Mark Robinson <mark.robinson@para= dise.net.nz>
Subject: Re: WinQuake Times
To: psn-l@..............<= br>Date: Wednesday, November 11, 2009, 8:25 PM

ChrisAtUpw@....... wrote:
> In a message dated 11/= 11/2000, gmvoeth@........... writ= es:
>     If the MEMS were 1000 times more sensit= ive
>     then that means 2G+/- becomes 0.002G+/-=
>     And I bet that HP being an American compan= y that
>     does not like competition between co= mpanies
>     ( only competition between workers)=
>     will charge X1000 whatever the old ones we= re :-)
>     This means only 1/1000 the amateurs = will
>     be able to afford them.
>
&g= t; Hi Geoff,
>     The good news is that HP don't= make them.
>     See http://www.colibrys.com/e/page/140/<= /a>

Are my calculations indicating a noise level of 1 milli-gravity at a period of 10,000,000 seconds correct ?

That's just scary.
<= br>Dare I wonder how much these things cost ?

Cheerio
Mark
__________________________________________________________

Public S= eismic Network Mailing List (PSN-L)

To leave this list email PSN-L-REQUEST@.............. with the body of t= he message (first line only): unsubscribe
See http://www.seismicnet.com/maill= ist.html for more information.
Subject: Finders Keepers ? From: "GPayton" gpayton@............. Date: Thu, 12 Nov 2009 08:21:35 -0600 Occasionally, I read about someone finding "this" or finding "that" pertaining to our hobby. I have always wondered WHERE they are finding these prizes. Excluding the R.T.Clark website and EBay, of course, I don't know where you people are finding these sensors and such. Of course, living in the quite of North Central Texas, I do not want a Strong Motion Accelerometer. Are these finds from personal contacts, websites, or where? Thanks, Jerry
Occasionally, I read about someone finding "this" or finding "that" = pertaining to our hobby.  I have always wondered WHERE they are = finding=20 these prizes.  Excluding the R.T.Clark website and EBay, of course, = I don't=20 know where you people are finding these sensors and such. 
 
Of course, living in the quite of North Central Texas, I do not = want a=20 Strong Motion Accelerometer.  Are these finds from personal = contacts,=20 websites, or where?
 
Thanks,
Jerry
Subject: FYI for you electronic types building your own stuff From: "Geoffrey" gmvoeth@........... Date: Thu, 12 Nov 2009 12:15:48 -0700 Hello PSN, For those of you interested in building your own State of the ART kind of seismometer. Here is some new info on the latest MEMS thingy. I know AVNET they are kind of expensive they seem to like to deal with small buisness peoples more than anyone else. MESSAGE SENT: Description of your request: I am interested in your new MEMS device for seismic detection as related to Earthquakes both distant (Teleseismic) and near (local or regional) Can you tell me where in Arizona or on the internet your new Sensitive MEMS accelerometer device SF3000L can be purchased ? Do you have other sensors that may be like this yet only in one axis (Z Axis is of greatest interest to myself) ? ANSWER: Dear Mr. Voeth: Thank you for your interest in Colibrys and its seismic accelerometers. We sell all our accelerometers in North America through the distributor, Avnet. Click here to go to Avnet's web-pages which alphabetically list all our accelerometer products and you can get the pricing, purchase and delivery information you require. For specific inquiries of Avnet, please contact Mr. David Moore at his email, David.Moore@.......... We do have single-axis products, SF1500 and SF2005 which can also be used for the applications you describe. Data sheets for these products can be found on our website, www,colibrys.com. Let me know if you have any additional technical questions. Best regards, Jim James A. Aberson, Ph. D. VP Sales, North America Colibrys, Inc. 8343 Roswell Rd, Suite 393 Atlanta, GA 30350 +678-585-9323 (P) +678-585-9324 (F) +919-946-0355 (M) jim.aberson@............ (Email) www.colibrys.com (Website) EOF __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: WinQuake Times From: "Geoffrey" gmvoeth@........... Date: Thu, 12 Nov 2009 12:32:52 -0700 One device indicated here in this group goes down to 0.0001G and cost like 1900 USD probably with taxes. which is cheaper than a HS-10 brand new. But I think you may want 50 feet of cable between your computer and the device located underground and yet I have not seen a device allowing 50 feet of cable. USB is not what you want. You want ETHERNET for like 50 feet of distance. Possibly with power sent to the device underground. I have yet to see any device built with ethernet communications in mind. ----- Original Message ----- From: To: Sent: Thursday, November 12, 2009 12:50 AM Subject: Re: WinQuake Times > In a message dated 12/11/2009, mark.robinson@............... writes: > > ChrisAtUpw@....... wrote: >> In a message dated 11/11/2000, gmvoeth@........... writes: >> If the MEMS were 1000 times more sensitive >> then that means 2G+/- becomes 0.002G+/- > >> Hi Geoff, >> The good news is that HP don't make them. >> See http://www.colibrys.com/e/page/140/ > > Are my calculations indicating a noise level of 1 milli-gravity at a > period of > 10,000,000 seconds correct ? > > Hi Mark, > > Don't think so. > > The normal MEMS accelerometer devices have a dynamic range of about > 93 dB Max, often less. The range has been extended in the newer devices to > over 120 dB. They still remain basic strong motion accelerometers from +/- 3 > g downwards. My interpretation the the company has at last learned to good > senors > > Dare I wonder how much these things cost ? > I suggest that you simply ask. > > Regards, > > Chrid Chapman > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Finders Keepers ? From: "Geoffrey" gmvoeth@........... Date: Thu, 12 Nov 2009 12:44:44 -0700 I have heard of two companies selling NEW velocity type sensors. One is somewhere in TEXAS selling the HS-10 for like $3000 new down to 0.75Hz If lucky you will find one used. And another in PASADENA california selling a similar device. I really like the HS10 but not the price. As one of the little people $3000 may as well be $3,000,000 :-) The best alternative is to build your own or buy from a third party catering to educators. Im not sure Larry sells the geophone part but he does the electronics. Maybe he will include new technology like one of these MEMS thingys in the future ? But Acceleration gives you an odd picture compared with velocity or actual displacement. I think you can use calculus in a program to convert between acceleration and other forms of the very same data but not sure. So like maybe you record acceleration then convert your data to whatever else. Scribblings of a locos gringos. geoff ----- Original Message ----- From: "GPayton" To: Sent: Thursday, November 12, 2009 7:21 AM Subject: Finders Keepers ? > Occasionally, I read about someone finding "this" or finding "that" > pertaining to our hobby. I have always wondered WHERE they are finding > these prizes. Excluding the R.T.Clark website and EBay, of course, I don't > know where you people are finding these sensors and such. > > Of course, living in the quite of North Central Texas, I do not want a > Strong Motion Accelerometer. Are these finds from personal contacts, > websites, or where? > > Thanks, > Jerry > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: How Does This Grab You From: "Geoffrey" gmvoeth@........... Date: Thu, 12 Nov 2009 13:02:51 -0700 Its like $1800 for one of those decent MEMS thingys. I think your better off building your own till the price comes down. http://avnetexpress.avnet.com/store/em/EMController?langId=-1&storeId=500201&catalogId=500201&term=SF3000L%2Baccelerometer&N=0&action=products&x=8&y=11 __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: WinQuake Times From: ChrisAtUpw@....... Date: Thu, 12 Nov 2009 20:11:11 EST In a message dated 12/11/2009, barry_lotz@............. writes: I found a company called Sensr that sells 3 different data acquisition systems for $700 up. Not really that bad when it includes a 3 axis and storage. http://www.sensr.com/products/civil-and-structural/ Regards Barry Hi Barry, These are commercial MEMs units with a range of 12 g to 0.05 g and 0.001 g resolution. These are fine for making environmental measurements on bridges, buildings, etc., but you need to be able to measure to micro g levels for a strong motion seismometer, whether professional or amateur. Larry sells a 3 axis strong motion accelerometer board with serial amplifiers giving ranges of 2 g and 70 milli g maximum, driving a 16 bit ADC. These give 6-9 mV / g and 1 micro V p-p noise. The ADXL103/203 have a range of +/-1.7 g and a noise level of 110 micro g / root Hz rms. For 20 Hz bandwidth the noise is about 0.7 milli g pk. You are relatively unlikely to observe quakes with these unless you live over an area of known seismic activity. Colibrys _http://www.colibrys.com/e/page/140/_ (http://www.colibrys.com/e/page/140/) offer a +/3 g range and 300 nano g rms / root Hz noise. However, Avnet seem to have an unrealistic idea of the value of this sensor. I note that they are not stocking them at the moment. I have used piezo disks from _www.digikey.com_ (http://www.digikey.com) 102-1170-ND at $1.62 and 668-1190-ND at $2.72 as accelerometers. Used in simple bending mode supported on two sides (NOT as a circular diaphragm), with a central 1 oz mass on a square brass tube support (_http://www.ksmetals.com/_ (http://www.ksmetals.com/) ) and a FET input amplifier, they can sense right down to the seismic background noise level. They need to be kept dry at all times and temperature variations need to be reduced as far as possible. I mount one with the amplifier in a glass jam jar with a rubber seal metal lid and use a disk of circuit board with feed through soldered pins. There is a lot more information available at _http://jclahr.com/science/psn/chapman/piezo/index.html_ (http://jclahr.com/science/psn/chapman/piezo/index.html) You may feel quakes over about 0.015 g. Regards, Chris Chapman
In a message dated 12/11/2009, barry_lotz@............. writes:
I= found a=20 company called Sensr that sells 3 different data acquisition systems for= $700=20 up. Not really that bad when it includes a 3 axis and=20 storage.
 http://www.sensr.com/products/civil-and-structural/Regards
Barry
Hi Barry,
 
    These are commercial MEMs units with a range= of 12=20 g to 0.05 g and 0.001 g resolution. These are fine for making environmenta= l=20 measurements on bridges, buildings, etc., but you need to be able to measu= re to=20 micro g levels for a strong motion seismometer, whether professional or am= ateur.=20
    Larry sells a 3 axis strong motion accelerome= ter=20 board with serial amplifiers giving ranges of 2 g and 70 milli g maxi= mum,=20 driving a 16 bit ADC. These give 6-9 mV / g and 1 micro V p-p noise.
    The ADXL103/203 have a range of +/-1.7= g and a=20 noise level of 110 micro g / root Hz rms. For 20 Hz bandwidth the noise is= about=20 0.7 milli g pk. You are relatively unlikely to observe quakes with these= unless=20 you live over an area of known seismic activity.  
    Colibrys http://www.colibrys.com/e/pag= e/140/ offer=20 a +/3 g range and 300 nano g rms / root Hz noise. However, Avnet seem to= have an=20 unrealistic idea of the value of this sensor. I note that they are not sto= cking=20 them at the moment.
    I have used piezo disks from www.digikey.com 102-1170-ND at $1.62= and=20 668-1190-ND at $2.72 as accelerometers. Used in simple bending mode suppor= ted on=20 two sides (NOT as a circular diaphragm),  with a central 1 oz mass on= a=20 square brass tube support (http://www.ksmetals.com/) and a= FET=20 input amplifier, they can sense right down to the seismic background noise= =20 level. They need to be kept dry at all times and temperature variations ne= ed to=20 be reduced as far as possible.  I mount one with the amplifier in a= glass=20 jam jar with a rubber seal metal lid and use a disk of circuit board= with=20 feed through soldered pins. There is a lot more information available at= http://jcl= ahr.com/science/psn/chapman/piezo/index.html
    You may feel quakes over about 0.015 g.
 
    Regards,
 
    Chris Chapman
Subject: Re: Finders Keepers ? From: Larry Cochrane lcochrane@.............. Date: Fri, 13 Nov 2009 16:38:26 -0800 Geoffrey wrote: > I have heard of two companies selling > NEW velocity type sensors. > > One is somewhere in TEXAS selling the HS-10 > for like $3000 new down to 0.75Hz > If lucky you will find one used. > > And another in PASADENA california selling a similar device. > > I really like the HS10 but not the price. > As one of the little people $3000 may as well > be $3,000,000 :-) > > > The best alternative is to build your own or > buy from a third party catering to educators. > Im not sure Larry sells the geophone part > but he does the electronics. Maybe he will > include new technology like one of these MEMS > thingys in the future ? Not at $1800.00 each! Maybe someday when the price drops to under $300.00 in quantities of 100 or less. > But Acceleration gives you an odd picture > compared with velocity or actual displacement. > I think you can use calculus in a program to convert between > acceleration and other forms of the very same data > but not sure. So like maybe you record acceleration > then convert your data to whatever else. One of the features in WinQuake is Integration. When you integrate data from an accelerometer you will get velocity and if you integrate once more you get displacement. Regards, Larry Cochrane Redwood City, PSN __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Finders Keepers ? From: ChrisAtUpw@....... Date: Fri, 13 Nov 2009 23:04:03 EST In a message dated 14/11/2009, lcochrane@.............. writes: > The best alternative is to build your own or buy from a third party catering to educators. > Im not sure Larry sells the geophone part but he does the electronics. Hi Geoff, You may have to wait until Larry gets around to producing a 24 bit ADC. With a 3 g maximum, a 16 bit ADC has a minimum step size of 92 micro g. > Maybe he will include new technology like one of these MEMS > thingys in the future ? Larry already sells the ICS 3052 accelerometer board. Not at $1800.00 each! Maybe someday when the price drops to under $300.00 in quantities of 100 or less. Er? Let's make that $40? Looks like we are in for a severe shake up in the seismic accelerometer market. Check out the offerings from DigiKey? You can also get MEMs with an integral ADC. Regards, Chris Chapman
In a message dated 14/11/2009, lcochrane@.............. writes:
> The=20 best alternative is to build your own or buy from a third party catering= to=20 educators.
> Im not sure Larry sells the geophone part but he= does=20 the electronics.
Hi Geoff,
    
    You may have to wait until Larry gets ar= ound=20 to producing a 24 bit ADC. With a 3 g maximum, a 16 bit ADC has a minimum= step=20 size of 92 micro g. 
>=20 Maybe he will include new technology like one of these MEMS
>= =20 thingys in the future ?
    Larry already sells the ICS 3052 acceleromete= r=20 board.
Not at=20 $1800.00 each! Maybe someday when the price drops to under $300.00 in=20
quantities of 100 or less.
    Er? Let's make that $40?

 
    Looks like we are in for a severe shake up in= the=20 seismic accelerometer market.
    Check out the offerings from DigiKey? You can= also=20 get MEMs with an integral ADC.
 
    Regards,
 
    Chris Chapman
Subject: Re: Finders Keepers ? From: Mauro Mariotti mariotti@......... Date: Sat, 14 Nov 2009 08:23:17 +0100 Hi Jerry, Geospace in Huston sells exploration geophones you can also find something in China from Senshe Sercel (also in texas) sells geophones. In holland there is the I/O company that manufacture geophones. I think they can sell you some samples. costs for samples are usually around 100-200 $ per item 4.5Hz and 200-400 $ for 2Hz sensors. MEMS accelerometer still tobe not sensitive enough for weak motions. regards mauro At 15:21 12/11/2009, you wrote: >Occasionally, I read about someone finding "this" or finding "that" >pertaining to our hobby. I have always wondered WHERE they are >finding these prizes. Excluding the R.T.Clark website and EBay, of >course, I don't know where you people are finding these sensors and such. > >Of course, living in the quite of North Central Texas, I do not want >a Strong Motion Accelerometer. Are these finds from personal >contacts, websites, or where? > >Thanks, >Jerry __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Remote monitoring From: Barry Lotz barry_lotz@............. Date: Tue, 17 Nov 2009 18:58:36 -0800 (PST) Hi All A colleague at work informed me of another means to remotely controlling or= monitor your computer (seismic program)=A0 from=A0 elsewhere: www.logmein.= com=A0 . It works well and requires minimal knowledge of internet/networkin= g parameters, and it's free. I was able to level or reposition my sensor fr= om work.=20 Barry =A0
Hi All
A colleague at work informed me of = another means to remotely controlling or monitor your computer (seismic pro= gram)  from  elsewhere: www.logmein.com  . It works well and= requires minimal knowledge of internet/networking parameters, and it's fre= e. I was able to level or reposition my sensor from work.
Barry
&nbs= p;
Subject: Re: Remote monitoring From: ian ian@........... Date: Wed, 18 Nov 2009 08:16:02 +0000 I've used the free version of VNC for many years to control my seismo pc. http://www.realvnc.com/products/free/4.1/download.html Ian Barry Lotz wrote: > Hi All > A colleague at work informed me of another means to remotely > controlling or monitor your computer (seismic program) from > elsewhere: www.logmein.com . It works well and requires minimal > knowledge of internet/networking parameters, and it's free. I was able > to level or reposition my sensor from work. > Barry > > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Remote monitoring From: Thomas Dick dickthomas01@............. Date: Wed, 18 Nov 2009 09:11:08 -0600 Barry Lotz wrote: > Hi All > A colleague at work informed me of another means to remotely > controlling or monitor your computer (seismic program) from > elsewhere: www.logmein.com . It works well and requires minimal > knowledge of internet/networking parameters, and it's free. I was able > to level or reposition my sensor from work. > Barry > > I, too, have used VNC for a long time. It works very well within my small network of five desktops and three laptops; some attached via cable and others WiFi. For a long time, I had no problems accessing my earthquake computer with a laptop when visiting my children or even at hotels and campgrounds. However, Insight has begun to change IP addresses to curb personal web sites. This is a hindrance. A good programmer can work around this my son tells me. I don't have the expertize myself, however, one of my laptops still works thanks to tech service. I talked to Insight about remote accessing my earthquake computer. The tech said it was OK for what I was doing. Also, I came acrossed one problem that might might interest some. I guess the present earthquake computer has been on for over two years. Recently I lost color presentation on the monitors that weren't immediately attached to the desktop computer that runs WinSDR. My son suggested that I shut down VNC and restart the earthquake computer. This solved the problem. Interesting, too, I have one laptop that has the newest version of VNC on it and it displayed the correct coloration the whole time. __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Remote monitoring From: Barry Lotz barry_lotz@............. Date: Wed, 18 Nov 2009 18:13:05 -0800 (PST) Ian & Thomas I had used Tightvnc for awhile and it worked well for my home network. I di= d begin to have problems when trying from outside my network. I also notice= d that VNC didn't update my winsdr monitor screen til I clicked the mouse. = logmein shows the moving screen. The only draw back I've found with logmein= so far is it takes a little longer to access my computer from within my ho= me network than vnc. Barry . --- On Wed, 11/18/09, ian wrote: From: ian Subject: Re: Remote monitoring To: psn-l@.............. Date: Wednesday, November 18, 2009, 12:16 AM I've used the free version of VNC for many years to control my seismo pc.= =A0 http://www.realvnc.com/products/free/4.1/download.html Ian Barry Lotz wrote: > Hi All > A colleague at work informed me of another means to remotely controlling = or monitor your computer (seismic program)=A0 from=A0 elsewhere: www.logmei= n.com=A0 . It works well and requires=0A minimal knowledge of internet/netw= orking parameters, and it's free. I was able to level or reposition my sens= or from work. > Barry >=A0=20 __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: EVENT FILE GENERATION From GVA (NOTES) From: "Geoffrey" gmvoeth@........... Date: Fri, 20 Nov 2009 22:22:26 -0700 Hello PSN; Note about GVA Winquake event files: Last WINQUAKE files I uploaded to the server had errors in the headers. I have since tried to correct this and hope they are now foerever gone. You will see unwanted characters in the TEXT since i have had a very hard time aligning everything to be correct within Winquake. Note about GVA TIMES read from Within Winquake: I am using a new scheme to correct my data times. I generate a false leadin to the data to compensate for the fractional time values. This has been the ONLY way I can look at the very first sample and get within +/- 55 milliseconds for the first displayed sample. You will see in my records a zero baseline till you get to the first actual sample deviating plus or minus. That zero baseline represents the fractional time difference away from the exact second mark. As close as I could discreetly/logically be. The time for that sample should read from WINQUAKE very close to what i read from my own sources. The ONLY way I know to do better requires a complete rewrite of the recording program to align my calibration mark with the very first record sample to exactly match the times. And i am not yet ready to do that. I have set within the winquake header file all time offsets to be equal to zero. I call it close enough for layman until further notice. :-) It took me a MOLE of versions to get this close to right. Have a nice day, GVA __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: WinQuake Times From: Barry Lotz barry_lotz@............. Date: Sun, 22 Nov 2009 07:16:25 -0800 (PST) Chris I had thought of a piezo in the past but got confused with it's output. I b= elieve it measures the rate of change of movement of the sensor. Since an a= ccelerometer gives acceleration results when measuring deflection, Does one= have to integrate piezo output results to get acceleration? Regards Barry --- On Thu, 11/12/09, ChrisAtUpw@....... wrote: From: ChrisAtUpw@....... Subject: Re: WinQuake Times To: psn-l@.............. Date: Thursday, November 12, 2009, 5:11 PM =0A=0A =0A=0A=0AIn a message dated 12/11/2009, barry_lotz@............. wri= tes:=0AI found a =0A company called Sensr that sells 3 different data acqu= isition systems for $700 =0A up. Not really that bad when it includes a 3 = axis and =0A storage. =A0http://www.sensr.com/products/civil-and-structural/ Regards Barry =0A=0AHi Barry,=0A=A0=0A=A0=A0=A0=A0These are commercial MEMs units with a = range of 12 =0Ag to 0.05 g and 0.001 g resolution. These are fine for makin= g environmental =0Ameasurements on bridges, buildings, etc., but you need t= o be able to measure to =0Amicro g levels for a strong motion seismometer, = whether professional or amateur. =0A=0A=A0=A0=A0=A0Larry sells a 3 axis str= ong motion accelerometer =0Aboard with serial amplifiers giving=A0ranges of= 2 g and 70 milli g maximum, =0Adriving a 16 bit ADC. These give 6-9 mV / g= and 1 micro V p-p noise.=0A=A0=A0=A0=A0The ADXL103/203 have=A0a range of += /-1.7 g and a =0Anoise level of 110 micro g / root Hz rms. For 20 Hz bandwi= dth the noise is about =0A0.7 milli g pk. You are relatively unlikely to ob= serve quakes with these unless =0Ayou live over an area of known seismic ac= tivity.=A0=A0=0A=A0=A0=A0=A0Colibrys http://www.colibrys.com/e/page/140/=A0= offer =0Aa +/3 g range and 300 nano g rms / root Hz noise. However, Avnet s= eem to have an =0Aunrealistic idea of the value of this sensor. I note that= they are not stocking =0Athem at the moment.=0A=A0=A0=A0=A0I have used pie= zo disks from www.digikey.com 102-1170-ND at $1.62 and =0A668-1190-ND at $2= ..72 as accelerometers. Used in simple bending mode supported on =0Atwo side= s (NOT as a circular diaphragm),=A0 with a central 1 oz mass on a =0Asquare= brass tube support=A0(http://www.ksmetals.com/) and=A0a FET =0Ainput ampli= fier, they can sense right down to the seismic background noise =0Alevel. T= hey need to be kept dry at all times and temperature variations need to =0A= be reduced as far as possible.=A0 I mount one with the amplifier in a glass= =0Ajam=A0jar with a rubber seal metal lid and use a disk of circuit board = with =0Afeed through soldered pins. There is a lot more information availab= le at http://jclahr.com/science/psn/chapman/piezo/index.html=0A=A0=A0=A0=A0= You may feel quakes over about 0.015 g.=0A=A0=0A=A0=A0=A0=A0Regards,=0A=A0= =0A=A0=A0=A0=A0Chris Chapman
Ian & ThomasI had used Tightvnc for awhile and it worked well for my home network. I d= id begin to have problems when trying from outside my network. I also notic= ed that VNC didn't update my winsdr monitor screen til I clicked the mouse.= logmein shows the moving screen. The only draw back I've found with logmei= n so far is it takes a little longer to access my computer from within my h= ome network than vnc.
Barry
.

--- On Wed, 11/18/09, ian = <ian@...........> wrote:

From= : ian <ian@...........>
Subject: Re: Remote monitoring
To: psn-= l@..............
Date: Wednesday, November 18, 2009, 12:16 AM

I've used the free version of VNC for many years to c= ontrol my seismo pc.  http://www.realvnc.com/product= s/free/4.1/download.html

Ian

Barry Lotz wrote:
> Hi= All
> A colleague at work informed me of another means to remotely c= ontrolling or monitor your computer (seismic program)  from  else= where: www.logmein.com  . It works well and requires=0A minimal knowle= dge of internet/networking parameters, and it's free. I was able to level o= r reposition my sensor from work.
> Barry
> 
_________= _________________________________________________

Public Seismic Net= work Mailing List (PSN-L)

To leave this list email PSN-L-REQUEST@.............. with the body of the message (first lin= e only): unsubscribe
See http://www.seismicnet.com/maillist.= html for more information.
Chris
I had thought of a piezo in the past= but got confused with it's output. I believe it measures the rate of chang= e of movement of the sensor. Since an accelerometer gives acceleration resu= lts when measuring deflection, Does one have to integrate piezo output resu= lts to get acceleration?
Regards
Barry

--- On Thu, 11/12/09= , ChrisAtUpw@....... <ChrisAtUpw@.......> wrote:

From: ChrisAtUpw@....... <ChrisAtUpw@.......><= br>Subject: Re: WinQuake Times
To: psn-l@..............
Date: Thursda= y, November 12, 2009, 5:11 PM

=0A=0A =0A=0A=0A
In a message dated 12/11/2009, barry_lotz@............. writes:=0A
I found a =0A company called Sensr that sells 3 di= fferent data acquisition systems for $700 =0A up. Not really that bad when= it includes a 3 axis and =0A storage.
 http://www.sensr.com/produ= cts/civil-and-structural/
Regards
Barry
= =0A
=0A
Hi Barry,
=0A
 
=0A
 &nbs= p;  These are commercial MEMs units with a range of 12 =0Ag to 0.= 05 g and 0.001 g resolution. These are fine for making environmental =0Amea= surements on bridges, buildings, etc., but you need to be able to measure t= o =0Amicro g levels for a strong motion seismometer, whether professional o= r amateur. =0A
=0A
    Larry sells a 3 axis st= rong motion accelerometer =0Aboard with serial amplifiers giving range= s of 2 g and 70 milli g maximum, =0Adriving a 16 bit ADC. These give 6-9 mV= / g and 1 micro V p-p noise.
=0A
    The ADXL= 103/203 have a range of +/-1.7 g and a =0Anoise level of 110 micro g /= root Hz rms. For 20 Hz bandwidth the noise is about =0A0.7 milli g pk. You= are relatively unlikely to observe quakes with these unless =0Ayou live ov= er an area of known seismic activity.  
=0A
  =   Colibrys http://www.colibrys.com/e/page/140/ o= ffer =0Aa +/3 g range and 300 nano g rms / root Hz noise. However, Avnet se= em to have an =0Aunrealistic idea of the value of this sensor. I note that = they are not stocking =0Athem at the moment.
=0A
   = ; I have used piezo disks from www.digikey.com 102-1170-ND at $1.62 and= =0A668-1190-ND at $2.72 as accelerometers. Used in simple bending mode sup= ported on =0Atwo sides (NOT as a circular diaphragm),  with a central = 1 oz mass on a =0Asquare brass tube support (http://www.ksmetals.com/= ) and a FET =0Ainput amplifier, they can sense right down to the seism= ic background noise =0Alevel. They need to be kept dry at all times and tem= perature variations need to =0Abe reduced as far as possible.  I mount= one with the amplifier in a glass =0Ajam jar with a rubber seal metal= lid and use a disk of circuit board with =0Afeed through soldered pins. Th= ere is a lot more information available at http:= //jclahr.com/science/psn/chapman/piezo/index.html
=0A
 &n= bsp;  You may feel quakes over about 0.015 g.
=0A
 =
=0A
    Regards,
=0A
 
=0A=
    Chris Chapman
<= /td>
Subject: Re: WinQuake Times From: ChrisAtUpw@....... Date: Sun, 22 Nov 2009 13:10:54 EST In a message dated 22/11/2009, barry_lotz@............. writes: Chris I had thought of a piezo in the past but got confused with it's output. I believe it measures the rate of change of movement of the sensor. Since an accelerometer gives acceleration results when measuring deflection, Does one have to integrate piezo output results to get acceleration? Hi Barry, The MEMs accelerometers give a direct acceleration output which includes accelerations which are constant with time. The usual way to calibrate them is to take a DC reading, invert the device and take another reading = 2g change. The piezo capacitor disks give a voltage output which is ~linear with the short period stress change (bending), so long as you support them on two sides and not as a diaphragm supported around the periphery. The disks quoted have a capacity of ~65 nF in parallel with the amplifier input resistance. This may be made 50 Meg Ohms to extend the operation out to 20 seconds - see my circuit. These are basically AC devices with a very extended decay time. _http://jclahr.com/science/psn/chapman/piezo/index.html_ (http://jclahr.com/science/psn/chapman/piezo/index.html) The voltage output of a mass loaded disk will be proportional to acceleration, but this will not include any constant acceleration. If you integrate the output, you will get a velocity for all periods less than 20 seconds. Since the amplifier input impedance is so high, you have to keep the element dry to minimise any leakage currents. But you can also varnish it. The PZT element has an appreciable voltage / temperature coefficient, so you need to minimise any temperature changes. Do always include the voltage protection diodes on the amplifier input and short circuit a disk before connecting it up. An unconnected disk may have 100 V on it due to previous temperature changes - this can blow the input of an unprotected opamp. I mount the sensor and amplifier inside a glass jar with a metal lid having a rubber seal. I cut a hole in the lid and stick on a disk of circuit board having soldered feed through pins for the supply and output connection leads. I put a small sachet of silica gel inside to keep it dry. I hope that this helps, Chris Chapman
In a message dated 22/11/2009, barry_lotz@............. writes:
Chris
I had thought of a piezo in the past but= got=20 confused with it's output. I believe it measures the rate of chang= e of=20 movement of the sensor. Since an accelerometer gives acceleration= =20 results when measuring deflection, Does one have to integrate piez= o=20 output results to get=20 acceleration?
Hi Barry,
 
    The MEMs accelerometers give a direct acceler= ation=20 output which includes accelerations which are constant with time. The usua= l way=20 to calibrate them is to take a DC reading, invert the device and take anot= her=20 reading =3D 2g change.
 
    The piezo capacitor disks give a voltage outp= ut=20 which is ~linear with the short period stress change (bending), so lo= ng as=20 you support them on two sides and not as a diaphragm supported around the= =20 periphery. The disks quoted have a capacity of ~65 nF in parallel with the= =20 amplifier input resistance. This may be made 50 Meg Ohms to extend the ope= ration=20 out to 20 seconds - see my circuit. These are basically AC devices with a= =20 very extended decay time. http://jclahr.com/science/psn/chapman/piezo/index.html=  
    The voltage output of a mass loaded disk = ;will=20 be proportional to acceleration, but this will not include any= =20 constant acceleration. If you integrate the output, you will get a velocit= y for=20 all periods less than 20 seconds.
    Since the amplifier input impedance is so hig= h, you=20 have to keep the element dry to minimise any leakage currents. But you can= also=20 varnish it. The PZT element has an appreciable voltage / tempera= ture=20 coefficient, so you need to minimise any temperature changes. 
    Do always include the voltage protection diod= es on=20 the amplifier input and short circuit a disk before connecting it up. An= =20 unconnected disk may have 100 V on it due to previous temperature changes= - this=20 can blow the input of an unprotected opamp.
    I mount the sensor and amplifier inside a gla= ss jar=20 with a metal lid having a rubber seal. I cut a hole in the lid and st= ick on=20 a disk of circuit board having soldered feed through pins for the supply= and=20 output connection leads. I put a small sachet of silica gel inside to keep= it=20 dry.
 
    I hope that this helps,
 
    Chris Chapman
Subject: Integrating in WinQuake From: RSparks rsparks@.......... Date: Sun, 22 Nov 2009 12:50:35 -0800 Hello Larry, I will begin by saying thanks for making WinQuake available to all us amateur seismometer makers. It is a great program that greatly enriches the hobby. For some reason, I got to thinking about the difference between acceleration and velocity detectors today, maybe prompted by your comment (a few days ago) about using WinQuake to double integrate the data to convert acceleration data to displacement data. The problem is that WinQuake (so far as I can determine) does not allow double integration of the data. Only one integration operation is allowed. Why does this matter? Until today, I had concluded that my magnet-coil detection system was a velocity system that only needs one integration to convert to displacement. But today I thought about what happens if my seismometer (a vertical) was placed on a rocket that boosted to a steady velocity. My seismometer would only detect the acceleration, not the steady state velocity. Hence, my detector must be an acceleration device. Thus I have a logical reason to do the second integration of data. I have tried to devise a work-around but apparently Winquake looks at the data operations recorded on the data file and locks out further integration if one has already been performed. Thanks in advance for any comments, Roger __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Integrating in WinQuake From: ChrisAtUpw@....... Date: Sun, 22 Nov 2009 19:22:18 EST In a message dated 22/11/2009, rsparks@.......... writes: For some reason, I got to thinking about the difference between acceleration and velocity detectors today, maybe prompted by your comment (a few days ago) about using WinQuake to double integrate the data to convert acceleration data to displacement data. The problem is that WinQuake (so far as I can determine) does not allow double integration of the data. Only one integration operation is allowed. Hi Roger, Have you checked Prof Wielandt's graphs of the various output systems on psn? Why does this matter? Until today, I had concluded that my magnet-coil detection system was a velocity system that only needs one integration to convert to displacement. But today I thought about what happens if my seismometer (a vertical) was placed on a rocket that boosted to a steady velocity. My seismometer would only detect the acceleration, not the steady state velocity. Hence, my detector must be an acceleration device. Thus I have a logical reason to do the second integration of data. Are you confusing detectors which have 'DC' as well as 'AC' sensitivity, with 'AC' only detectors? Your mass tries to stay stationary. If you give the frame a small velocity, the coil moves in the magnetic field giving an output proportional to that velocity. Regards, Chris Chapman
In a message dated 22/11/2009, rsparks@.......... writes:
For some=20 reason, I got to thinking about the difference between
acceleration= and=20 velocity detectors today, maybe prompted by your
comment (a few days= ago)=20 about using WinQuake to double integrate the
data to convert acceler= ation=20 data to displacement data.  The problem is
that WinQuake (so fa= r as I=20 can determine) does not allow double
integration of the data. = Only=20 one integration operation is allowed.
Hi Roger,
 
    Have you checked Prof Wielandt's graphs of th= e=20 various output systems on psn?
    Why does this matter?  Until today,= I had=20 concluded that my
magnet-coil detection system was a velocity system= that=20 only needs one
integration to convert to displacement.  But tod= ay I=20 thought about what
happens if my seismometer (a vertical) was placed= on a=20 rocket that
boosted to a steady velocity.  My seismometer would= only=20 detect the
acceleration, not the steady state velocity.  Hence,= my=20 detector must be
an acceleration device.  Thus I have a logical= =20 reason to do the second
integration of data.
    Are you confusing detectors which have 'DC'= as well=20 as 'AC' sensitivity, with 'AC' only detectors?
 
    Your mass tries to stay stationary. If you gi= ve the=20 frame a small velocity, the coil moves in the magnetic field giving an out= put=20 proportional to that velocity.
 
    Regards,
 
    Chris Chapman
Subject: Re: Integrating in WinQuake From: "Geoffrey" gmvoeth@........... Date: Sun, 22 Nov 2009 18:06:46 -0700 Velocity = FT/SEC ACCELERATION = FT/SEC^2 DISPLACEMENT = FT Seems to me like it may be simple to convert between these various forms ----- Original Message ----- From: To: Sent: Sunday, November 22, 2009 5:22 PM Subject: Re: Integrating in WinQuake > In a message dated 22/11/2009, rsparks@.......... writes: > > For some reason, I got to thinking about the difference between > acceleration and velocity detectors today, maybe prompted by your > comment (a few days ago) about using WinQuake to double integrate the > data to convert acceleration data to displacement data. The problem is > that WinQuake (so far as I can determine) does not allow double > integration of the data. Only one integration operation is allowed. > Hi Roger, > > Have you checked Prof Wielandt's graphs of the various output systems > on psn? > > Why does this matter? Until today, I had concluded that my > magnet-coil detection system was a velocity system that only needs one > integration to convert to displacement. But today I thought about what > happens if my seismometer (a vertical) was placed on a rocket that > boosted to a steady velocity. My seismometer would only detect the > acceleration, not the steady state velocity. Hence, my detector must be > an acceleration device. Thus I have a logical reason to do the second > integration of data. > > > Are you confusing detectors which have 'DC' as well as 'AC' sensitivity, > with 'AC' only detectors? > > Your mass tries to stay stationary. If you give the frame a small > velocity, the coil moves in the magnetic field giving an output proportional to > that velocity. > > Regards, > > Chris Chapman > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: WinQuake integration From: Robert McClure bobmcclure90@......... Date: Sun, 22 Nov 2009 21:28:41 -0500 If you set the original data type to acceleration, WinQuake allows you to integrate twice, but you are not likely to be pleased with what you get, unless the DC level of the data is very stable. Roger Sparks wrote: For some reason, I got to thinking about the difference between acceleration and velocity detectors today, maybe prompted by your comment (a few days ago) about using WinQuake to double integrate the data to convert acceleration data to displacement data. The problem is that WinQuake (so far as I can determine) does not allow double integration of the data. Only one integration operation is allowed. __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Integrating in WinQuake From: RSparks rsparks@.......... Date: Mon, 23 Nov 2009 15:04:02 -0800 Thanks to all who replied to my query. Bob, you were exactly right. As you might remember, I am using a tweaked version of Amaseis. One of the tweaks is the ability to generate a PSN file customized to my location with automatic naming of the file. All I needed to do was to change my hard coded description of my seismometer from velocity to acceleration. Then WinQuake recognized the file as describing an acceleration device and allowed double integration. Thanks for the advice. Chris, the link through John Lahr's PSN site to Prof Wielandt's materials no longer works. I did find what is apparently his new site at this address http://www.geophys.uni-stuttgart.de/~erhard/downloads/ but did not take time to search for his graphs that you mention. There seems to be an ongoing difference of opinion of what constitutes a velocity detector or an acceleration detector. To my mind, if a seismometer automatically returns to a zero position, then it must be recording acceleration. All vertical seismometers do this because they all are measuring against gravity, so they would all be acceleration devices. Excepting the sensitivity to tilt, all horizontal seismometers also return to a zero position so they could also be called acceleration sensitive devices. But maybe this description oversimplifies the situation. Some sensors (capacitive and optical for example) clearly record displacement (neither acceleration or velocity). On the other hand, with magnetic/coil devices, velocity is always observed when electrical output is observed so magnetic/coil devices are velocity detectors. Following the formula's given by Geoffrey, if there is displacement, there must have been velocity, and if velocity, there must have been acceleration at some time in the past. All this said, the best we can do with a seismometer is to detect motion against a floating mass which in turn moves as a result of the action of detection and carried over velocity from past accelerations. A displacement sensor would record the relative distance from a some zero point at the instant of data read, the velocity sensor would record the relative velocity at the instant of data read, and acceleration would be a calculated number found by using the data from any two velocity data points and any three displacement data points. Finally, if two seismometers, identical except for detectors, were placed side by side, they would both plot the identical earthquake wave form, assuming that the frequency characteristics were the same. However, when it is recognized that displacement position is not time sensitive but velocity is, the builder can expect dramatic frequency response differences between displacement detectors and velocity detectors . Simply put, distance is distance, but velocity is the distance divided by the time needed to travel between two points. As a result, for velocity detectors, the longer the wave length, the less energy for each instant resulting in decreased voltage (and current) detected at each instant (for any defined magnetic field). It is easy to see why there might be differences of as to type of detector in use and how to best put the resulting data to use. Roger __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: 11/23 From: "Edward Ianni" edwianni1@........... Date: Tue, 24 Nov 2009 00:54:27 +0000 Seismometer on ebay # 190352038602
Seismometer on ebay # 190352038602
Subject: Re: Integrating in WinQuake From: Brett Nordgren brett3nt@............. Date: Mon, 23 Nov 2009 20:06:51 -0500 Roger, Maybe I can help confuse the issue a bit more. You can not say that a ground motion is only a displacement, or a velocity, or an acceleration, it is always all three. A ground motion can be perfectly described by recording its displacement or its velocity or its acceleration over a period of time. If you know any one, you can exactly compute the other two by taking the integral or derivative of the recorded signal, as required. Likewise seismic detectors don't just detect displacement or velocity or acceleration. They always detect all three. For example, what is actually meant by a Velocity Sensor is one which is "Flat to Velocity" that is, it responds the same to sinusoidal ground motions having the same velocities, regardless of their frequencies. To ground motions having the same accelerations, it will respond differently at different frequencies, and similarly with ground motions having the same displacements. Some sensors are by their nature flat to velocity or to displacement or acceleration. A capacitance sensor tends to be flat to displacement, a coil and magnet is generally flat to velocity, and a MEMS accelerometer is relatively flat to acceleration (within their respective operating frequency ranges). You can even use one type of sensor to construct an instrument which responds like another. In the feedback vertical, even though we start with a capacitance sensor whose response is flat to displacement, the feedback electronics can roughly be thought of as differentiating that signal to arrive at an instrument which has a response that is generally flat to velocity. Regards, Brett Watch our wiggles http://bnordgren.org/seismo/gif_images.htm or watch some very very good wiggles http://aslwww.cr.usgs.gov/Seismic_Data/telemetry_data/ANMO_24hr.html __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Integrating in WinQuake From: ChrisAtUpw@....... Date: Mon, 23 Nov 2009 21:09:20 EST In a message dated 23/11/2009, rsparks@.......... writes: There seems to be an ongoing difference of opinion of what constitutes a velocity detector or an acceleration detector. To my mind, if a seismometer automatically returns to a zero position, then it must be recording acceleration. All vertical seismometers do this because they all are measuring against gravity, so they would all be acceleration devices. Excepting the sensitivity to tilt, all horizontal seismometers also return to a zero position so they could also be called acceleration sensitive devices. But maybe this description oversimplifies the situation. Hi Roger, Sorry, but no. You seem to be confusing devices which have AC and DC characteristics. Some sensors (capacitive and optical for example) clearly record displacement (neither acceleration or velocity). Agreed. On the other hand, with magnetic/coil devices, velocity is always observed when electrical output is observed so magnetic/coil devices are velocity detectors. No. They may be either velocity or acceleration detectors. If the coil is attached to a ~freely suspended, but damped, mass, you get a velocity detector - eg a Lehman. If it is attached to a mass suspended on a spring, you get an acceleration detector. The length of the spring is constant if the velocity is constant. It only changes in length and causes the coil to move if there is an acceleration. A displacement sensor would record the relative distance from a some zero point at the instant of data read, the velocity sensor would record the relative velocity at the instant of data read, and acceleration sensor would detect the acceleration! eg a MEMs acclerometer. be a calculated number found by using the data from any two velocity data points and any three displacement data points. Agreed. Finally, if two seismometers, identical except for detectors, were placed side by side, they would both plot the identical earthquake wave form, assuming that the frequency characteristics were the same. No, they wouldn't. A velocity output is proportional to the differential (slope) of a position output plot with time. However, when it is recognized that displacement position is not time sensitive but velocity is, the builder can expect dramatic frequency response differences between displacement detectors and velocity detectors . Simply put, distance is distance, but velocity is the distance divided by the time needed to travel between two points. As a result, for velocity detectors, the longer the wave length, the less energy for each instant resulting in decreased voltage (and current) detected at each instant (for any defined magnetic field). Regards, Chris Chapman
In a message dated 23/11/2009, rsparks@.......... writes:
There=20 seems to be an ongoing difference of opinion of what constitutes a=20
velocity detector or an acceleration detector.  To my mind, if= a=20
seismometer automatically returns to a zero position, then it must= be=20
recording acceleration.  All vertical seismometers do this beca= use=20 they
all are measuring against gravity, so they would all be acceler= ation=20
devices.  Excepting the sensitivity to tilt, all horizontal=20 seismometers
also return to a zero position so they could also be ca= lled=20 acceleration
sensitive devices.  But maybe this description=20 oversimplifies the situation.
Hi Roger,
 
    Sorry, but no. You seem to be confusing= =20 devices which have AC and DC characteristics.
Some=20 sensors (capacitive and optical for example) clearly record
displace= ment=20 (neither acceleration or velocity). 
    Agreed.
On the=20 other hand, with magnetic/coil devices, velocity is always observed when= =20 electrical
output is observed so magnetic/coil devices are velocity= =20 detectors.
    No. They may be either velocity or accelerati= on=20 detectors. If the coil is attached to a ~freely suspended, but damped, mas= s, you=20 get a velocity detector - eg a Lehman. If it is attached to a mass suspend= ed on=20 a spring, you get an acceleration detector. The length of the spring is co= nstant=20 if the velocity is constant. It only changes in length and causes the coil= to=20 move if there is an acceleration.
A=20 displacement sensor would record the relative distance from a some zero= =20
point at the instant of data read, the velocity sensor would record= the=20
relative velocity at the instant of data read,  and acceleratio= n=20 sensor would
    detect the acceleration! eg a MEMs=20 acclerometer.
be a=20 calculated number found by using the data from any two velocity
data= =20 points and any three displacement data points.
    Agreed.
Finally,=20 if two seismometers, identical except for detectors, were
placed sid= e by=20 side, they would both plot the identical earthquake wave
form, assum= ing=20 that the frequency characteristics were the same. 
    No, they wouldn't. A velocity output is=20 proportional to the differential (slope) of a position output plot with=20 time.
 However, when it is recognized that displacement posi= tion is=20 not time
sensitive but velocity is, the builder can expect dramatic= =20 frequency
response differences between displacement detectors and ve= locity=20
detectors .  Simply put, distance is distance, but velocity is= the=20
distance divided by the time needed to travel between two=20 points.   As a
result, for velocity detectors, the longer= the=20 wave length, the less
energy for each instant resulting in decreased= =20 voltage (and current)
detected at each instant (for any defined magn= etic=20 field).
    Regards,
 
    Chris Chapman
 
Subject: Re: Integrating in WinQuake From: Barry Lotz barry_lotz@............. Date: Mon, 23 Nov 2009 19:58:26 -0800 (PST) All This seems to be a good one. I think we are having issues with semantics. Y= ou have the movement of the sensor and movement of the ground. One would li= ke the movement of the sensor ( which we can measure) to relate to movement= of the earth. One can only measure displacement (distortion of a material = - capacitive,LVDT, etc) or velocity(magnet/coil)=A0 of the sensor relative = to it's base (excluding GPS). Assuming the proper damping ,=A0 for short pe= riod sensors, the displacement of the sensor is linear with acceleration of= the earth. With long period sensors, the movement of the sensor relates to= the movement of the earth. If one is measuring displacement of the sensor = with say a Lehman, the output would be related to the displacement of the e= arth. The velocity of the sensor (magnet/coil) would relate to the velocity= of the earth. With feedback systems I'm not so sure. With STM's feedback h= e claimed that the displacement measured of the sensor related to the velocity of the earth. Regards Barry --- On Mon, 11/23/09, ChrisAtUpw@....... wrote: From: ChrisAtUpw@....... Subject: Re: Integrating in WinQuake To: psn-l@.............. Date: Monday, November 23, 2009, 6:09 PM =0A=0A =0A=0AIn a message dated 23/11/2009, rsparks@.......... writes:=0ATh= ere =0A seems to be an ongoing difference of opinion of what constitutes a= =0A =20 velocity detector or an acceleration detector.=A0 To my mind, if a =0A =20 seismometer automatically returns to a zero position, then it must be =0A = =20 recording acceleration.=A0 All vertical seismometers do this because =0A t= hey=20 all are measuring against gravity, so they would all be acceleration =0A = =20 devices.=A0 Excepting the sensitivity to tilt, all horizontal =0A seismome= ters=20 also return to a zero position so they could also be called =0A accelerati= on=20 sensitive devices.=A0 But maybe this description =0A oversimplifies the si= tuation.=0AHi Roger,=0A=A0=0A=A0=A0=A0=A0Sorry, but no. You seem to be=A0co= nfusing =0Adevices which have AC and DC characteristics.=0ASome =0A sensor= s (capacitive and optical for example) clearly record=20 displacement =0A (neither acceleration or velocity).=A0 =0A=A0=A0=A0=A0Agr= eed.=0AOn the =0A other hand, with magnetic/coil devices, velocity is alwa= ys observed when =0A electrical=20 output is observed so magnetic/coil devices are velocity =0A detectors.=0A= =A0=A0=A0=A0No. They may be either velocity or acceleration =0Adetectors. I= f the coil is attached to a ~freely suspended, but damped, mass, you =0Aget= a velocity detector - eg a Lehman. If it is attached to a mass suspended o= n =0Aa spring, you get an acceleration detector. The length of the spring i= s constant =0Aif the velocity is constant. It only changes in length and ca= uses the coil to =0Amove if there is an acceleration.=0AA =0A displacement= sensor would record the relative distance from a some zero =0A =20 point at the instant of data read, the velocity sensor would record the =0A= =20 relative velocity at the instant of data read,=A0 and acceleration =0A sen= sor would =0A=A0=A0=A0=A0detect the acceleration! eg a MEMs =0Aacclerometer= ..=0Abe a =0A calculated number found by using the data from any two veloci= ty=20 data =0A points and any three displacement data points.=0A=A0=A0=A0=A0Agre= ed.=0AFinally, =0A if two seismometers, identical except for detectors, we= re=20 placed side by =0A side, they would both plot the identical earthquake wav= e=20 form, assuming =0A that the frequency characteristics were the same.=A0=0A= =A0=A0=A0=A0No, they wouldn't. A velocity output is =0Aproportional to the = differential (slope) of a position output plot with =0Atime.=0A=A0However, = when it is recognized that displacement position is =0A not time=20 sensitive but velocity is, the builder can expect dramatic =0A frequency= =20 response differences between displacement detectors and velocity =0A =20 detectors .=A0 Simply put, distance is distance, but velocity is the =0A = =20 distance divided by the time needed to travel between two =0A points.=A0= =A0 As a=20 result, for velocity detectors, the longer the =0A wave length, the less= =20 energy for each instant resulting in decreased =0A voltage (and current)= =20 detected at each instant (for any defined magnetic =0A field).=0A=A0=A0=A0= =A0Regards,=0A=A0=0A=A0=A0=A0=A0Chris Chapman =0A=0A=A0
All
This seems to be a good one. I think w= e are having issues with semantics. You have the movement of the sensor and movement of the ground. One would like the move= ment of the sensor ( which we can measure) to relate to movement of the ear= th. One can only measure displacement (distortion of a material - capacitiv= e,LVDT, etc) or velocity(magnet/coil)  of the sensor relative to it's = base (excluding GPS). Assuming the proper damping ,  for short period = sensors, the displacement of the earth. With long period sensors, the movement of= the sensor relates to the movement of the earth. If one is measuring displ= acement of the sensor with say a Lehman, the output would be related to the displacem= ent of the earth. The velocity of the sensor (magnet/coil) would relate to = the velocity of the earth. With feedback systems I'm not so sure. With STM'= s feedback he claimed that the displacement measured of the sensor related to the velocity of the <= span style=3D"text-decoration: underline;">earth.
Regards
Barr= y


--- On Mon, 11/23/09, ChrisAtUpw@....... <ChrisAtUpw@= aol.com> wrote:

From: ChrisAtUpw= @....... <ChrisAtUpw@.......>
Subject: Re: Integrating in WinQuake=
To: psn-l@..............
Date: Monday, November 23, 2009, 6:09 PM
=0A=0A =0A=0A
In a message dated 23/11/2009, = rsparks@.......... writes:
=0A
There =0A = seems to be an ongoing difference of opinion of what constitutes a =0A velocity detector or an acceleration detector.  To my mind, if a =0A =
seismometer automatically returns to a zero position, then it must be = =0A
recording acceleration.  All vertical seismometers do this be= cause =0A they
all are measuring against gravity, so they would all be= acceleration =0A
devices.  Excepting the sensitivity to tilt, al= l horizontal =0A seismometers
also return to a zero position so they c= ould also be called =0A acceleration
sensitive devices.  But mayb= e this description =0A oversimplifies the situation.
= =0A
Hi Roger,
=0A
 
=0A
    = Sorry, but no. You seem to be confusing =0Adevices which have AC and D= C characteristics.
=0A
Some =0A sensors (= capacitive and optical for example) clearly record
displacement =0A (n= either acceleration or velocity). 
=0A
 &= nbsp;  Agreed.
=0A
On the =0A o= ther hand, with magnetic/coil devices, velocity is always observed when =0A= electrical
output is observed so magnetic/coil devices are velocity = =0A detectors.
=0A
    No. They= may be either velocity or acceleration =0Adetectors. If the coil is attach= ed to a ~freely suspended, but damped, mass, you =0Aget a velocity detector= - eg a Lehman. If it is attached to a mass suspended on =0Aa spring, you g= et an acceleration detector. The length of the spring is constant =0Aif the= velocity is constant. It only changes in length and causes the coil to =0A= move if there is an acceleration.
=0A
A = =0A displacement sensor would record the relative distance from a some zer= o =0A
point at the instant of data read, the velocity sensor would rec= ord the =0A
relative velocity at the instant of data read,  and a= cceleration =0A sensor would
=0A
   = ; detect the acceleration! eg a MEMs =0Aacclerometer.
=0Abe a =0A calculated number found by using the data fr= om any two velocity
data =0A points and any three displacement data po= ints.
=0A
    Agreed.
=0AFinally, =0A if two seismometers, identical ex= cept for detectors, were
placed side by =0A side, they would both plot= the identical earthquake wave
form, assuming =0A that the frequency c= haracteristics were the same. =0A
  =   No, they wouldn't. A velocity output is =0Aproportional to the = differential (slope) of a position output plot with =0Atime.
=0A However, when it is recognized that displaceme= nt position is =0A not time
sensitive but velocity is, the builder can= expect dramatic =0A frequency
response differences between displaceme= nt detectors and velocity =0A
detectors .  Simply put, distance i= s distance, but velocity is the =0A
distance divided by the time neede= d to travel between two =0A points.   As a
result, for veloc= ity detectors, the longer the =0A wave length, the less
energy for eac= h instant resulting in decreased =0A voltage (and current)
detected at= each instant (for any defined magnetic =0A field).=0A=
    Regards,
=0A
 
=0A
&nbs= p;   Chris Chapman
=0A
<= /div>=0A
 
Subject: Re: Integrating in WinQuake From: RSparks rsparks@.......... Date: Tue, 24 Nov 2009 23:04:04 -0800 Hello All, Brett makes a particularly good point when he comments that "You can not say that a ground motion is only a displacement, or a velocity, or an acceleration, it is always all three.". Geoffrey makes the same point when he offers the equations that relate the three metrics. I am not familiar with the MEMS accelerometers but Wikipedia has an informative article on Accelerometers . It is interesting to see that capacitive detection (which is displacement sensing) is a common way for these micro seismometers to sense acceleration. Other methods of detection (that I am not familiar with) are also used. Perhaps our experience with the automobile colors our thinking. With the car, first we accelerate, then we have velocity and finally, distance is traveled. A very time sequenced pattern. If we examine this same series of events on a micro scale, we can only find velocity (which may be zero) or change in velocity (acceleration). There is nothing else. Any non zero measurement will have a distance component and a time component (back to the three equations). Perhaps we should think of detection in terms of energy. If we have velocity, then the moving mass has kinetic energy. The magnet/coil system extracts energy from the velocity (and slows/opposes the relative motion) with the result that power is sent to the amplifier. On the other hand, a capacitive or optic system uses external power to sense position. Knowing all the above, now let us make two seismometers, one using a magnet/coil detector and one using a capacitive detector. Move both from position 1 to position 2. Both will record a positive peak and then a negative peak (or the reverse). Each peak will correspond to the maximum acceleration, the first peak to maximum initial acceleration and the second peak to maximum deceleration (measured as negative acceleration). Apparently we can use either displacement or velocity detection to measure acceleration. Roger __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Integrating in WinQuake CORRECTION From: RSparks rsparks@.......... Date: Wed, 25 Nov 2009 09:37:35 -0800 Hello All, Please withdraw my posting of Tue, 24 Nov 2009 23:04:04 -0800 (attached) which contains a grievous error. I incorrectly described the output of the displacement and velocity detectors as being identical but as Chris tried to tell me (following a previous reference to identity) (but I failed to understand), they are much different. My error came when I wrote " Knowing all the above, now let us make two seismometers, one using a magnet/coil detector and one using a capacitive detector. Move both from position 1 to position 2. Both will record a positive peak and then a negative peak (or the reverse). Each peak will correspond to the maximum acceleration, the first peak to maximum initial acceleration and the second peak to maximum deceleration (measured as negative acceleration). Apparently we can use either displacement or velocity detection to measure acceleration. " The output of the displacement detector is correctly described but the description of the output of the velocity sensor is grossly wrong. During the movement from position 1 to position 2, the seismometer must accelerate, reach a velocity, and then decelerate, stopping at position 2. Because the velocity detector is extracting energy from motion through a magnetic field, the velocity detector first measures the motion of the initial movement, then the motion caused by the return to a zero position forced by the return mechanism, then the motion caused by deceleration, and (finally) the motion of the final return to zero position caused by the return mechanism after the stop at position 2 occurs. For the velocity detector, the simple movement of the seismometer from position 2 to position 2 yields two positive peaks and two negative peaks. I write this before I have received any feedback. I expect that several commentators will describe the differences between the two detector outputs as they point out my error, and will do a much better job than I did. My apologies to all for the initial misdirection. Roger psn-l-digest-request@.............. wrote: > .------ ------ ------ ------ ------ ------ ------ ------ ------ ------. > | Message 1 | > '------ ------ ------ ------ ------ ------ ------ ------ ------ ------' > Subject: Re: Integrating in WinQuake > From: RSparks > Date: Tue, 24 Nov 2009 23:04:04 -0800 > > Hello All, > > Brett makes a particularly good point when he comments that "You can not > say that a ground motion is only a displacement, or a velocity, or an > acceleration, it is always all three.". Geoffrey makes the same point > when he offers the equations that relate the three metrics. > > I am not familiar with the MEMS accelerometers but Wikipedia has an > informative article on Accelerometers > . It is interesting to see > that capacitive detection (which is displacement sensing) is a common > way for these micro seismometers to sense acceleration. Other methods > of detection (that I am not familiar with) are also used. > > Perhaps our experience with the automobile colors our thinking. With > the car, first we accelerate, then we have velocity and finally, > distance is traveled. A very time sequenced pattern. > > If we examine this same series of events on a micro scale, we can only > find velocity (which may be zero) or change in velocity (acceleration). > There is nothing else. Any non zero measurement will have a distance > component and a time component (back to the three equations). > > Perhaps we should think of detection in terms of energy. If we have > velocity, then the moving mass has kinetic energy. The magnet/coil > system extracts energy from the velocity (and slows/opposes the relative > motion) with the result that power is sent to the amplifier. On the > other hand, a capacitive or optic system uses external power to sense > position. > > Knowing all the above, now let us make two seismometers, one using a > magnet/coil detector and one using a capacitive detector. Move both > from position 1 to position 2. Both will record a positive peak and > then a negative peak (or the reverse). Each peak will correspond to the > maximum acceleration, the first peak to maximum initial acceleration and > the second peak to maximum deceleration (measured as negative > acceleration). > > Apparently we can use either displacement or velocity detection to > measure acceleration. > > Roger > > > > > > > > > > > > > > > > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-DIGEST-REQUEST@.............. with > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. > > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Integrating in WinQuake CORRECTION From: "Geoffrey" gmvoeth@........... Date: Wed, 25 Nov 2009 16:55:29 -0700 Hello, Dont mean to butt in but It all seems too complex, Velocity types are magnet coil arrangements. the voltage relates to the strength and velocity of the magnet/coil pair. Maximum velocity/voltage happens as the movement crosses zero point. Minimum velocity/voltage ( closest to zero ) happens at peak displacement(+/-) I think velocity and voltage are a linear type equation. When it comes to displacement only, Maximum will be max or min capacitance which happens along with the motion. I think capacitance is related to the square of the distance between the plates. Thus is the voltage produced too. While in motion These two types of sensors are producing signals seperated , it seems to me , by 90 degrees at exactly the same moment in time. One must be sin and the other cosin (your choice here) related to actual motion ?? It does make a difference which type of sensor you have. But if you filter anything with hardware most likely you can never be acactly sure what the picture is showing without being able to compensate exactly with some kind of software working over the data. It seems moot to me that amateures are worrying about things that cost big bucks to remedy and this kind of thought belongs in the realm of the pros like USGS or the OIL companies. I look at this with only the high school part of my math education. I remember this better than college. ??? Any thoughts, geoff ----- Original Message ----- From: "RSparks" To: Sent: Wednesday, November 25, 2009 10:37 AM Subject: Re: Integrating in WinQuake CORRECTION > Hello All, > > Please withdraw my posting of Tue, 24 Nov 2009 23:04:04 -0800 (attached) > which contains a grievous error. I incorrectly described the output of > the displacement and velocity detectors as being identical but as Chris > tried to tell me (following a previous reference to identity) (but I > failed to understand), they are much different. > > My error came when I wrote " > > Knowing all the above, now let us make two seismometers, one using a > magnet/coil detector and one using a capacitive detector. Move both > from position 1 to position 2. Both will record a positive peak and > then a negative peak (or the reverse). Each peak will correspond to the > maximum acceleration, the first peak to maximum initial acceleration and > the second peak to maximum deceleration (measured as negative > acceleration). > > Apparently we can use either displacement or velocity detection to > measure acceleration. > > " > The output of the displacement detector is correctly described but the > description of the output of the velocity sensor is grossly wrong. > During the movement from position 1 to position 2, the seismometer must > accelerate, reach a velocity, and then decelerate, stopping at position > 2. Because the velocity detector is extracting energy from motion > through a magnetic field, the velocity detector first measures the > motion of the initial movement, then the motion caused by the return to > a zero position forced by the return mechanism, then the motion caused > by deceleration, and (finally) the motion of the final return to zero > position caused by the return mechanism after the stop at position 2 > occurs. For the velocity detector, the simple movement of the > seismometer from position 2 to position 2 yields two positive peaks and > two negative peaks. > > I write this before I have received any feedback. I expect that several > commentators will describe the differences between the two detector > outputs as they point out my error, and will do a much better job than I > did. My apologies to all for the initial misdirection. > > Roger > > > psn-l-digest-request@.............. wrote: >> .------ ------ ------ ------ ------ ------ ------ ------ ------ ------. >> | Message 1 | >> '------ ------ ------ ------ ------ ------ ------ ------ ------ ------' >> Subject: Re: Integrating in WinQuake >> From: RSparks >> Date: Tue, 24 Nov 2009 23:04:04 -0800 >> >> Hello All, >> >> Brett makes a particularly good point when he comments that "You can not >> say that a ground motion is only a displacement, or a velocity, or an >> acceleration, it is always all three.". Geoffrey makes the same point >> when he offers the equations that relate the three metrics. >> >> I am not familiar with the MEMS accelerometers but Wikipedia has an >> informative article on Accelerometers >> . It is interesting to see >> that capacitive detection (which is displacement sensing) is a common >> way for these micro seismometers to sense acceleration. Other methods >> of detection (that I am not familiar with) are also used. >> >> Perhaps our experience with the automobile colors our thinking. With >> the car, first we accelerate, then we have velocity and finally, >> distance is traveled. A very time sequenced pattern. >> >> If we examine this same series of events on a micro scale, we can only >> find velocity (which may be zero) or change in velocity (acceleration). >> There is nothing else. Any non zero measurement will have a distance >> component and a time component (back to the three equations). >> >> Perhaps we should think of detection in terms of energy. If we have >> velocity, then the moving mass has kinetic energy. The magnet/coil >> system extracts energy from the velocity (and slows/opposes the relative >> motion) with the result that power is sent to the amplifier. On the >> other hand, a capacitive or optic system uses external power to sense >> position. >> >> Knowing all the above, now let us make two seismometers, one using a >> magnet/coil detector and one using a capacitive detector. Move both >> from position 1 to position 2. Both will record a positive peak and >> then a negative peak (or the reverse). Each peak will correspond to the >> maximum acceleration, the first peak to maximum initial acceleration and >> the second peak to maximum deceleration (measured as negative >> acceleration). >> >> Apparently we can use either displacement or velocity detection to >> measure acceleration. >> >> Roger >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> __________________________________________________________ >> >> Public Seismic Network Mailing List (PSN-L) >> >> To leave this list email PSN-L-DIGEST-REQUEST@.............. with >> the body of the message (first line only): unsubscribe >> See http://www.seismicnet.com/maillist.html for more information. >> >> > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Earthquake prediction book From: "Dale Hardy" photon1@........... Date: Sat, 5 Dec 2009 13:02:52 +1100 ----- Original Message -----=20 From: Kirsten Chojnicki=20 To: VOLCANO@.......... Sent: Saturday, December 05, 2009 6:01 AM Subject: VOLCANO: new book of possible interest *************************************************************************= *** new book of possible interest From: "Susan Hough" *************************************************************************= *** Hi, My new book on earthquake prediction was just published, and might be of interest to listserv members who wonder why earthquakes, unlike = volcanoes, remain so vexingly unpredictable. The official publication date is = 1/2010 but in fact books are available now -- they can be ordered on-line and Princeton will have copies at AGU. Cheers, Susan Susan Hough hough@............... -------------------------- An earthquake can strike without warning and wreak horrific destruction and death, whether it's the cataclysmic 2008 Sichuan quake in China or a future great earthquake on the San Andreas Fault in California, which scientists know is inevitable. Yet despite rapid advances in earthquake science, seismologists still can't predict when the Big One will hit. Predicting the Unpredictable is the first book to explain why, exploring the fact and fiction behind the science--and pseudoscience--of = earthquake prediction. Predicting the Unpredictable: The Tumultuous Science of Earthquake Prediction, S. Hough (January 2010) 262 pp. ISBN: 978-0-691-13816-9. US$24.95,=A316.95. URL: http://press.princeton.edu/titles/8990.html
 
----- Original Message -----=20
From: Kirsten = Chojnicki=20
Sent: Saturday, December 05, 2009 6:01 AM
Subject: VOLCANO: new book of possible interest


******************************************************= **********************
new=20 book of possible interest
From: "Susan Hough" <hough@...............>
**= *************************************************************************= *

Hi,
My=20 new book on earthquake prediction was just published, and might be=20 of
interest to listserv members who wonder why earthquakes, unlike=20 volcanoes,
remain so vexingly unpredictable.  The official = publication=20 date is 1/2010
but in fact books are available now -- they can be = ordered=20 on-line and
Princeton will have copies at=20 AGU.
Cheers,
Susan


Susan Hough
hough@...............

--------------------------

An=20 earthquake can strike without warning and wreak horrific = destruction
and=20 death, whether it's the cataclysmic 2008 Sichuan quake in China or = a
future=20 great earthquake on the San Andreas Fault in California, = which
scientists=20 know is inevitable. Yet despite rapid advances in earthquake
science, = seismologists still can't predict when the Big One will = hit.
Predicting the=20 Unpredictable is the first book to explain why, exploring
the fact = and=20 fiction behind the science--and pseudoscience--of=20 earthquake
prediction.

Predicting the Unpredictable: The = Tumultuous=20 Science of Earthquake
Prediction, S. Hough (January 2010) 262 pp. = ISBN:=20 978-0-691-13816-9.
US$24.95,=A316.95.  URL: http://press.princeton.edu/titles/8990.html

 

Subject: Re: Real time traces From: Barry Lotz barry_lotz@............. Date: Sat, 5 Dec 2009 11:29:50 -0800 (PST) Hi Dave I sent a note to Brett but maybe you are the one to ask. Now that my sensor= s are behaving I would like to experiment with a sensor similar to yours. W= here did you buy your spring stock? I checked the internet and only found l= arger quantities. Is there a way to calculate the sensor geometric control = points? ie spring attachments, center of mass & center of hinge? Regards =0ABarry =0Ahttp://www.seismicvault.com --- On Sat, 8/15/09, Dave Nelson wrote: From: Dave Nelson Subject: Re: Real time traces To: psn-l@.............. Date: Saturday, August 15, 2009, 6:43 PM =0A=0A =0A =0A=0AHi Meredith.=0A=A0=0AThe spring is cut to width on my pers= onal shear and =0Aheat treated in the home oven in the automatic cleaning m= ode.=A0 The heat =0Atreat significantly increases the yield strength. The t= emperature is just right =0Aas measured with a thermocouple. The width for = the instrument pictured is 16 mm =0Aand thickness is 12 mils.=A0 (Sorry for= the mixed units -- our European =0Afriends will think we can't=A0 make up = our minds )=A0=0A=A0=0A=A0I have a large quantity of the raw material =0Afo= r the springs -- enough for any conceivable quantity of instruments. I am = =0Aworking on the =A0repeatability in the shearing process. Right now I can= do =0A+- ~.15mm.=0A=A0=0AAs you suggest the period is=A0 a function of =0A= the spring length and adjusted at the clamp. It sometimes takes a few tries= but =0Athe process is quite easy.=A0 The period and rough centering are do= ne with =0Athe=A0 center capacitor plate PC board =A0removed to allow for a= motion =0Aover large angle for convenience. The final mass centering is do= ne by adjusting =0Athe moveable mass =A0either by eye or using the LED's on= the electronics =0Aboard with the loop open. The integrator is designed to= hold center over a wide =0Atemperature range so reentering is probably not= necessary under all but the most =0Asevere climatic temperature changes. W= e estimate +- 30C=A0 but that is not =0Afully confirmed.=0A=A0=0A=A0=0AActu= ator is homebrew based in a Neodymium magnet =0Apurchased on Ebay. The coil= is wound on a modified PAC plumbing part=A0 (1 =0A1/4 Schedule 40 plug fro= m Lowes).=A0=A0It takes a few minutes of lathe =0Awork to make it=A0. The c= oil is 770 turns=A0of # 32 for about 50 ohms and =0A15 N/A. I fabricate the= magnet assembly also but it does take some minor=A0 =0AMIG tack welds. The= materials are available=A0=A0from Online Metals. =0A=0A=A0=0AThere is anot= her small mass at he coil attach point =0Aof=A0~ 10 grams.=A0 =0A=A0=0AThe = overall size of the basic mechanism exclusive =0Aof the case is 4.5 x 9.5 i= nches. I have a new (untried) design which will be 4.5 =0Ax 5 inches in a = somewhat different configuration which may=A0allow for=A0 =0Abuoyancy compe= nsation. =A0The new design is also easier to build or at least =0Athat is t= he goal. =0A=A0=0A=A0=0ARegards, Dave =0A=A0=0A=A0=0A=A0=0A=A0=0A----- Orig= inal Message ----- =0A=0A From: =0A meredith lamb =0A To: psn-l@webtroni= cs.com =0A Sent: Sunday, August 16, 2009 00:18=0A Subject: Re: Real time = traces=0A =20 =0A Hi Dave,=0A =A0=0A Thanks for the info.=A0 Was wondering about the m= ain spring =0A width...its hard to judge from the photo; and where you got= such=0A and the ~ cost?=A0 The photo spring looks to be a original coil s= trip =0A or a good home shear.=A0 I understand (via the web) its=0A magne= tic; but apparently it works fine regardless of the boom end =0A coil/magn= et actuator feedback influence.=A0=0A =A0=0A Midway atop your vertical me= chanism there appears to be a screw =0A adjustable mass balance or centeri= ng=A0counterweight.=0A =A0=0A I presume....that the main spring period is= adjusted via the back clamp =0A alone.=A0 =0A =A0=0A The very small siz= e=A0of the vertical is rather=A0startling for the =0A ~ giant ~ mechanisms= we're used too seeing on PSN.=0A I can't really tell if their is more add= ed mass to the boom via =0A the=A0photo's besides the ~ frame, coil,=A0cap= acitance plate.=0A =A0=0A What did you use for the coil?=A0 Homebrew woun= d or otherwise a =0A commerical coil?=0A =A0=0A What is the magnet, ring= ceramic or neodymium?=0A =A0=0A Take care, Meredith Lamb=0A =A0=0A =A0= =0A On Fri, Aug 14, 2009 at 12:12 PM, Dave Nelson wr= ote: =0A =0A =0A Hi Meredith,=0A =A0=0A The spring is 17-7=A0 stain= less condition C =0A heat treated to condition CH900. Thickness is 12 mi= ls. =A0The pivots are =0A 2 mil stainless single axis=A0.=A0 Pivot lengt= h is only about 12 mils. =0A They are held=A0 tension by the=A0C spring.= A two axis pivot is not =0A necessary.=0A =A0=0A =A0=0A Dave = =0A =A0=0A =A0=0A =0A =A0
Hi Dave
I sent a note to Brett but maybe y= ou are the one to ask. Now that my sensors are behaving I would like to exp= eriment with a sensor similar to yours. Where did you buy your spring stock= ? I checked the internet and only found larger quantities. Is there a way t= o calculate the sensor geometric control points? ie spring attachments, cen= ter of mass & center of hinge?


Regards
=0ABarry
=0Ahtt= p://www.seismicvault.com


--- On Sat, 8/15/09, Dave Nelson = <davefnelson@.......> wrote:

= From: Dave Nelson <davefnelson@.......>
Subject: Re: Real time tra= ces
To: psn-l@..............
Date: Saturday, August 15, 2009, 6:43 PM=

=0A=0A =0A =0A=0A
Hi Meredith.
=0A
 
=0A
The spring is cut to width on my personal shear and =0Aheat treated in the= home oven in the automatic cleaning mode.  The heat =0Atreat signific= antly increases the yield strength. The temperature is just right =0Aas mea= sured with a thermocouple. The width for the instrument pictured is 16 mm = =0Aand thickness is 12 mils.  (Sorry for the mixed units -- our Europe= an =0Afriends will think we can't  make up our minds ) =0A
 
=0A
 I have a large quantity of the raw materia= l =0Afor the springs -- enough for any conceivable quantity of instruments.= I am =0Aworking on the  repeatability in the shearing process. Right = now I can do =0A+- ~.15mm.
=0A
 
=0A
As you sugge= st the period is  a function of =0Athe spring length and adjusted at t= he clamp. It sometimes takes a few tries but =0Athe process is quite easy.&= nbsp; The period and rough centering are done with =0Athe  center capa= citor plate PC board  removed to allow for a motion =0Aover large angl= e for convenience. The final mass centering is done by adjusting =0Athe mov= eable mass  either by eye or using the LED's on the electronics =0Aboa= rd with the loop open. The integrator is designed to hold center over a wid= e =0Atemperature range so reentering is probably not necessary under all bu= t the most =0Asevere climatic temperature changes. We estimate +- 30C = but that is not =0Afully confirmed.
=0A
 
=0A
 
=0A
Actuator is homebr= ew based in a Neodymium magnet =0Apurchased on Ebay. The coil is wound on a= modified PAC plumbing part  (1 =0A1/4 Schedule 40 plug from Lowes).&n= bsp; It takes a few minutes of lathe =0Awork to make it . The coi= l is 770 turns of # 32 for about 50 ohms and =0A15 N/A. I fabricate th= e magnet assembly also but it does take some minor  =0AMIG tack welds.= The materials are available  from Online Metals. =0A=0A
 
=0A
There is another small mass at he coil attach poin= t =0Aof ~ 10 grams. 
=0A
 
=0A
The o= verall size of the basic mechanism exclusive =0Aof the case is 4.5 x 9.5 in= ches. I have a new (untried) design which will be 4.5 =0Ax 5 inches in a s= omewhat different configuration which may allow for  =0Abuoyancy = compensation.  The new design is also easier to build or at least =0At= hat is the goal.
=0A
 
=0A
 
= =0A
Regards, Dave
=0A
=  
=0A
 
=0A
=  
=0A
 =0A
----- Original Message -----
=0A
=0A
From: =0A <= a rel=3D"nofollow" title=3D"paleoartifact@........." ymailto=3D"mailto:pale= oartifact@........." target=3D"_blank" href=3D"/mc/compose?to=3Dpaleoartifa= ct@.........">meredith lamb
=0A =0A =
Sent: Sunday, = August 16, 2009 00:18
=0A
Subject: Re: Real time traces
=0A

= =0A
Hi Dave,
=0A
 
=0A
Thanks for the info= ..  Was wondering about the main spring =0A width...its hard to judge = from the photo; and where you got such
=0A
and the ~ cost? = The photo spring looks to be a original coil strip =0A or a good home she= ar.  I understand (via the web) its
=0A
magnetic; but appar= ently it works fine regardless of the boom end =0A coil/magnet actuator fe= edback influence. 
=0A
 
=0A
Midway atop yo= ur vertical mechanism there appears to be a screw =0A adjustable mass bala= nce or centering counterweight.
=0A
 
=0A
I= presume....that the main spring period is adjusted via the back clamp =0A = alone. 
=0A
 
=0A
The very small size&nbs= p;of the vertical is rather startling for the =0A ~ giant ~ mechanism= s we're used too seeing on PSN.
=0A
I can't really tell if their= is more added mass to the boom via =0A the photo's besides the ~ fra= me, coil, capacitance plate.
=0A
 
=0A
What= did you use for the coil?  Homebrew wound or otherwise a =0A commeri= cal coil?
=0A
 
=0A
What is the magnet, ring cer= amic or neodymium?
=0A
 
=0A
Take care, Meredith= Lamb
=0A
 
=0A
 
=0A
On Fri, Aug 14, 2009 at 12:12 PM, Dave Nelson <davefnelson@.......> wrote:
=0A
=0A
=0A
Hi Mered= ith,
=0A
 <= /div>=0A
The spring is 17-7  s= tainless condition C =0A heat treated to condition CH900. Thickness is 1= 2 mils.  The pivots are =0A 2 mil stainless single axis . = ; Pivot length is only about 12 mils. =0A They are held  tension by= the C spring. A two axis pivot is not =0A necessary.
= =0A
 
=0A
 =0A
Dave
=0A
=  
=0A
 
=0A
=0A
 
Subject: Adjusting a Lehman From: "Ted Channel" tchannel@............ Date: Sun, 6 Dec 2009 06:02:19 -0700 Hi Folks, This is the basic process I use to adj. a Lehman. 1. I assembly everything and level everything. Once this is = completed the vertical part of the frame is plumb. The boom, and frame = are parallel with the earth and the boom is resting on the centerline. 2. I time the period and start raising the front adjusting leg, = tweaking the side adj. legs as necessary to maintain the boom on the = center line. When I get a stable 20 second period I am finished. These are my questions: When I perform this set up, the vertical = frame member is now tilting backward, and the mass end of the boom has = be raised. Now the boom is no longer parallel to the earth. 1. "What would happen" if I extended the wire support, lowering the = boom back to parallel to the earth, but not changing the vertical = member. To my knowledge I have never done this, I just leave the boom = with mass end raised via the front adj. leg. 2. Should I make this adjustment, returning the boom to parallel, by = lengthen the support wire? I have tried it, but the adjustments are so small I can't measure the = results. Thanks, Ted
Hi Folks,   This is the basic = process I=20 use to adj. a Lehman.
1.  I assembly everything and = level=20 everything.    Once this is completed the vertical part = of the=20 frame is plumb.   The boom, and frame are parallel = with the=20 earth and the boom is resting on the centerline.
2.  I time the period and start = raising the=20 front adjusting leg, tweaking the side adj. legs as necessary to = maintain the=20 boom on the center line.  When I get a stable 20 second period I am = finished.
 
These are my = questions:    When=20 I perform this set up, the vertical frame member is now tilting = backward, and=20 the mass end of the boom has be raised.  Now the boom is no = longer=20 parallel to the earth.
 
1.  "What would happen" if I = extended the wire=20 support, lowering the boom back to parallel to the earth, but not = changing the=20 vertical member.   To my knowledge I have never done this, I = just=20 leave the boom with mass end raised via the front adj. leg.
 
2.  Should I make this adjustment, = returning=20 the boom to parallel, by lengthen the support wire?
 
I have tried it, but the adjustments = are so small I=20 can't measure the results.
 
Thanks, Ted
Subject: Win SDR Problem From: "GPayton" gpayton@............. Date: Sun, 6 Dec 2009 07:53:49 -0600 I am asking the group about a GPS problem that I am experiencing with WinSDR, Larry's A/D box and the Garmin 18x receiver connected. Larry and I have not found a fix yet, and I was wondering if anyone else had a similar problem. As you may know Garmin replaced their GPS-18 with the 18x model. I "think" the only difference is it is more sensitive. Nevertheless, my connection receives the timing signals, makes the necessary adjustments and "locks" the software as designed. That is well and good. However, it does not receive the PGRMT message allowing it to fix my position into the software and display same in the GPS Location window. I contacted Garmin Technical Center and their reply was, "I have looked through the technical specifications and all of our Garmin proprietary sentences and do not see nor recognize the PGRMT sentence." Surely, I am not the only person that has received a 18x model receiver! I do not know IF the model 18 did receive that message and the 18x does not or what is going on? I've plugged in my coordinates obtained from my handheld GPS elsewhere in the program and that should suffice. But, I would like for everything to work as advertized. Anyone else using the 18x and had this problem? And, most of all, the FIX. Thanks, Jerry
 
I am asking the group about a GPS problem that I am experiencing = with=20 WinSDR, Larry's A/D box and the Garmin 18x receiver connected.  = Larry and I=20 have not found a fix yet, and I was wondering if anyone else had a = similar=20 problem.
 
As you may know Garmin replaced their GPS-18 with the 18x = model.  I=20 "think" the only difference is it is more sensitive.  Nevertheless, = my=20 connection receives the timing signals, makes the necessary adjustments = and=20 "locks" the software as designed.  That is well and good.
 
However, it does not receive the PGRMT message allowing it to fix = my=20 position into the software and display same in the GPS Location = window.
 
I contacted Garmin Technical Center and their reply was, "I have = looked=20 through the technical specifications and all of our Garmin proprietary = sentences=20 and do not see nor recognize the PGRMT sentence." 
 
Surely, I am not the only person that has received a 18x model=20 receiver!  I do not know IF the model 18 did receive that message = and the=20 18x does not or what is going on?  I've plugged in my coordinates = obtained=20 from my handheld GPS elsewhere in the program and that should = suffice. =20 But, I would like for everything to work as advertized.
 
Anyone else using the 18x and had this problem? And, most = of all,=20 the FIX.
 
Thanks,
Jerry
 
 
Subject: Re: Adjusting a Lehman From: Barry Lotz barry_lotz@............. Date: Sun, 6 Dec 2009 07:24:59 -0800 (PST) Hi Ted To me the important thing is that the upper hinge is slightly forward of th= e lower hinge. If not the beam would go to one side or the other and stay. = Since you have a period (oscillation), the orientation should be ok. The bo= om orientation with the earth shouldn't matter. Regards =0ABarry =0Ahttp://www.seismicvault.com --- On Sun, 12/6/09, Ted Channel wrote: From: Ted Channel Subject: Adjusting a Lehman To: "psn" Date: Sunday, December 6, 2009, 5:02 AM =0A=0A =0A =0A=0AHi Folks,=A0=A0 This is the basic process I =0Ause to adj.= a Lehman.=0A1.=A0 I assembly everything and level =0Aeverything.=A0=A0=A0 = Once this is completed the vertical part of the =0Aframe is plumb.=A0=A0=A0= The boom, and frame=A0are parallel with the =0Aearth and the boom is restin= g on the centerline.=0A2.=A0 I time the period and start raising the =0Afro= nt adjusting leg, tweaking the side adj. legs as necessary to maintain the = =0Aboom on the center line.=A0 When I get a stable 20 second period I am = =0Afinished.=0A=A0=0AThese are=A0my questions:=A0=A0=A0 When =0AI perform t= his set up, the vertical frame member is now tilting backward, and =0Athe= =A0mass end of the boom has be raised.=A0 Now the boom is no longer =0Apara= llel to the earth.=0A=A0=0A1.=A0 "What would happen" if I extended the wire= =0Asupport, lowering the boom back to parallel to the earth, but not chang= ing the =0Avertical member.=A0=A0 To my knowledge I have never done this, I= just =0Aleave the boom with mass end raised via the front adj. leg.=0A=A0= =0A2.=A0 Should I make this adjustment, returning =0Athe boom to parallel, = by lengthen the support wire?=0A=A0=0AI have tried it, but the adjustments = are so small I =0Acan't measure the results.=0A=A0=0AThanks, Ted
Hi Ted
To me the important thing is that t= he upper hinge is slightly forward of the lower hinge. If not the beam woul= d go to one side or the other and stay. Since you have a period (oscillatio= n), the orientation should be ok. The boom orientation with the earth shoul= dn't matter.

Regards
=0ABarry
=0Ahttp://www.seismicvault.com
--- On Sun, 12/6/09, Ted Channel <tchannel@............><= /i> wrote:

From: Ted Channel <tchann= el@............>
Subject: Adjusting a Lehman
To: "psn" <psn-l@w= ebtronics.com>
Date: Sunday, December 6, 2009, 5:02 AM

=0A=0A =0A =0A=0A
Hi Folks,   This is the basic process I =0Ause to ad= j. a Lehman.
=0A
1.  I= assembly everything and level =0Aeverything.    Once this i= s completed the vertical part of the =0Aframe is plumb.   Th= e boom, and frame are parallel with the =0Aearth and the boom is resti= ng on the centerline.
=0A
2= ..  I time the period and start raising the =0Afront adjusting leg, twe= aking the side adj. legs as necessary to maintain the =0Aboom on the center= line.  When I get a stable 20 second period I am =0Afinished.<= /div>=0A
 
=0A
These are my questions:   = When =0AI perform this set up, the vertical frame member is now tilting ba= ckward, and =0Athe mass end of the boom has be raised.  Now the b= oom is no longer =0Aparallel to the earth.
=0A
 
=0A
1.  "What would happen" if I extended the wire =0Asupport, lower= ing the boom back to parallel to the earth, but not changing the =0Avertica= l member.   To my knowledge I have never done this, I just =0Alea= ve the boom with mass end raised via the front adj. leg.
=0A 
=0A
2.  Should I make this adjustment, returning =0Athe = boom to parallel, by lengthen the support wire?
=0A
 
=0A
I have tried it, but the adjustments are so small I =0Acan't mea= sure the results.
=0A
 
=0A
Thanks, Ted
Subject: Re: Adjusting a Lehman From: ChrisAtUpw@....... Date: Sun, 6 Dec 2009 12:27:41 EST In a message dated 06/12/2009, tchannel@............ writes: Hi Folks, This is the basic process I use to adj. a Lehman. 1. I assembly everything and level everything. Once this is completed the vertical part of the frame is plumb. The boom, and frame are parallel with the earth and the boom is resting on the centreline. 2. I time the period and start raising the front adjusting leg, tweaking the side adj. legs as necessary to maintain the boom on the centre line. When I get a stable 20 second period I am finished. These are my questions: When I perform this set up, the vertical frame member is now tilting backward, and the mass end of the boom has be raised. Now the boom is no longer parallel to the earth. 1. "What would happen" if I extended the wire support, lowering the boom back to parallel to the earth, but not changing the vertical member. To my knowledge I have never done this, I just leave the boom with mass end raised via the front adj. leg. 2. Should I make this adjustment, returning the boom to parallel, by lengthen the support wire? I have tried it, but the adjustments are so small I can't measure the results. Hi Ted, The period is determined by 1) the angle 'A' between the vertical and the true swing axis and by 2) the radius of gyration 'k' of the pendulum. k depends on the weight and shape of the mass and of the arm. It is usual to use a rigid light tubular arm. Lifting or lowering the arm a bit will provide a Cosine Theta correction to k, so you could see a few parts per thousand change. Usual values of the swing angle are about 1/3 degree for a 20 second period and a 24" arm. T = 2xPixSqrt(k / gxsin(A)) Avoid very short arms, say 12". The value of A becomes very small and the pendulum will experience tilt drift due to very small ground movements as the seasons, rainfall and temperatures change. You need to design your sensor system so that it's output is independent of any tilt drift. The layout of the sensor and the magnetic damping with the frame should be your primary concern. Regards, Chris Chapman
In a message dated 06/12/2009, tchannel@............ writes:
Hi Folks,   This is the basic= process I=20 use to adj. a Lehman.
1.  I assembly everything and leve= l=20 everything.    Once this is completed the vertical part= of the=20 frame is plumb.   The boom, and frame are parallel= with=20 the earth and the boom is resting on the centreline.
2.  I time the period and start ra= ising the=20 front adjusting leg, tweaking the side adj. legs as necessary to maintai= n the=20 boom on the centre line.  When I get a stable 20 second period I am= =20 finished.
 
These are my questions:  = ; =20 When I perform this set up, the vertical frame member is now tilting bac= kward,=20 and the mass end of the boom has be raised.  Now the boom is= no=20 longer parallel to the earth.
1.  "What would happen" if I exten= ded the=20 wire support, lowering the boom back to parallel to the earth, but not= =20 changing the vertical member.   To my knowledge I have never= done=20 this, I just leave the boom with mass end raised via the front adj.=20 leg.
2.  Should I make this adjustment,= returning=20 the boom to parallel, by lengthen the support wire?
I have tried it, but the adjustments ar= e so small=20 I can't measure the results.
Hi Ted,
 
    The period is determined by 1) the angle 'A'= =20 between the vertical and the true swing axis and by 2) the radius of= =20 gyration 'k' of the pendulum. k depends on the weight and shape of the mas= s and=20 of the arm. It is usual to use a rigid light tubular arm. Lifting or= =20 lowering the arm a bit will provide a Cosine Theta correction to k, so=20 you could see a few parts per thousand change. 
 
    Usual values of the swing angle are about 1/3= =20 degree for a 20 second period and a 24" arm. T =3D 2xPixSqrt(k / gxsin(A))= Avoid=20 very short arms, say 12". The value of A becomes very small and the pendul= um=20 will experience tilt drift due to very small ground movements as the seaso= ns,=20 rainfall and temperatures change. You need to design your sensor syst= em so=20 that it's output is independent of any tilt drift.
    The layout of the sensor and the magnetic dam= ping=20 with the frame should be your primary concern.
 
    Regards,
 
    Chris Chapman
Subject: Posting of events by email to events@ (unable to do so) From: "Geoffrey" gmvoeth@........... Date: Sun, 6 Dec 2009 19:56:38 -0700 Hello Psn; I was playing with security of the NTFS format on my disk and after trying to REMOVE all security to make NTFS like FAT 32 was totally unable to reboot my machine TO WINDOWS no matter what. I could only access the Win Vista recovery console via the install disc yet was unable to use any tools to fix the NTFS security descriptors ( like ADMINISTRATORS = FULL ACCESS or EVERYONE = FULL ACCESS or whatever is the owner of everything) In the security properties. A couple of notes to you all from what I have learned. 1. Right after you REINSTALL windows to whatever partition the OS resides you will once again be able to reset everything. EVEN ON THOSE OTHER DISKS YOU TRIED TO REMOVE THAT BLASTED SECURITY FROM. Do not reformat everything only the partition holding the reinstallation. OR, You WILL loose everything that was in the original DISK. 2. AFTER you reinstall or originally install windows vista 64 you can then add or change to increase permissions for ALL partitions and at this time make ADMINISTRATORS instead of TRUSTED INSTALLER the owner of everything on ALL the disks. Now you can install anything and do everything you wanted to do by removing NTFS security in the first place. 3. There is no way I know you can totally remove security to make WIN VISTA 64 NTFS appear as free as a FAT32 formatted disk. WIN vista seems to have a new kind of (version) NTFS that only VISTA can deal with. You can make ALL partitions be primary ones. NEVER try to use Partition magic or other third party soft wares to modify a win vista partition. SPOTMAU 2008 was no good either for fixing this security thing. 4. Now to get to psn: Since reinstalling everything I can no longer post events to PSN event@ site, I get no responses like it is totally ignoring everything. No errors, my files simply disappear into that place in a IOWA corn field where the sun never shines. 5. I was lucky to have NORTON GHOST make a backup prior to this problem so not everything was lost only stuff after January of this year. Anyone have a solution to item number 4 ? Must I make all new accounts with PSN since restoring my system ? Sincerely, Geoff at GVA :-( __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: RE: Adjusting a Lehman From: "Stephen Hammond" shammon1@............. Date: Sun, 6 Dec 2009 22:58:13 -0800 Hi Chris, you got my attention when you talked about the length of the = arm and mass. Let=92s say A=92 is the pipe end of the arm, B=92 is the = location of the mass (say 5 lbs) and =93C=94 is the location of the brass damping = plate ( =BC lbs) on the original Lehman style design. Using your calculation below, would you measure the 24=94 arm from A=92 to B=92 or A=92 to C=92 ? = Take a look at http://pw2.netcom.com/~shammon1/compressed/e-w_Lehman.jpg and you will = see why I am asking. When I was in San Jose I had two Lehman=92s with 36=92 = arms and the worked great and they had 20-25 second periods without any effort. = When I moved to Aptos I had to reduce the length to 20=94 due to space issues = and they have never performed as well as I predicted. Now I=92m wondering if = I am measuring their arm length correctly. Comments? Steve Hammond PSN Aptos, CA =20 From: psn-l-request@.............. [mailto:psn-l-request@............... = On Behalf Of ChrisAtUpw@....... Sent: Sunday, December 06, 2009 9:28 AM To: psn-l@.............. Subject: Re: Adjusting a Lehman =20 In a message dated 06/12/2009, tchannel@............ writes: Hi Folks, This is the basic process I use to adj. a Lehman. 1. I assembly everything and level everything. Once this is = completed the vertical part of the frame is plumb. The boom, and frame are = parallel with the earth and the boom is resting on the centreline. 2. I time the period and start raising the front adjusting leg, = tweaking the side adj. legs as necessary to maintain the boom on the centre line. When I get a stable 20 second period I am finished. =20 These are my questions: When I perform this set up, the vertical = frame member is now tilting backward, and the mass end of the boom has be = raised. Now the boom is no longer parallel to the earth. 1. "What would happen" if I extended the wire support, lowering the = boom back to parallel to the earth, but not changing the vertical member. = To my knowledge I have never done this, I just leave the boom with mass end = raised via the front adj. leg. 2. Should I make this adjustment, returning the boom to parallel, by lengthen the support wire? I have tried it, but the adjustments are so small I can't measure the results. Hi Ted, =20 The period is determined by 1) the angle 'A' between the vertical = and the true swing axis and by 2) the radius of gyration 'k' of the = pendulum. k depends on the weight and shape of the mass and of the arm. It is usual = to use a rigid light tubular arm. Lifting or lowering the arm a bit will provide a Cosine Theta correction to k, so you could see a few parts per thousand change.=20 =20 Usual values of the swing angle are about 1/3 degree for a 20 second period and a 24" arm. T =3D 2xPixSqrt(k / gxsin(A)) Avoid very short = arms, say 12". The value of A becomes very small and the pendulum will experience = tilt drift due to very small ground movements as the seasons, rainfall and temperatures change. You need to design your sensor system so that it's output is independent of any tilt drift. The layout of the sensor and the magnetic damping with the frame = should be your primary concern. =20 Regards, =20 Chris Chapman

Hi Chris, you got my attention when you talked about the = length of the arm and mass.=A0 Let’s say A’ is the pipe end of the = arm, B’ is the location of the mass (say 5 lbs) and “C” is the = location of the brass damping plate ( =BC lbs) on the original Lehman style design. = Using your calculation below, would you measure the 24” arm from = A’ to B’ or A’ to C’ ?=A0 Take a look at http:/= /pw2.netcom.com/~shammon1/compressed/e-w_Lehman.jpg and you will see why I am asking. When I was in San Jose I had two = Lehman’s with 36’ arms and the worked great and they had 20-25 second = periods without any effort. When I moved to Aptos I had to reduce the length to = 20” due to space issues and they have never performed as well as I = predicted. Now I’m wondering if I am measuring their arm length correctly.=A0=A0 = Comments?

Steve Hammond PSN Aptos, CA

 

From:= psn-l-request@.............. [mailto:psn-l-request@............... On = Behalf Of ChrisAtUpw@.......
Sent: Sunday, December 06, 2009 9:28 AM
To: psn-l@..............
Subject: Re: Adjusting a Lehman

 

In a message dated 06/12/2009, tchannel@............ = writes:

Hi Folks,   This is the basic process I use to = adj. a Lehman.

1.  I assembly everything and level everything.    Once this is completed the vertical part = of the frame is plumb.   The boom, and frame are parallel = with the earth and the boom is resting on the centreline.

2.  I time the period and start raising the front = adjusting leg, tweaking the side adj. legs as necessary to maintain the boom on = the centre line.  When I get a stable 20 second period I am = finished.

 

These are my questions:    When I = perform this set up, the vertical frame member is now tilting backward, and = the mass end of the boom has be raised.  Now the boom is no longer parallel = to the earth.

1.  "What would happen" if I extended the = wire support, lowering the boom back to parallel to the earth, but not = changing the vertical member.   To my knowledge I have never done this, I = just leave the boom with mass end raised via the front adj. = leg.

2.  Should I make this adjustment, returning the boom = to parallel, by lengthen the support wire?

I have tried it, but the adjustments are so small I can't = measure the results.

Hi Ted,

 

    The period is determined by 1) the = angle 'A' between the vertical and the true swing axis and by 2) the = radius of gyration 'k' of the pendulum. k depends on the weight and shape of the = mass and of the arm. It is usual to use a rigid light tubular arm. Lifting = or lowering the arm a bit will provide a Cosine Theta correction to k, so you could see a few parts per thousand = change. 

 

    Usual values of the swing angle are = about 1/3 degree for a 20 second period and a 24" arm. T =3D 2xPixSqrt(k = / gxsin(A)) Avoid very short arms, say 12". The value of A becomes = very small and the pendulum will experience tilt drift due to very small = ground movements as the seasons, rainfall and temperatures change. You = need to design your sensor system so that it's output is independent of any tilt = drift.

    The layout of the sensor and the = magnetic damping with the frame should be your primary = concern.

 

    Regards,

 

    Chris Chapman

Subject: RE: Integrating in WinQuake From: Randall Peters PETERS_RD@.......... Date: Mon, 7 Dec 2009 09:43:23 -0500 It is high time that everybody in the amateur seismology community (as well= as the professional one) understand something that is FUNDAMENTAL PHYSICS.= .. The ONLY thing that ANY seismometer's mechanical parts EVER respond to is= ACCELERATION. Let the skeptic of this claim go study not just Newton's law= s as treated in elementary textbooks, but also Einstein's principle of rela= tivity. The direct response to acceleration that I'm talking about is the m= otion of the instrument's main mass (called inertial) relative to the case = of the instrument. The only thing that can cause relative motion between th= ese two components of the instrument is acceleration of the case. The case = acceleration is the same as the acceleration of that part of the (local) ea= rth on which the instrument sits (at rest relative to this piece of earth).= The nature of the trace that is output from the instrument is determined n= ot only by this relative motion of these two mechanical components but also= by the nature of the electronics that monitors the motion. With a coil/mag= net (Faraday law) detector of classical type, the output voltage is proport= ional to the time rate of change (derivative) of the relative motion of mas= s and case. (assuming `flat electronics' for the amplifier circuits.) It is= a velocity sensor only in terms of what it is measuring; i.e., the relativ= e velocity of mass and case. This IS NOT, however, necessarily a measure of= the velocity of the local-earth itself. The earth velocity is the integral= of the acceleration of the earth. The nature of the instrument's response = to the earth's quintessential acceleration depends on the frequency of the = harmonic acceleration that causes an output. There are two parts to this ma= tter, both the frequency respnse of the mass/case and also the frequency re= sponse of the detector. The easiest mechanical type to understand is a simp= le pendulum. If the frequency of the earth's acceleration is lower than the= natural frequency of the pendulum, then the angular displacement of the pe= ndulum is proportional to the acceleration. For this frequency regime, the = coil/magnet output is therefore proportional to the derivative of local-ear= th acceleration. In engineering terminology, this is called a `jerk' detect= or. On the other hand, for local-earth acceleration frequencies higher tha= n the natural frequency of the pendulum, the output is indeed proportional = to the local-earth velocity. This is because the pendulum response to accel= eration for frequency higher than its natural frequency is proportional to = reciprocal frequency squared. Since Chris has mentioned the highly-esteemed= Erhard Wielandt, let me point out that Professor Wielandt has agreed with = me on this matter; i.e., the coil/magnet detector is a measure of local-ear= th velocity for harmonic motions having a frequency higher than the natural= frequency of the pendulum. Conversely, for frequencies lower than the natu= ral frequency, the detector is a jerk detector; i.e., it measures the time = derivative of the acceleration of the earth. Now concerning a capacitive de= tector, it is important that one understands the architecture with which it= is employed. With the VolksMeter, the most important to me (non-integrated= ) output is one in which the symmetric-differential-capacitive (SDC) detect= or measures the angular displacement of the pendulum. For earth's harmonic = accelerations that are at a frequency lower than the natural frequency of t= he VM (0.92 Hz), the pendulum response (and thus the SDC output) are propor= tionall to the earth's acceleration. One obtains then the earth's velocity = (for frequency less than 0.92 Hz) by integrating this SDC output. In the ca= se of a force-feedback instrument like those of STS type (influenced by the= expertise of Erhard Wielandt, built by Gunar Streckeisen), the output is g= overned by the poles/zeroes of the electronics designed to behave like a lo= ng-period-equivalent pendulum. The total system (`pendulum plus all of the = electronics) mimics that of a classical coil/magnet system monitoring a pen= dulum whose period is about 30 s. In other words, for earth accelerations i= n which the frequency is higher than the lower corner frequency of the STS = (approximately 0.03 Hz), the output is proportional to earth velocity. For = the spectral region of interest to many of us (teleseismic observations), o= ne thus sees that the integrated output of the VM can be compared directly = and meaningfully with the helicord display of conventional force balance se= nsors whose pendulum-equivalent natural frequency is no greater than about = 0.03 Hz. The same can be said of the garden-gate instruments that many of y= ou use, IF your period has been adjusted to be at least as great as 20 s. S= o can one talk about earth displacement or earth velocity or earth accelera= tion on the basis of what one's instrument is measuring? The answer is obvi= ously a qualified yes, but it is imperative that the transfer properties of= both the mechanical part (such as a pendulum) and also that of the electro= nics be properly factored into what is concluded. In summary, different sys= tems give different results concerning what is direct output, as opposed to= indirect, depending on the detector type. A capacitive sensor as used in t= he VM measures earth-acceleration directly for frequencies lower than 0.92 = Hz. STS instruments, though they use a capacitive sensor, but with sophisti= cated electronics involving an actuator, measure earth-velocity directly fo= r frequencies higher than about 0.03 Hz. Consequently, the integrated outpu= t from the VM can be compared directly with the output from an STS. Keep in= mind that integrating a second time may or may not yield earth displacemen= t, depending on the natural frequency of the instrument. One must `back out= ' the system response (total system transfer function) if the result is to = have any meaning. For those of you using geophones, where the natural frequ= ency is higher than 1 Hz; your output is proportional to the derivative of = earth acceleration. Relative to earth motion (not the geophone mass) your = detector is for frequencies of interest to most of us (not the local-enviro= nment high frequency parts) -- a jerk detector and not a velocity detector,= even though it uses a Farady law detector. Randall Peters

It is high time that everybody in the amateur seismology community (as w= ell as the professional one) understand something that is FUNDAMENTAL PHYSI= CS.. The ONLY thing that ANY seismometer's mechanical parts EVER respond to= is ACCELERATION. Let the skeptic of this claim go study not just Newton's laws as treated in elementary tex= tbooks, but also Einstein's principle of relativity. The direct response to= acceleration that I'm talking about is the motion of the instrument's main= mass (called inertial) relative to the case of the instrument. The only thing that can cause relative moti= on between these two components of the instrument is acceleration of the ca= se. The case acceleration is the same as the acceleration of that part of t= he (local) earth on which the instrument sits (at rest relative to this piece of earth). The nature of the trace th= at is output from the instrument is determined not only by this relative mo= tion of these two mechanical components but also by the nature of the elect= ronics that monitors the motion. With a coil/magnet (Faraday law) detector of classical type, the output vo= ltage is proportional to the time rate of change (derivative) of the relati= ve motion of mass and case. (assuming `flat electronics' for the amplifier = circuits.) It is a velocity sensor only in terms of what it is measuring; i.e., the relative velocity of mass= and case. This IS NOT, however, necessarily a measure of the velocity of t= he local-earth itself. The earth velocity is the integral of the accelerati= on of the earth. The nature of the instrument's response to the earth's quintessential acceleration depends o= n the frequency of the harmonic acceleration that causes an output. There a= re two parts to this matter, both the frequency respnse of the mass/case an= d also the frequency response of the detector. The easiest mechanical type to understand is a simple pendul= um. If the frequency of the earth's acceleration is lower than the natural = frequency of the pendulum, then the angular displacement of the pendulum is= proportional to the acceleration. For this frequency regime, the coil/magnet output is therefore proportiona= l to the derivative of local-earth acceleration. In engineering terminology= , this is called a `jerk' detector.  On the other hand, for local-eart= h acceleration frequencies higher than the natural frequency of the pendulum, the output is indeed proportional t= o the local-earth velocity. This is because the pendulum response to accele= ration for frequency higher than its natural frequency is proportional to r= eciprocal frequency squared. Since Chris has mentioned the highly-esteemed Erhard Wielandt, let me point out = that Professor Wielandt has agreed with me on this matter; i.e., the coil/m= agnet detector is a measure of local-earth velocity for harmonic motions ha= ving a frequency higher than the natural frequency of the pendulum. Conversely, for frequencies lower than = the natural frequency, the detector is a jerk detector; i.e., it measures t= he time derivative of the acceleration of the earth. Now concerning a capac= itive detector, it is important that one understands the architecture with which it is employed. With the = VolksMeter, the most important to me (non-integrated) output is one in whic= h the symmetric-differential-capacitive (SDC) detector measures the angular= displacement of the pendulum. For earth's harmonic accelerations that are at a frequency lower than the natu= ral frequency of the VM (0.92 Hz), the pendulum response (and thus the SDC = output) are proportionall to the earth's acceleration. One obtains then the= earth's velocity (for frequency less than 0.92 Hz) by integrating this SDC output. In the case of a force-= feedback instrument like those of STS type (influenced by the expertise of = Erhard Wielandt, built by Gunar Streckeisen), the output is governed b= y the poles/zeroes of the electronics designed to behave like a long-period-equivalent pendulum. The total syste= m (`pendulum plus all of the electronics) mimics that of a classical coil/m= agnet system monitoring a pendulum whose period is about 30 s. In othe= r words, for earth accelerations in which the frequency is higher than the lower corner frequency of the STS (a= pproximately 0.03 Hz), the output is proportional to earth velocity. For th= e spectral region of interest to many of us (teleseismic observations), one= thus sees that the integrated output of the VM can be compared directly and meaningfully with the helicord disp= lay of conventional force balance sensors whose pendulum-equivalent natural= frequency is no greater than about 0.03 Hz. The same can be said of t= he garden-gate instruments that many of you use, IF your period has been adjusted to be at least as g= reat as 20 s. So can one talk about earth displacement or earth velocity or= earth acceleration on the basis of what one's instrument is measuring? The= answer is obviously a qualified yes, but it is imperative that the transfer properties of both the mechanical part = (such as a pendulum) and also that of the electronics be properly factored = into what is concluded. In summary, different systems give different result= s concerning what is direct output, as opposed to indirect, depending on the detector type. A capacitive senso= r as used in the VM measures earth-acceleration directly for frequencies lo= wer than 0.92 Hz. STS instruments, though they use a capacitive sensor, but= with sophisticated electronics involving an actuator, measure earth-velocity directly for frequencies&nbs= p;higher than about 0.03 Hz. Consequently, the integrated output from the V= M can be compared directly with the output from an STS. Keep in mind that i= ntegrating a second time may or may not yield earth displacement, depending on the natural frequency of the instru= ment. One must `back out' the system response (total system transfer functi= on) if the result is to have any meaning. For those of you using geophones,= where the natural frequency is higher than 1 Hz; your output is proportional to the derivative of earth a= cceleration.  Relative to earth motion (not the geophone mass) your de= tector is for frequencies of interest to most of us (not the local-environm= ent high frequency parts) -- a jerk detector and not a velocity detector, even though it uses a Farady law detector.

    Randall Peters

Subject: VMGS From: "Ted Channel" tchannel@............ Date: Mon, 7 Dec 2009 08:05:23 -0700 Hello Friends, =20 I always enjoy looking at different sensor concepts. Sometimes = these ideas don't work out, or they are impractical. On the other hand = they sometimes do. I try as many different approaches as I can find. For anyone interested, I have a new sensor design, called a "Vertical = Mount, Garden gate, Seismic Sensor" VMGS. A reasonably simple = horizontal pendulum which functions like a Lehman. It is not a = Lehman, in that the support frame is different, but the pendulum moves = in the same way. It is not any easier or better than a Lehman, it is = just different...... I don't have a full set of dimensions, but I do have a word doc. = with pictures and a description. We are all busy and I don't want to = waste anyone's time, but of course I what to share this. If you are = interested, email me and I will send you a picture. If you are then = still curious, I will sent the entire file. tchannel@............... =20 Cheers, Ted =20

Hello=20 Friends,

 

     I always = enjoy looking=20 at different sensor concepts.  =20 Sometimes these ideas don=92t work out, or they are = impractical.  On the other hand they = sometimes=20 do.   I try as many = different=20 approaches as I can find.

   For anyone interested, I = have a=20 new sensor design, called a =93Vertical Mount, Garden gate, Seismic = Sensor=94  VMGS.   A reasonably simple = horizontal=20 pendulum which functions like a  Lehman.   It is not a Lehman, in = that the=20 support frame is different, but the pendulum moves in the same way.  It is not any easier or better = than a=20 Lehman, it is just = different=85=85=85=85=85.

     I don=92t = have a full=20 set of dimensions, but I do have a word doc. with pictures and a=20 description.   We are = all busy=20 and I don=92t want to waste anyone=92s time, but of course I what to = share=20 this.  If you are = interested, email=20 me and I will send you a picture.  =20 If you are then still curious, I will sent the entire file.  tchannel@............=20

 

Cheers,=20 Ted

    =20

Subject: Re: Integrating in WinQuake From: John Cole johncole0722@....... Date: Mon, 7 Dec 2009 08:00:19 -0800 (PST) Randall, as a rule I very seldom respond to articles on PSN however, this i= s a rare exception. Your opinion and thoughts on seismology=A0are right on = and when you express your opinions one knows you are completely correct . W= hat a refreshing article. I commend you my friend. John Cole, Pearland,Tx. = ..( amateur seismologist)=A0=0A=0A=0A=0A=0A________________________________= =0AFrom: Randall Peters =0ATo: "psn-l@.............."= =0ASent: Mon, December 7, 2009 8:43:23 AM=0ASubject:= RE: Integrating in WinQuake=0A=0A=0AIt is high time that everybody in the = amateur seismology community (as well as the professional one) understand s= omething that is FUNDAMENTAL PHYSICS.. The ONLY thing that ANY seismometer'= s mechanical parts EVER respond to is ACCELERATION. Let the skeptic of this= claim go study not just Newton's laws as treated in elementary textbooks, = but also Einstein's principle of relativity. The direct response to acceler= ation that I'm talking about is the motion of the instrument's main mass (c= alled inertial) relative to the case of the instrument. The only thing that= can cause relative motion between these two components of the instrument i= s acceleration of the case. The case acceleration is the same as the accele= ration of that part of the (local) earth on which the instrument sits (at r= est relative to this piece of earth). The nature of the trace that is outpu= t from the instrument is determined not only by this relative motion of the= se two mechanical components but also by the nature of the electronics that monitors the motion. With a= coil/magnet (Faraday law) detector of classical type, the output voltage i= s proportional to the time rate of change (derivative) of the relative moti= on of mass and case. (assuming `flat electronics' for the amplifier circuit= s.) It is a velocity sensor only in terms of what it is measuring; i.e., th= e relative velocity of mass and case. This IS NOT, however, necessarily a m= easure of the velocity of the local-earth itself. The earth velocity is the= integral of the acceleration of the earth. The nature of the instrument's = response to the earth's quintessential acceleration depends on the frequenc= y of the harmonic acceleration that causes an output. There are two parts t= o this matter, both the frequency respnse of the mass/case and also the fre= quency response of the detector. The easiest mechanical type to understand = is a simple pendulum. If the frequency of the earth's acceleration is lower than the natural frequency of the pendulum, then the angular disp= lacement of the pendulum is proportional to the acceleration. For this freq= uency regime, the coil/magnet output is therefore proportional to the deriv= ative of local-earth acceleration. In engineering terminology, this is call= ed a `jerk' detector.=A0 On the other hand, for local-earth acceleration fr= equencies higher than the natural frequency of the pendulum, the output is = indeed proportional to the local-earth velocity. This is because the pendul= um response to acceleration for frequency higher than its natural frequency= is proportional to reciprocal frequency squared. Since Chris has mentioned= the highly-esteemed Erhard Wielandt, let me point out that Professor Wiela= ndt has agreed with me on this matter; i.e., the coil/magnet detector is a = measure of local-earth velocity for harmonic motions having a frequency hig= her than the natural frequency of the pendulum. Conversely, for frequencies lower than the natural frequency, the detector is a jerk detec= tor; i.e., it measures the time derivative of the acceleration of the earth= .. Now concerning a capacitive detector, it is important that one understand= s the architecture with which it is employed. With the VolksMeter, the most= important to me (non-integrated) output is one in which the symmetric-diff= erential-capacitive (SDC) detector measures the angular displacement of the= pendulum. For earth's harmonic accelerations that are at a frequency lower= than the natural frequency of the VM (0.92 Hz), the pendulum response (and= thus the SDC output) are proportionall to the earth's acceleration. One ob= tains then the earth's velocity (for frequency less than 0.92 Hz) by integr= ating this SDC output. In the case of a force-feedback instrument like thos= e of STS type (influenced by the expertise of Erhard Wielandt, built by Gun= ar Streckeisen), the output is=A0governed by=A0the poles/zeroes of the electronics designed to behave like a long-period-equivalent pendulum. The= total system (`pendulum plus all of the electronics) mimics that of a clas= sical coil/magnet=A0system monitoring a pendulum whose period is about 30 s= .. In other words, for earth accelerations in which the frequency is=A0highe= r than the lower corner frequency of the STS (approximately 0.03 Hz), the o= utput is proportional to earth velocity. For the spectral region of interes= t to many of us (teleseismic observations), one thus sees that the integrat= ed output of the VM can be compared directly and meaningfully with the heli= cord display of conventional force balance sensors whose pendulum-equivalen= t natural frequency is no=A0greater than about 0.03 Hz. The same can be sai= d of the garden-gate instruments that many of you use, IF your period has b= een adjusted to=A0be at least as=A0great as 20 s. So can one talk about ear= th displacement or earth velocity or earth acceleration on the basis of what one's instrument is measuring? The answer is obviously a qualified ye= s, but it is imperative that the transfer properties of both the mechanical= part (such as a pendulum) and also that of the electronics be properly fac= tored into what is concluded. In summary, different systems give different = results concerning what is direct output, as opposed to indirect, depending= on the detector type. A capacitive sensor as used in the VM measures earth= -acceleration directly for frequencies lower than 0.92 Hz. STS instruments,= though they use a capacitive sensor, but with sophisticated electronics in= volving an actuator, measure earth-velocity directly for frequencies=A0high= er than about 0.03 Hz. Consequently, the integrated output from the VM can = be compared directly with the output from an STS. Keep in mind that integra= ting a second time may or may not yield earth displacement, depending on th= e natural frequency of the instrument. One must `back out' the system response (total system transfer function) if the result is to have any mea= ning. For those of you using geophones, where the natural frequency is high= er than 1 Hz; your output is proportional to the derivative of earth accele= ration.=A0 Relative to earth motion (not the geophone mass) your detector i= s for frequencies of interest to most of us (not the local-environment high= frequency parts) -- a jerk detector=A0and not=A0a velocity detector, even = though it uses a Farady law detector.=0A=A0=A0=A0 Randall Peters
Randall, as a rule I very seldom respond to articles o= n PSN however, this is a rare exception. Your opinion and thoughts on seism= ology are right on and when you express your opinions one knows you ar= e completely correct . What a refreshing article. I commend you my friend. = John Cole, Pearland,Tx. .( amateur seismologist) 
=0A
=0A
=0AFrom: Randall Peters <PETERS_RD@= mercer.edu>
To: "psn-= l@.............." <psn-l@..............>
Sent: Mon, December 7, 2009 8:43:23 AM
Subject: RE: Integrating in WinQuake<= BR>
=0A= =0A=0A=0A
=0AIt is high time that everybody in the amateur seismology community (as wel= l as the professional one) understand something that is FUNDAMENTAL PHYSICS= ... The ONLY thing that ANY seismometer's mechanical parts EVER respond to i= s ACCELERATION. Let the skeptic of this claim go study not just Newton's la= ws as treated in elementary textbooks, but also Einstein's principle of rel= ativity. The direct response to acceleration that I'm talking about is the = motion of the instrument's main mass (called inertial) relative to the case= of the instrument. The only thing that can cause relative motion between t= hese two components of the instrument is acceleration of the case. The case= acceleration is the same as the acceleration of that part of the (local) e= arth on which the instrument sits (at rest relative to this piece of earth)= .. The nature of the trace that is output from the instrument is determined = not only by this relative motion of these two mechanical components but also by the nature of the electronics that monitors the mot= ion. With a coil/magnet (Faraday law) detector of classical type, the outpu= t voltage is proportional to the time rate of change (derivative) of the re= lative motion of mass and case. (assuming `flat electronics' for the amplif= ier circuits.) It is a velocity sensor only in terms of what it is measurin= g; i.e., the relative velocity of mass and case. This IS NOT, however, nece= ssarily a measure of the velocity of the local-earth itself. The earth velo= city is the integral of the acceleration of the earth. The nature of the in= strument's response to the earth's quintessential acceleration depends on t= he frequency of the harmonic acceleration that causes an output. There are = two parts to this matter, both the frequency respnse of the mass/case and a= lso the frequency response of the detector. The easiest mechanical type to = understand is a simple pendulum. If the frequency of the earth's acceleration is lower than the natural frequency of the pendulum, then the= angular displacement of the pendulum is proportional to the acceleration. = For this frequency regime, the coil/magnet output is therefore proportional= to the derivative of local-earth acceleration. In engineering terminology,= this is called a `jerk' detector.  On the other hand, for local-earth= acceleration frequencies higher than the natural frequency of the pendulum= , the output is indeed proportional to the local-earth velocity. This is be= cause the pendulum response to acceleration for frequency higher than its n= atural frequency is proportional to reciprocal frequency squared. Since Chr= is has mentioned the highly-esteemed Erhard Wielandt, let me point out that= Professor Wielandt has agreed with me on this matter; i.e., the coil/magne= t detector is a measure of local-earth velocity for harmonic motions having= a frequency higher than the natural frequency of the pendulum. Conversely, for frequencies lower than the natural frequency, the detector= is a jerk detector; i.e., it measures the time derivative of the accelerat= ion of the earth. Now concerning a capacitive detector, it is important tha= t one understands the architecture with which it is employed. With the Volk= sMeter, the most important to me (non-integrated) output is one in which th= e symmetric-differential-capacitive (SDC) detector measures the angular dis= placement of the pendulum. For earth's harmonic accelerations that are at a= frequency lower than the natural frequency of the VM (0.92 Hz), the pendul= um response (and thus the SDC output) are proportionall to the earth's acce= leration. One obtains then the earth's velocity (for frequency less than 0.= 92 Hz) by integrating this SDC output. In the case of a force-feedback inst= rument like those of STS type (influenced by the expertise of Erhard Wielan= dt, built by Gunar Streckeisen), the output is governed by the poles/zeroes of the electronics designed to behave like a long= -period-equivalent pendulum. The total system (`pendulum plus all of the el= ectronics) mimics that of a classical coil/magnet system monitoring a = pendulum whose period is about 30 s. In other words, for earth acceleration= s in which the frequency is higher than the lower corner frequency of = the STS (approximately 0.03 Hz), the output is proportional to earth veloci= ty. For the spectral region of interest to many of us (teleseismic observat= ions), one thus sees that the integrated output of the VM can be compared d= irectly and meaningfully with the helicord display of conventional force ba= lance sensors whose pendulum-equivalent natural frequency is no greate= r than about 0.03 Hz. The same can be said of the garden-gate instruments t= hat many of you use, IF your period has been adjusted to be at least a= s great as 20 s. So can one talk about earth displacement or earth velocity or earth acceleration on the basis of what one's instrument= is measuring? The answer is obviously a qualified yes, but it is imperativ= e that the transfer properties of both the mechanical part (such as a pendu= lum) and also that of the electronics be properly factored into what is con= cluded. In summary, different systems give different results concerning wha= t is direct output, as opposed to indirect, depending on the detector type.= A capacitive sensor as used in the VM measures earth-acceleration directly= for frequencies lower than 0.92 Hz. STS instruments, though they use a cap= acitive sensor, but with sophisticated electronics involving an actuator, m= easure earth-velocity directly for frequencies higher than about 0.03 = Hz. Consequently, the integrated output from the VM can be compared directl= y with the output from an STS. Keep in mind that integrating a second time = may or may not yield earth displacement, depending on the natural frequency of the instrument. One must `back out' the system response (tota= l system transfer function) if the result is to have any meaning. For those= of you using geophones, where the natural frequency is higher than 1 Hz; y= our output is proportional to the derivative of earth acceleration.  R= elative to earth motion (not the geophone mass) your detector is for freque= ncies of interest to most of us (not the local-environment high frequency p= arts) -- a jerk detector and not a velocity detector, even though= it uses a Farady law detector.

=0A

  &n= bsp; Randall Peters

=0A

=0A
Subject: Re: Integrating in WinQuake From: Larry Conklin lconklin@............ Date: Mon, 07 Dec 2009 12:02:05 -0500 Randall Peters wrote: > > ..... I In engineering terminology, this is called a `jerk' detector. > ..... > > Well, that explains something I've been wondering about. Every time my sister-in-law's ex husband comes around, my system goes crazy. I guess it really is a jerk detector. Larry Conklin Liverpool, NY

Randall Peters wrote:

..... I In engineering terminology, this is called a `jerk' detector.  .....



Well, that explains something I've been wondering about.  Every time my sister-in-law's ex husband comes around, my system goes crazy.  I guess it really is a jerk detector.

Larry Conklin
Liverpool, NY

Subject: RE: Integrating in WinQuake From: RSparks rsparks@.......... Date: Wed, 09 Dec 2009 10:26:55 -0800 Hello Randall, Thanks for the informative posting relating sensors for seismometers. Here is an example that might complement the discussion. We all seem to agree that a coil/magnet sensor measures velocity and the displacement sensor measures location, both relative to boom and case. What I would like to add is that neither measurement completely defines conditions at the instant of measurement. The measurement of velocity ignores location, and measurement of location ignores the component of velocity. What we should do is to measure BOTH components (two sensors on each boom) at the same instant. Of course this would result in two data streams which would not be identical. For any one sine wave, maximum displacement would be measured when the velocity measurement was zero, and maximum velocity at a zero displacement measurement. If we want to relate the two measurements, we can easily see that the distance traveled between any two DISPLACEMENT measurements is the difference between the two measurements. This difference is also velocity when considered as distance per sample (which is distance per unit time). This can also be considered as the differential of the data. On the other hand, if we want to convert our VELOCITY readings to distance, we would need to find the average velocity between each of two measured velocities which would be the sum of the two velocities divided by two, also considered as the integral of the data. We can not expect to simply integrate the velocity data and obtain distance because we would be using the velocities measured at the distance points, not the average velocity that actually caused the resulting measured traveled distance. Now assume that we want to calculate acceleration from the DISPLACEMENT DATA. We would first calculate velocity by taking the difference between the two readings. Then we would take the difference between two of the velocity readings (a second differential of displacement) to find the velocity change per time per time. We would need at least three data points to make this series of calculations. To find acceleration from the VELOCITY data, we can not simply find the difference between two velocity readings (which is the velocity change per time per time (the first differential) ) because we would be using the velocities measured at distance points. Instead, we should find the average velocity between two points and then find the difference between that average velocity and a previous average velocity to reach an average acceleration. Again, three data points would be required. We should notice that both of these processes to find acceleration are frequency sensitive and will suppress higher frequency data fluctuation's. Finally, let us consider the STS device with a degenerative feedback system installed. Our two sensors would register nearly zero output because the feedback system works to minimize both velocity and travel of the boom. As a result, energy as found in the kinetic energy of velocity or energy in a spring is not allowed to be stored. The reduced storage energy can be expected to minimize the carry-over of energy from one data sample to another, thus reducing distortion of the true wave form of the seismic disturbance. When a displacement sensor is used to generate the feedback signal, the resultant trace should still be a displacement location. When a velocity sensor is used to generate the feedback signal, the resultant trace should still be a velocity trace but the output should about 1.4 times higher than the externally damped velocity output because (nearly) all of the incoming energy is available to generate a detectable reading (rather than being stored in the boom as kinetic energy or in the spring as potential energy). Unfortunately, I do not have an STS device so I can not test this explanation. Perhaps you or others can enlighten us about the correctness or failure of this conjecture. Food for thought, Roger __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: displacement From: "Ted Channel" tchannel@............ Date: Wed, 9 Dec 2009 12:53:08 -0700 Hi Folks, Some while back I saw a graph showing how much a pendulum = moved during an earthquake. I am not sure if it was shown in = nanometer. Could someone direct me to it again? Thanks, Ted
Hi Folks,  Some while back I saw a = graph=20 showing how much a pendulum moved during an earthquake.   I am = not=20 sure if it was shown in nanometer.  Could someone direct me to it=20 again?
Thanks, Ted
Subject: Re: Integrating in WinQuake From: "Geoffrey" gmvoeth@........... Date: Wed, 9 Dec 2009 14:54:32 -0700 I am NO expert yet do have some experience with this seismic stuff, It is not necessary to worry so much what is doing the sensing so long as you see a nice signal coming in that gives a classic EQ signature. The only better thing to do is to do exactly the same thing for all three axises simultaneously then you can get a single magnitude to look at as a vectored sum. But you need three different A/D converters all working in synchronous step collecting each sample ( all three) at the very same time. Then you may use math to sort out the final display. In absecence of this ability I simply settle for a Magnet/Coil Vertical SPZ which is by far the simplest for an Amature. Writing your own programs can be fun. What is fine for a teenager here seems fine for me. Even tho Im no teenager. Thanks if anyone listened at all :-) geoff [GVA] ----- Original Message ----- From: "RSparks" To: Sent: Wednesday, December 09, 2009 11:26 AM Subject: RE: Integrating in WinQuake > Hello Randall, > > Thanks for the informative posting relating sensors for seismometers. > > Here is an example that might complement the discussion. > > We all seem to agree that a coil/magnet sensor measures velocity and the displacement sensor measures location, both relative to > boom and case. What I would like to add is that neither measurement completely defines conditions at the instant of measurement. > The measurement of velocity ignores location, and measurement of location ignores the component of velocity. What we should do is > to measure BOTH components (two sensors on each boom) at the same instant. Of course this would result in two data streams which > would not be identical. For any one sine wave, maximum displacement would be measured when the velocity measurement was zero, > and maximum velocity at a zero displacement measurement. > > If we want to relate the two measurements, we can easily see that the distance traveled between any two DISPLACEMENT measurements > is the difference between the two measurements. This difference is also velocity when considered as distance per sample (which is > distance per unit time). This can also be considered as the differential of the data. > On the other hand, if we want to convert our VELOCITY readings to distance, we would need to find the average velocity between > each of two measured velocities which would be the sum of the two velocities divided by two, also considered as the integral of > the data. We can not expect to simply integrate the velocity data and obtain distance because we would be using the velocities > measured at the distance points, not the average velocity that actually caused the resulting measured traveled distance. > > Now assume that we want to calculate acceleration from the DISPLACEMENT DATA. We would first calculate velocity by taking the > difference between the two readings. Then we would take the difference between two of the velocity readings (a second > differential of displacement) to find the velocity change per time per time. We would need at least three data points to make > this series of calculations. > > To find acceleration from the VELOCITY data, we can not simply find the difference between two velocity readings (which is the > velocity change per time per time (the first differential) ) because we would be using the velocities measured at distance points. > Instead, we should find the average velocity between two points and then find the difference between that average velocity and a > previous average velocity to reach an average acceleration. Again, three data points would be required. > > We should notice that both of these processes to find acceleration are frequency sensitive and will suppress higher frequency data > fluctuation's. > > Finally, let us consider the STS device with a degenerative feedback system installed. Our two sensors would register nearly zero > output because the feedback system works to minimize both velocity and travel of the boom. As a result, energy as found in the > kinetic energy of velocity or energy in a spring is not allowed to be stored. The reduced storage energy can be expected to > minimize the carry-over of energy from one data sample to another, thus reducing distortion of the true wave form of the seismic > disturbance. When a displacement sensor is used to generate the feedback signal, the resultant trace should still be a > displacement location. When a velocity sensor is used to generate the feedback signal, the resultant trace should still be a > velocity trace but the output should about 1.4 times higher than the externally damped velocity output because (nearly) all of > the incoming energy is available to generate a detectable reading (rather than being stored in the boom as kinetic energy or in > the spring as potential energy). > > Unfortunately, I do not have an STS device so I can not test this explanation. Perhaps you or others can enlighten us about the > correctness or failure of this conjecture. > > Food for thought, > > Roger > > > > > > > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: RE: Integrating in WinQuake From: Kevin Brunt k.brunt@......... Date: Wed, 9 Dec 2009 21:56:41 +0000 (GMT Standard Time) Hi, I'm a little uncomfortable with your discussion. However, this may just be because it's a bit involved. It should be obvious that if you have a regular stream of data points from a displacement sensor, you can plot the velocity (in arbitrary units) on the same graph by computing the difference in displacement between two points and plotting the points of the new curve "in between" the displacement points. You can then repeat the process on the velocity points to get acceleration. The really important point, however, is to consider a simple pendulum, and realise that the acceleration is due to the force acting on the pendulum, which has nothing to do directly with the forces acting to move the pendulum support, but entirely on how far the pendulum mass is displaced from the "rest" position. This is Prof Peters' point about acceleration. I don't find the references to energy helpful. At the end of the day, the kinetic energy is eventually dumped into the damping. If I understand force-feedback correctly, it can be crudely summarised by noting that whereas a simple pendulum swings, FFB holds the mass still and the simple analogue computer that comprises the fedback circuit swings instead, with the force applied to the mass (= acceleration) being measured at the output to the feedback coil (or equivalent) as the sensor output. Kevin Brunt On Wed, 09 Dec 2009 10:26:55 -0800 RSparks wrote: > Hello Randall, > > Thanks for the informative posting relating sensors for seismometers. > > Here is an example that might complement the discussion. > > We all seem to agree that a coil/magnet sensor measures velocity and the > displacement sensor measures location, both relative to boom and case. > What I would like to add is that neither measurement completely defines > conditions at the instant of measurement. The measurement of velocity > ignores location, and measurement of location ignores the component of > velocity. What we should do is to measure BOTH components (two sensors > on each boom) at the same instant. Of course this would result in two > data streams which would not be identical. For any one sine wave, > maximum displacement would be measured when the velocity measurement was > zero, and maximum velocity at a zero displacement measurement. > > If we want to relate the two measurements, we can easily see that the > distance traveled between any two DISPLACEMENT measurements is the > difference between the two measurements. This difference is also > velocity when considered as distance per sample (which is distance per > unit time). This can also be considered as the differential of the data. > > On the other hand, if we want to convert our VELOCITY readings to > distance, we would need to find the average velocity between each of two > measured velocities which would be the sum of the two velocities divided > by two, also considered as the integral of the data. We can not expect > to simply integrate the velocity data and obtain distance because we > would be using the velocities measured at the distance points, not the > average velocity that actually caused the resulting measured traveled > distance. > > Now assume that we want to calculate acceleration from the DISPLACEMENT > DATA. We would first calculate velocity by taking the difference > between the two readings. Then we would take the difference between two > of the velocity readings (a second differential of displacement) to find > the velocity change per time per time. We would need at least three > data points to make this series of calculations. > > To find acceleration from the VELOCITY data, we can not simply find the > difference between two velocity readings (which is the velocity change > per time per time (the first differential) ) because we would be using > the velocities measured at distance points. Instead, we should find the > average velocity between two points and then find the difference between > that average velocity and a previous average velocity to reach an > average acceleration. Again, three data points would be required. > > We should notice that both of these processes to find acceleration are > frequency sensitive and will suppress higher frequency data fluctuation's. > > Finally, let us consider the STS device with a degenerative feedback > system installed. Our two sensors would register nearly zero output > because the feedback system works to minimize both velocity and travel > of the boom. As a result, energy as found in the kinetic energy of > velocity or energy in a spring is not allowed to be stored. The reduced > storage energy can be expected to minimize the carry-over of energy from > one data sample to another, thus reducing distortion of the true wave > form of the seismic disturbance. When a displacement sensor is used to > generate the feedback signal, the resultant trace should still be a > displacement location. When a velocity sensor is used to generate the > feedback signal, the resultant trace should still be a velocity trace > but the output should about 1.4 times higher than the externally damped > velocity output because (nearly) all of the incoming energy is > available to generate a detectable reading (rather than being stored in > the boom as kinetic energy or in the spring as potential energy). > > Unfortunately, I do not have an STS device so I can not test this > explanation. Perhaps you or others can enlighten us about the > correctness or failure of this conjecture. > > Food for thought, > > Roger __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: displacement From: "Geoffrey" gmvoeth@........... Date: Wed, 9 Dec 2009 15:02:04 -0700 I will bet a can of navy beans that no passive device will show relative movement that is as much as the ground really moves. ----- Original Message ----- From: "Ted Channel" To: "psn" Sent: Wednesday, December 09, 2009 12:53 PM Subject: displacement Hi Folks, Some while back I saw a graph showing how much a pendulum moved during an earthquake. I am not sure if it was shown in nanometer. Could someone direct me to it again? Thanks, Ted __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: RE: Integrating in WinQuake From: "Geoffrey" gmvoeth@........... Date: Wed, 9 Dec 2009 15:12:03 -0700 It seems to me that if you could precisely measure energy only in damping the thing it would possibly give you the very best results. You would then be looking only at energy imparted on the device in ergs per microsecond or whatever and nothing else. Energy is sort of like how far did the bullet make that log rise during the bullets inelastic collision with the log on four strings. It has nothing to do with the dampened oscillations after the collision. it strikes me hard that the USGS uses energy to judge earthquakes then possibly so should we ?? Is there a energy way to see earthquakes, maybe an FFT display ? ----- Original Message ----- From: "Kevin Brunt" To: Sent: Wednesday, December 09, 2009 2:56 PM Subject: Re: RE: Integrating in WinQuake > > Hi, > > I'm a little uncomfortable with your discussion. However, this may just be > because it's a bit involved. > > It should be obvious that if you have a regular stream of data points from a > displacement sensor, you can plot the velocity (in arbitrary units) on the same > graph by computing the difference in displacement between two points and > plotting the points of the new curve "in between" the displacement points. You > can then repeat the process on the velocity points to get acceleration. > > The really important point, however, is to consider a simple pendulum, and > realise that the acceleration is due to the force acting on the pendulum, which > has nothing to do directly with the forces acting to move the pendulum support, > but entirely on how far the pendulum mass is displaced from the "rest" position. > > This is Prof Peters' point about acceleration. > > I don't find the references to energy helpful. At the end of the day, the > kinetic energy is eventually dumped into the damping. > > If I understand force-feedback correctly, it can be crudely summarised by > noting that whereas a simple pendulum swings, FFB holds the mass still and the > simple analogue computer that comprises the fedback circuit swings instead, > with the force applied to the mass (= acceleration) being measured at the > output to the feedback coil (or equivalent) as the sensor output. > > Kevin Brunt > > On Wed, 09 Dec 2009 10:26:55 -0800 RSparks wrote: > >> Hello Randall, >> >> Thanks for the informative posting relating sensors for seismometers. >> >> Here is an example that might complement the discussion. >> >> We all seem to agree that a coil/magnet sensor measures velocity and the >> displacement sensor measures location, both relative to boom and case. >> What I would like to add is that neither measurement completely defines >> conditions at the instant of measurement. The measurement of velocity >> ignores location, and measurement of location ignores the component of >> velocity. What we should do is to measure BOTH components (two sensors >> on each boom) at the same instant. Of course this would result in two >> data streams which would not be identical. For any one sine wave, >> maximum displacement would be measured when the velocity measurement was >> zero, and maximum velocity at a zero displacement measurement. >> >> If we want to relate the two measurements, we can easily see that the >> distance traveled between any two DISPLACEMENT measurements is the >> difference between the two measurements. This difference is also >> velocity when considered as distance per sample (which is distance per >> unit time). This can also be considered as the differential of the data. >> >> On the other hand, if we want to convert our VELOCITY readings to >> distance, we would need to find the average velocity between each of two >> measured velocities which would be the sum of the two velocities divided >> by two, also considered as the integral of the data. We can not expect >> to simply integrate the velocity data and obtain distance because we >> would be using the velocities measured at the distance points, not the >> average velocity that actually caused the resulting measured traveled >> distance. >> >> Now assume that we want to calculate acceleration from the DISPLACEMENT >> DATA. We would first calculate velocity by taking the difference >> between the two readings. Then we would take the difference between two >> of the velocity readings (a second differential of displacement) to find >> the velocity change per time per time. We would need at least three >> data points to make this series of calculations. >> >> To find acceleration from the VELOCITY data, we can not simply find the >> difference between two velocity readings (which is the velocity change >> per time per time (the first differential) ) because we would be using >> the velocities measured at distance points. Instead, we should find the >> average velocity between two points and then find the difference between >> that average velocity and a previous average velocity to reach an >> average acceleration. Again, three data points would be required. >> >> We should notice that both of these processes to find acceleration are >> frequency sensitive and will suppress higher frequency data fluctuation's. >> >> Finally, let us consider the STS device with a degenerative feedback >> system installed. Our two sensors would register nearly zero output >> because the feedback system works to minimize both velocity and travel >> of the boom. As a result, energy as found in the kinetic energy of >> velocity or energy in a spring is not allowed to be stored. The reduced >> storage energy can be expected to minimize the carry-over of energy from >> one data sample to another, thus reducing distortion of the true wave >> form of the seismic disturbance. When a displacement sensor is used to >> generate the feedback signal, the resultant trace should still be a >> displacement location. When a velocity sensor is used to generate the >> feedback signal, the resultant trace should still be a velocity trace >> but the output should about 1.4 times higher than the externally damped >> velocity output because (nearly) all of the incoming energy is >> available to generate a detectable reading (rather than being stored in >> the boom as kinetic energy or in the spring as potential energy). >> >> Unfortunately, I do not have an STS device so I can not test this >> explanation. Perhaps you or others can enlighten us about the >> correctness or failure of this conjecture. >> >> Food for thought, >> >> Roger > > > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: displacement From: "Dale Hardy" photon1@........... Date: Thu, 10 Dec 2009 10:05:07 +1100 Ted, John Lahr had a spreadsheet on ground motion amplitude, that may = assist you regards Dale http://jclahr.com/science/psn/magnitude_files/ML_magnitude.xls ----- Original Message -----=20 From: Ted Channel=20 To: psn=20 Sent: Thursday, December 10, 2009 6:53 AM Subject: displacement Hi Folks, Some while back I saw a graph showing how much a pendulum = moved during an earthquake. I am not sure if it was shown in = nanometer. Could someone direct me to it again? Thanks, Ted
Ted, John Lahr had a spreadsheet on = ground motion=20 amplitude, that may assist you
regards
Dale
h= ttp://jclahr.com/science/psn/magnitude_files/ML_magnitude.xls<= /DIV>
 
----- Original Message -----
From:=20 Ted=20 Channel
To: psn
Sent: Thursday, December 10, = 2009 6:53=20 AM
Subject: displacement

Hi Folks,  Some while back I saw = a graph=20 showing how much a pendulum moved during an earthquake.   I = am not=20 sure if it was shown in nanometer.  Could someone direct me to it = again?
Thanks, = Ted
Subject: Re: displacement From: "Ted Channel" tchannel@............ Date: Wed, 9 Dec 2009 17:13:46 -0700 Yes, Thanks, that is it. Ted ----- Original Message -----=20 From: Dale Hardy=20 To: psn-l@................. Sent: Wednesday, December 09, 2009 4:05 PM Subject: Re: displacement Ted, John Lahr had a spreadsheet on ground motion amplitude, that may = assist you regards Dale http://jclahr.com/science/psn/magnitude_files/ML_magnitude.xls ----- Original Message -----=20 From: Ted Channel=20 To: psn=20 Sent: Thursday, December 10, 2009 6:53 AM Subject: displacement Hi Folks, Some while back I saw a graph showing how much a pendulum = moved during an earthquake. I am not sure if it was shown in = nanometer. Could someone direct me to it again? Thanks, Ted
Yes, Thanks, that is it.
Ted
----- Original Message -----
From:=20 Dale Hardy=20
Sent: Wednesday, December 09, = 2009 4:05=20 PM
Subject: Re: displacement

Ted, John Lahr had a spreadsheet on = ground motion=20 amplitude, that may assist you
regards
Dale
h= ttp://jclahr.com/science/psn/magnitude_files/ML_magnitude.xls<= /DIV>
 
----- Original Message -----
From:=20 Ted=20 Channel
To: psn
Sent: Thursday, December 10, = 2009 6:53=20 AM
Subject: displacement

Hi Folks,  Some while back I = saw a graph=20 showing how much a pendulum moved during an earthquake.   = I am not=20 sure if it was shown in nanometer.  Could someone direct me to = it=20 again?
Thanks,=20 Ted
Subject: Geoffrey Cant Post EVENT files Files To PSN anymore ??? From: "Geoffrey" gmvoeth@........... Date: Wed, 9 Dec 2009 18:50:18 -0700 Does this mean the EVENT server is down or am I sending to the wrong place OR am I being Blocked ? Its been like this several days now. In the mean time I rebuilt my system. What is stopping my posts to seismicnet server ? Tracing route to seismicnet.com [66.92.4.80] over a maximum of 30 hops: 9 45 ms 39 ms 36 ms ae-2.ebr3.SanJose1.Level3.net [4.69.132.9] 10 37 ms 35 ms 39 ms ae-73-73.csw2.SanJose1.Level3.net [4.69.134.230] 11 37 ms 33 ms 31 ms ae-21-79.car1.SanJose1.Level3.net [4.68.18.67] 12 33 ms 30 ms 35 ms unknown.Level3.net [209.247.156.222] 13 56 ms 36 ms 34 ms 220.ge-3-0.er1.sfo1.speakeasy.net [69.17.83.178] 14 * * * Request timed out. Thanks For any answers. geoff __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: RE: Geoffrey Cant Post EVENT files Files To PSN anymore ??? From: RSparks rsparks@.......... Date: Fri, 11 Dec 2009 05:55:38 -0800 Hello Geoff, I had this problem one time. I had been modifying Amaseis and had an error(s) in the PSN-type-4 file format that caused problems with Larry's web site. He found it necessary to block me from posting but was not able to tell from the file who was sending the file so he was unable to advise me that I had a problem. Of course, I do not know if you are blocked or not, but it happened to me for justifiable reasons. I use WinQuake to modify my PSN-type-4 files generated by Amaseis, but station info arrives to WinQuake having been hard coded into the Amaseis generated file. As I remember, the errors occurred because my hard coded information was incomplete so that WinQuake was not seeing a complete and properly formated header before Winquake found data. Grievous errors resulted. Hope this helps, good luck, Roger > .------ ------ ------ ------ ------ ------ ------ ------ ------ ------. > | Message 9 | > '------ ------ ------ ------ ------ ------ ------ ------ ------ ------' > Subject: Geoffrey Cant Post EVENT files Files To PSN anymore ??? > From: "Geoffrey" > Date: Wed, 9 Dec 2009 18:50:18 -0700 > > Does this mean the EVENT server is down > or am I sending to the wrong place > OR am I being Blocked ? > > Its been like this several days now. > > In the mean time I rebuilt my system. > > What is stopping my posts to seismicnet server ? > > Tracing route to seismicnet.com [66.92.4.80] > over a maximum of 30 hops: > 9 45 ms 39 ms 36 ms ae-2.ebr3.SanJose1.Level3.net [4.69.132.9] > 10 37 ms 35 ms 39 ms ae-73-73.csw2.SanJose1.Level3.net [4.69.134.230] > 11 37 ms 33 ms 31 ms ae-21-79.car1.SanJose1.Level3.net [4.68.18.67] > 12 33 ms 30 ms 35 ms unknown.Level3.net [209.247.156.222] > 13 56 ms 36 ms 34 ms 220.ge-3-0.er1.sfo1.speakeasy.net [69.17.83.178] > 14 * * * Request timed out. > > Thanks For any answers. > geoff > > > > > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-DIGEST-REQUEST@.............. with > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. > > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Earthquake probalility From: "Ted Channel" tchannel@............ Date: Fri, 11 Dec 2009 07:27:08 -0700 http://geohazards.usgs.gov/eqprob/2009/ I just found = this.............Hope you find it interesting also. The input lat. and = long. fields are limited. Ted
http://geohazards.usgs.g= ov/eqprob/2009/   =20 I just found this.............Hope you find it interesting = also.   The=20 input lat. and long. fields are limited.
 
Ted
Subject: Programming Basic Compiler For Windows From: "Geoffrey" gmvoeth@........... Date: Fri, 11 Dec 2009 18:25:55 -0700 FYI, I'm not trying to push anything on you guys at PSN but if you want to do your own programming I understand Power Basic people are now selling their older VERSION 8 Windows compiler for only $49.00 its what I'm using now and I know of nothing better for that price. I will not give you the exact email for the fear you would call it spam but I like this power basic since its like the old days when Microsoft gave you qbasic with MSDOS. Possibly you can get VBASIC for free from Microsoft but not sure there. I think I downloaded a whole sweet of compilers from them Vbasic/C++ yet since am already hooked on powerbasic will not change. I hated C++ it is in between assembly and BASIC and is more intolerant of mistakes. C++ has a learning curve that is steeper to climb. You will not be well rounded without all three but who cares since we are only amatures here at PSN. If you are interested in the details give me a direct address and I will forward you a copy of the email they sent me. Dont get me wrong here because PowerBasic can still nickle/dime you to death with all their extras. But for a compiler program I like their product quite well. I paid 4 times this much at least for what I have today. __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Geoffrey Cant Post EVENT files Files To PSN anymore ??? From: "Geoffrey" gmvoeth@........... Date: Fri, 11 Dec 2009 18:50:32 -0700 Thank you RSparks, Larry already pointed me to the right solution when he mentioned MIME for Email. I had designated my Windows Mail Client to use UUENCODE instead of B64 ( MIME ) encoding and the seems to be the cause. UUENCODE is an older method of posting 8 bit binaries to 7 bit news groups. MIME or B64 encoding is what is used most today in the USA. When I changed my email back to MIME (OR B64) the EVENT site would then accept my posts. I believe I have worked out Larry's Header fine now and am converting my data easily to acceptable Winquake form. I must have made a mole of versions to get it right though. It took me quite a while even though he tells you exactly how to do it ??? WINZIP will handle B64 files nicely. You just cut and paste it from the Properties then give it a name of Whatever.b64 and Winquake will unscramble it back to 8 bit for you. There are three main encoders I know of being (MIME being something.B64) (UUENCODE UUDECODE for something.UUE) (BINHEX for something.HQX). They all take 8 bit files and convert them to 7 bit for news groups. The News groups only allow 7 bit data to be posted so nothing can be executable but only text characters. Dates back to the 1980s or before. These people are really really paranoid as can explain why the common PC is so horribly designed with PROTECTED MODE MEMORY. In my mind there is nothing like straight line memory where anything can go anywhere as fast as possible. I saw an USN NTDS computer in the 1970s that was better then the kind of stuff I see today with its protected garbage. Sort of like a DEC PDP1140 industrial computer. Regards; geoff ----- Original Message ----- From: "RSparks" To: Sent: Friday, December 11, 2009 6:55 AM Subject: RE: Geoffrey Cant Post EVENT files Files To PSN anymore ??? > Hello Geoff, > > I had this problem one time. I had been modifying Amaseis and had an > error(s) in the PSN-type-4 file format that caused problems with Larry's > web > site. He found it necessary to block me from posting but was not able > to tell from the file who was sending the file so he was unable to > advise me that I had a problem. Of course, I do not know if you are > blocked or not, but it happened to me for justifiable reasons. > > I use WinQuake to modify my PSN-type-4 files generated by Amaseis, but > station info arrives to WinQuake having been hard coded into the Amaseis > generated file. As I remember, the errors occurred because my hard > coded information was incomplete so that WinQuake was not seeing a > complete and properly formated header before Winquake found data. > Grievous errors resulted. > > Hope this helps, good luck, > > Roger >> .------ ------ ------ ------ ------ ------ ------ ------ ------ ------. >> | Message 9 | >> '------ ------ ------ ------ ------ ------ ------ ------ ------ ------' >> Subject: Geoffrey Cant Post EVENT files Files To PSN anymore ??? >> From: "Geoffrey" >> Date: Wed, 9 Dec 2009 18:50:18 -0700 >> >> Does this mean the EVENT server is down >> or am I sending to the wrong place >> OR am I being Blocked ? >> >> Its been like this several days now. >> >> In the mean time I rebuilt my system. >> >> What is stopping my posts to seismicnet server ? >> >> Tracing route to seismicnet.com [66.92.4.80] >> over a maximum of 30 hops: >> 9 45 ms 39 ms 36 ms ae-2.ebr3.SanJose1.Level3.net [4.69.132.9] >> 10 37 ms 35 ms 39 ms ae-73-73.csw2.SanJose1.Level3.net [4.69.134.230] >> 11 37 ms 33 ms 31 ms ae-21-79.car1.SanJose1.Level3.net [4.68.18.67] >> 12 33 ms 30 ms 35 ms unknown.Level3.net [209.247.156.222] >> 13 56 ms 36 ms 34 ms 220.ge-3-0.er1.sfo1.speakeasy.net [69.17.83.178] >> 14 * * * Request timed out. >> >> Thanks For any answers. >> geoff >> >> >> >> >> __________________________________________________________ >> >> Public Seismic Network Mailing List (PSN-L) >> >> To leave this list email PSN-L-DIGEST-REQUEST@.............. with >> the body of the message (first line only): unsubscribe >> See http://www.seismicnet.com/maillist.html for more information. >> >> > > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Google Quakes From: Barry Lotz barry_lotz@............. Date: Fri, 11 Dec 2009 20:18:24 -0800 (PST) All I was trying to fill in data for events I had recorded in the past and I ran into this USGS site. Interesting site. http://neic.usgs.gov/neis/epic/kml/ Regards Barry http://www.seismicvault.com
All
I was trying to fill in data for events I had recorded in the past and I ran into this USGS site. Interesting site.

http://neic.usgs.gov/neis/epic/kml/

Regards
Barry
http://www.seismicvault.com
Subject: Winquake event report From: Barry Lotz barry_lotz@............. Date: Tue, 15 Dec 2009 21:58:15 -0800 (PST) All I have been trying to fill in my historical event data into winquake. I can= manually enter the data but it's time consuming. I found this web site whe= re I can get data but I am not sure how to modify the report.dat/ network.d= at=A0 to include an appropriate format that winquake will recognize or how = to tag an existing format for the event report the website creates. http://www.ncedc.org/anss/catalog-search.html Regards Barry http://www.seismicvault.com Subject: Winquake event report From: Barry Lotz barry_lotz@............. Date: Tue, 15 Dec 2009 22:58:45 -0800 (PST) All =A0It looks like if I request the report from the website in an 80 column f= ormat and obtain it via anonymous ftp it will be read OK in Winquake using = the "Berkeley seismic data center " type of report. http://www.ncedc.org/anss/catalog-search.html Regards Barry http://www.seismicvault.com
All
I have been t= rying to fill in my historical event data into winquake. I can manually ent= er the data but it's time consuming. I found this web site where I can get = data but I am not sure how to modify the report.dat/ network.dat  to i= nclude an appropriate format that winquake will recognize or how to tag an = existing format for the event report the website creates.

http://www.ncedc= ..org/anss/catalog-search.html

Regards
Barry
http://www.seismicvault.com
All
 It look= s like if I request the report from the website in an 80 column format and = obtain it via anonymous ftp it will be read OK in Winquake usi= ng the "Berkeley seismic data center " type of report.

http://www.ncedc.or= g/anss/catalog-search.html

Regards
Barry
http://www.seismicva= ult.com
Subject: Compound Vertical From: "Ted Channel" tchannel@............ Date: Sat, 19 Dec 2009 11:34:43 -0700 http://www.iris.washington.edu/stations/seisWorkshop04/PDF/CompoundVertic= alSeismometer.pdf I just found this. If Mr. Peters, or anyone can = tell me more about this, please email me. Thanks, Ted
http://www.iris.washington.edu/stations/seisWo= rkshop04/PDF/CompoundVerticalSeismometer.pdf   =20 I just found this.   If Mr. Peters, or anyone can tell me more = about=20 this, please email me.
 
Thanks, Ted
Subject: compound vertical seismometer From: Randall Peters PETERS_RD@.......... Date: Sun, 20 Dec 2009 08:44:14 -0500 Ted, The vertical seismometer that I showed at the broadband conference in 2= 004 http://www.iris.edu/stations/seisWorkshop04/seisWorkshop.htm, which you ref= erenced by http://www.iris.washington.edu/stations/seisWorkshop04/PDF/CompoundVertical= Seismometer.pdf operates on the principle of the archer's compound bow. I published a pa= per in 2000 concerned with the physics of the compound bow, titled "Archer'= s compound bow, smart use of nonlinearity". It is online at http://physics= ..mercer.edu/petepag/combow.html. Because of force reduction at full draw, due to the eccentrics (cams), = the bow concept can be used to lengthen the period of a similarly operating= seismometer. John Nelson asked about this possibility in a mailing to the= listserve in 2003, to which Chris Chapman responded http://www.seismicnet.com/psnlist/030502_055148_1.html For additional pictures of the prototype that I built, you may go to my= webpage at http://physics.mercer.edu/petepag/cvs.html The sensor employed in this prototype is one of my fully-differential ca= pacitive forms, but other types (such as coil/magnet) could be used. As Ch= ris has frequently pointed out, if you were to use the Faraday law sensor, = it is important that the coil (not the magnet) be the moving part. I never had time to pursue this concept the way I wanted to, but the da= ta that was presented at the IRIS-sponsored conference (first reference abo= ve) shows that it has promise--especially if you were to build one a lot bi= gger. I wanted to try this with an elastic element using carbon epoxy elem= ents in some arrangement, but never got around to it. Incidently, the firs= t one of these ever built was by one of my students when I was at Texas Tec= h University, around 1997. It was much larger and used a coil spring (appr= oximately LaCoste zero-length type) instead of the torsion wires of the pro= totype, but I never got around to seriously using it, since I moved to Merc= er University soon thereafter. =20 You may be interested to know that Erhard Wielandt, who was at the conf= erence, encouraged me to try and get amateur seismologists interested in us= ing the ideas. A number of the folks there were very curious about the ins= trument, since it had been setup on a table and made quasi-functional. =20 Randall= __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: compound vertical seismometer From: "Ted Channel" tchannel@............ Date: Sun, 20 Dec 2009 07:31:43 -0700 Dear Dr. Peters, Thank you for taking the time to respond. I am not much of a scientist, more of a builder. I get a big kick from trying different approaches to seismometers. http://sites.google.com/site/tchannelproject/seismic-sensors My web site is primitive, but there you can see pictures of some of the sensors I have built. Not shown are my torsion springs sensors. I have done several, and they have worked out well. Your idea is amassing to me. I would like to give it a try, but before I begin, and if you have time could you explain the math. In the pdf file, fig. 4, axis offset (r/R).....on the left side if we point to 11, is this 11x R= arm length, cm? and R being the alum. tube radius. Could you give me an example for the dimensions, r, R, and arm length, assuming the cylinder is 3.8cm id? Basically, what I am after, is a starting point.......and if you could state, r, R and the arm length then I could understand the ratios. Thanks, Ted ----- Original Message ----- From: "Randall Peters" To: Sent: Sunday, December 20, 2009 6:44 AM Subject: compound vertical seismometer Ted, The vertical seismometer that I showed at the broadband conference in 2004 http://www.iris.edu/stations/seisWorkshop04/seisWorkshop.htm, which you referenced by http://www.iris.washington.edu/stations/seisWorkshop04/PDF/CompoundVerticalSeismometer.pdf operates on the principle of the archer's compound bow. I published a paper in 2000 concerned with the physics of the compound bow, titled "Archer's compound bow, smart use of nonlinearity". It is online at http://physics.mercer.edu/petepag/combow.html. Because of force reduction at full draw, due to the eccentrics (cams), the bow concept can be used to lengthen the period of a similarly operating seismometer. John Nelson asked about this possibility in a mailing to the listserve in 2003, to which Chris Chapman responded http://www.seismicnet.com/psnlist/030502_055148_1.html For additional pictures of the prototype that I built, you may go to my webpage at http://physics.mercer.edu/petepag/cvs.html The sensor employed in this prototype is one of my fully-differential capacitive forms, but other types (such as coil/magnet) could be used. As Chris has frequently pointed out, if you were to use the Faraday law sensor, it is important that the coil (not the magnet) be the moving part. I never had time to pursue this concept the way I wanted to, but the data that was presented at the IRIS-sponsored conference (first reference above) shows that it has promise--especially if you were to build one a lot bigger. I wanted to try this with an elastic element using carbon epoxy elements in some arrangement, but never got around to it. Incidently, the first one of these ever built was by one of my students when I was at Texas Tech University, around 1997. It was much larger and used a coil spring (approximately LaCoste zero-length type) instead of the torsion wires of the prototype, but I never got around to seriously using it, since I moved to Mercer University soon thereafter. You may be interested to know that Erhard Wielandt, who was at the conference, encouraged me to try and get amateur seismologists interested in using the ideas. A number of the folks there were very curious about the instrument, since it had been setup on a table and made quasi-functional. Randall__________________________________________________________ Public Seismic Network Mailing List (PSN-L) __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: microseisms--especially to those with radio experience From: Randall Peters PETERS_RD@.......... Date: Sun, 20 Dec 2009 09:59:05 -0500 I am satisfied that there is much more to learn about microseisms than is b= elieved by those who swear by conventional wisdom. I got my start in physi= cs as an amateur radio (ham) operator. Unfortunately, I failed to renew my= general class license years ago (k4ovo). The radio experience has served = me well, along with some other physics faculty members that I know. For ex= ample, it has caused me to consider the following, which I hope some of you= will consider. The free-oscillations (eigenmodes) of the Earth, in which = it rings like a bell-- are at frequencies too low to be easily studied by d= irect means with the instruments which most of us use (not having supercond= ucting gravimeters). But I believe there may be a very simple way to study= the eigenmodes, using an idea that is basic to radio nearly a century old.= Just as intermediate frequencies based on heterodyning are a hallmark of = radio technology, I have reason to believe (because of nonlinearity) that t= he eigenmodes modulate the microseisms. When you look at the typical micro= seism spectrum, it looks like a broad continuous spectrum. But it really c= omprises a large number of fairly short-lived, well defined spectral lines.= The difference frequency between adjacent spectral lines appears in nearl= y every case to correspond to one of the eigenmode frequencies. The way to= see this is as follows--Using WinQuake, filter with a virtually zero bandp= ass that is centered on the peak of the microseisems. I have done this by = setting both high-pass and low-pass at the same value, such as 0.154 Hz, an= d select 10-poles for the filter characteristic of each. After doing this = filter, select 2000-s long individual segments for the x-scale, and then do= the FFT for each of these segments. If under options you select 'arrange'= , you can look simultaneously at both the time record and the spectrum for = a given segment. You will notice that the coherence time of individual mic= ro's is about 10 to 20 cycles. As you scan from start to end of a full day= 's record (I use one sample per second for these studies) you will see that= the spectrum is a set of sharp spectral lines with small separation freque= ncies between adjacent lines. The spacing between these lines changes as y= ou go from start to finish. I believe these differences comprise a finite = set of 'modulation' frequencies that are the Earth's eigenmode set. Is any= body interested in checking my hypothesis? It will take a bit of your time= to identify from the spectral lines thus displayed, enough cases to build = confidence in my claim.= __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: something else about microseisms From: Randall Peters PETERS_RD@.......... Date: Sun, 20 Dec 2009 10:15:12 -0500 For those of you who have both a vertical as well as a horizontal seismogra= ph, I would like for you to consider the following. Conventional wisdom says the microseisms are fundamentally of Rayleigh-= wave type. If they are generated by ocean pressure waves as is thought by = most (including myself because I have seen them increase dramatically durin= g hurricanes) then I don't believe they are Rayleigh waves. The reason has= to do with the mechanism of their generation by this means. Water cannot = support shear, as is well known; so what gets propagated away from the ocea= n bottom where the pressure is fluctuating--must be a vertically polarized = wave that I think of as a 'guided' wave in the crust of the earth. Because= of the granular nature of the crust, rotation effects cause the vertically= polarized vibration to take on horizontal components of accceleration. Th= us the waves begin to masquerade as Rayleigh waves. My first occasion to t= hink about this was when I moved my VolksMeter from a building basement sla= b to a pier that extends 20 feet down into the ground. Surprisingly, I fou= nd a dramatic difference in micro-signal for these two cases. The slab cas= e showed micro's nearly all the time, whereas the pier-case showed them onl= y occasionally and smaller when present. So what physics-experience is the= basis for my belief? My PhD was concerned with the propagation of ultraso= und (acoustic) waves in solids. The waves were introduced to the samples u= sing an x-cut quartz crystal. Anybody who has done such work knows that bo= nds to couple transducer and sample are crucial to the success of the work.= They also know that you can't transmit shear waves through a liquid. Thi= s is in fact the reason we know (from seismic studies) that the earth's cor= e includes a liquified one that surrounds the innermost solid one. I am su= rprised by the fact that this property of liquids is apparently thus well k= nown to seismologists, while at the same time they believe that water (pres= sure) waves working on the floor of the ocean could generate horizontal mot= ions of that floor as well as vertical ones. = __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: something else about microseisms From: Robert McClure bobmcclure90@......... Date: Sun, 20 Dec 2009 20:53:15 -0500 The Rayleigh wave is a surface wave mode having retrograde elliptical particle motion. When you push up and down on a particular spot on the elastic earth, there must be a resulting longitudinal motion away from the depressed area. Vertical force is enough to drive the wave. You do not need to supply any transverse force. Bob Dr. Peters said "This is in fact the reason we know (from seismic studies) that the earth's core includes a liquified one that surrounds the innermost solid one. I am surprised by the fact that this property of liquids is apparently thus well known to seismologists, while at the same time they believe that water (pressure) waves working on the floor of the ocean could generate horizontal motions of that floor as well as vertical ones." __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Rayleigh waves From: Randall Peters PETERS_RD@.......... Date: Mon, 21 Dec 2009 08:52:51 -0500 Bob, I agree with you that the vertical strain will give rise to a transver= se strain also, because of the Poisson ratio. However, I don't see in this= a mechanism for the required phase difference between the two components. = In a Rayleigh wave the vertical and horizontal motions are out of phase wi= th each other by 90 degrees--what is called phase quadrature. If what you = say is true, then why are there no significant Rayleigh components associat= ed directly with the vertical component of an earthquake rupture? In other= words I would expect two surface waves following arrivals of P and S--one = from the rupture itself and the other from the superposition of P and S, as= described in all seismology textooks. (The textbook argument for their gen= eration is one of P and S waves combining at the surface after they have tr= aveled a distance that is a significant fraction of the radius of the Earth= ). This description involving superposition is one that I fully appreciate= from a conceptual point of view. The physics ought to be the same whethe= r for teleseismic surface waves of Rayleigh type and for solid state filter= s called surface acoustic wave (SAW) devices. The saw devices use interlea= ved electrodes that operate on the basis of the force that exists between a= djacent strips because of their capacitance. Moreover, they are a coherent= array, meaning enough strips to provide several wavelengths. I believe th= e force between strips must involve both vertical and horizontal components= ; i.e., a source of shear. I must admit that my description is one based o= n intuition that could be erroneous. The full description of math-type wou= ld be complicated and one with which the venerable A.E. H. Love would be pl= eased There is still another feature of fundamental physics that I believe= should be considered in relation to the microseisms, no matter whether my = hypothesis is true. The crust of the Earth has some very special propertie= s when it comes to geoscience. The Moho (crustal thickness) was discovered= as the result of the discontinuity in phase velocity of P-waves as they cr= oss the interface between crust and mantle. Thus I expect that microseisms= should be confined to the crust, behaving in a manner similar to electroma= gnetic guided waves. Since the crust as a waveguide cannot support waves w= hose wavelength is greater than the crustal thickness, this results in a lo= w frequency cutoff. In other words, the longest period limit should be est= ablished (assuming crust average thickness of 15 km) at about 6 s, assuming= P-wave velocity of 3 km/s. Is it just a coincidence that micro's with a p= eriod longer than 15 s are not (to my knowledge) observed? =20 Randall __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: WinSDR screen calibration From: Brett Nordgren brett3nt@............. Date: Mon, 21 Dec 2009 09:38:48 -0500 Hi all, I had recently been working with calculating the per-line scale factor for some GIF's being produced by WinSDR, so I took the opportunity to try to characterize how that generally relates to the number of lines displayed and the Y scale factor setting. So far what I have observed seems to suggest: Given that n is the number of lines displayed Y is the WinSDR Y scale factor For my screen (and possibly for any screen), D/A counts per line = 913 / (n+1) * Y So for a 24 hour - 24 line screen with Y = 2: counts per line = 913 / 25 * 2 = 73.04 If you are using a 16-bit, +-10V D/A you can go on to calculate: Volts per line = 73.04 counts/line / 3276.8 counts/Volt = 0.0223 The constant 3276.8 is 32,768 counts / 10 V, the maximum values for a 16-bit +-10V D/A And finally, from that, if you know your instrument's Volts / unit of ground motion, you can divide by that number to get the ground motion represented by each line. This seems to hold true for both the screen displays as well as for GIF file creation. Larry, I'd be interested in whether this seems to make sense to you, and have I missed anything? Regards, Brett Watch our wiggles http://bnordgren.org/seismo/gif_images.htm or watch some very very good wiggles http://aslwww.cr.usgs.gov/Seismic_Data/telemetry_data/ANMO_24hr.html __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Rayleigh waves From: chrisatupw@....... Date: Mon, 21 Dec 2009 13:45:57 EST In a message dated 21/12/2009, PETERS_RD@.......... writes: Thus I expect that microseisms should be confined to the crust, behaving in a manner similar to electromagnetic guided waves. Since the crust as a waveguide cannot support waves whose wavelength is greater than the crustal thickness, this results in a low frequency cutoff. In other words, the longest period limit should be established (assuming crust average thickness of 15 km) at about 6 s, assuming P-wave velocity of 3 km/s. Is it just a coincidence that micro's with a period longer than 15 s are not (to my knowledge) observed? Hi Randall, We not infrequently see microseisms with periods of 10 to 12 seconds in the UK, when there are storms in the north Atlantic, as well as the normal ones at about one half this period, 5 to 7 seconds. Is the 6 sec microseism period not determined by the period of the deep ocean waves? Or are we considering on shore waves, which seem to be different? How do the other component amplitudes measured on the 20 ft pier and on the surface plinth compare? The P, S and Love waves? The USGS time travel graph assumes about 3.7 km / sec for Rayleigh waves. Have the microseism velocities been measured separately, please? Wide variations seem to have been reported in the past. Do you have a reference for the comparison of microseism amplitudes detected at the surface and in a borehole, please? Regards, Chris
In a message dated 21/12/2009, PETERS_RD@.......... writes:
Thus I=20 expect that microseisms should be confined to the crust, behaving in a= manner=20 similar to electromagnetic guided waves.  Since the crust as a wave= guide=20 cannot support waves whose wavelength is greater than the crustal thickn= ess,=20 this results in a low frequency cutoff.  In other words, the longes= t=20 period limit should be established (assuming crust average thickness of= 15 km)=20 at about 6 s, assuming P-wave velocity of 3 km/s.  Is it just a=20 coincidence that micro's with a period longer than 15 s are not (to my= =20 knowledge) observed? 
Hi Randall,
 
    We not infrequently see microseisms with peri= ods of=20 10 to 12 seconds in the UK, when there are storms in the north Atlant= ic, as=20 well as the normal ones at about one half this period, 5 to 7=20 seconds.
 
    Is the 6 sec microseism period not determined= by=20 the period of the deep ocean waves? Or are we considering on shore waves,= which=20 seem to be different?
 
    How do the other component amplitudes measure= d on=20 the 20 ft pier and on the surface plinth compare? The P, S and Love waves?= The=20 USGS time travel graph assumes about 3.7 km / sec for Rayleigh waves.
    Have the microseism velocities been measured= =20 separately, please? Wide variations seem to have been reported in the=20 past.
 
    Do you have a reference for the comparis= on of=20 microseism amplitudes detected at the surface and in a borehole, please?
    
    Regards,
 
    Chris
Subject: Re: compound vertical seismometer From: "Geoffrey" gmvoeth@........... Date: Mon, 21 Dec 2009 18:48:03 -0700 A note on the complexity of your verbosity; For us laymen (namely me) it would be nice if you talked in terms of reducing the effects of gravity to lengthen the free period of any system. most of you seem to me to be pros instead of amatures because your language suggests your education level on par with engineers. Are any of you able to "Talk Down" like the military instructors are taught to do to the troops working on things who lack a university education. You do not need to label things according to their inventors just mention them at the end of whatever you say. But like a pendulum where P = 2Pi*SQR(l/g) l = (P/2Pi)^2*g just tell us how your device is lowering the g factor to get a period of 5 or more seconds free period. Springs are behaving very similar to a pendulum they pretty much obey this formula too. g is like 9.80665 meters/sec^2 or 9.80665E003/25.4 inches per second squared you must whatever you are doing be lowering the g factor to increase your periods. Using this as your reference could greatly simplify all the technical jargon you guys are using. Show us an exploded diagram along with the details of every part and leave out the hard to understand jargon for those who lack the education. Tell us how you are lowering the g constant factor. A photo is very good but does not tell the story like an exploded diagram with parts list explaining each and every part. Dont laugh at this idea, but, its a classic case of anti-gravity. :-) There is nothing like a set of blueprints or formal mechanical drawings to build something by. Amatures are lacking technical standards for building (cheaply) things (seismometers) that give uniform results whoever builds whatever. It seems the pros do not want the amatures to understand their designs for fear of loosing money at the industrial level of building things. It is my great hope to see a velocity or displacement vertical with a free period between 10 seconds and 5 seconds that I can build myself for under $200, one I can bury in the ground without having to dig a big hole like the mammoth cave in Virginia. My aging back can not do that anymore. Just a note of hopefulness for meaningful simplification of whatever; geoff ----- Original Message ----- From: "Randall Peters" To: Sent: Sunday, December 20, 2009 6:44 AM Subject: compound vertical seismometer Ted, The vertical seismometer that I showed at the broadband conference in 2004 http://www.iris.edu/stations/seisWorkshop04/seisWorkshop.htm, which you referenced by http://www.iris.washington.edu/stations/seisWorkshop04/PDF/CompoundVerticalSeismometer.pdf operates on the principle of the archer's compound bow. I published a paper in 2000 concerned with the physics of the compound bow, titled "Archer's compound bow, smart use of nonlinearity". It is online at http://physics.mercer.edu/petepag/combow.html. Because of force reduction at full draw, due to the eccentrics (cams), the bow concept can be used to lengthen the period of a similarly operating seismometer. John Nelson asked about this possibility in a mailing to the listserve in 2003, to which Chris Chapman responded http://www.seismicnet.com/psnlist/030502_055148_1.html For additional pictures of the prototype that I built, you may go to my webpage at http://physics.mercer.edu/petepag/cvs.html The sensor employed in this prototype is one of my fully-differential capacitive forms, but other types (such as coil/magnet) could be used. As Chris has frequently pointed out, if you were to use the Faraday law sensor, it is important that the coil (not the magnet) be the moving part. I never had time to pursue this concept the way I wanted to, but the data that was presented at the IRIS-sponsored conference (first reference above) shows that it has promise--especially if you were to build one a lot bigger. I wanted to try this with an elastic element using carbon epoxy elements in some arrangement, but never got around to it. Incidently, the first one of these ever built was by one of my students when I was at Texas Tech University, around 1997. It was much larger and used a coil spring (approximately LaCoste zero-length type) instead of the torsion wires of the prototype, but I never got around to seriously using it, since I moved to Mercer University soon thereafter. You may be interested to know that Erhard Wielandt, who was at the conference, encouraged me to try and get amateur seismologists interested in using the ideas. A number of the folks there were very curious about the instrument, since it had been setup on a table and made quasi-functional. Randall__________________________________________________________ Public Seismic Network Mailing List (PSN-L) __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: WinSDR screen calibration From: Larry Cochrane lcochrane@.............. Date: Mon, 21 Dec 2009 18:29:16 -0800 Hi Brett, I think you mean A/D not D/A, WinSDR does not deal with D/A converters. Also, I think you mean X-Scale not Y-Scale. The Y-Scale controls the signal level (up/down motion) in the real-time window or GIF image and the X-Scale controls the time. The number of lines per channel and the time period per line has nothing to do with the Y-Scale. If you mean the X-Scale, the X-Scale is in minutes per line. Regards, Larry Cochrane Redwood City, PSN Brett Nordgren wrote: > Hi all, > > I had recently been working with calculating the per-line scale factor for > some GIF's > being produced by WinSDR, so I took the opportunity to try to characterize > how that > generally relates to the number of lines displayed and the Y scale factor > setting. > > So far what I have observed seems to suggest: > > Given that > n is the number of lines displayed > Y is the WinSDR Y scale factor > > For my screen (and possibly for any screen), > D/A counts per line = 913 / (n+1) * Y > So for a 24 hour - 24 line screen with Y = 2: > counts per line = 913 / 25 * 2 = 73.04 > > If you are using a 16-bit, +-10V D/A you can go on to calculate: > > Volts per line = 73.04 counts/line / 3276.8 counts/Volt = 0.0223 > > The constant 3276.8 is 32,768 counts / 10 V, the maximum values > for a 16-bit +-10V D/A > > And finally, from that, if you know your instrument's Volts / unit of > ground motion, > you can divide by that number to get the ground motion represented by each > line. > > This seems to hold true for both the screen displays as well as for GIF > file creation. > > Larry, I'd be interested in whether this seems to make sense to you, and have > I missed anything? > > Regards, > Brett > > Watch our wiggles > http://bnordgren.org/seismo/gif_images.htm > > or watch some very very good wiggles > http://aslwww.cr.usgs.gov/Seismic_Data/telemetry_data/ANMO_24hr.html > > > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: WinSDR screen calibration From: Brett Nordgren brett3nt@............. Date: Mon, 21 Dec 2009 22:06:22 -0500 Hi Larry, You are absolutely right, I meant A/D digitizer. However I was indeed referring to the Y-scale sensitivity, as measured between successive horizontal lines. Rarely are helicorder displays labeled to indicate their sensitivity, and even when they are it usually is hard for me to figure out what is meant by the label. Working from the calibrated instrument sensitivity, I wanted to be able to say something like, "Each horizontal line represents a velocity of 1um/second". So, for example, a waveform peak six lines high would represent a peak ground velocity of 6um/sec. Regards, Brett At 06:29 PM 12/21/2009 -0800, you wrote: >Hi Brett, > >I think you mean A/D not D/A, WinSDR does not deal with D/A converters. >Also, I think >you mean X-Scale not Y-Scale. The Y-Scale controls the signal level >(up/down motion) >in the real-time window or GIF image and the X-Scale controls the time. >The number of >lines per channel and the time period per line has nothing to do with the >Y-Scale. If >you mean the X-Scale, the X-Scale is in minutes per line. > >Regards, >Larry Cochrane >Redwood City, PSN > >Brett Nordgren wrote: >>Hi all, >>I had recently been working with calculating the per-line scale factor >>for some GIF's >>being produced by WinSDR, so I took the opportunity to try to >>characterize how that >>generally relates to the number of lines displayed and the Y scale factor >>setting. >>So far what I have observed seems to suggest: >>Given that >>n is the number of lines displayed >>Y is the WinSDR Y scale factor >>For my screen (and possibly for any screen), >>D/A counts per line = 913 / (n+1) * Y >>So for a 24 hour - 24 line screen with Y = 2: >>counts per line = 913 / 25 * 2 = 73.04 >>If you are using a 16-bit, +-10V D/A you can go on to calculate: >>Volts per line = 73.04 counts/line / 3276.8 counts/Volt = 0.0223 >>The constant 3276.8 is 32,768 counts / 10 V, the maximum values >>for a 16-bit +-10V D/A >>And finally, from that, if you know your instrument's Volts / unit of >>ground motion, >>you can divide by that number to get the ground motion represented by >>each line. >>This seems to hold true for both the screen displays as well as for GIF >>file creation. >>Larry, I'd be interested in whether this seems to make sense to you, and have >>I missed anything? >>Regards, >>Brett > >Watch our wiggles >http://bnordgren.org/seismo/gif_images.htm > >or watch some very very good wiggles >http://aslwww.cr.usgs.gov/Seismic_Data/telemetry_data/ANMO_24hr.html __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Rayleigh Waves From: Robert McClure bobmcclure90@......... Date: Mon, 21 Dec 2009 23:37:01 -0500 It helps to visualize the various seismic waves that propagate in the body and on the surface of the earth. To this end, I refer you to web site http://www.daleh.id.au/seismic_theory.html. There, you will find instructive animations of P, S, Love, and Rayleigh waves. These animations are borrowed from Lawrence W. Braile, Professor, Department of Earth and AtmosphericSciences, Purdue University, West Lafayette, Indiana. No doubt they appear on his website as well. http://web.ics.purdue.edu/~braile/ You will see that the particle motions of the surface waves (Love and Rayleigh, do indeed decrease with depth. The shorter the period the greater the rate of attenuation. Borehole seismometers take advantage of this decrease with depth to reduce the sensed amplitude of microseisms and cultural noise. Bob __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Vertical vs. Horz. From: "Ted Channel" tchannel@............ Date: Tue, 22 Dec 2009 07:13:33 -0700 Merry Christmas Folks, I hope you all enjoy holidays. I may have asked this question before, but need to ask it again. I have recorded more earthquakes on vertical sensors then horizontal = sensors. Several different approaches for both, and a variety of = periods, from 1 to 25 seconds. My next sensor will be a vertical. Before I begin I wanted to ask the = following. I know the 1.5 second vertical, will see the P and if the event is = large enough, it will see other phases.=20 Picture a free hanging spring with a mass. My theory is the P wave stimulates the spring from an angle, a bit like = its coming from your feet to your head. An example would be if the earthquake occurred 180 degrees from the = sensor, the result would be directly from your feet to your head. =20 1 I know this is an over simplification, but does the P arrives at an = angle (bottom to top) and this influences the spring? Yes, I have seen = different explanations, wave simulator etc. but these did not answer the = question. If this is not the case can someone explain how the vertical = spring is influenced. The obvious advantage of a vertical is they see many earthquakes, the = disavantage they are limited and also see a lot of other things which = are not earthquakes. All of my verticals have been 1 to 2.5 seconds. = This range has never seemed to be and advantage or disadvantage. The = 2.5 second seemed to work no better then the 1 second. I think this = is because the sensor is just picking up the P (mainly) anyhow. However on a big event it does show the P, the S and some other phases. = A typical vertical sensor recording will have a trace of 20 mins vs. a = 3 hours trace on the Lehman. 2. If I could achieve a long period vertical, what would be the ideal = target, if there is one? An example the period target for a Lehman = style is 20 seconds. Before I being, I wanted to understand, if the longer period (vertical) = would be any benefited. I know I could create a vertical with 3 = seconds. I don't know if I could create one with 6 seconds. If there = is no advantage to the longer period in the Z axis, then it would serve = no purpose. One's location has an influence on which sensor type works for them. = I enjoy having both vertical and horz, shorter and longer periods. In = this case, I want to target a longer period vertical if the longer = period would be better. Thanks, Ted
Merry Christmas Folks,   I = hope you all=20 enjoy holidays.
 
I may have asked this question before, = but need to=20 ask it again.
 
I have recorded more earthquakes on = vertical=20 sensors then horizontal sensors.    Several different = approaches=20 for both, and a variety of periods, from 1 to 25 seconds.
My next sensor will be a = vertical.  =20 Before I begin I wanted to ask the following.
 
I know the 1.5 second = vertical, will=20 see the P and if the event is  large enough, it will=20 see other phases. 
Picture a free hanging spring with a=20 mass.
My theory is the P wave stimulates the = spring from=20 an angle, a bit like its coming from your feet to your = head.
An example would be if the earthquake = occurred 180=20 degrees from the sensor, the result would be directly from your feet to = your=20 head.   
 
1  I know this is an over = simplification,=20 but does the  P arrives at an angle (bottom to top) and this=20 influences the spring?   Yes, I have seen different = explanations, wave=20 simulator etc. but these did not answer the question.   = If this=20 is not the case can someone explain how the vertical spring is=20 influenced.
 
 
The obvious advantage of a vertical is = they see=20 many earthquakes, the disavantage they are limited and also see a lot of = other=20 things which are not earthquakes.    All of my verticals = have=20 been 1 to 2.5 seconds.  This range has never seemed to be and = advantage or=20 disadvantage.   The 2.5 second seemed to work no better then = the 1=20 second.    I think this is because the sensor is just = picking up=20 the P (mainly) anyhow.
However on a big event it does show the = P, the S=20 and some other phases.   A typical vertical sensor = recording will=20 have a trace of  20 mins vs. a 3 hours trace on the = Lehman.
 
2.  If I could achieve a long = period vertical,=20 what would be the ideal target, if there is one?   An example = the=20 period target for a Lehman style is 20 seconds.
 
Before I being, I wanted to understand, = if the=20 longer period (vertical) would be any benefited.    I = know I=20 could create a vertical with 3 seconds.   I don't know if I = could=20 create one with 6 seconds.   If there is no advantage to the = longer=20 period in the Z axis, then it would serve no purpose.
 
One's location has an influence on = which sensor=20 type works for them.    I enjoy having both vertical and = horz,=20 shorter and longer periods.   In this case, I want to target a = longer=20 period vertical if the longer period would be better.
 
Thanks, Ted
Subject: Re: Rayleigh Waves From: Bob Hancock icarus@......... Date: Tue, 22 Dec 2009 08:12:10 -0700 Bob McClure is absolutely correct about visualization of the Rayleigh = wave. The particle motion for the Rayleigh wave was difficult for me to = grasp until I hand plotted the data through several phase differences. = After making the plots I was able to visualize the particle motion of = the Rayleigh wave. I used the following instructions found in the SAC = manual for particle motion plots: "...In a particle-motion plot one evenly spaced file is plotted = against another. For each value of the independent variable, normally time, the = value of the dependent variable of the first file is plotted along the y axis = and the value of the dependent variable of the second file is plotted along = the x axis. For a pair of seismograms this type of plot shows the motion of a "particle" in the plane of the two seismograms as a function of time. A square plot is generated, with the limits along each axis being = the minimum and maximum values of the dependent variable...." As previously pointed out the Rayleigh wave is made up of two separate = motions. There is a radial wave and a vertical wave. To achieve the = optimum retrograde circular motion, the radial wave (similar to a P = wave) precedes the vertical wave motion by 1/4 of the wavelength. It = was particularly interesting to vary the phase difference and amplitude = of each wave component, and note the changes in the shape of the = Rayleigh wave particle motion. I did this at 1/8 wave length intervals = from a -1 to a + 1 phase differential to better understand this motion. Particle motion can be viewed either by hand plotting or by rotating the = data in the two horizontal channels. When rotated two additional files = are generated which are called the Radial and Transverse channels. = Following is a simple explanation of the process of rotation from Prof. = George Zandt, University of Arizona: "...Rotation, or more precisely, rotation of seismograms from the ZNE = coordinates to ZRT coordinates is relatively straightforward. The choice = of recording the NS and EW components of ground motion is rather = arbitrary, right? You just need to record two orthogonal (at rt angles) = directions, could be NE and SE, but by convention sesimologists always = use N and E. If your events are coming from N or S or E or W, then the = data is called "naturally rotated" and you can clearly see the = separation of Love and Rayleigh, for example. But for any other = direction, its not naturally rotated. So, you can rotate the data = yourself to the radial and transverse directions. Mathematically, this = is quite simple and involves multiplying the data by cosine of the = difference in angles...." I am unaware of any programs that run on Windows that will perform the = functions of rotation and particle motion as applied to seismograms, in = particular PSN4 format data. Bob Hancock Three Points, AZ On Dec 21, 2009, at 9:37 PM, Robert McClure wrote: > It helps to visualize the various seismic waves that propagate in > the body and on the surface of the earth. To this end, I refer you to > web site >=20 > http://www.daleh.id.au/seismic_theory.html. >=20 > There, you will find instructive animations of P, S, Love, and > Rayleigh waves. These animations are borrowed from Lawrence W. Braile, > Professor, Department of Earth and AtmosphericSciences, Purdue > University, West Lafayette, Indiana. No doubt they appear on his > website as well. >=20 > http://web.ics.purdue.edu/~braile/ >=20 > You will see that the particle motions of the surface waves (Love > and Rayleigh, do indeed decrease with depth. The shorter the period > the greater the rate of attenuation. Borehole seismometers take > advantage of this decrease with depth to reduce the sensed amplitude > of microseisms and cultural noise. >=20 > Bob > __________________________________________________________ >=20 > Public Seismic Network Mailing List (PSN-L) >=20 > To leave this list email PSN-L-REQUEST@.............. with=20 > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. >=20 __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Rayleigh waves From: Randall Peters PETERS_RD@.......... Date: Tue, 22 Dec 2009 11:31:43 -0500 Bob, Your comment concerning boreholes is interesting for the following rea= son. Prof. Dan Russell at Kettering Univ. has one of the best wave simulat= ion programs I've seen. It is online at http://paws.kettering.edu/~drussell/Demos/waves/wavemotion.html If you look at his Rayleigh simulation, note also his comment that the c= ounterclockwise circulation goes over into clockwise at a depth of about on= e-fifth of a wavelength. For wave speed of 3000 m/s and a period of 3 s, t= his should happen at a depth of 1500 m. Since my cylinder (on which the p= ier rests) goes down only about 6 m maximum, it should therefore be moving = almost completely (top to bottom) in accord with the surface clockwise moti= on. One would have to use a very deep borehole indeed, for the influence = of depth to eliminate the microseisms by means of inherent attenuation, ass= uming that microseisms are pure Rayleigh waves. Randall

Bob,

     Your comment concerning boreh= oles is interesting for the following reason.  Prof. Dan Russell at Ketteri= ng Univ. has one of the best wave simulation programs I’ve seen. It is online at

ht= tp://paws.kettering.edu/~drussell/Demos/waves/wavemotion.html

   If you look at his Rayleigh simulation, n= ote also his comment that the counterclockwise circulation goes over into clock= wise at a depth of about one-fifth of a wavelength.  For wave speed of 3000= m/s and a period of 3 s, this should happen at a depth of 1500 m.  Since m= y  cylinder (on which the pier rests) goes down only about 6 m maximum, it should there= fore be moving almost completely (top to bottom) in accord with the surface clockwise motion.   One would have to use a very deep borehole in= deed, for the influence of depth to eliminate the microseisms by means of inheren= t attenuation, assuming that microseisms are pure Rayleigh waves. 

   Randall

Subject: correction for surface rotation of my pier From: Randall Peters PETERS_RD@.......... Date: Tue, 22 Dec 2009 11:35:30 -0500 I said clockwise, but meant to say counterclockwise for the surface motion,= in accord with Russell's animation.

I said clockwise, but meant to say counterclockwise fo= r the surface motion, in accord with Russell’s animation.

Subject: Chris Chapmans article on EMSC newsletter From: meredith lamb paleoartifact@......... Date: Tue, 22 Dec 2009 09:58:48 -0700 Hi all, Chris Chapman has written a article on page 19 of the European-Mediterranean Seismological Center; newsletter where it pertains to the SEP UK seismometer. The issue also is predominated with other representative countrys school articles in that area. The below URL is a 42MB PDF version. http://www.emsc-csem.org/docs/data/newsletters/newsletter_24_low.pdf There is also a higher 66MB resolution of the same: http://www.emsc-csem.org/docs/data/newsletters/newsletter_24.pdf The reader of such, would need a high speed and/or broadband internet connection. The "home" URL is at: http://emsc-csem.org/index.php?page=home While the current manufactured SEP version is shown in photographs on page 12 and 18, Chris's more recent prototype photograph on page 19 would appear to be much more stable and offers a yet longer operational period per his past trials and email notes. Best of all; the newer prototype is vastly easier to home workshop reproduce than the SEP. Without reserve; I think the "Chapman" is the best student/amateur oriented horizontal instrument design innovation since the "Lehman". Best holiday wishes to all, Meredith Lamb Hi all,

Chris Chapman has written a article on page 19 of the Europe= an-Mediterranean Seismological Center; newsletter
where it pertains to t= he SEP UK seismometer.=A0 The issue also is predominated with other represe= ntative
countrys school articles in that area. The below URL is a 42MB PDF version.=

http://www.emsc-csem.org/docs/data/newslett= ers/newsletter_24_low.pdf

There is also a higher 66MB resolution of the same:

http://www.emsc-csem.org/docs/data/newsletters/newsletter_24.pdf

The reader of such, would need a high speed and/or broadband internet c= onnection.

The "home" URL is at:

http://emsc-csem.org= /index.php?page=3Dhome


While the current manufactured SEP version is shown in photographs on p= age 12 and 18, Chris's more
recent prototype photograph on page 19 w= ould appear to be much more stable and offers a yet longer
operational p= eriod per his past trials and email notes.=A0 Best of all; the newer protot= ype is vastly easier
to home workshop reproduce than the SEP.=A0 Without reserve; I think the &q= uot;Chapman" is the best
student/amateur oriented horizontal instru= ment design innovation since the "Lehman".=A0 =A0

Best ho= liday wishes to all,

Meredith Lamb

=A0
Subject: Microseism modulation From: Chuck/Judy Burch cjburch@........... Date: Tue, 22 Dec 2009 13:18:11 -0700 Randall, Could you further explain your procedure for detecting modulation of microseisms by free mode energy? What specifically are you doing with the narrow bandpass filter? Thanks, Chuck Burch __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: the matter of possible modulation From: Randall Peters PETERS_RD@.......... Date: Tue, 22 Dec 2009 16:20:39 -0500 Chuck, First do a high pass filter on your data with a corner frequency of say= 0.005 Hz, to remove the secular trend in the record and eliminate the prob= lem of Gibb effect. Then take the FFT of the complete one-day record and l= ook to see if there is a microseismic hump in the spectrum. Note the frequ= ency of the maximum in that hump and use its value to again do filtering, b= ut this time both a high and a low pass at the same value, corresponding to= a bandpass filter at the hump frequency. Then open the filtered signal wi= th an x-scale of say 2000 s. After doing this you will see that the micro'= s 'come and go' according to what is called their correlation time, typical= ly no more than 10 or twenty cycles. For the hump having a period of 3 s (= 0.33 Hz), this means a given micro-signal persists for no more than about 3= 0 s before dying out, only to be followed by another short lived signal. T= hese approximately 30 s pieces comprise individually a set of very sharp sp= ectral lines, separated from one another (closest neighbors) by what appear= s to be values of the eigenmode frequencies, in mHz. To see these individu= al lines use the WinQuake FFT that is the rightmost one of the pair in Larr= y's code. They will be most vivid if displayed in linear rather than log s= cale. If you place the cursor on a given line you can read its frequency a= nd then move on to an adjacent line, left or right; read it and then write = down the difference value between them. I am especially interested in seei= ng how many of these difference frequency values comprise a distinct set of= values, as opposed to being randomly distributed group of numbers. If so,= then the free modes must be modulating the microseisms. The only way to k= now for sure is to collect enough delta-f values in the manner I've just de= scribed to generate a statistical base having reasonable confidence. I did= a cursory inspection of some of my records this way, and the results look = quite promising. Those of us familiar with heterodyne processes in radio s= hould not be surprised. The process of modulation involves a carrier that = is influenced by lower frequency signals by means of nonlinear processes. = In my thinking, the mircroseisms would be the carrier, and the eigenmodes b= e "what our planet is trying to tell us if we have the demodulation means i= n a receiver to hear what she is saying".=20 Randall= __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Microseism modulation From: =?ISO-8859-1?Q?J=F3n_Fr=EDmann?= jonfr@......... Date: Tue, 22 Dec 2009 21:36:10 +0000 Hello all, Micro-earthquakes have high frequancy but low energy. This is common for earthquakes that are from -2.0ML and up to 2.50ML in size. The best way to detect micro-earthquakes is with a seismomter that has main frequancy of 1Hz and up to 4,5Hz. The only expection from this appears to be if the earthquake is magma or volcano activited. Regards, J=F3n Fr=EDmann. On =FEri, 2009-12-22 at 13:18 -0700, Chuck/Judy Burch wrote: > Randall, >=20 > Could you further explain your procedure for detecting modulation of=20 > microseisms by free mode energy? What specifically are you doing with=20 > the narrow bandpass filter? >=20 >=20 > Thanks, >=20 > Chuck Burch > __________________________________________________________ >=20 > Public Seismic Network Mailing List (PSN-L) >=20 > To leave this list email PSN-L-REQUEST@.............. with=20 > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Vertical vs. Horz. From: Brett Nordgren brett3nt@............. Date: Tue, 22 Dec 2009 17:34:20 -0500 Hi Ted, At 07:13 AM 12/22/2009 -0700, you wrote: >Merry Christmas Folks, I hope you all enjoy holidays. The same to you and to everyone on the list. > I may have asked this question before, but need to ask it again. > >I have recorded more earthquakes on vertical sensors then horizontal >sensors. Several different approaches for both, and a variety of >periods, from 1 to 25 seconds. >My next sensor will be a vertical. Before I begin I wanted to ask the >following. > >I know the 1.5 second vertical, will see the P and if the event is large >enough, it will see other phases. >Picture a free hanging spring with a mass. >My theory is the P wave stimulates the spring from an angle, a bit like >its coming from your feet to your head. >An example would be if the earthquake occurred 180 degrees from the >sensor, the result would be directly from your feet to your head. > >1 I know this is an over simplification, but does the P arrives at an >angle (bottom to top) and this influences the spring? Yes, I have seen >different explanations, wave simulator etc. but these did not answer the >question. If this is not the case can someone explain how the vertical >spring is influenced. What you suggest I believe is true, that P waves may have some vertical component, though there might possibly be another contribution related to something that Randall mentioned. We frequently see P waves on the verticals, sometimes quite strongly, which might in part relate to the fact that when something gets squeezed in one direction, it will expand somewhat to the sides. This ratio of the sideways expansion to the original amount of compression is called Poisson's Ratio, which for many materials is about 1/3. As an horizontal P wave expands and compresses the earth, it may possibly be causing additional vertical motion due to that effect, which you should see on the vertical (though I don't know what Poisson's ratio might be for dirt). Like most earth motion descriptions, it is probably a rather complex combination of those and some other effects. >The obvious advantage of a vertical is they see many earthquakes, the >disavantage they are limited and also see a lot of other things which are >not earthquakes. All of my verticals have been 1 to 2.5 seconds. This >range has never seemed to be and advantage or disadvantage. The 2.5 >second seemed to work no better then the 1 second. I think this is >because the sensor is just picking up the P (mainly) anyhow. >However on a big event it does show the P, the S and some other >phases. A typical vertical sensor recording will have a trace of 20 >mins vs. a 3 hours trace on the Lehman. > >2. If I could achieve a long period vertical, what would be the ideal >target, if there is one? An example the period target for a Lehman style >is 20 seconds. From what I have seen, much of the surface-wave energy of large teleseisms is in the region of 18 to 20 seconds, and sometimes longer. 20 seconds will see a lot, while 40 or 50 seconds can often see somewhat more. > Before I being, I wanted to understand, if the longer period (vertical) > would be any benefited. I know I could create a vertical with 3 > seconds. I don't know if I could create one with 6 seconds. If there > is no advantage to the longer period in the Z axis, then it would serve > no purpose. One problem is that there is so much microseism noise in the six-second region and also around 12 seconds. I generally use a 0.08Hz (12.5 second) 4 or 6 pole low pass filter to cut out most of that noise, while allowing through much of the big-quake frequencies. An instrument that can only go down to 6 seconds will unfortunately be quite good at displaying the noise while missing most teleseism surface waves. > One's location has an influence on which sensor type works for > them. I enjoy having both vertical and horz, shorter and longer > periods. In this case, I want to target a longer period vertical if the > longer period would be better. The only problem is that the movement of a seismometer in response to an error force, such as from small temperature changes, etc. increases as 1/Frequency^2 It is way harder to make a stable instrument for 50 seconds than for 10 or 20 or 6. Long period verticals almost certainly need to use a feedback design if they are going to be sensitive enough to see distant quakes while at the same time, insensitive enough to temperature and other variations to not wander off to maximum output. Regards, Brett Watch our wiggles http://bnordgren.org/seismo/gif_images.htm or watch some very very good wiggles http://aslwww.cr.usgs.gov/Seismic_Data/telemetry_data/ANMO_24hr.html __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Vertical vs. Horz. From: Robert McClure bobmcclure90@......... Date: Tue, 22 Dec 2009 18:02:33 -0500 Hi Ted, It is easy to get long period period response from a short period sensor. Just use my utility program, WQFilter.exe. It operates on PSN Type 4 files, and can extend the useful period by a factor of 8 or more. I operate medium period sensors, and I would be lost without this program. See my web site at http://sites.google.com/site/bobmcclure90/home for the program and explanatory pages. Be sure to follow my recommendations on the optimal use of WQFilter. Bob __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Vertical vs. Horz. From: "Ted Channel" tchannel@............ Date: Tue, 22 Dec 2009 16:54:28 -0700 Bob, I will download and try your WQFilter.exe Thanks for the advise. Ted ----- Original Message ----- From: "Robert McClure" To: "psn-l" Sent: Tuesday, December 22, 2009 4:02 PM Subject: Re: Vertical vs. Horz. > Hi Ted, > > It is easy to get long period period response from a short period > sensor. Just use my utility program, WQFilter.exe. It operates on PSN > Type 4 files, and can extend the useful period by a factor of 8 or > more. I operate medium period sensors, and I would be lost without > this program. See my web site at > > http://sites.google.com/site/bobmcclure90/home > > for the program and explanatory pages. Be sure to follow my > recommendations on the optimal use of WQFilter. > > Bob > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Vertical vs. Horz. From: ChrisAtUpw@....... Date: Tue, 22 Dec 2009 21:32:59 EST In a message dated 22/12/2009, brett3nt@............. writes: >1 I know this is an over simplification, but does the P arrives at an >angle (bottom to top) and this influences the spring? What you suggest I believe is true, that P waves may have some vertical component, though there might possibly be another contribution related to something that Randall mentioned. We frequently see P waves on the verticals, sometimes quite strongly, which might in part relate to the fact that when something gets squeezed in one direction, it will expand somewhat to the sides. Hi Brett, It may have even more to deal with the curved paths that the rays travel inside the spherical earth! This ratio of the sideways expansion to the original amount of compression is called Poisson's Ratio, which for many materials is about 1/3. As a horizontal P wave expands and compresses the earth, it may possibly be causing additional vertical motion due to that effect, which you should see on the vertical (though I don't know what Poisson's ratio might be for dirt). It is rock that you need to check. >The obvious advantage of a vertical is they see many earthquakes, the >disadvantage they are limited and also see a lot of other things which are >not earthquakes. All of my verticals have been 1 to 2.5 seconds. > A typical vertical sensor recording will have a trace of 20 >mins vs. a 3 hours trace on the Lehman. This must be an observational error. The noise on an uncased, uncompensated vertical may be over 20x that on a horizontal. The noise on verticals is only less at longer periods since atmospheric noise is excluded in contemporary seismometers by the hermetically sealed case. From what I have seen, much of the surface-wave energy of large teleseisms is in the region of 18 to 20 seconds, and sometimes longer. 20 seconds will see a lot, while 40 or 50 seconds can often see somewhat more. You definitely need the sensor response flat out to 20 seconds. A Lehman with this range will see 40 second waves at 1/4 their true amplitude. The roll-off in a vertical may be more rapid, depending on the type / feedback. One problem is that there is so much microseism noise in the six-second region and also around 12 seconds. I generally use a 0.08Hz (12.5 second) 4 or 6 pole low pass filter to cut out most of that noise, while allowing through much of the big-quake frequencies. An instrument that can only go down to 6 seconds will unfortunately be quite good at displaying the noise while missing most teleseism surface waves. Yup! I only see 10 second noise on a few days each month in the UK. The six second noise batters us all the time! > One's location has an influence on which sensor type works for them The only problem is that the movement of a seismometer in response to an error force, such as from small temperature changes, etc. increases as 1/Frequency^2 Even more critical are air density changes effecting a vertical sensor and also wind noise. Temperatures should change quite slowly inside an insulating case, assuming that the sun does not shine on it! It is way harder to make a stable instrument for 50 seconds than for 10 or 20 or 6. Long period verticals almost certainly need to use a feedback design if they are going to be sensitive enough to see distant quakes while at the same time, insensitive enough to temperature and other variations to not wander off to maximum output. Uh, Uh! Now define what you are calling long period? The Roberts' period compensating amplifier circuit is probably the easiest technique for amateurs to use. It has constant gain from the LP filter down to ~ the resonant frequency rf of the vertical sensor, at say 1/2 Hz. See _http://jclahr.com/science/psn/roberts/index.html_ (http://jclahr.com/science/psn/roberts/index.html) It was first used on geophones. Below this to about rf / 10, (= 1/20 Hz) the gain increases as 1 / f^2, so compensating the f^2 falling output to give a flat characteristic. So you can extend a 2 second period vertical sensor out to about 20 seconds quite easily. Extending the period much beyond x10 quickly runs into noise problems with a coil + magnet velocity detector. You need two of these stages with maximum gains of x10 (total x100 at 20 seconds) linked by a 2 pole high pass filter at ~ 1/30 Hz. Lennartz use a system like this. So do I and it works fine. Direct digital period compensation probably works best with 24 bit ADCs. The French use it on their schools system. 16 bit ADCs may only show a few counts (1/100 the rest of the signal) at x10 period, unless the gain is quite high and it may be partly masked by electronic noise. Regards, Chris Chapman
In a message dated 22/12/2009, brett3nt@............. writes:
>1  I know this is an over simplification, but does= =20 the  P arrives at an
>angle (bottom to top) and this influen= ces=20 the spring?  
What you suggest I believe is true, that P= waves=20 may have some vertical
component, though there might possibly be ano= ther=20 contribution related to
something that Randall mentioned.  We= =20 frequently see P waves on the
verticals, sometimes quite strongly,= which=20 might in part relate to the fact
that when something gets squeezed= in one=20 direction, it will expand somewhat
to the sides. 
Hi Brett,
 
    It may have even more to deal with the curved= paths=20 that the rays travel inside the spherical earth!
This=20 ratio of the sideways expansion to the original amount
of compressio= n is=20 called Poisson's Ratio, which for many materials is about
1/3. = As a=20 horizontal P wave expands and compresses the earth, it may
possibly= be=20 causing additional vertical motion due to that effect, which
you sho= uld=20 see on the vertical (though I don't know what Poisson's ratio
might= be for=20 dirt). 
    It is rock that you need to check.<= /DIV> >The=20 obvious advantage of a vertical is they see many earthquakes, the=20
>disadvantage they are limited and also see a lot of other things= which=20 are
>not earthquakes.  All of my verticals have been 1 to 2.= 5=20 seconds. 
> A typical vertical sensor recording will have a= trace=20 of  20
>mins vs. a 3 hours trace on the Lehman.
    This must be an observational error. The nois= e on=20 an uncased, uncompensated vertical may be over 20x that on a horizontal.= The=20 noise on verticals is only less at longer periods since atmospheric= noise=20 is excluded in contemporary seismometers by the hermetically sealed case.= =20    
From=20 what I have seen, much of the surface-wave energy of large teleseisms is=20 in the region of 18 to 20 seconds, and sometimes longer.  20 second= s=20
will see a lot, while 40 or 50 seconds can often see somewhat=20 more.
    You definitely need the sensor response = flat=20 out to 20 seconds. A Lehman with this range will see 40 second waves at 1/= 4=20 their true amplitude. The roll-off in a vertical may be more rapid, depend= ing on=20 the type / feedback.
One=20 problem is that there is so much microseism noise in the six-second
= region=20 and also around 12 seconds.  I generally use a 0.08Hz (12.5 second)=
4=20 or 6 pole low pass filter to cut out most of that noise, while allowing= =20
through much of the big-quake frequencies.  An instrument that= can=20 only go
down to 6 seconds will unfortunately be quite good at displa= ying=20 the noise
while missing most teleseism surface waves.
    Yup!   I only see 10 second noise&n= bsp;on=20 a few days each month in the UK. The six second noise batters us all the= =20 time!
>  One's location has an influence on which sensor= type=20 works for them

The only problem is that the movement of a seismom= eter=20 in response to an
error force, such as from small temperature change= s,=20 etc. increases as
1/Frequency^2   
    Even more critical are air density changes=20 effecting a vertical sensor and also wind noise. Temperatures should chang= e=20 quite slowly inside an insulating case, assuming that the sun does no= t=20 shine on it!
It is=20 way harder to make a stable instrument for 50
seconds than for 10 or= 20 or=20 6.  Long period verticals almost certainly
need to use a feedba= ck=20 design if they are going to be sensitive enough to
see distant quake= s=20 while at the same time, insensitive enough to
temperature and other= =20 variations to not wander off to maximum output.
    Uh, Uh! Now define what you are calling long= =20 period?
 
    The Roberts' period compensating amplifier ci= rcuit=20 is probably the easiest technique for amateurs to use. It has constant gai= n from=20 the LP filter down to ~ the resonant frequency rf of the vertical sen= sor,=20 at say 1/2 Hz. See http://jclahr.co= m/science/psn/roberts/index.html =20 It was first used on geophones.=20
    Below this to about rf / 10, (=3D 1/20 Hz) th= e gain=20 increases as 1 / f^2, so compensating the f^2 falling output to give a fla= t=20 characteristic. So you can extend a 2 second period vertical sensor out to= about=20 20 seconds quite easily. Extending the period much beyond x10 quickly runs= into=20 noise problems with a coil + magnet velocity detector. You need two= of=20 these stages with maximum gains of x10 (total x100 at 20=20 seconds) linked by a 2 pole high pass filter at ~ 1/30 Hz. Lennartz= use a=20 system like this. So do I and it works fine.
    Direct digital period compensation probably= works=20 best with 24 bit ADCs. The French use it on their schools system. 16 bit= ADCs=20 may only show a few counts (1/100 the rest of the signal) at x10 period,= unless=20 the gain is quite high and it may be partly masked by electronic=20 noise.
 
    Regards,
 
    Chris Chapman
 
Subject: Re: Vertical vs. Horz. From: Barry Lotz barry_lotz@............. Date: Tue, 22 Dec 2009 19:53:16 -0800 (PST) Chris To extent to sensor period what about using winquake and imposing a 2 pole = low pass filter to the signal's fft=A0 starting at the sensors rf?=20 On a different note , could there be a vertical component to the P wave due= to the angle of wave to the earths tangent due to the depth of the hypocen= ter ? Regards Barry http://www.seismicvault.com --- On Tue, 12/22/09, ChrisAtUpw@....... wrote: From: ChrisAtUpw@....... Subject: Re: Vertical vs. Horz. To: psn-l@.............. Date: Tuesday, December 22, 2009, 6:32 PM =0A=0A =0A=0AIn a message dated 22/12/2009, brett3nt@............. writes:c= lip- =A0=0A=A0=A0=A0=A0The Roberts' period compensating amplifier circuit =0Ais = probably the easiest technique for amateurs to use. It has constant gain fr= om =0Athe LP filter down to ~ the resonant frequency rf=A0of the vertical s= ensor, =0Aat say 1/2 Hz. See http://jclahr.com/science/psn/roberts/index.ht= ml=A0 =0AIt was first used on geophones. =0A=A0=A0=A0=A0Below this to about= rf / 10, (=3D 1/20 Hz) the gain =0Aincreases as 1 / f^2, so compensating t= he f^2 falling output to give a flat =0Acharacteristic. So you can extend a= 2 second period vertical sensor out to about =0A20 seconds quite easily. E= xtending the period much beyond x10 quickly runs into =0Anoise problems wit= h a coil + magnet velocity detector.=A0You need two of =0Athese stages with= =A0maximum gains of x10 (total x100 at 20 =0Aseconds)=A0linked by a 2 pole = high pass filter at ~ 1/30 Hz. Lennartz use a =0Asystem like this. So do I = and it works fine.=0A=A0=A0=A0=A0Direct digital period compensation probabl= y works =0Abest with 24 bit ADCs. The French use it on their schools system= .. 16 bit ADCs =0Amay only show a few counts (1/100 the rest of the signal) = at x10 period, unless =0Athe gain is quite high and it may be partly masked= =A0by electronic =0Anoise.=0A=A0=0A=A0=A0=A0=A0Regards,=0A=A0=0A=A0=A0=A0= =A0Chris Chapman=0A=A0 Subject: Re: Vertical vs. Horz. From: Brett Nordgren brett3nt@............. Date: Wed, 23 Dec 2009 09:38:16 -0500 Hi Chris, At 09:32 PM 12/22/2009 -0500, you wrote: >In a message dated 22/12/2009, brett3nt@............. writes: >> >1 I know this is an over simplification, but does the P arrives at an >> >angle (bottom to top) and this influences the spring? >>What you suggest I believe is true, that P waves may have some vertical >>component, i.e., they arrive at some angle to the horizontal, as you say. > It may have even more to deal with the curved paths that the rays > travel inside the spherical earth! >> >The obvious advantage of a vertical is they see many earthquakes, the >> >disadvantage they are limited and also see a lot of other things which are >> >not earthquakes. All of my verticals have been 1 to 2.5 seconds. >> > A typical vertical sensor recording will have a trace of 20 >> >mins vs. a 3 hours trace on the Lehman. > > This must be an observational error. The noise on an uncased, > uncompensated vertical may be over 20x that on a horizontal. The noise on > verticals is only less at longer periods since atmospheric noise is > excluded in contemporary seismometers by the hermetically sealed case. For a good comparison of vertical vs horizontal noise see http://bnordgren.org/seismo/TrilliumZN.gif which shows the vertical and N-S channels of the Trillium over a couple of hours this morning. They have the same gain and are both low pass filtered at 0.08 seconds to cut out most microseisms. The N-S trace is the red one. Don't even think of making a sensitive vertical without a pressure case. As you rightly point out, it won't work. >>The only problem is that the movement of a seismometer in response to an >>error force, such as from small temperature changes, etc. increases as >>1/Frequency^2 > Even more critical are air density changes effecting a vertical > sensor and also wind noise. Temperatures should change quite slowly > inside an insulating case, assuming that the sun does not shine on it! Air density changes are readily dealt with by the pressure case. Wind noise has not often been a problem (except for yesterday), certainly less than for the horizontals. Temperature change rates are a big problem, with instruments responding to milli-degrees per hour. A 500 sec high pass takes care of that, though you need to make sure that the instrument isn't creating significant "DC" levels at its output. Thick insulation is rather effective at slowing down temperature rates. >>It is way harder to make a stable instrument for 50 >>seconds than for 10 or 20 or 6. Long period verticals almost certainly >>need to use a feedback design if they are going to be sensitive enough to >>see distant quakes while at the same time, insensitive enough to >>temperature and other variations to not wander off to maximum output. > > Uh, Uh! Now define what you are calling long period? Ones with lower corner frequencies in the 20-120 second range, though I suggest that the use of feedback becomes more beneficial the lower you go. > The Roberts' period compensating amplifier circuit is probably the > easiest technique for amateurs to use. It has constant gain from the LP > filter down to ~ the resonant frequency rf of the vertical sensor, at say > 1/2 Hz. See > http://jclahr.com/science/psn/roberts/index.html > It was first used on geophones. > Below this to about rf / 10, (= 1/20 Hz) the gain increases as 1 / > f^2, so compensating the f^2 falling output to give a flat > characteristic. So you can extend a 2 second period vertical sensor out > to about 20 seconds quite easily. Extending the period much beyond x10 > quickly runs into noise problems with a coil + magnet velocity detector. > You need two of these stages with maximum gains of x10 (total x100 at 20 > seconds) linked by a 2 pole high pass filter at ~ 1/30 Hz. Lennartz use a > system like this. So do I and it works fine. > Direct digital period compensation probably works best with 24 bit > ADCs. The French use it on their schools system. 16 bit ADCs may only > show a few counts (1/100 the rest of the signal) at x10 period, unless > the gain is quite high and it may be partly masked by electronic noise. I agree, that's a good technique. Dave uses it in his miniature horizontal designs with great success. My only concern, is that you are limited in how much you can use for the reasons you suggest. Sensitive verticals may not be sufficiently stable in the DC sense to allow for longer-period instruments using that technique. They would have a tendency to drift to the stops. Regards, Brett Watch our wiggles http://bnordgren.org/seismo/gif_images.htm or watch some very very good wiggles http://aslwww.cr.usgs.gov/Seismic_Data/telemetry_data/ANMO_24hr.html __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Microseism modulation From: "Randy Pratt" rpratt@............. Date: Wed, 23 Dec 2009 10:31:35 -0600 Dr Peters, I very much agree the pattern appears related to a modulation of some = sort. If I understand correctly what you are looking for could someone = not create a sideband plot of the filtered data and then obtain the = frequencies of interest simply from an FFT of the sideband? Randy
Dr Peters,
 
I very much agree the pattern appears = related to a=20 modulation of some sort.  If I understand correctly what you are = looking=20 for could someone not create a sideband plot of the filtered data = and then=20 obtain the frequencies of interest simply from an FFT of the=20 sideband?
 
Randy
Subject: sideband plot from microseisms From: Randall Peters PETERS_RD@.......... Date: Wed, 23 Dec 2009 17:13:48 -0500 Randy, It appears that you are an amateur radio operator. Indeed, if a sideb= and plot could be readily generated, all of the information I'm looking for= would be there for the taking. Unfortunately I'm not sure how to produce = such a plot. I suppose one could save (export) the FFT values using one of= the pieces of Larry's code, copy these into Excel and then use some algori= thm that is part of the Excel library. If you have some clever ideas on ho= w to reduce the manual labor required to quantify the sideband values I wil= l be very interest to hear about them. Randall= __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Long Frequency noise? From: "Ted Channel" tchannel@............ Date: Wed, 23 Dec 2009 18:59:44 -0700 Hi Folks, I just recorded the 6.3M Primor'ye Russia, on three sensors, = a Lehman, a Vertical and a new horz I call ch 2. The Ch 2 sensor is new, and has a period of 22 second, horz pendulum = like a Lehman. This new sensor has always had (long period noise)? = FFT...... This was the first earthquake I have received since I = installed it. I normally filter 1 for low pass, .05 for high = pass................This time I had to use 1 for low pass and .5 for = high pass, to clean it up. I can send all three .psn files, all unfiltered, if you think you can = tell me what is causing the noise. I won't try to go into great = detail here. All three sensor recorded it clearly buy something is not = right. Thanks, Ted
Hi Folks,  I just recorded the = 6.3M Primor'ye=20 Russia,  on three sensors, a Lehman, a Vertical and a new horz I = call ch=20 2.
 
The Ch 2 sensor is new, and has a = period of 22=20 second, horz pendulum like a Lehman.   This new sensor has = always had=20 (long period noise)?  FFT...... This was the first earthquake = I have=20 received since I installed it.   I normally filter 1 for low = pass, .05=20 for high pass................This time I had to use 1 for low pass and = ..5 for=20 high pass, to clean it up.
 
I can send all three .psn files, all = unfiltered, if=20 you think you can tell me what is causing the noise.    I = won't=20 try to go into great detail here.   All three sensor recorded = it=20 clearly buy something is not right.
 
Thanks, Ted
Subject: Re: Long Frequency noise? From: Barry Lotz barry_lotz@............. Date: Wed, 23 Dec 2009 18:42:20 -0800 (PST) Ted In light of the recent discussions, the 6.3M Primor'ye =0ARussia event I re= corded didn't contain any real surface waves. I got P, PP and S only.=20 Regards Barry http://www.seismicvault.com --- On Wed, 12/23/09, Ted Channel wrote: From: Ted Channel Subject: Long Frequency noise? To: "psn" Date: Wednesday, December 23, 2009, 5:59 PM =0A=0A =0A =0A=0AHi Folks,=A0 I just recorded the 6.3M Primor'ye =0ARussia,= =A0 on three sensors, a Lehman, a Vertical and a new horz I call ch =0A2.= =0A=A0=0AThe Ch 2 sensor is new, and has a period of 22 =0Asecond, horz pen= dulum like a Lehman.=A0=A0 This new sensor has always had =0A(long period n= oise)?=A0=A0FFT...... This was the first earthquake I have =0Areceived sinc= e I installed it.=A0=A0 I normally filter 1 for low pass, .05 =0Afor high p= ass................This time I had to use 1 for low pass and .5 for =0Ahigh= pass, to clean it up.=0A=A0=0AI can send all three .psn files, all unfilte= red, if =0Ayou think you can tell me what is causing the noise.=A0=A0=A0 I = won't =0Atry to go into great detail here.=A0=A0 All three sensor recorded = it =0Aclearly buy something is not right.=0A=A0=0AThanks, Ted
Chris
To extent to sensor period what abou= t using winquake and imposing a 2 pole low pass filter to the signal's fft  starting at the se= nsors rf?
On a different note , could there be a vertical component to = the P wave due to the angle of wave to the earths tangent due to the depth = of the hypocenter ?

Regards
Barry
http://www.seismicvault.com=

--- On Tue, 12/22/09, ChrisAtUpw@....... <ChrisAtUpw@...... om> wrote:

From: ChrisAtUpw@..... com <ChrisAtUpw@.......>
Subject: Re: Vertical vs. Horz.
To: ps= n-l@..............
Date: Tuesday, December 22, 2009, 6:32 PM

=0A=0A =0A=0A
In a message dated 22/12/2009, brett3nt= @............. writes:
clip-
 
=0A
  &= nbsp; The Roberts' period compensating amplifier circuit =0Ais probabl= y the easiest technique for amateurs to use. It has constant gain from =0At= he LP filter down to ~ the resonant frequency rf of the vertical senso= r, =0Aat say 1/2 Hz. See http://jclahr.com/science/psn/roberts/index.h= tml  =0AIt was first used on geophones. =0A
   =  Below this to about rf / 10, (=3D 1/20 Hz) the gain =0Aincreases as 1= / f^2, so compensating the f^2 falling output to give a flat =0Acharacteri= stic. So you can extend a 2 second period vertical sensor out to about =0A2= 0 seconds quite easily. Extending the period much beyond x10 quickly runs i= nto =0Anoise problems with a coil + magnet velocity detector. You need= two of =0Athese stages with maximum gains of x10 (total x100 at 20 = =0Aseconds) linked by a 2 pole high pass filter at ~ 1/30 Hz. Lennartz= use a =0Asystem like this. So do I and it works fine.
=0A
 &= nbsp;  Direct digital period compensation probably works =0Abest = with 24 bit ADCs. The French use it on their schools system. 16 bit ADCs = =0Amay only show a few counts (1/100 the rest of the signal) at x10 period,= unless =0Athe gain is quite high and it may be partly masked by elect= ronic =0Anoise.
=0A
 
=0A
    Re= gards,
=0A
 
=0A
    Chris Chapm= an
=0A
 
Ted
In light of = the recent discussions, the 6.3M Primor'ye = =0ARussia event I recorded didn't contain any real surface waves. I = got P, PP and S only.

Regards
Barry
http://www.seismicvault.com

--- On Wed, 12/23/09, Ted Channel <tchannel@............ t> wrote:

From: Ted Channel <= tchannel@............>
Subject: Long Frequency noise?
To: "psn" &l= t;psn-l@..............>
Date: Wednesday, December 23, 2009, 5:59 PM
=0A=0A =0A =0A=0A
Hi Folks,  I just recorded the 6.3M Primor'y= e =0ARussia,  on three sensors, a Lehman, a Vertical and a new horz I = call ch =0A2.
=0A
&n= bsp;
=0A
The Ch 2 sensor is new, a= nd has a period of 22 =0Asecond, horz pendulum like a Lehman.   T= his new sensor has always had =0A(long period noise)?  FFT...... = This was the first earthquake I have =0Areceived since I installed it. = ;  I normally filter 1 for low pass, .05 =0Afor high pass.............= ....This time I had to use 1 for low pass and .5 for =0Ahigh pass, to clean = it up.
=0A
 =0A
I can send all three .psn files,= all unfiltered, if =0Ayou think you can tell me what is causing the noise.=     I won't =0Atry to go into great detail here.  = All three sensor recorded it =0Aclearly buy something is not right.=
=0A
 
=0A
Thanks, Ted
Subject: Re: Long Frequency noise? From: chrisatupw@....... Date: Thu, 24 Dec 2009 08:51:50 EST In a message dated 24/12/2009, tchannel@............ writes: Hi Folks, I just recorded the 6.3M Primor'ye Russia, on three sensors, a Lehman, a Vertical and a new horz I call ch 2. The Ch 2 sensor is new, and has a period of 22 second, horz pendulum like a Lehman. This new sensor has always had (long period noise)? FFT...... This was the first earthquake I have received since I installed it. I normally filter 1 for low pass, .05 for high pass................This time I had to use 1 for low pass and .5 for high pass, to clean it up. I can send all three .psn files, all unfiltered, if you think you can tell me what is causing the noise. Hi Ted, I will have a look if you like. What is the construction of Ch 2, please? Regards, Chris Chapman
In a message dated 24/12/2009, tchannel@............ writes:
Hi Folks,  I just recorded the 6.3= M=20 Primor'ye Russia,  on three sensors, a Lehman, a Vertical and a new= horz=20 I call ch 2.
 
The Ch 2 sensor is new, and has a perio= d of 22=20 second, horz pendulum like a Lehman.   This new sensor has alw= ays=20 had (long period noise)?  FFT...... This was the first earthqu= ake I=20 have received since I installed it.   I normally filter 1 for= low=20 pass, .05 for high pass................This time I had to use 1 for low= pass=20 and .5 for high pass, to clean it up.
 
I can send all three .psn files, all un= filtered,=20 if you think you can tell me what is causing the=20 noise. 
Hi Ted,
 
    I will have a look if you like. What is the= =20 construction of Ch 2, please?
 
    Regards,
 
    Chris Chapman
Subject: Sideband information From: "Randy Pratt" rpratt@............. Date: Thu, 24 Dec 2009 11:31:51 -0600 Dr Peters, After suggesting the sideband method I began researching how. It = appears doing this digitally is a bit more complex than anticipated. I = did find that people in other fields such as ultrasound are using a = Hilbert transform to produce the information. I don't know what = obstacles this would involve as to sample rate limits or translation to = the extremely low frequencies from the MHz ranges they are using. It = looks like an interesting topic for winter night study. AmaSeis can = export the FFT of a segment of data as a starting point or an FFT = followed by the Hilbert transform could be coded directly once all the = limitations are known. I wonder if an analog demodulator could be added to the seismograph = using the microseism frequency of a second instrument as a continuous = tuning device for the carrier wave. Randy=20
Dr Peters,
 
After suggesting the sideband method I = began=20 researching how.  It appears doing this digitally is a bit more = complex=20 than anticipated.  I did find that people in other fields such as=20 ultrasound are using a Hilbert transform to produce the = information.  I=20 don't know what obstacles this would involve as to sample rate limits or = translation to the extremely low frequencies from the MHz ranges they = are=20 using.   It looks like an interesting topic for winter night=20 study.  AmaSeis can export the FFT of a segment of data as a = starting=20 point or an FFT followed by the Hilbert transform could be coded = directly=20 once all the limitations are known.
 
I wonder if an analog demodulator could = be added to=20 the seismograph using the microseism frequency of a second = instrument as a=20 continuous tuning device for the carrier wave.
 
Randy 
Subject: long freq. noise From: "Ted Channel" tchannel@............ Date: Thu, 24 Dec 2009 11:07:48 -0700 Hi Folks, I added a heat source, light bulb, to the top area of my = vault. I could see at once this was a big big help. In this pit are = three sensors, each has a cover of some kind. Ch 1 is a Lehman 20 seconds, covered with a large Styrofoam box, not air = tight, just some butt joints and a bit of tape. ( no noise problems) Ch 2 is 22 seconds, covered with a large Styrofoam box, not air tight, = no tape, butt joints. (big noise problems) with frequencies of 15 = to 60 seconds Ch 3 is a vertical, housed in its own plastic enclosure, fairly tight. = (no noise problems) other than the high frequencies stuff, which the = vertical picks up. I just added a heat source,inside the pit, did a before and after, FFT = on all three sensors, and see a big improvement. Especially on Ch 2, = not much on the other two. I can email images. I know this may not be the only issue, but it made a 100% improvement. To better explain this let me say the pit 4'x4'x6' lined with blocks. = Along the top edge of the pit, I added 4" of insulation batting. On = top of that I added 1" ridged Styrofoam panels taped to form a lid. I added bricks to compress all and form a tighter lid. The pit is = under the house in the craw space, 24" from any footing. The craw space = seem quiet, I can not feel any air currents, no wind blowing. No duct work, blowing air. No temperature changes, 52 degrees for a = low and 55 for a high, out side pit, less inside the pit. Obviously, air must be circulating or otherwise influencing into the = bottom of the pit. The heat source in layering the air in the pit, and = minimizing the turbulence. Any similar observation? and or advice. I am surprised because I thought the boxes plus lid, would do the job. = Before I rework the boxes, taping, insulating etc. Perhaps I should = address the lid and make it thicker, from 1" to 6" batting, and improve = the lid seal. Maybe I should do all of it. I could also leave the heat source, especially if that is the real fix. = =20 Merry Christmas, Ted
Hi Folks,   I added a heat = source, light=20 bulb, to the top area of my vault.   I could see at once this = was a=20 big big help.   In this pit are three sensors, each has a = cover of=20 some kind.
Ch 1 is a Lehman 20 seconds, covered = with a large=20 Styrofoam box, not air tight, just some butt joints and a bit of = tape.  (=20 no noise problems)
Ch 2 is 22 seconds, covered with a = large Styrofoam=20 box, not air tight, no tape, butt = joints.     (big=20 noise problems)  with frequencies of 15 to 60 seconds
Ch 3 is a vertical, housed in its own = plastic=20 enclosure, fairly tight.  (no noise problems) other than the high=20 frequencies stuff, which the vertical picks up.
 
I just added a heat source,inside the = pit, did=20 a before and after, FFT on all three sensors, and see a big=20 improvement.   Especially on Ch 2, not much on the other=20 two.   I can email images.
 
I know this may not be the only issue, = but it made=20 a 100% improvement.
 
To better explain this let me say the = pit 4'x4'x6'=20 lined with blocks.  Along the top edge of the pit, I added 4" of = insulation=20 batting.   On top of that I added 1" ridged Styrofoam panels = taped to=20 form a lid.
I added bricks to compress all and form = a tighter=20 lid.   The pit is under the house in the craw space, 24" from = any=20 footing.  The craw space seem quiet, I can not feel any air = currents, no=20 wind blowing.
No duct work, blowing air.   = No=20 temperature changes,  52 degrees for a low and 55 for a high, out = side pit,=20 less inside the pit.
 
Obviously, air must be circulating or = otherwise=20 influencing into the bottom of the pit.   The heat source in = layering=20 the air in the pit, and minimizing the turbulence.
 
Any similar observation?  and or=20 advice.
 
I am surprised because I thought the = boxes plus=20 lid, would do the job.   Before I rework the boxes, taping, = insulating=20 etc.   Perhaps I should address the lid and make it thicker, = from 1"=20 to 6" batting, and improve the lid seal.   Maybe I should do = all of=20 it.
 
I could also leave the heat source, = especially if=20 that is the real fix.  
 
Merry Christmas,
Ted
 
 
 
Subject: Re: long freq. noise From: chrisatupw@....... Date: Thu, 24 Dec 2009 13:55:35 EST In a message dated 24/12/2009, tchannel@............ writes: Hi Folks, I added a heat source, light bulb, to the top area of my vault. I could see at once this was a big big help. In this pit are three sensors, each has a cover of some kind. Hi Ted, I keep well away from light bulbs. They attract too many insects, mice etc. This is just swapping one problem for several others. Too much heat from a concentrated source like a light bulb can also be noisy. I seal the seismometer covers. I buy a can of spray grouting, roughly assemble the polystyrene sheet sides with tape, run a very wet cloth over the insides of all joints, spray on the grouting, close the joints with tape and use a paint scraper to remove excess foam. I then stick the top on and tape it in place. DigiKey etc keep high power resistors in Aluminum cases with bolt holes. I buy two of these and a high wattage wall-wort AC transformer. Bolt two resistors to Al sheet and mount inside the top of each foam housing. You need maybe 10 watts each seismometer. Ch 1 is a Lehman 20 seconds, covered with a large Styrofoam box, not air tight, just some butt joints and a bit of tape. ( no noise problems) Ch 2 is 22 seconds, covered with a large Styrofoam box, not air tight, no tape, butt joints. (big noise problems) with frequencies of 15 to 60 seconds Ch 3 is a vertical, housed in its own plastic enclosure, fairly tight. (no noise problems) other than the high frequencies stuff, which the vertical picks up. I just added a heat source,inside the pit, did a before and after, FFT on all three sensors, and see a big improvement. Especially on Ch 2, not much on the other two. I can email images. I know this may not be the only issue, but it made a 100% improvement. To better explain this let me say the pit 4'x4'x6' lined with blocks. Along the top edge of the pit, I added 4" of insulation batting. On top of that I added 1" ridged Styrofoam panels taped to form a lid. I added bricks to compress all and form a tighter lid. The pit is under the house in the craw space, 24" from any footing. The crawl space seem quiet, I can not feel any air currents, no wind blowing. No duct work, blowing air. No temperature changes, 52 degrees for a low and 55 for a high, out side pit, less inside the pit. Reverse convection / convection / draft noise may be way, way below what you can feel. Check with smoke from a cigarette? Obviously, air must be circulating or otherwise influencing into the bottom of the pit. The heat source in layering the air in the pit, and minimizing the turbulence. Could this be just drafts? Any similar observation? and or advice. I am surprised because I thought the boxes plus lid, would do the job. Before I rework the boxes, taping, insulating etc. Perhaps I should address the lid and make it thicker, from 1" to 6" batting, and improve the lid seal. Maybe I should do all of it. I could also leave the heat source, especially if that is the real fix. I would make the individual boxes first. Can you use a sheet of polythene to cover the top of the pit? Weight it down all around with cloth tubes filled with sand? Regards, Chris Chapman
In a message dated 24/12/2009, tchannel@............ writes:
Hi Folks,   I added a heat so= urce,=20 light bulb, to the top area of my vault.   I could see at once= this=20 was a big big help.   In this pit are three sensors, each has= a=20 cover of some kind.
Hi Ted,
 
    I keep well away from light bulbs. They attra= ct too=20 many insects, mice etc. This is just swapping one problem for several othe= rs.=20 Too much heat from a concentrated source like a light bulb can also be=20 noisy.
    
    I seal the seismometer covers. I buy a can of= spray=20 grouting, roughly assemble the polystyrene sheet sides with tape, run a ve= ry wet=20 cloth over the insides of all joints, spray on the grouting, close the joi= nts=20 with tape and use a paint scraper to remove excess foam. I then stick the= top on=20 and tape it in place.
 
    DigiKey etc keep high power resistors in Alum= inum=20 cases with bolt holes. I buy two of these and a high wattage wall-wort AC= =20 transformer.  Bolt two resistors to Al sheet and mount inside the top= of=20 each foam housing. You need maybe 10 watts each seismometer.
Ch 1 is a Lehman 20 seconds, covered wi= th a large=20 Styrofoam box, not air tight, just some butt joints and a bit of tape.&n= bsp; (=20 no noise problems)
Ch 2 is 22 seconds, covered with a larg= e=20 Styrofoam box, not air tight, no tape, butt=20 joints.     (big noise problems)  with=20 frequencies of 15 to 60 seconds
Ch 3 is a vertical, housed in its own= plastic=20 enclosure, fairly tight.  (no noise problems) other than the high= =20 frequencies stuff, which the vertical picks up.
 
I just added a heat source,inside the= =20 pit, did a before and after, FFT on all three sensors, and see a bi= g=20 improvement.   Especially on Ch 2, not much on the other=20 two.   I can email images.
 
I know this may not be the only issue,= but it=20 made a 100% improvement.
 
To better explain this let me say the= pit=20 4'x4'x6' lined with blocks.  Along the top edge of the pit, I added= 4" of=20 insulation batting.   On top of that I added 1" ridged Styrofo= am=20 panels taped to form a lid.
I added bricks to compress all and form= a tighter=20 lid.   The pit is under the house in the craw space, 24" from= any=20 footing.  The crawl space seem quiet, I can not feel any air curren= ts, no=20 wind blowing.
No duct work, blowing air.  = No=20 temperature changes,  52 degrees for a low and 55 for a high, out= side=20 pit, less inside the pit.
    Reverse convection / convection / draft noise= =20 may be way, way below what you can feel. Check with smoke from= a=20 cigarette?
Obviously, air must be circulating or= otherwise=20 influencing into the bottom of the pit. The heat source in layering= the=20 air in the pit, and minimizing the turbulence.
    Could this be just drafts? 
Any similar observation?  and or= =20 advice.
 
I am surprised because I thought the bo= xes plus=20 lid, would do the job.   Before I rework the boxes, taping,=20 insulating etc.   Perhaps I should address the lid and make it= =20 thicker, from 1" to 6" batting, and improve the lid seal.   Ma= ybe I=20 should do all of it.
 
I could also leave the heat source, esp= ecially if=20 that is the real fix.  
    I would make the individual boxes first. Can= you=20 use a sheet of polythene to cover the top of the pit? Weight it down all= around=20 with cloth tubes filled with sand?
 
    Regards,
 
    Chris Chapman
Subject: Re: long freq. noise From: "GPayton" gpayton@............. Date: Thu, 24 Dec 2009 13:41:48 -0600 Ted, Here is a page on Digi-Key webpage with the resistors Chris suggested. http://search.digikey.com/scripts/DkSearch/dksus.dll?Selection However, I'd like him to comment on "wirewound" vs. "composit" regarding possible noise generated. A wirewound resistor seems to me to be nothing but a coil and possible antenna. I wonder if he meant ac/dc wall wart or ac/ac wall wart? Merry Christmas to EVERYONE on the list. Jerry
Ted,  Here is a page = on Digi-Key=20 webpage with the resistors Chris suggested. 
h= ttp://search.digikey.com/scripts/DkSearch/dksus.dll?Selection<= /DIV>
 
However, I'd like him to = comment on=20 "wirewound" vs. "composit" regarding possible noise generated.  A = wirewound=20 resistor seems to me to be nothing but a coil and possible = antenna. =20
 
I wonder if he=20 meant ac/dc wall wart or ac/ac wall wart?
 
Merry Christmas to EVERYONE = on the=20 list.
 
Jerry
 
Subject: Re: long freq. noise From: chrisatupw@....... Date: Thu, 24 Dec 2009 17:11:49 EST In a message dated 24/12/2009, gpayton@............. writes: Ted, Here is a page on Digi-Key webpage with the resistors Chris suggested. _http://search.digikey.com/scripts/DkSearch/dksus.dll?Selection_ (http://search.digikey.com/scripts/DkSearch/dksus.dll?Selection) Hi Gerry, Check out RHRB-x-ND where x is the value in Ohms ie 10,15, 25 _http://search.digikey.com/scripts/DkSearch/dksus.dll?Cat=66696_ (http://search.digikey.com/scripts/DkSearch/dksus.dll?Cat=66696) Ohmite, Huntington, Vishay-Dale, wire wound, bolt on, lug end, 10w, 1% However, I'd like him to comment on "wirewound" vs. "composit" regarding possible noise generated. A wirewound resistor seems to me to be nothing but a coil and possible antenna. You use wire wound resistors to give a high dissipation and stable characteristics. They run quite hot. You can buy non inductive wire wound resistors, but they are not neccessary. Vishay seem to be the cheapest. I use 1/16" sheet Aluminum. I wonder if he meant ac/dc wall wart or ac/ac wall wart? AC / AC wall wort - the cheapest and highest voltage to suit - 24V? Merry Christmas to EVERYONE on the list. Regards, Chris Chapman
In a message dated 24/12/2009, gpayton@............. writes:
Ted,  Here is a page= on Digi-Key=20 webpage with the resistors Chris suggested. 
Hi Gerry,
 
    Check out RHRB-x-ND where x is the value in= Ohms ie=20 10,15, 25
    http://search.digikey.com/scripts/DkSearc= h/dksus.dll?Cat=3D66696 Ohmite,=20 Huntington, Vishay-Dale, wire wound, bolt on, lug end, 10w, 1%
However, I'd like him to co= mment on=20 "wirewound" vs. "composit" regarding possible noise generated.  A= =20 wirewound resistor seems to me to be nothing but a coil and possible=20 antenna. 
    You use wire wound resistors to give a high= =20 dissipation and stable characteristics. They run quite hot.
You can buy non inductive wire wound resistors, but they are not=20 neccessary. Vishay seem to be the cheapest.
    I use 1/16" sheet Aluminum.
I wonder if=20 he meant ac/dc wall wart or ac/ac wall=20 wart?
    AC / AC wall wort - the cheapest and highest= =20 voltage to suit - 24V?
Merry Christmas to EVERYONE= on the=20 list.
    Regards,
 
    Chris Chapman
Subject: Re: Long Frequency noise? From: "Dale Hardy" photon1@........... Date: Sat, 26 Dec 2009 10:26:15 +1100 Hi Ted, can you send me the files to have a look at please, also do you have any = electronics inside the seismometer enclosures which may be adding = convective heating and turbulence ? thanks Dale ----- Original Message -----=20 From: Ted Channel=20 To: psn=20 Sent: Thursday, December 24, 2009 12:59 PM Subject: Long Frequency noise? Hi Folks, I just recorded the 6.3M Primor'ye Russia, on three = sensors, a Lehman, a Vertical and a new horz I call ch 2. The Ch 2 sensor is new, and has a period of 22 second, horz pendulum = like a Lehman. This new sensor has always had (long period noise)? = FFT...... This was the first earthquake I have received since I = installed it. I normally filter 1 for low pass, .05 for high = pass................This time I had to use 1 for low pass and .5 for = high pass, to clean it up. I can send all three .psn files, all unfiltered, if you think you can = tell me what is causing the noise. I won't try to go into great = detail here. All three sensor recorded it clearly buy something is not = right. Thanks, Ted
Hi Ted,
can you send me the files to have a = look at please,=20 also do you have any electronics inside the seismometer enclosures which = may be=20 adding convective heating and turbulence ?
thanks
Dale
----- Original Message -----
From:=20 Ted=20 Channel
To: psn
Sent: Thursday, December 24, = 2009 12:59=20 PM
Subject: Long Frequency = noise?

Hi Folks,  I just recorded the = 6.3M=20 Primor'ye Russia,  on three sensors, a Lehman, a Vertical and a = new horz=20 I call ch 2.
 
The Ch 2 sensor is new, and has a = period of 22=20 second, horz pendulum like a Lehman.   This new sensor has = always=20 had (long period noise)?  FFT...... This was the first = earthquake I=20 have received since I installed it.   I normally filter 1 = for low=20 pass, .05 for high pass................This time I had to use 1 for = low pass=20 and .5 for high pass, to clean it up.
 
I can send all three .psn files, all = unfiltered,=20 if you think you can tell me what is causing the = noise.    I=20 won't try to go into great detail here.   All three sensor = recorded=20 it clearly buy something is not right.
 
Thanks, = Ted
Subject: Posted a video of my seismic amplifier on a binary news site From: "Geoffrey" gmvoeth@........... Date: Sat, 26 Dec 2009 07:53:00 -0700 Check out the following site alt.binaries.schematics.electronics for files (42 of them about 257KB each ) You need to fetch all of them. SEISMIC_STATION_AVI_PAR2_RAR.rar[01/42] to SEISMIC_STATION_AVI_PAR2_RAR.rar[42/42] you can use your email client to download and reassemble ( combine and decode ) this file into an RAR file then use RAR to extract it then use PAR2 to form the final AVI file which can be played to show my entire front office recorder setup here at GVA. YOU need like 1. OUTLOOK EXPRESS or WINDOWS MAIL 2. ACCESS to the news group 3. RAR decoder 4. PAR2 decoder 5. AVI player ( a small multimedia player like memorex will work) it is 320 X 240 with silly audio playing in the background. but it shows you how ridiculous my setup is compared with yours. Cheers geoff __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Banda Sea 12.26.09 From: Thomas Dick dickthomas01@............. Date: Sat, 26 Dec 2009 12:07:23 -0600 At 132 deg on vertical AS-1 I seem to see two large diffP spikes about 8 seconds apart ... did anyone else get this or was this an aberation? __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Banda Sea 12.26.09 From: "Geoffrey" gmvoeth@........... Date: Sat, 26 Dec 2009 11:37:48 -0700 All I can say is that if you are within the shadow zone you can seem to get strange results that do not seem to match anything you are used to seeing before the shadow zone. I miss most signals under a Mag7 after the shadow zone. ----- Original Message ----- From: "Thomas Dick" To: Sent: Saturday, December 26, 2009 11:07 AM Subject: Banda Sea 12.26.09 > At 132 deg on vertical AS-1 I seem to see two large diffP spikes about 8 > seconds apart ... did anyone else get this or was this an aberation? > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Note On Noise From: "Geoffrey" gmvoeth@........... Date: Sat, 26 Dec 2009 11:52:30 -0700 You guys with those low freq sensors below 5 seconds seem terribly plagued by noise either seismic or weather or whatever. I was wondering if it is possible for you to study the noise when no EQ are present then use that data to somehow filter out the background stuff and this may serve to enhance the eq stuff. To me your signals appear swamped with noise at the same freq as the signal which literally makes it impossible to filter out the noise. If you are not anti alizing things you could be getting noise from much higher more intense things like air conditioners and other machines on the ground. A 26 Hz signal may look like one Hz if it alizes with a 50SPS sample rate. Just a thought, geoff ps has anyone ever put their device into a vacuum chamber to eliminate air / air buoyancy changes from effecting their noise levels ? Surrounding their device with gallon jugs filled with water at room temperature to act as a thermal condenser ? ( moderate temp changes ) things like this ??? __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: RE: Posted a video of my seismic amplifier on a binary news site From: "Gary Lindgren" gel@................. Date: Sat, 26 Dec 2009 12:22:03 -0800 Geoff, How about posting the video on YouTube. That's much easier to use. Gary -----Original Message----- From: psn-l-request@.............. [mailto:psn-l-request@............... On Behalf Of Geoffrey Sent: Saturday, December 26, 2009 6:53 AM To: PSN-LIST Subject: Posted a video of my seismic amplifier on a binary news site Check out the following site alt.binaries.schematics.electronics for files (42 of them about 257KB each ) You need to fetch all of them. SEISMIC_STATION_AVI_PAR2_RAR.rar[01/42] to SEISMIC_STATION_AVI_PAR2_RAR.rar[42/42] you can use your email client to download and reassemble ( combine and decode ) this file into an RAR file then use RAR to extract it then use PAR2 to form the final AVI file which can be played to show my entire front office recorder setup here at GVA. YOU need like 1. OUTLOOK EXPRESS or WINDOWS MAIL 2. ACCESS to the news group 3. RAR decoder 4. PAR2 decoder 5. AVI player ( a small multimedia player like memorex will work) it is 320 X 240 with silly audio playing in the background. but it shows you how ridiculous my setup is compared with yours. Cheers geoff __________________________________________________________ Public Seismic Network Mailing List (PSN-L) __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Posted a video of my seismic amplifier on a binary news site From: "Geoffrey" gmvoeth@........... Date: Sat, 26 Dec 2009 21:43:21 -0700 Yes, Possibly so yet I tried to post the AVI file as ABCDEFGH.AVI under SCIENCE and TECHNOLOGY but something must have gone wrong because it never showed up as being uploaded. I think that Utube may want a form that Im unable to transcode. Like MP2. My camera only makes MOV files then i got this little free encoder designed to work with the memorex MMP as a 320X240 AVI file with sound. It seems utube did not like the avi file i sent it yet it works well on my machines. Id be happy to send split RAR or ZIP or EXE archive the avi file and send it to you as a series of attachments. The news group is just as easy to use if play in those places. Most ISP will give you a news service included with your internet & email stuff. Get a reader and a poster and the archiving tools most can be found throughout the internet. A few free but mostly not. I may try making a new one later but that one on the newsgroup is just as easy if you know how. I do not normally save such stuff on my machine for the future, it takes too much space. Regards, geoff ----- Original Message ----- From: "Gary Lindgren" To: Sent: Saturday, December 26, 2009 1:22 PM Subject: RE: Posted a video of my seismic amplifier on a binary news site > Geoff, > How about posting the video on YouTube. That's much easier to use. > Gary > > > > -----Original Message----- > From: psn-l-request@.............. [mailto:psn-l-request@............... On > Behalf Of Geoffrey > Sent: Saturday, December 26, 2009 6:53 AM > To: PSN-LIST > Subject: Posted a video of my seismic amplifier on a binary news site > > Check out the following site > alt.binaries.schematics.electronics > > for files (42 of them about 257KB each ) > You need to fetch all of them. > > SEISMIC_STATION_AVI_PAR2_RAR.rar[01/42] to > SEISMIC_STATION_AVI_PAR2_RAR.rar[42/42] > > you can use your email client to download > and reassemble ( combine and decode ) > this file into an RAR file then use > RAR to extract it then use PAR2 to > form the final AVI file which can > be played to show my entire front office > recorder setup here at GVA. > > YOU need like > 1. OUTLOOK EXPRESS or WINDOWS MAIL > 2. ACCESS to the news group > 3. RAR decoder > 4. PAR2 decoder > 5. AVI player ( a small multimedia player like memorex will work) > > it is 320 X 240 with silly audio playing in the background. > > but it shows you how ridiculous my setup is > compared with yours. > > Cheers > geoff > > > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. > > > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Verticals From: "Ted Channel" tchannel@............ Date: Sun, 27 Dec 2009 06:59:50 -0700 Hi Folks, I have downloaded Bob McClure's great program SpringCalc.exe. = I have put in some numbers and see it calculates very long periods = under certain conditions, periods of >20. My question is can long periods like these really be achieved? I have = build several models and some working sensors using this approach, but I = have never gotten more than about 3x the springs natural frequency. A = spring of .5 second, just hanging vertically, resulted in a sensor of = 1.5 seconds. I guess the AS1 is another example. The design of the = AS1 is widely used and am I correct that it is operating at about 1.5 = seconds? In theory, is this shape, capable >10 seconds? I hope to use Bob's program to construct another vertical, but I am = confused, about my results. I know there are methods for extending = the period, but here I am just asking about the physical results of = using a spring-supported pendulum constrained to move in a vertical = plane. Perhaps these calculated long periods would only be possible = under the best of conditions, where all factors were perfect. I seem = to get a period of around x3 that of the spring hanging vertical with = a mass. I have tried many different springs and the result were very = similar in achieving only x3. Thanks, Ted
Hi Folks,  I have downloaded Bob = McClure's=20 great program SpringCalc.exe.    I have put in some = numbers and=20 see it calculates very long periods under certain conditions, periods of = >20.
 
My question is can long periods like = these really=20 be achieved?    I have build several models and some = working=20 sensors using this approach, but I have never gotten more than about 3x = the=20 springs natural frequency.   A spring of .5 second, just = hanging=20 vertically, resulted in a sensor of 1.5 seconds.   I guess the = AS1 is=20 another example.   The design of the AS1 is widely used and am = I=20 correct that it is operating at about 1.5 seconds?   In = theory, is=20 this shape, capable >10 seconds?
 
I hope to use Bob's program to = construct another=20 vertical, but I am confused, about my results.    I know = there=20 are methods for extending the period, but here I am just asking about = the=20 physical results of using     a = spring-supported=20 pendulum constrained to move in a vertical plane.  =20 Perhaps these calculated long periods would only be = possible under=20 the best of conditions, where all factors were = perfect.    I seem=20 to get a period of  around x3  that of the spring hanging = vertical=20 with a mass.    I have tried many different springs and = the=20 result were very similar in achieving only x3.
 
Thanks, Ted
Subject: Re: Verticals From: ChrisAtUpw@....... Date: Sun, 27 Dec 2009 11:34:06 EST In a message dated 27/12/2009, tchannel@............ writes: Hi Folks, I have downloaded Bob McClure's great program SpringCalc.exe. I have put in some numbers and see it calculates very long periods under certain conditions, periods of >20. Hi Ted, The signal amplitude falls off as f^2 below the resonant period of a magnet + coil sensor, so you need quite a large short period signal amplitude to enable you to reconstruct long period signals. A 1 Hz P signal would need to be well over 400 counts to reconstruct the 20 second long period signal. You CAN'T do sensible arithmetic on long period counts of 0 or 1! The digital technique is likely to be much more valuable when you are using a 24 bit ADC and also have very low noise. My question is can long periods like these really be achieved? I have build several models and some working sensors using this approach, but I have never gotten more than about 3x the springs natural frequency. A spring of ..5 second, just hanging vertically, resulted in a sensor of 1.5 seconds. I guess the AS1 is another example. The design of the AS1 is widely used and am I correct that it is operating at about 1.5 seconds? In theory, is this shape, capable >10 seconds? I run an AS1 which has a natural period of 1.5 seconds, but the special amplifier provided compensates this correctly out to 4.5 seconds. Thus I only need an extra gain of x20 to display the 20 second Rayleigh waves at their true amplitude. Yes, digital period extension can work very nicely, so long as the amplifier gain and the signals are large enough. But don't expect to do this with small total count signals. I hope to use Bob's program to construct another vertical, but I am confused, about my results. I know there are methods for extending the period, but here I am just asking about the physical results of using a spring-supported pendulum constrained to move in a vertical plane. Perhaps these calculated long periods would only be possible under the best of conditions, where all factors were perfect. I seem to get a period of around x3 that of the spring hanging vertical with a mass. Try increasing the amplifier gain by x50? This is why I have suggested using a period extending amplifier, rather than by trying to tackle the problem digitally. It is quite easy to get a x10 period extension. Regards, Chris Chapman
In a message dated 27/12/2009, tchannel@............ writes:
Hi Folks,  I have downloaded Bob= McClure's=20 great program SpringCalc.exe. I have put in some numbers and see it calc= ulates=20 very long periods under certain conditions, periods of=20 >20.
Hi Ted,
 
    The signal amplitude falls off as f^2 below= the=20 resonant period of a magnet + coil sensor, so you need quite a large= short=20 period signal amplitude to enable you to reconstruct long period signals.= A 1 Hz=20 P signal would need to be well over 400 counts to reconstruct the 20 secon= d long=20 period signal. 
    You CAN'T do sensible arithmetic on long= =20 period counts of 0 or 1! The digital technique is likely to be much= more=20 valuable when you are using a 24 bit ADC and also have very low noise.
My question is can long periods like th= ese really=20 be achieved? I have build several models and some working sensors using= this=20 approach, but I have never gotten more than about 3x the springs natural= =20 frequency. A spring of .5 second, just hanging vertically, resulted= in a=20 sensor of 1.5 seconds. I guess the AS1 is another example. The desi= gn of=20 the AS1 is widely used and am I correct that it is operating at about 1.= 5=20 seconds? In theory, is this shape, capable >10=20 seconds?
    I run an AS1 which has a natural period of 1.= 5=20 seconds, but the special amplifier provided compensates this correctly out= to=20 4.5 seconds. Thus I only need an extra gain of x20 to display the 20 secon= d=20 Rayleigh waves at their true amplitude. Yes, digital period=20 extension can work very nicely, so long as the amplifier gain and the= =20 signals are large enough. But don't expect to do this with small= total=20 count signals. 
I hope to use Bob's program to construc= t another=20 vertical, but I am confused, about my results. I know there are methods= for=20 extending the period, but here I am just asking about the physical resul= ts of=20 using  a spring-supported pendulum constrained to= move=20 in a vertical plane.   Perhaps these calculated= long=20 periods would only be possible under the best of conditions, where all= factors=20 were perfect. I seem to get a period of around x3 that of the sprin= g=20 hanging vertical with a mass. 
    Try increasing the amplifier gain by x50?
 
    This is why I have suggested using a period= =20 extending amplifier, rather than by trying to tackle the problem digitally= .. It=20 is quite easy to get a x10 period extension.
 
    Regards,
 
    Chris Chapman
Subject: Re: Verticals From: Brett Nordgren brett3nt@............. Date: Sun, 27 Dec 2009 12:01:39 -0500 Hi Ted, At 06:59 AM 12/27/2009 -0700, you wrote: >Hi Folks, I have downloaded Bob McClure's great program >SpringCalc.exe. I have put in some numbers and see it calculates very >long periods under certain conditions, periods of >20. > >My question is can long periods like these really be achieved? In a word, no. The problem is that the support spring strength changes with temperature, enough to mess up any long-period setup. A coil-magnet sensor would be more tolerant of position drift, but maintaining a stable long period will be difficult enough that I believe most would call it impossible. LaCoste & Romberg use a double oven to very precisely control the spring temperature in their gravity meters, and some commercial instruments use exotic low temperature coefficient of elasticity alloys for their springs to reduce the temperature effects (for other reasons). But, in my opinion, the only way to get a stable long period design will be with feedback. Though I will freely admit that I am biased on the subject, if anyone can demonstrate a successful long natural-period (>=20 second) vertical design that doesn't use feedback, I'd very much like to learn how it works. Regards, Brett >I have build several models and some working sensors using this approach, >but I have never gotten more than about 3x the springs natural >frequency. A spring of .5 second, just hanging vertically, resulted in a >sensor of 1.5 seconds. I guess the AS1 is another example. The design >of the AS1 is widely used and am I correct that it is operating at about >1.5 seconds? In theory, is this shape, capable >10 seconds? > >I hope to use Bob's program to construct another vertical, but I am >confused, about my results. I know there are methods for extending the >period, but here I am just asking about the physical results of >using a spring-supported pendulum constrained to move in a vertical >plane. Perhaps these calculated long periods would only be possible >under the best of conditions, where all factors were perfect. I seem to >get a period of around x3 that of the spring hanging vertical with a >mass. I have tried many different springs and the result were very >similar in achieving only x3. > >Thanks, Ted Watch our wiggles http://bnordgren.org/seismo/gif_images.htm or watch some very very good wiggles http://aslwww.cr.usgs.gov/Seismic_Data/telemetry_data/ANMO_24hr.html __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Verticals From: Brett Nordgren brett3nt@............. Date: Sun, 27 Dec 2009 16:30:11 -0500 Hi Ted, At 06:59 AM 12/27/2009 -0700, you wrote: >Hi Folks, I have downloaded Bob McClure's great program >SpringCalc.exe. I have put in some numbers and see it calculates very >long periods under certain conditions, periods of >20. > >My question is can long periods like these really be achieved? Then again, maybe. I took a look at Bob's results and he seems to have been quite successful at lowering the apparent low corner frequency of a vertical by a factor of 8 by using an inverse filter. I would be interested in knowing what the noise of a 2.5second vertical would be in the neighborhood of 20 seconds since, in the process of extending the period, that noise also gets multiplied by 8. If the 20-second noise is low relative to the 20-second ground motions you are expecting, then it should work fine--and Bob's results would tend to bear that out. I'd like to look at the differences between extending the period by using feedback and doing it with an inverse filter. May prove interesting, though I'm convinced that using a feedback design will have some significant advantages. Brett Watch our wiggles http://bnordgren.org/seismo/gif_images.htm or watch some very very good wiggles http://aslwww.cr.usgs.gov/Seismic_Data/telemetry_data/ANMO_24hr.html __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Verticals From: Robert McClure bobmcclure90@......... Date: Sun, 27 Dec 2009 18:03:20 -0500 I completely agree with Brett. Although my SpringCalc.exe program can predict the attainment of long periods, the usual materials for amateur sensor construction make the temperature sensitivity of a long period adjustment too unstable to be practical. My vertical sensor is easily adjusted to have a period of 4.4 seconds. This period is too long to be stable over even minor ambient temperature changes. I have to keep adjusting a movable balance weight over the seasons to keep the pendulum position where I want it, even though the sensor is in the basement where temperature is fairly constant, but colder in winter than summer. I use WQFilter.exe to extend the response to 32 seconds, with additional 32 second corner high pass backfiltering. I agree with Chris that a two-stage Roberts circuit amplifier would perform better under ordinary circumstances. The problem with the Roberts circuit is that you must change circuit components to match the natural period if it changes, and that it cannot compensate for over- or under-damping. Optimal use of WQFilter requires more than minimal amplifier gain to overcome quantization noise in the A/D converter. This is feasible, because the largest signal from a teleseism is usually the L wave, whose amplitude is suppressed by the original short period sensor response, so more gain can be used without overloading the amplifier/A/D. By all means, construct a feedback sensor if you can, but you will likely still have problems with zero drift to cope with. Bob On 12/27/09, Brett Nordgren wrote: > Hi Ted, > > At 06:59 AM 12/27/2009 -0700, you wrote: >>Hi Folks, I have downloaded Bob McClure's great program >>SpringCalc.exe. I have put in some numbers and see it calculates very >>long periods under certain conditions, periods of >20. >> >>My question is can long periods like these really be achieved? > > Then again, maybe. I took a look at Bob's results and he seems to have > been quite successful at lowering the apparent low corner frequency of a > vertical by a factor of 8 by using an inverse filter. I would be > interested in knowing what the noise of a 2.5second vertical would be in > the neighborhood of 20 seconds since, in the process of extending the > period, that noise also gets multiplied by 8. If the 20-second noise is > low relative to the 20-second ground motions you are expecting, then it > should work fine--and Bob's results would tend to bear that out. > > I'd like to look at the differences between extending the period by using > feedback and doing it with an inverse filter. May prove interesting, > though I'm convinced that using a feedback design will have some > significant advantages. > > Brett > > Watch our wiggles > http://bnordgren.org/seismo/gif_images.htm > > or watch some very very good wiggles > http://aslwww.cr.usgs.gov/Seismic_Data/telemetry_data/ANMO_24hr.html > > > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: two-stage Roberts circuit amplifier From: Barry Lotz barry_lotz@............. Date: Sun, 27 Dec 2009 16:42:58 -0800 (PST) Chris I found the abstract and filter diagram on John Lahr's web site. 1) I am no= t sure how the max gain is chosen. Is it based on the difference between th= e actual sensor low frequency corner and the desired low frequency corner g= iven a 40 db /decade dropoff?=A0 2) I assume the two single pole circuits i= dentical 3)=A0 Do the other values in the example circuit remain the same e= xcept as you have commented on? 4) If I want a lower corner frequency of 0.= 03 hz is the "lower turnover frequency (1/2 Pi C1 R2)" =3D 0.015 hz? It is = probably obvious I don't have the full report. Regards Barry http://www.seismicvault.com
Chris
I found the abstract and filter dia= gram on John Lahr's web site. 1) I am not sure how the max gain is chosen. = Is it based on the difference between the actual sensor low frequency corne= r and the desired low frequency corner given a 40 db /decade dropoff? = 2) I assume the two single pole circuits identical 3)  Do the other v= alues in the example circuit remain the same except as you have commented o= n? 4) If I want a lower corner frequency of 0.03 hz is the "lower turnover = frequency (1/2 Pi C1 R2)" =3D 0.015 hz? It is probably obvious I don't have= the full report.

Regards
Barry
http://www.seismicvault.com
Subject: two-stage Roberts circuit amplifier From: Barry Lotz barry_lotz@............. Date: Sun, 27 Dec 2009 18:45:20 -0800 (PST) Chris "=A0 Chris =A0=A0=A0=A0 I found the abstract and filter diagram on John Lahr's web=0As= ite. 1) I am not sure how the=A0 max gain is chosen. Is it based on the=0Ad= ifference between the actual sensor low frequency corner and the=0Adesired = low frequency corner given a 40 db /decade dropoff?=A0 2) I=0Aassume the tw= o single pole circuits identical 3)=A0 Do the other values=0Ain the example= circuit remain the same except as you have commented on?=0A4) If I want a = lower corner frequency of 0.03 hz is the "lower turnover=0Afrequency (1/2 P= i C1 R2)" =3D 0.015 hz? It is probably obvious I don't=0Ahave the full repo= rt." I realize that R3,R7 & R11 are offset resistors. How does one determine the= value of R5 and R8 or does it matter? Regards Barry Subject: Re: two-stage Roberts circuit amplifier From: ChrisAtUpw@....... Date: Sun, 27 Dec 2009 23:48:21 EST In a message dated 28/12/2009, barry_lotz@............. writes: Chris " Chris I found the abstract and filter diagram on John Lahr's web site. 1) I am not sure how the max gain is chosen. Is it based on the difference between the actual sensor low frequency corner and the desired low frequency corner given a 40 db /decade dropoff? Hi Barry, If you wished to get 20 seconds from a 1.5 second pendulum, you would need a total gain at 20 seconds of 178. Each stage will need a gain of 13.3 2) I assume the two single pole circuits identical That is correct 3) Do the other values in the example circuit remain the same except as you have commented on? Correct. 4) If I want a lower corner frequency of 0.03 hz is the "lower turnover frequency (1/2 Pi C1 R2)" = 0.015 hz? It is probably obvious I don't have the full report." See above. correct I realize that R3,R7 & R11 are offset resistors. Correct R5 = R6 = R8 = R9 R10 may be chosen to give any gain that you need. I use a gain of at least x2 per stage How does one determine the value of R5 and R8 or does it matter? I choose values of about 20 K. You don't want to overload your amplifier, but you want to use values which have low noise. 150 K is too much in my opinion. This will give a high maximum gain and noise below 0.03 Hz, so you couple the circuits with a 2 pole high pass filter set at about 0.015 Hz. Regards, Chris Chapman
In a message dated 28/12/2009, barry_lotz@............. writes:
Chris

" = ; Chris
  &nb= sp;  I found the abstract and filter diagram on John Lahr's web=0Asite= .. 1) I am not sure how the  max gain is chosen. Is it based on the=0Ad= ifference between the actual sensor low frequency corner and the=0Adesired = low frequency corner given a 40 db /decade dropoff?  2) I=0Aassume the= two single pole circuits identical 3)  Do the other values=0Ain the e= xample circuit remain the same except as you have commented on?=0A4) If I w= ant a lower corner frequency of 0.03 hz is the "lower turnover=0Afrequency = (1/2 Pi C1 R2)" =3D 0.015 hz? It is probably obvious I don't=0Ahave the ful= l report."

I realize that = R3,R7 & R11 are offset resistors. How does one determine the value of R= 5 and R8 or does it matter?
Regards
Barry

Chris

" =20 Chris
     I found= the=20 abstract and filter diagram on John Lahr's web site. 1) I am not= sure=20 how the  max gain is chosen. Is it based on the difference be= tween=20 the actual sensor low frequency corner and the desired low frequen= cy=20 corner given a 40 db /decade dropoff?
 
Hi Barry,
 
    = ;If you=20 wished to get 20 seconds from a 1.5 second pendulum, you would nee= d a=20 total gain at 20 seconds of 178. Each stage will need a gain of=20 13.3
 
 2) I assume the= two=20 single pole circuits identical
 
    = ;That is=20 correct
 
3)  Do the other= values in=20 the example circuit remain the same except as you have commented= =20 on?
 
    Correct.
 
 4) If I want a lo= wer=20 corner frequency of 0.03 hz is the "lower turnover frequency (1/2= Pi C1=20 R2)" =3D 0.015 hz? It is probably obvious I don't have the full=20 report."
 
See above. =20 correct


I realize that R3,R7= &=20 R11 are offset resistors.
 
Correct
R5 =3D R6 =3D R8 =3D R9
 
R10 may be chosen to give any gain that you need. I use a gai= n of=20 at least x2 per stage
 
How does one determine the value of R5 and R8 or does it=20 matter?
    I choose values of about 20 K.=  =20 You don't want to overload your amplifier, but you want to use values whic= h have=20 low noise. 150 K is too much in my opinion.
 
    This will give a high max= imum=20 gain and noise below 0.03 Hz, so you couple the circuits with a 2 pole hig= h pass=20 filter set at about 0.015 Hz.
 
    Regards,
 
    Chris=20 Chapman  
Subject: Station [GVA] From: "Geoffrey" gmvoeth@........... Date: Sun, 27 Dec 2009 23:39:51 -0700 Hello PSN people; I am trying out an ftp server on my machine and would like you to try it out by logging on and possibly downloading the AVI file that should be there. I am unable to test it myself even tho it seems to be working. IP address 173.16.82.25 User name: PSN Password: PSN123 The AVI file is like 20MB is size and would not upload to youtube (youtube itself seems broken) This file (only one there) shows my station receiver with hoaky audio (wwv + fm radio) playing in the background. Thanks ahead of time for any feedback personal email or otherwise. Regards; geoff __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: two-stage Roberts circuit amplifier From: "Geoffrey" gmvoeth@........... Date: Mon, 28 Dec 2009 01:27:56 -0700 Below resonance at 1Hz for a SPZ Velocity device I recommend no more than 6Dbv per octave (20 per decade) because if you go 40 you get terrible microseismic interferences. So like you give X1250 for everything in a 12 bit system and + 20 Dbv per decade below 1Hz at 20log(vout/vin) So its like X1250 * 10 or x12500 or 20log(12500) overall with a one stage LPF at 0.1 Hz. But only if you use a 12 bit converter with a range of 0 to 4.095 volts. And a sensor of 2.99 volts per inches per second Or so it seems to me based on a lot of playing around. Your sensor here is 1 second free period but the idea is universal. Its interesting to note here you are simply using a generator to act as a receiving antenna for earthly vibrations. Just imagine the terawatts of oil disappearing into the ground with the incessant human activities. Dissapating as entropy and lost literally forever to the depths of space and time. Stand aside Professor CoupDegrass , here i come ! :-) ----- Original Message ----- From: "Barry Lotz" To: Sent: Sunday, December 27, 2009 5:42 PM Subject: two-stage Roberts circuit amplifier Chris I found the abstract and filter diagram on John Lahr's web site. 1) I am not sure how the max gain is chosen. Is it based on the difference between the actual sensor low frequency corner and the desired low frequency corner given a 40 db /decade dropoff? 2) I assume the two single pole circuits identical 3) Do the other values in the example circuit remain the same except as you have commented on? 4) If I want a lower corner frequency of 0.03 hz is the "lower turnover frequency (1/2 Pi C1 R2)" = 0.015 hz? It is probably obvious I don't have the full report. Regards Barry http://www.seismicvault.com __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: two-stage Roberts circuit amplifier From: ChrisAtUpw@....... Date: Mon, 28 Dec 2009 07:11:56 EST In a message dated 28/12/2009, gmvoeth@........... writes: Below resonance at 1Hz for a SPZ Velocity device I recommend no more than 6dBv per octave (20 per decade) because if you go 40 you get terrible microseismic interferences. Hi Geoff, I don't understand the rest of your Email. Normal coil + magnet devices all give a roll off at 40 dB per decade, which needs to be compensated if you want to detect longer period seismic signals. YOU DON'T HAVE ANY CHOICE! However, you can extend the period of a geophone or an AS1 type vertical sensor by x10 without running into noise problems. So a seismometer with a natural period of 1.5 seconds can fairly easily be extended to 20 seconds. This enables it to cover most of the 'normal' seismic band quite OK for amateur purposes. I use this system and it works. I simply filter out the microseisms on the drumplot display in Amaseis, but they are normal in size as on a broadband sensor. Regards, Chris Chapman
In a message dated 28/12/2009, gmvoeth@........... writes:
Below=20 resonance at 1Hz for a SPZ Velocity device
I recommend no more than= 6dBv=20 per octave (20 per decade)
because if you go 40 you get terrible=20 microseismic interferences.
Hi Geoff,
 
    I don't understand the rest of your Email.
 
    Normal coil + magnet devices all give a roll= off at=20 40 dB per decade, which needs to be compensated if you want to detect long= er=20 period seismic signals. YOU DON'T HAVE ANY CHOICE!
 
    However, you can extend the period of a geoph= one or=20 an AS1 type vertical sensor by x10 without running into noise problems. So= =20 a seismometer with a natural period of 1.5 seconds can fairly easily= be=20 extended to 20 seconds. This enables it to cover most of the 'normal'= =20 seismic band quite OK for amateur purposes.
 
    I use this system and it works. I simply= =20 filter out the microseisms on the drumplot display in Amaseis, but they ar= e=20 normal in size as on a broadband sensor.
 
    Regards,
 
    Chris Chapman
 
 
Subject: Downloades from the ftp server I created for PSN folks From: "Geoffrey" gmvoeth@........... Date: Mon, 28 Dec 2009 14:01:46 -0700 Hello PSN; I would like to let you know that everything within the scratch folder is OK for you to download. I have been watching the last several hours the progress of several downloads and come to the conclusion there is some kind of interference with connections that cross the USA border. It may not be possible for Non-USA people to download these files in a timely fashion. But do not let you stop trying because like always I could be wrong. I will post just about everything related to PSN or Seismology that I do here and it is not intended for the general public but only PSN peoples who I believe are truly interested in seismology/geophysics/programming/instrumentation. I will not be up 100% of the time. Most likely Randomly between 24:00 and 12:00 UTC when the net is least used here. FTP SERVER IP: 173.016.082.025 ( NOT STATIC can change periodically by the ISP ) FTP UID: PSN FTP PASS: PSN123 FTP PORTS: 1024 to 65535 are open with passive ftp enabled. FTP CHANNEL: 20/21 I think are standard for FTP It is for download only and not intended to let people do P2P ( peer to peer ) stuff. Don't laugh too hard since this how I have chosen to waste my life. You guys are much more serious armatures than myself. Be happy if you get better than 60KB/SEC downloads because EUROPE was getting like 1K or less for reasons not fully understood. The limits are not my machine since everything on the B drive is ramdisk ( very fast ). The connection is A Gbit modem. The limits has to be ISP or Backbone related. Its all just to show you what I do here at GVA the best I can. Question; Not sure what official armature group [GVA] is a part of to put into the PSN4 file header, possibly someone can tell me in a personal email. I will change the header from "123456" to reflect this. A USGS expert person named Bruce Presgrave assigned me this designation. But all I know is [GVA] and not any parent organization. Regards, geoff __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Downloades from the ftp server I created for PSN folks From: sismos sismos@.............. Date: Mon, 28 Dec 2009 22:17:58 +0000 Hi Geoff, I downloaded the AVI file just minutes after you posted the link. I live in Panama. It only took a few minutes, quite fast actually. I have to admit that the video was strange and looked more like a home canning operation than a seismic station. I say this kindly because my station look more like rats nests than seismic stations. What is in all the jars? I really like reading your post. Saludos, Angel On Mon, 2009-12-28 at 14:01 -0700, Geoffrey wrote: > Hello PSN; > > I would like to let you know that everything within the scratch folder > is OK for you to download. > > I have been watching the last several hours the progress > of several downloads and come to the conclusion > there is some kind of interference with connections > that cross the USA border. > > It may not be possible for Non-USA people to > download these files in a timely fashion. > > But do not let you stop trying because like > always I could be wrong. > > I will post just about everything related to > PSN or Seismology that I do here and it is not > intended for the general public but only > PSN peoples who I believe are truly > interested in seismology/geophysics/programming/instrumentation. > > I will not be up 100% of the time. > > Most likely Randomly between 24:00 and 12:00 UTC > when the net is least used here. > > FTP SERVER IP: 173.016.082.025 ( NOT STATIC can change periodically by the ISP ) > FTP UID: PSN > FTP PASS: PSN123 > FTP PORTS: 1024 to 65535 are open with passive ftp enabled. > FTP CHANNEL: 20/21 I think are standard for FTP > > It is for download only and not intended > to let people do P2P ( peer to peer ) stuff. > > Don't laugh too hard since this how I have chosen to waste my life. > > You guys are much more serious armatures than myself. > > Be happy if you get better than 60KB/SEC downloads > because EUROPE was getting like 1K or less for reasons > not fully understood. > The limits are not my machine since everything > on the B drive is ramdisk ( very fast ). > The connection is A Gbit modem. > The limits has to be ISP or Backbone related. > > Its all just to show you what I do here at GVA the best I can. > > Question; > Not sure what official armature group [GVA] is a part of > to put into the PSN4 file header, possibly > someone can tell me in a personal email. > I will change the header from "123456" to reflect this. > > A USGS expert person named Bruce Presgrave assigned me this designation. > But all I know is [GVA] and not any parent organization. > > Regards, > geoff > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Downloades from the ftp server I created for PSN folks From: "Geoffrey" gmvoeth@........... Date: Mon, 28 Dec 2009 16:56:38 -0700 Hello sismos; Some folks like from europe are having an impossible time downloading, its so slow and random for them. I played with the ports and it would get them going a bit but they stall again and again. So i just opened up all the ports. The can on the left near the input cable is actually two cheap metal pans held together with big paper clips contains two things I found them in the dollar store. a. a manual tester thing with alligator clips to test input from the geophone as well as timing b. the tone decoder from the sw radio with wwv audio used to synchronize the ring counter ( fancier than it sounds ) The can which it feeds is that timer to be set with wwv. The timer is a custom kit from an austrailian company called DIY kit 141 I think. The can on the right next to the computer contains the A/D converter I put these in cans because they are with their oscillators terrible generators of RFI. The strip in the middle is the amplifier, equalizer, antialize filter. This is feeding the 12 bit A/D converter. The two identical circuits are +/- 3.00V regulated power supplies fed by the 12vDC modules connected to the UPS power supply. Hopefully but possibly not the UPS should keep the recorder going if the power fails for a single record 45 minutes long. The sound was all from my SW radio first listening to WWV then with the BFO on then with FM selected. I made the MOV file with a Kodak digital camera then combined the video with sound using a freeby cinverter to make the AVI takes a bit of messing around to make it all work. I have one remaining trouble Im unable to solve and that is high static electricity and RFI from police or fire or ??? Radios in the area disturbing the serial communications causing the program to develope a runtime error stopping it cold in its tracks and requires me to reBOOT the computer. I am never sure what stops it cold but occassionally this happens. Possibly building the thing right would solve that problem. It is only a prototype suitable for lab environment and not the public. It is not properly constructed due to opportunity costs I would incurr to make it be right. Hey, its only a hobby to keep me out of trouble. Its all old technology. From the public domain. I will someday make a video with all the covers off or put the scematics into a folder for you to download. Everything is on an aluminum sheet and surrounded by salt water to moderate the temperature changes. Everything is designed for common mode over differential noises of whatever kind. Proper grounding/shielding is one of the most troublesome things to conquer. Hope it answers most of your questions ?? Regards; geoff ----- Original Message ----- From: "sismos" To: Sent: Monday, December 28, 2009 3:17 PM Subject: Re: Downloades from the ftp server I created for PSN folks > Hi Geoff, > > I downloaded the AVI file just minutes after you posted the link. I > live in Panama. It only took a few minutes, quite fast actually. > > I have to admit that the video was strange and looked more like a home > canning operation than a seismic station. I say this kindly because my > station look more like rats nests than seismic stations. What is in all > the jars? > > I really like reading your post. > > Saludos, > > Angel > > > On Mon, 2009-12-28 at 14:01 -0700, Geoffrey wrote: >> Hello PSN; >> >> I would like to let you know that everything within the scratch folder >> is OK for you to download. >> >> I have been watching the last several hours the progress >> of several downloads and come to the conclusion >> there is some kind of interference with connections >> that cross the USA border. >> >> It may not be possible for Non-USA people to >> download these files in a timely fashion. >> >> But do not let you stop trying because like >> always I could be wrong. >> >> I will post just about everything related to >> PSN or Seismology that I do here and it is not >> intended for the general public but only >> PSN peoples who I believe are truly >> interested in seismology/geophysics/programming/instrumentation. >> >> I will not be up 100% of the time. >> >> Most likely Randomly between 24:00 and 12:00 UTC >> when the net is least used here. >> >> FTP SERVER IP: 173.016.082.025 ( NOT STATIC can change periodically by the ISP ) >> FTP UID: PSN >> FTP PASS: PSN123 >> FTP PORTS: 1024 to 65535 are open with passive ftp enabled. >> FTP CHANNEL: 20/21 I think are standard for FTP >> >> It is for download only and not intended >> to let people do P2P ( peer to peer ) stuff. >> >> Don't laugh too hard since this how I have chosen to waste my life. >> >> You guys are much more serious armatures than myself. >> >> Be happy if you get better than 60KB/SEC downloads >> because EUROPE was getting like 1K or less for reasons >> not fully understood. >> The limits are not my machine since everything >> on the B drive is ramdisk ( very fast ). >> The connection is A Gbit modem. >> The limits has to be ISP or Backbone related. >> >> Its all just to show you what I do here at GVA the best I can. >> >> Question; >> Not sure what official armature group [GVA] is a part of >> to put into the PSN4 file header, possibly >> someone can tell me in a personal email. >> I will change the header from "123456" to reflect this. >> >> A USGS expert person named Bruce Presgrave assigned me this designation. >> But all I know is [GVA] and not any parent organization. >> >> Regards, >> geoff >> __________________________________________________________ >> >> Public Seismic Network Mailing List (PSN-L) >> >> To leave this list email PSN-L-REQUEST@.............. with >> the body of the message (first line only): unsubscribe >> See http://www.seismicnet.com/maillist.html for more information. >> > > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Downloades from the ftp server I created for PSN folks From: =?ISO-8859-1?Q?J=F3n_Fr=EDmann?= jonfr@......... Date: Mon, 28 Dec 2009 23:59:50 +0000 Hi Geoffrey, There is no reason for you to open up all the ports on your ftp server, doing to resaults in a securty risk. This might be a issue with the ftp server rather then your computer. Check the software first, then the connection. Regards, J=F3n Fr=EDmann. On m=E1n, 2009-12-28 at 16:56 -0700, Geoffrey wrote: > Hello sismos; >=20 > Some folks like from europe are having an impossible time > downloading, its so slow and random for them. >=20 > I played with the ports and it would get them > going a bit but they stall again and again. > So i just opened up all the ports. >=20 > The can on the left near the input cable > is actually two cheap metal pans held together > with big paper clips contains two things > I found them in the dollar store. >=20 > a. a manual tester thing with alligator clips > to test input from the geophone as well as timing > b. the tone decoder from the sw radio with wwv audio > used to synchronize the ring counter ( fancier than it sounds ) > The can which it feeds is that timer to be set with wwv. > The timer is a custom kit from an austrailian company called DIY > kit 141 I think. >=20 > The can on the right next to the computer contains the A/D converter >=20 > I put these in cans because they are with their oscillators > terrible generators of RFI. >=20 > The strip in the middle is the amplifier, equalizer, antialize filter. > This is feeding the 12 bit A/D converter. >=20 >=20 > The two identical circuits are +/- 3.00V regulated power supplies fed by > the 12vDC modules connected to the UPS power supply. >=20 > Hopefully but possibly not the UPS should keep the > recorder going if the power fails for a single record 45 > minutes long. >=20 > The sound was all from my SW radio first listening to WWV > then with the BFO on then with FM selected. >=20 > I made the MOV file with a Kodak digital camera then combined the > video with sound using a freeby cinverter to make the AVI > takes a bit of messing around to make it all work. >=20 > I have one remaining trouble Im unable to solve > and that is high static electricity and > RFI from police or fire or ??? Radios in the area > disturbing the serial communications causing > the program to develope a runtime error stopping > it cold in its tracks and requires me to reBOOT > the computer. > I am never sure what stops it cold but occassionally > this happens. Possibly building the thing right > would solve that problem. >=20 > It is only a prototype suitable for lab > environment and not the public. >=20 > It is not properly constructed due to > opportunity costs I would incurr to make > it be right. >=20 > Hey, its only a hobby to keep me out of trouble. > Its all old technology. From the public domain. >=20 > I will someday make a video with all the covers off > or put the scematics into a folder for you to download. >=20 > Everything is on an aluminum sheet and surrounded > by salt water to moderate the temperature changes. >=20 > Everything is designed for common mode over differential noises > of whatever kind. >=20 > Proper grounding/shielding is one of the most troublesome things > to conquer. >=20 > Hope it answers most of your questions ?? >=20 > Regards; > geoff >=20 >=20 > ----- Original Message -----=20 > From: "sismos" > To: > Sent: Monday, December 28, 2009 3:17 PM > Subject: Re: Downloades from the ftp server I created for PSN folks >=20 >=20 > > Hi Geoff, > >=20 > > I downloaded the AVI file just minutes after you posted the link. I > > live in Panama. It only took a few minutes, quite fast actually. > >=20 > > I have to admit that the video was strange and looked more like a home > > canning operation than a seismic station. I say this kindly because my > > station look more like rats nests than seismic stations. What is in all > > the jars? > >=20 > > I really like reading your post. > >=20 > > Saludos, > >=20 > > Angel > >=20 > >=20 > > On Mon, 2009-12-28 at 14:01 -0700, Geoffrey wrote: > >> Hello PSN; > >>=20 > >> I would like to let you know that everything within the scratch folder > >> is OK for you to download. > >>=20 > >> I have been watching the last several hours the progress > >> of several downloads and come to the conclusion > >> there is some kind of interference with connections > >> that cross the USA border. > >>=20 > >> It may not be possible for Non-USA people to > >> download these files in a timely fashion. > >>=20 > >> But do not let you stop trying because like > >> always I could be wrong. > >>=20 > >> I will post just about everything related to > >> PSN or Seismology that I do here and it is not > >> intended for the general public but only > >> PSN peoples who I believe are truly > >> interested in seismology/geophysics/programming/instrumentation. > >>=20 > >> I will not be up 100% of the time. > >>=20 > >> Most likely Randomly between 24:00 and 12:00 UTC > >> when the net is least used here. > >> =20 > >> FTP SERVER IP: 173.016.082.025 ( NOT STATIC can change periodically b= y the ISP ) > >> FTP UID: PSN > >> FTP PASS: PSN123 > >> FTP PORTS: 1024 to 65535 are open with passive ftp enabled. > >> FTP CHANNEL: 20/21 I think are standard for FTP > >>=20 > >> It is for download only and not intended > >> to let people do P2P ( peer to peer ) stuff. > >>=20 > >> Don't laugh too hard since this how I have chosen to waste my life. > >>=20 > >> You guys are much more serious armatures than myself. > >>=20 > >> Be happy if you get better than 60KB/SEC downloads > >> because EUROPE was getting like 1K or less for reasons > >> not fully understood. > >> The limits are not my machine since everything > >> on the B drive is ramdisk ( very fast ). > >> The connection is A Gbit modem. > >> The limits has to be ISP or Backbone related. > >>=20 > >> Its all just to show you what I do here at GVA the best I can. > >>=20 > >> Question; > >> Not sure what official armature group [GVA] is a part of > >> to put into the PSN4 file header, possibly > >> someone can tell me in a personal email. > >> I will change the header from "123456" to reflect this. > >>=20 > >> A USGS expert person named Bruce Presgrave assigned me this designatio= n. > >> But all I know is [GVA] and not any parent organization. > >>=20 > >> Regards, > >> geoff > >> __________________________________________________________ > >>=20 > >> Public Seismic Network Mailing List (PSN-L) > >>=20 > >> To leave this list email PSN-L-REQUEST@.............. with=20 > >> the body of the message (first line only): unsubscribe > >> See http://www.seismicnet.com/maillist.html for more information. > >>=20 > >=20 > > __________________________________________________________ > >=20 > > Public Seismic Network Mailing List (PSN-L) > >=20 > > To leave this list email PSN-L-REQUEST@.............. with=20 > > the body of the message (first line only): unsubscribe > > See http://www.seismicnet.com/maillist.html for more information. > > > __________________________________________________________ >=20 > Public Seismic Network Mailing List (PSN-L) >=20 > To leave this list email PSN-L-REQUEST@.............. with=20 > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: two-stage Roberts circuit amplifier From: Barry Lotz barry_lotz@............. Date: Mon, 28 Dec 2009 18:24:06 -0800 (PST) Chris It took a little clearing of the cobwebs to duplicate the gain you got but = I did. Thanks. Regards Barry http://www.seismicvault.com --- On Sun, 12/27/09, ChrisAtUpw@....... wrote: From: ChrisAtUpw@....... Subject: Re: two-stage Roberts circuit amplifier To: psn-l@.............. Date: Sunday, December 27, 2009, 8:48 PM =0A=0A =0A=0A=0AIn a message dated 28/12/2009, barry_lotz@............. wri= tes:=0A=0A =0A =0A =0A =0A =20 =0A =A0=0A Hi Barry,=0A =A0=0A =A0=A0=A0=A0If y= ou =0A wished to get 20 seconds from a 1.5 second pendulum, you woul= d need a =0A total gain at 20 seconds of 178. Each stage will need a= gain of =0A 13.3=0A =A0 =A0=A0=A0=A0Regards,=0A=A0=0A=A0=A0=A0=A0Chris =0AChapman=A0=A0
Chris
It took a little clearing of the cob= webs to duplicate the gain you got but I did. Thanks.

Regards
Bar= ry
= http://www.seismicvault.com

--- On Sun, 12/27/09, ChrisAtU= pw@....... <ChrisAtUpw@.......> wrote:

From: ChrisAtUpw@....... <ChrisAtUpw@.......>
Subject= : Re: two-stage Roberts circuit amplifier
To: psn-l@..............
Da= te: Sunday, December 27, 2009, 8:48 PM

=0A= =0A =0A=0A
=0A
In a message dated 28/12/2009, barry_lotz@............. = writes:
=0A
=0A =0A =0A =0A
=0A

=0A
&nb= sp;
=0A
Hi Barry,=
=0A
 
=0A
&nbs= p;   If you =0A wished to get 20 seconds from a 1.5 s= econd pendulum, you would need a =0A total gain at 20 seconds of 178= .. Each stage will need a gain of =0A 13.3
=0A  

 &nbs= p;  Regards,
=0A
 =0A
    Chris =0AChapman =  
Subject: Sensor noise From: Barry Lotz barry_lotz@............. Date: Mon, 28 Dec 2009 21:12:21 -0800 (PST) All I have successfully used a running fft to sense signal frequency component = changes and used this as a trigger mechanism for an event. Could one use th= e=A0 ( I guess you call it ) power spectrum of the signal just before and d= uring the event to remove the noise? I guess you would have to use the same= time window so the frequencies would compare. Could it be a simple subtrac= tion of the "before" from the "during"? This would assume that the backgrou= nd noise didn't change in the period during an event. This could be better = than trying to shape a multi pole filter to eliminate the noise. I have fou= nd that often a portion of the event signal is in the same frequency range = as the noise.=A0=20 Regards Barry http://www.seismicvault.com
All
I have succes= sfully used a running fft to sense signal frequency component changes and u= sed this as a trigger mechanism for an event. Could one use the  ( I g= uess you call it ) power spectrum of the signal just before and during the = event to remove the noise? I guess you would have to use the same time wind= ow so the frequencies would compare. Could it be a simple subtraction of th= e "before" from the "during"? This would assume that the background noise d= idn't change in the period during an event. This could be better than tryin= g to shape a multi pole filter to eliminate the noise. I have found that of= ten a portion of the event signal is in the same frequency range as the noi= se. 

Regards
Barry
http://www.seismicvault.com
Subject: Re: two-stage Roberts circuit amplifier From: "Geoffrey" gmvoeth@........... Date: Tue, 29 Dec 2009 01:33:26 -0700 Wellll, actually just build your stages adjustable then you can tweak whatever until you see the grass. Thats all you need just give it what it needs till you see the grass. Once you see that grass you should be doing the best you can. ----- Original Message ----- From: "Barry Lotz" To: Sent: Monday, December 28, 2009 7:24 PM Subject: Re: two-stage Roberts circuit amplifier Chris It took a little clearing of the cobwebs to duplicate the gain you got but I did. Thanks. Regards Barry http://www.seismicvault.com --- On Sun, 12/27/09, ChrisAtUpw@....... wrote: From: ChrisAtUpw@....... Subject: Re: two-stage Roberts circuit amplifier To: psn-l@.............. Date: Sunday, December 27, 2009, 8:48 PM In a message dated 28/12/2009, barry_lotz@............. writes: Hi Barry, If you wished to get 20 seconds from a 1.5 second pendulum, you would need a total gain at 20 seconds of 178. Each stage will need a gain of 13.3 Regards, Chris Chapman __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Sensor noise From: "Geoffrey" gmvoeth@........... Date: Tue, 29 Dec 2009 01:46:03 -0700 You can do a similar thing with the sound program AUDACITY but you find it will take out everything even your signal if not careful. Narrow band is the best way to beat noise. Look only in the area of the spectrum that contains the signals you want. CLIP a piece of noise then remove that same noise over the entire data. It removes best at the very place it was clipped from and sporadic everywhere else. It might be good to to have two seperate amplifiers one for regional and one for teleseismic they overlap but are not identical. If noise is at the same freq even if alised it can not be removed as far as I know without affecting your signal too. An fft might be best at seeing things alone but it takes a span of time to see such a signal so your time resolution/precision is possibly destroyed. The original signal is best without too much filtering. Just try and get the noise low and uniform and the signal should stick out like a sore thumb even if it does not look pretty like the scientist want. ----- Original Message ----- From: "Barry Lotz" To: Sent: Monday, December 28, 2009 10:12 PM Subject: Sensor noise All I have successfully used a running fft to sense signal frequency component changes and used this as a trigger mechanism for an event. Could one use the ( I guess you call it ) power spectrum of the signal just before and during the event to remove the noise? I guess you would have to use the same time window so the frequencies would compare. Could it be a simple subtraction of the "before" from the "during"? This would assume that the background noise didn't change in the period during an event. This could be better than trying to shape a multi pole filter to eliminate the noise. I have found that often a portion of the event signal is in the same frequency range as the noise. Regards Barry http://www.seismicvault.com __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Downloades from the ftp server I created for PSN folks From: "Geoffrey" gmvoeth@........... Date: Tue, 29 Dec 2009 01:52:01 -0700 MORTON SALT DISSOLVED IN TAPWATER. Thermal mass for thermal momentum. RFI absorber hopefully. If the human body is resistant to RFI then so should salt water be. I think ??? You got to make all the various changes be as common mode as possible to everything at the same time or it shows as unwanted noise. Even common mode can if its big enough. Common mode is like you shake the whole person instead of only their hand. ----- Original Message ----- From: "sismos" To: Sent: Monday, December 28, 2009 3:17 PM Subject: Re: Downloades from the ftp server I created for PSN folks > Hi Geoff, > > I downloaded the AVI file just minutes after you posted the link. I > live in Panama. It only took a few minutes, quite fast actually. > > I have to admit that the video was strange and looked more like a home > canning operation than a seismic station. I say this kindly because my > station look more like rats nests than seismic stations. What is in all > the jars? > > I really like reading your post. > > Saludos, > > Angel > > > On Mon, 2009-12-28 at 14:01 -0700, Geoffrey wrote: >> Hello PSN; >> >> I would like to let you know that everything within the scratch folder >> is OK for you to download. >> >> I have been watching the last several hours the progress >> of several downloads and come to the conclusion >> there is some kind of interference with connections >> that cross the USA border. >> >> It may not be possible for Non-USA people to >> download these files in a timely fashion. >> >> But do not let you stop trying because like >> always I could be wrong. >> >> I will post just about everything related to >> PSN or Seismology that I do here and it is not >> intended for the general public but only >> PSN peoples who I believe are truly >> interested in seismology/geophysics/programming/instrumentation. >> >> I will not be up 100% of the time. >> >> Most likely Randomly between 24:00 and 12:00 UTC >> when the net is least used here. >> >> FTP SERVER IP: 173.016.082.025 ( NOT STATIC can change periodically by the ISP ) >> FTP UID: PSN >> FTP PASS: PSN123 >> FTP PORTS: 1024 to 65535 are open with passive ftp enabled. >> FTP CHANNEL: 20/21 I think are standard for FTP >> >> It is for download only and not intended >> to let people do P2P ( peer to peer ) stuff. >> >> Don't laugh too hard since this how I have chosen to waste my life. >> >> You guys are much more serious armatures than myself. >> >> Be happy if you get better than 60KB/SEC downloads >> because EUROPE was getting like 1K or less for reasons >> not fully understood. >> The limits are not my machine since everything >> on the B drive is ramdisk ( very fast ). >> The connection is A Gbit modem. >> The limits has to be ISP or Backbone related. >> >> Its all just to show you what I do here at GVA the best I can. >> >> Question; >> Not sure what official armature group [GVA] is a part of >> to put into the PSN4 file header, possibly >> someone can tell me in a personal email. >> I will change the header from "123456" to reflect this. >> >> A USGS expert person named Bruce Presgrave assigned me this designation. >> But all I know is [GVA] and not any parent organization. >> >> Regards, >> geoff >> __________________________________________________________ >> >> Public Seismic Network Mailing List (PSN-L) >> >> To leave this list email PSN-L-REQUEST@.............. with >> the body of the message (first line only): unsubscribe >> See http://www.seismicnet.com/maillist.html for more information. >> > > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Downloades from the ftp server I created for PSN folks From: ian ian@........... Date: Tue, 29 Dec 2009 11:01:17 +0000 for videos, could I suggest something like vimeo.com. You won't need to serve the ftp requests and the video will be compressed (by vimeo) so will download quicker. Just a thought. Ian Geoffrey wrote: > MORTON SALT DISSOLVED IN TAPWATER. > Thermal mass for thermal momentum. > RFI absorber hopefully. > If the human body is resistant to RFI > then so should salt water be. I think ??? > You got to make all the various changes be > as common mode as possible to everything > at the same time or it shows as unwanted noise. > Even common mode can if its big enough. > > Common mode is like you shake the whole person > instead of only their hand. > > > ----- Original Message ----- From: "sismos" > To: > Sent: Monday, December 28, 2009 3:17 PM > Subject: Re: Downloades from the ftp server I created for PSN folks > > >> Hi Geoff, >> >> I downloaded the AVI file just minutes after you posted the link. I >> live in Panama. It only took a few minutes, quite fast actually. >> >> I have to admit that the video was strange and looked more like a home >> canning operation than a seismic station. I say this kindly because my >> station look more like rats nests than seismic stations. What is in all >> the jars? >> >> I really like reading your post. >> >> Saludos, >> >> Angel >> >> >> On Mon, 2009-12-28 at 14:01 -0700, Geoffrey wrote: >>> Hello PSN; >>> >>> I would like to let you know that everything within the scratch folder >>> is OK for you to download. >>> >>> I have been watching the last several hours the progress >>> of several downloads and come to the conclusion >>> there is some kind of interference with connections >>> that cross the USA border. >>> >>> It may not be possible for Non-USA people to >>> download these files in a timely fashion. >>> >>> But do not let you stop trying because like >>> always I could be wrong. >>> >>> I will post just about everything related to >>> PSN or Seismology that I do here and it is not >>> intended for the general public but only >>> PSN peoples who I believe are truly >>> interested in seismology/geophysics/programming/instrumentation. >>> >>> I will not be up 100% of the time. >>> >>> Most likely Randomly between 24:00 and 12:00 UTC >>> when the net is least used here. >>> >>> FTP SERVER IP: 173.016.082.025 ( NOT STATIC can change periodically >>> by the ISP ) >>> FTP UID: PSN >>> FTP PASS: PSN123 >>> FTP PORTS: 1024 to 65535 are open with passive ftp enabled. >>> FTP CHANNEL: 20/21 I think are standard for FTP >>> >>> It is for download only and not intended >>> to let people do P2P ( peer to peer ) stuff. >>> >>> Don't laugh too hard since this how I have chosen to waste my life. >>> >>> You guys are much more serious armatures than myself. >>> >>> Be happy if you get better than 60KB/SEC downloads >>> because EUROPE was getting like 1K or less for reasons >>> not fully understood. >>> The limits are not my machine since everything >>> on the B drive is ramdisk ( very fast ). >>> The connection is A Gbit modem. >>> The limits has to be ISP or Backbone related. >>> >>> Its all just to show you what I do here at GVA the best I can. >>> >>> Question; >>> Not sure what official armature group [GVA] is a part of >>> to put into the PSN4 file header, possibly >>> someone can tell me in a personal email. >>> I will change the header from "123456" to reflect this. >>> >>> A USGS expert person named Bruce Presgrave assigned me this >>> designation. >>> But all I know is [GVA] and not any parent organization. >>> >>> Regards, >>> geoff >>> __________________________________________________________ >>> >>> Public Seismic Network Mailing List (PSN-L) >>> >>> To leave this list email PSN-L-REQUEST@.............. with the body >>> of the message (first line only): unsubscribe >>> See http://www.seismicnet.com/maillist.html for more information. >>> >> >> __________________________________________________________ >> >> Public Seismic Network Mailing List (PSN-L) >> >> To leave this list email PSN-L-REQUEST@.............. with the body >> of the message (first line only): unsubscribe >> See http://www.seismicnet.com/maillist.html for more information. >> > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with the body of > the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Sensor noise From: Brett Nordgren brett3nt@............. Date: Tue, 29 Dec 2009 08:26:10 -0500 Hi Barry, Good try but, unfortunately, I don't think so. At 09:12 PM 12/28/2009 -0800, you wrote: >All >I have successfully used a running fft to sense signal frequency component >changes and used this as a trigger mechanism for an event. Could one use >the ( I guess you call it ) power spectrum of the signal just before and >during the event to remove the noise? I guess you would have to use the >same time window so the frequencies would compare. Could it be a simple >subtraction of the "before" from the "during"? This would assume that the >background noise didn't change in the period during an event. By its very nature, noise *is* changing....randomly. Its overall spectrum may remain constant, but that is created by time-averaging a noise voltage which is constantly varying in an unpredictable way. A possible working definition of noise would be 'that part of a signal which can not be predicted and subtracted out'. >This could be better than trying to shape a multi pole filter to eliminate >the noise. I have found that often a portion of the event signal is in the >same frequency range as the noise. To really reduce the noise to a minimum you have to have a quiet site and build a quiet seismometer. For the noise that remains, filtering eliminates both noise and earthquake signals. Hopefully, the worst noise will be at frequencies that are not required to properly see the quakes. For the FBV we often filter out anything above 0.08 Hz, as that's where you find a lot of the noise, while much of the motion from distant quakes will be below that frequency. ANMO in Albuquerque go even further with their Web display and filter at something like 0.05 Hz, and they sometimes don't show the higher-frequency quakes very clearly that we can see fine. Regards, Brett Watch our wiggles http://bnordgren.org/seismo/gif_images.htm or watch some very very good wiggles http://aslwww.cr.usgs.gov/Seismic_Data/telemetry_data/ANMO_24hr.html __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Sensor noise From: Barry Lotz barry_lotz@............. Date: Tue, 29 Dec 2009 05:28:02 -0800 (PST) Geoffrey I use audacity for recording. I like it a lot. I'll look in to it. The problem I see now with the fft procedure I described is phase angle. The phase angle of the particular frequency in the noise doesn't have to be at the same phase angle as that frequency in the event. Therefore one can't just subtract one from the other.--- Oh well. Regards Barry http://www.seismicvault.com --- On Tue, 12/29/09, Geoffrey wrote: From: Geoffrey Subject: Re: Sensor noise To: psn-l@.............. Date: Tuesday, December 29, 2009, 12:46 AM You can do a similar thing with the sound program AUDACITY but you find it will take out everything even your signal if not careful. Narrow band is the best way to beat noise. Look only in the area of the spectrum that contains the signals you want. CLIP a piece of noise then remove that same noise over the entire data. It removes best at the very place it was clipped from and sporadic everywhere else. It might be good to to have two seperate amplifiers one for regional and one for teleseismic they overlap but are not identical. If noise is at the same freq even if alised it can not be removed as far as I know without affecting your signal too. An fft might be best at seeing things alone but it takes a span of time to see such a signal so your time resolution/precision is possibly destroyed. The original signal is best without too much filtering. Just try and get the noise low and uniform and the signal should stick out like a sore thumb even if it does not look pretty like the scientist want. ----- Original Message ----- From: "Barry Lotz" To: Sent: Monday, December 28, 2009 10:12 PM Subject: Sensor noise All I have successfully used a running fft to sense signal frequency component changes and used this as a trigger mechanism for an event. Could one use the ( I guess you call it ) power spectrum of the signal just before and during the event to remove the noise? I guess you would have to use the same time window so the frequencies would compare. Could it be a simple subtraction of the "before" from the "during"? This would assume that the background noise didn't change in the period during an event. This could be better than trying to shape a multi pole filter to eliminate the noise. I have found that often a portion of the event signal is in the same frequency range as the noise. Regards Barry http://www.seismicvault.com __________________________________________________________ Public Seismic Network Mailing List (PSN-L)
Geoffrey
I use audacity for recording. I like it a lot. I'll look in to it. The problem I see now with the fft procedure I described is phase angle. The phase angle of the particular frequency in the noise doesn't have to be at the same phase angle as that frequency in the event. Therefore one can't just subtract one from the other.--- Oh well.

Regards
Barry
http://www.seismicvault.com

--- On Tue, 12/29/09, Geoffrey <gmvoeth@...........> wrote:

From: Geoffrey <gmvoeth@...........>
Subject: Re: Sensor noise
To: psn-l@..............
Date: Tuesday, December 29, 2009, 12:46 AM

You can do a similar thing with the sound
program AUDACITY but you find it will
take out everything even your signal
if not careful.
Narrow band is the best way to beat noise.
Look only in the area of the spectrum
that contains the signals you want.

CLIP a piece of noise then remove that same
noise over the entire data.
It removes best at the very place
it was clipped from and sporadic
everywhere else.

It might be good to to have two seperate amplifiers
one for regional and one for teleseismic
they overlap but are not identical.
If noise is at the same freq even if alised it can
not be removed as far as I know without
affecting your signal too.

An fft might be best at seeing things alone
but it takes a span of time to see such
a signal so your time resolution/precision
is possibly destroyed.

The original signal is best without too much
filtering.

Just try and get the noise low and uniform
and the signal should stick out like
a sore thumb even if it does not
look pretty like the scientist want.


----- Original Message ----- From: "Barry Lotz" <barry_lotz@.............>
To: <psn-l@..............>
Sent: Monday, December 28, 2009 10:12 PM
Subject: Sensor noise


All
I have successfully used a running fft to sense signal frequency component changes and used this as a trigger mechanism for an event. Could one use the ( I guess you call it ) power spectrum of the signal just before and during the event to remove the noise? I guess you would have to use the same time window so the frequencies would compare. Could it be a simple subtraction of the "before" from the "during"? This would assume that the background noise didn't change in the period during an event. This could be better than trying to shape a multi pole filter to eliminate the noise. I have found that often a portion of the event signal is in the same frequency range as the noise.

Regards
Barry
http://www.seismicvault.com
__________________________________________________________

Public Seismic Network Mailing List (PSN-L)

To leave this list email PSN-L-REQUEST@SEISMICNET.COM with the body of the message (first line only): unsubscribe
See http://www.seismicnet.com/maillist.html for more information.
Subject: Re: Sensor noise From: Barry Lotz barry_lotz@............. Date: Tue, 29 Dec 2009 05:54:59 -0800 (PST) Brett Yeah. I also forgot about the phase angle at a particular frequency . Why d= o you think a low pass rather than a=A0 notch filter, centered at the micro= seismic frequency zone, is used?. That way you aren't totally eliminating t= he higher frequencies and potentially the P an maybe S signals. That's the = beauty of winquake. You can play with the signal later.=20 Regards Barry http://www.seismicvault.com --- On Tue, 12/29/09, Brett Nordgren wrote: From: Brett Nordgren Subject: Re: Sensor noise To: psn-l@.............. Date: Tuesday, December 29, 2009, 5:26 AM Hi Barry, Good try but, unfortunately, I don't think so. At 09:12 PM 12/28/2009 -0800, you wrote: > All > I have successfully used a running fft to sense signal frequency componen= t changes and used this as a trigger mechanism for an event. Could one use = the=A0 ( I guess you call it ) power spectrum of the signal just before and= during the event to remove the noise? I guess you would have to use the sa= me time window so the frequencies would compare. Could it be a simple subtr= action of the "before" from the "during"? This would assume that the backgr= ound noise didn't change in the period during an event. By its very nature, noise *is* changing....randomly.=A0 Its overall spectru= m may remain constant, but that is created by time-averaging a noise voltag= e which is constantly varying in an unpredictable way.=A0 A possible workin= g definition of noise would be 'that part of a signal which can not be pred= icted and subtracted out'. > This could be better than trying to shape a multi pole filter to eliminat= e the noise. I have found that often a portion of the event signal is in th= e same frequency range as the noise. To really reduce the noise to a minimum you have to have a quiet site and b= uild a quiet seismometer. For the noise that remains, filtering eliminates both noise and earthquake = signals.=A0 Hopefully, the worst noise will be at frequencies that are not = required to properly see the quakes.=A0 For the FBV we often filter out any= thing above 0.08 Hz, as that's where you find a lot of the noise, while muc= h of the motion from distant quakes will be below that frequency.=A0 ANMO i= n Albuquerque go even further with their Web display and filter at somethin= g like 0.05 Hz, and they sometimes don't show the higher-frequency quakes v= ery clearly that we can see fine. Regards, Brett Watch our wiggles http://bnordgren.org/seismo/gif_images.htm or watch some very very good wiggles http://aslwww.cr.usgs.gov/Seismic_Data/telemetry_data/ANMO_24hr.html __________________________________________________________ Public Seismic Network Mailing List (PSN-L)
Brett
Yeah. I also forgot about the phase = angle at a particular frequency . Why do you think a low pass rather than a=   notch filter, centered at the microseismic frequency zone, is used?.= That way you aren't totally eliminating the higher frequencies and potenti= ally the P an maybe S signals. That's the beauty of winquake. You can play = with the signal later.

Regards
Barry
http://www.seismicvault.com

--- On Tue, 12/29/09, Brett Nordgren <brett3nt@bnordgr= en.org> wrote:

From: Brett Nordg= ren <brett3nt@.............>
Subject: Re: Sensor noise
To: psn-= l@..............
Date: Tuesday, December 29, 2009, 5:26 AM

Hi Barry,

Good try but, unfortunately, I don't = think so.

At 09:12 PM 12/28/2009 -0800, you wrote:
> All
&g= t; I have successfully used a running fft to sense signal frequency compone= nt changes and used this as a trigger mechanism for an event. Could one use= the  ( I guess you call it ) power spectrum of the signal just before= and during the event to remove the noise? I guess you would have to use th= e same time window so the frequencies would compare. Could it be a simple s= ubtraction of the "before" from the "during"? This would assume that the ba= ckground noise didn't change in the period during an event.

By its v= ery nature, noise *is* changing....randomly.  Its overall spectrum may= remain constant, but that is created by time-averaging a noise voltage whi= ch is constantly varying in an unpredictable way.  A possible working = definition of noise would be 'that part of a signal which can not be predicted and subtracted out'.

> This could be better than tryin= g to shape a multi pole filter to eliminate the noise. I have found that of= ten a portion of the event signal is in the same frequency range as the noi= se.

To really reduce the noise to a minimum you have to have a quiet= site and build a quiet seismometer.

For the noise that remains, fil= tering eliminates both noise and earthquake signals.  Hopefully, the w= orst noise will be at frequencies that are not required to properly see the= quakes.  For the FBV we often filter out anything above 0.08 Hz, as t= hat's where you find a lot of the noise, while much of the motion from dist= ant quakes will be below that frequency.  ANMO in Albuquerque go even = further with their Web display and filter at something like 0.05 Hz, and th= ey sometimes don't show the higher-frequency quakes very clearly that we ca= n see fine.

Regards,
Brett

Watch our wiggles
http= ://bnordgren.org/seismo/gif_images.htm

or watch some very very g= ood wiggles
http://aslwww.cr.usgs.gov/Seismic_Da= ta/telemetry_data/ANMO_24hr.html


___________________________= _______________________________

Public Seismic Network Mailing List = (PSN-L)

To leave this list email PSN-= L-REQUEST@.............. with the body of the message (first line only)= : unsubscribe
See http://www.seismicnet.com/maillist.html for more inform= ation.
Subject: Re: Sensor noise From: Brett Nordgren brett3nt@............. Date: Tue, 29 Dec 2009 10:32:49 -0500 Hi Barry At 05:54 AM 12/29/2009 -0800, you wrote: >Brett >Yeah. I also forgot about the phase angle at a particular frequency . Also instantaneous amplitude. It is point-by-point data that you would have to be subtracting if you are looking for a point-by-point result, that is to say, a waveform. >Why do you think a low pass rather than a notch filter, centered at the >microseismic frequency zone, is used?. That way you aren't totally >eliminating the higher frequencies and potentially the P an maybe S >signals. That's the beauty of winquake. You can play with the signal later. Yes, the ability to post process the signal is very useful. There are several reasons why I don't generally use a notch filter. First the microseism zones are bands of frequencies and the notch(es) would have to be fairly wide. In addition to microseisms, generally at the higher frequencies, is all the human-caused noise, so-called cultural noise, which has pretty much unpredictable frequencies. By the time I have notched out all the noise, there's not much left and it is simpler to just use a low-pass. And even with the 12.5 second low pass filter, the larger quakes will clearly show some of the principal body phases. If I come across a future quake that I want to look at in more detail which has too much noise at a particular frequency, I may try and see what notch filtering can do. That might be particularly useful with small local quakes. Regards, Brett Watch our wiggles http://bnordgren.org/seismo/gif_images.htm or watch some very very good wiggles http://aslwww.cr.usgs.gov/Seismic_Data/telemetry_data/ANMO_24hr.html __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Downloades from the ftp server I created for PSN folks From: "Geoffrey" gmvoeth@........... Date: Tue, 29 Dec 2009 10:26:53 -0700 Thanks Ian ; But i did this for myself to play with and little more. You folks are like little AI programs running as services on my windows and i enjoy sometimes communicating with you. I never want to know you guys in reaL LIFE, iT will destroy my thoughts of a sea of truly intelligent programmers making these AI programs running in the background in my Windows Vista OS for me to communicate with. I wonder why people dont just zip or rar something like a wave file and leave it at that. I can not accept any lossy encryption into which can be embedded hidden intelligence (meaning information). I once saw this wullenwebber antenna array lying in a swampy area in the woods of new hampshire and seriously wondered who it belonged to until one day I picked up a strong spy transmission on my SW radio. It must be the CIA or someone like that because the woman I heard was totally USA dialect. I could imagine a goddess with a voice like her so perfect in every way. But more than likely a shirly temple kind of persona in reality. And not the brunhilda of the american spyworld. Thanks for your input. It makes me think of things. Regards; geoff ----- Original Message ----- From: "ian" To: Sent: Tuesday, December 29, 2009 4:01 AM Subject: Re: Downloades from the ftp server I created for PSN folks > for videos, could I suggest something like vimeo.com. You won't need to > serve the ftp requests and the video will be compressed (by vimeo) so > will download quicker. > > Just a thought. > > Ian > > Geoffrey wrote: >> MORTON SALT DISSOLVED IN TAPWATER. >> Thermal mass for thermal momentum. >> RFI absorber hopefully. >> If the human body is resistant to RFI >> then so should salt water be. I think ??? >> You got to make all the various changes be >> as common mode as possible to everything >> at the same time or it shows as unwanted noise. >> Even common mode can if its big enough. >> >> Common mode is like you shake the whole person >> instead of only their hand. >> >> >> ----- Original Message ----- From: "sismos" >> To: >> Sent: Monday, December 28, 2009 3:17 PM >> Subject: Re: Downloades from the ftp server I created for PSN folks >> >> >>> Hi Geoff, >>> >>> I downloaded the AVI file just minutes after you posted the link. I >>> live in Panama. It only took a few minutes, quite fast actually. >>> >>> I have to admit that the video was strange and looked more like a home >>> canning operation than a seismic station. I say this kindly because my >>> station look more like rats nests than seismic stations. What is in all >>> the jars? >>> >>> I really like reading your post. >>> >>> Saludos, >>> >>> Angel >>> >>> >>> On Mon, 2009-12-28 at 14:01 -0700, Geoffrey wrote: >>>> Hello PSN; >>>> >>>> I would like to let you know that everything within the scratch folder >>>> is OK for you to download. >>>> >>>> I have been watching the last several hours the progress >>>> of several downloads and come to the conclusion >>>> there is some kind of interference with connections >>>> that cross the USA border. >>>> >>>> It may not be possible for Non-USA people to >>>> download these files in a timely fashion. >>>> >>>> But do not let you stop trying because like >>>> always I could be wrong. >>>> >>>> I will post just about everything related to >>>> PSN or Seismology that I do here and it is not >>>> intended for the general public but only >>>> PSN peoples who I believe are truly >>>> interested in seismology/geophysics/programming/instrumentation. >>>> >>>> I will not be up 100% of the time. >>>> >>>> Most likely Randomly between 24:00 and 12:00 UTC >>>> when the net is least used here. >>>> >>>> FTP SERVER IP: 173.016.082.025 ( NOT STATIC can change periodically >>>> by the ISP ) >>>> FTP UID: PSN >>>> FTP PASS: PSN123 >>>> FTP PORTS: 1024 to 65535 are open with passive ftp enabled. >>>> FTP CHANNEL: 20/21 I think are standard for FTP >>>> >>>> It is for download only and not intended >>>> to let people do P2P ( peer to peer ) stuff. >>>> >>>> Don't laugh too hard since this how I have chosen to waste my life. >>>> >>>> You guys are much more serious armatures than myself. >>>> >>>> Be happy if you get better than 60KB/SEC downloads >>>> because EUROPE was getting like 1K or less for reasons >>>> not fully understood. >>>> The limits are not my machine since everything >>>> on the B drive is ramdisk ( very fast ). >>>> The connection is A Gbit modem. >>>> The limits has to be ISP or Backbone related. >>>> >>>> Its all just to show you what I do here at GVA the best I can. >>>> >>>> Question; >>>> Not sure what official armature group [GVA] is a part of >>>> to put into the PSN4 file header, possibly >>>> someone can tell me in a personal email. >>>> I will change the header from "123456" to reflect this. >>>> >>>> A USGS expert person named Bruce Presgrave assigned me this >>>> designation. >>>> But all I know is [GVA] and not any parent organization. >>>> >>>> Regards, >>>> geoff >>>> __________________________________________________________ >>>> >>>> Public Seismic Network Mailing List (PSN-L) >>>> >>>> To leave this list email PSN-L-REQUEST@.............. with the body >>>> of the message (first line only): unsubscribe >>>> See http://www.seismicnet.com/maillist.html for more information. >>>> >>> >>> __________________________________________________________ >>> >>> Public Seismic Network Mailing List (PSN-L) >>> >>> To leave this list email PSN-L-REQUEST@.............. with the body >>> of the message (first line only): unsubscribe >>> See http://www.seismicnet.com/maillist.html for more information. >>> >> __________________________________________________________ >> >> Public Seismic Network Mailing List (PSN-L) >> >> To leave this list email PSN-L-REQUEST@.............. with the body of >> the message (first line only): unsubscribe >> See http://www.seismicnet.com/maillist.html for more information. >> > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: And Now A Simple Question From: "GPayton" gpayton@............. Date: Tue, 29 Dec 2009 14:34:55 -0600 After the recent "high level" discussions, I would like to present one at MY intelligence level. (NO puns, please) Please tell me the significant differences in using the JB vs. the IASP91 tables? Given a chosen event, switching between tables will result in different times, distances and etc. How do I know WHICH to use in WinQuake. Thanks, Jerry
After the recent "high level" discussions, I would like to present = one at=20 MY intelligence level. (NO puns, please)
 
Please tell me the significant differences in using the JB vs. the = IASP91=20 tables?
 
Given a chosen event, switching between tables will result in = different=20 times, distances and etc.  How do I know WHICH to use in = WinQuake.
 
Thanks,
Jerry
Subject: Re: Sensor noise From: Larry Conklin lconklin@............ Date: Tue, 29 Dec 2009 16:16:14 -0500 Hi Barry, It sounds like you've been messing around with something similar to a project I started but didn't get around to finishing. I added a waterfall FFT plot to my data logging program, but never finished debugging it. In part because I wasn't all that confident that the plot would be worth all that much. I'd be interested in a little more information regarding how you are collecting the FFT and some of the design decisions you use (number of samples in the window, how frequently you do a conversion, etc.) Did you write your own code or are you using some 3'rd party software? Larry Conklin Liverpool, NY lconklin@............ On 12/29/2009 12:12 AM, Barry Lotz wrote: > All > I have successfully used a running fft to sense signal frequency > component changes and used this as a trigger mechanism for an event. > Could one use the ( I guess you call it ) power spectrum of the signal > just before and during the event to remove the noise? I guess you would > have to use the same time window so the frequencies would compare. Could > it be a simple subtraction of the "before" from the "during"? This would > assume that the background noise didn't change in the period during an > event. This could be better than trying to shape a multi pole filter to > eliminate the noise. I have found that often a portion of the event > signal is in the same frequency range as the noise. > > Regards > Barry > http://www.seismicvault.com > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: And Now A Simple Question From: "Geoffrey" gmvoeth@........... Date: Tue, 29 Dec 2009 18:35:09 -0700 All I can say is if you use the 91 table which i believe was created from a program by the USGS the best times I get seem to be if you choose the P91 and The S91 tables to be your P and S markers respectively you get your best times. The 91 tables are good for both regional and teleseismic i think but you must change if you want to be more selective. I have actual tables from them and seem to get distances too far when i use their tables Pg to Sg I have better luck with Pg to Lg times for some strange reason. It a matter of watching and comparing to see whats best at your location. Those tables are for real pros to use and not peoples like myself. Im just lucky if my times actually match the theoretical times. Maybe 5 seconds late I see sometimes with (often) distance differences up to 20 miles from what they say. Intellegence is not what you may think it is. Things factor in other just test taking like how long and well you can survive the ever changing times. And in some circles intelligence is simply information riding on the back of some kind of carrier wave. Maybe just morse code or the very presence of absecense of whatever is artificially produced. I often wondered about sending morse code through the ground using atomic bombs lol :-) Bunga Bunga ----- Original Message ----- From: "GPayton" To: "PSN Network List" Sent: Tuesday, December 29, 2009 1:34 PM Subject: And Now A Simple Question > After the recent "high level" discussions, I would like to present one at MY > intelligence level. (NO puns, please) > > Please tell me the significant differences in using the JB vs. the IASP91 > tables? > > Given a chosen event, switching between tables will result in different > times, distances and etc. How do I know WHICH to use in WinQuake. > > Thanks, > Jerry > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Sensor noise From: "Geoffrey" gmvoeth@........... Date: Tue, 29 Dec 2009 18:37:35 -0700 It is very valuable for a classification tool and seeing events even too small to measure. They are signals within the grass. ----- Original Message ----- From: "Larry Conklin" To: Sent: Tuesday, December 29, 2009 2:16 PM Subject: Re: Sensor noise > Hi Barry, > > It sounds like you've been messing around with something similar to a > project I started but didn't get around to finishing. I added a > waterfall FFT plot to my data logging program, but never finished > debugging it. In part because I wasn't all that confident that the plot > would be worth all that much. > > I'd be interested in a little more information regarding how you are > collecting the FFT and some of the design decisions you use (number of > samples in the window, how frequently you do a conversion, etc.) Did > you write your own code or are you using some 3'rd party software? > > Larry Conklin > Liverpool, NY > lconklin@............ > > > On 12/29/2009 12:12 AM, Barry Lotz wrote: >> All >> I have successfully used a running fft to sense signal frequency >> component changes and used this as a trigger mechanism for an event. >> Could one use the ( I guess you call it ) power spectrum of the signal >> just before and during the event to remove the noise? I guess you would >> have to use the same time window so the frequencies would compare. Could >> it be a simple subtraction of the "before" from the "during"? This would >> assume that the background noise didn't change in the period during an >> event. This could be better than trying to shape a multi pole filter to >> eliminate the noise. I have found that often a portion of the event >> signal is in the same frequency range as the noise. >> >> Regards >> Barry >> http://www.seismicvault.com >> > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Sensor noise From: Barry Lotz barry_lotz@............. Date: Tue, 29 Dec 2009 19:17:59 -0800 (PST) Larry I wrote the Quick Basic acquisition program back when storage size was an i= ssue :)=A0 Initially , before I changed the program to an FFT analysis, bec= ause of the computer speed=A0 I ran what was called a Walsh transform. It w= as similar to an FFT but you used square waves. The math was faster and I c= ould write it in assembly language. What I thought was that a=A0 quake sign= al is seen as a change in amplitude and the frequency composition of the ba= ckground signal. The "short term-long term" trigger and the like routines l= ook at signal amplitude only and not changes in frequency. What I did was t= o run an FFT on a sort of small size window ( one I could run between the a= cquisition of two data points) maybe around 512 points. At a fairly slow sa= mple rate of about 5 hz ( for teleseismic events) it covered a reasonable f= requency range and I could do it with my "slow" 286 computer. I chose certa= in frequencies to observe (based on FFTs I had run=A0 on typical previously recorded events ) and ran the short term/ long term style routi= ne on a weighted sum of these frequency amplitudes. The thought was that th= e trigger would pick up the P wave arrival.=A0 I then started recording beg= inning with a moving buffer of certain # of data points. It would ignore mo= st transients. The "noise" I had the most trouble with was wind ( not on th= e sensor), I could protect from that. It was fluctuating wind gusts that ge= nerated movement in the slab the sensor was on. My trigger threshold varied= in amplitude based on running data. It could correct for most of this wind= also. The interesting thing was I could "catch " confirmed events that I c= ould barely see with my eye "in the grass". It all became academic when it = was easier to record continuously and look for events based on what showed = up on say the USGS web site. Events you can't see very well aren't that int= eresting to look at. ---- You asked :} =A0=A0 I don't remember right now the numerical specifics, but I can look it up if you are interested. Regards Barry http://www.seismicvault.com --- On Tue, 12/29/09, Larry Conklin wrote: From: Larry Conklin Subject: Re: Sensor noise To: psn-l@.............. Date: Tuesday, December 29, 2009, 1:16 PM Hi Barry, It sounds like you've been messing around with something similar to a proje= ct I started but didn't get around to finishing.=A0 I added a waterfall FFT= plot to my data logging program, but never finished debugging it.=A0 In pa= rt because I wasn't all that confident that the plot would be worth all tha= t much. I'd be interested in a little more information regarding how you are collec= ting the FFT and some of the design decisions you use (number of samples in= the window, how frequently you do a conversion, etc.)=A0 Did you write you= r own code or are you using some 3'rd party software? Larry Conklin Liverpool, NY lconklin@............ On 12/29/2009 12:12 AM, Barry Lotz wrote: > All > I have successfully used a running fft to sense signal frequency > component changes and used this as a trigger mechanism for an event. > Could one use the ( I guess you call it ) power spectrum of the signal > just before and during the event to remove the noise? I guess you would > have to use the same time window so the frequencies would compare. Could > it be a simple subtraction of the "before" from the "during"? This would > assume that the background noise didn't change in the period during an > event. This could be better than trying to shape a multi pole filter to > eliminate the noise. I have found that often a portion of the event > signal is in the same frequency range as the noise. >=20 > Regards > Barry > http://www.seismicvault.com >=20 __________________________________________________________ Public Seismic Network Mailing List (PSN-L)
Larry
I wrote the Quick Basic acquisition = program back when storage size was an issue :)  Initially , before I c= hanged the program to an FFT analysis, because of the computer speed  = I ran what was called a Walsh transform. It was similar to an FFT but you u= sed square waves. The math was faster and I could write it in assembly lang= uage. What I thought was that a  quake signal is seen as a change in a= mplitude and the frequency composition of the background signal. The "short= term-long term" trigger and the like routines look at signal amplitude onl= y and not changes in frequency. What I did was to run an FFT on a sort of s= mall size window ( one I could run between the acquisition of two data poin= ts) maybe around 512 points. At a fairly slow sample rate of about 5 hz ( f= or teleseismic events) it covered a reasonable frequency range and I could = do it with my "slow" 286 computer. I chose certain frequencies to observe (ba= sed on FFTs I had run  on typical previously recorded events ) and ran= the short term/ long term style routine on a weighted sum of these frequen= cy amplitudes. The thought was that the trigger would pick up the P wave ar= rival.  I then started recording beginning with a moving buffer of cer= tain # of data points. It would ignore most transients. The "noise" I had t= he most trouble with was wind ( not on the sensor), I could protect from th= at. It was fluctuating wind gusts that generated movement in the slab the s= ensor was on. My trigger threshold varied in amplitude based on running dat= a. It could correct for most of this wind also. The interesting thing was I= could "catch " confirmed events that I could barely see with my eye "in th= e grass". It all became academic when it was easier to record continuously = and look for events based on what showed up on say the USGS web site. Events you can't see very well aren't that interesting to look at. -= --- You asked :}    I don't remember right now the numerical spec= ifics, but I can look it up if you are interested.
Regards
Barry
<= span style=3D"text-decoration: underline; color: rgb(64, 64, 255);">http://= www.seismicvault.com

--- On Tue, 12/29/09, Larry Conklin <= i><lconklin@............> wrote:
=
From: Larry Conklin <lconklin@............>
Subject: Re: Senso= r noise
To: psn-l@..............
Date: Tuesday, December 29, 2009, 1:= 16 PM

Hi Barry,

It sounds like you'v= e been messing around with something similar to a project I started but did= n't get around to finishing.  I added a waterfall FFT plot to my data = logging program, but never finished debugging it.  In part because I wasn't all that confident that the plot would be worth all that much.
<= br>I'd be interested in a little more information regarding how you are col= lecting the FFT and some of the design decisions you use (number of samples= in the window, how frequently you do a conversion, etc.)  Did you wri= te your own code or are you using some 3'rd party software?

Larry Co= nklin
Liverpool, NY
lconklin@............

On 12/29/2009 12:12 AM, Barry Lotz wrote:
> All
> I have = successfully used a running fft to sense signal frequency
> component= changes and used this as a trigger mechanism for an event.
> Could o= ne use the ( I guess you call it ) power spectrum of the signal
> jus= t before and during the event to remove the noise? I guess you would
>= ; have to use the same time window so the frequencies would compare. Could
> it be a simple subtraction of the "before" from the "during"= ? This would
> assume that the background noise didn't change in the = period during an
> event. This could be better than trying to shape a= multi pole filter to
> eliminate the noise. I have found that often = a portion of the event
> signal is in the same frequency range as the= noise.
>
> Regards
> Barry
> http://www.seismicvault.com
&g= t;
__________________________________________________________

Pu= blic Seismic Network Mailing List (PSN-L)

To leave this list email <= a ymailto=3D"mailto:PSN-L-REQUEST@.............." href=3D"/mc/compose?to=3D= PSN-L-REQUEST@..............">PSN-L-REQUEST@.............. with the bod= y of the message (first line only): unsubscribe
See http://www.seismicnet.com/maillist.html for more inf= ormation.
Subject: Caution on low pass filtering emphasis From: RSparks rsparks@.......... Date: Wed, 30 Dec 2009 12:45:09 -0800 Hello All, I sometimes think that we amateur seismologist over-emphasize the need for low pass filtering, with the unexpected result that we destroy the fidelity of the earthquake signal. To illustrate what we might be losing, I posted my recording of this mornings Baja quake using both raw data and HIGH PASS filtered data in the WinQuake volume format. The high pass was done using WinQuake filters set at 1 Hz, two pole. Here is a link to the posting: http://www.seismicnet.com/cgi-dos/makegif.exe?/quakes/0912/091230.185135.ebgzx.psn The trace on the bottom is the raw data. As you can see, the quake was about 1677 km from this station but there was still lots of high frequency (> 1 Hz) in the data. If filtered low pass below 1 Hz, this information would be compromised, and as you can see, there is a lot of information to be lost. Something to think about, Roger __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Caution on low pass filtering emphasis From: Brett Nordgren brett3nt@............. Date: Wed, 30 Dec 2009 16:35:19 -0500 Hi Roger, Thanks for the thoughts. You got me thinking about how I have been approaching the filtering problem. For me, what's appropriate in the way of filtering depends a lot on the nature of the quake. For local ones, (to Los Angeles) such as the Baja, I open up the low pass to 20Hz. Normally that would let through a huge amount of noise, but the signal was so large that noise was no issue and when it reached LA it still had considerable energy even above 1Hz. With distant quakes, where the signal may be very weak, the only way to see anything is to use low pass filtering, around 0.08 Hz, to get rid of the microseisms and other background noise, even at the expense of losing some of the earthquake signal. For large telesisms, where noise isn't so much of an issue, it would certainly make sense to raise the filter cutoff to let you see the important 1Hz components at full strength. Matching the filter to the quake seems to work the best. Regards, Brett At 12:45 PM 12/30/2009 -0800, you wrote: >Hello All, > >I sometimes think that we amateur seismologist over-emphasize the need for >low pass filtering, with the unexpected result that we destroy the >fidelity of the earthquake signal. To illustrate what we might be losing, >I posted my recording of this mornings Baja quake using both raw data and >HIGH PASS filtered data in the WinQuake volume format. The high pass was >done using WinQuake filters set at 1 Hz, two pole. > >Here is a link to the posting: >http://www.seismicnet.com/cgi-dos/makegif.exe?/quakes/0912/091230.185135.ebgzx.psn >The trace on the bottom is the raw data. >As you can see, the quake was about 1677 km from this station but there >was still lots of high frequency (> 1 Hz) in the data. If filtered low >pass below 1 Hz, this information would be compromised, and as you can >see, there is a lot of information to be lost. > >Something to think about, > >Roger Watch our wiggles http://bnordgren.org/seismo/gif_images.htm or watch some very very good wiggles http://aslwww.cr.usgs.gov/Seismic_Data/telemetry_data/ANMO_24hr.html __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Caution on low pass filtering emphasis From: George Bush ke6pxp@....... Date: Wed, 30 Dec 2009 13:46:22 -0800 Roger- Thanks for this reminder. I try to not filter, as a general rule and only resort to it when I can't see the signal without filtering. George At 12:45 PM 12/30/2009, you wrote: >Hello All, > >I sometimes think that we amateur seismologist over-emphasize the >need for low pass filtering, with the unexpected result that we >destroy the fidelity of the earthquake signal. To illustrate what >we might be losing, I posted my recording of this mornings Baja >quake using both raw data and HIGH PASS filtered data in the >WinQuake volume format. The high pass was done using WinQuake >filters set at 1 Hz, two pole. > >Here is a link to the posting: >http://www.seismicnet.com/cgi-dos/makegif.exe?/quakes/0912/091230.185135.ebgzx.psn >The trace on the bottom is the raw data. >As you can see, the quake was about 1677 km from this station but >there was still lots of high frequency (> 1 Hz) in the data. If >filtered low pass below 1 Hz, this information would be compromised, >and as you can see, there is a lot of information to be lost. > >Something to think about, > >Roger >__________________________________________________________ > >Public Seismic Network Mailing List (PSN-L) > >To leave this list email PSN-L-REQUEST@.............. with the body >of the message (first line only): unsubscribe >See http://www.seismicnet.com/maillist.html for more information. George Bush Sea Ranch, CA, USA 38.73775N, 123.48882W __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Caution on low pass filtering emphasis From: Thomas Dick dickthomas01@............. Date: Wed, 30 Dec 2009 16:29:21 -0600 RSparks wrote: > Hello All, > > I sometimes think that we amateur seismologist over-emphasize the need > for low pass filtering, with the unexpected result that we destroy the > fidelity of the earthquake signal. To illustrate what we might be > losing, I posted my recording of this mornings Baja quake using both > raw data and HIGH PASS filtered data in the WinQuake volume format. > The high pass was done using WinQuake filters set at 1 Hz, two pole. > > Here is a link to the posting: > http://www.seismicnet.com/cgi-dos/makegif.exe?/quakes/0912/091230.185135.ebgzx.psn > The trace on the bottom is the raw data. > As you can see, the quake was about 1677 km from this station but > there was still lots of high frequency (> 1 Hz) in the data. If > filtered low pass below 1 Hz, this information would be compromised, > and as you can see, there is a lot of information to be lost. are your sure the bottom is the raw data?? it looks a lot like my filtered data __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: DART (Data Available in Real Time) From: Barry Lotz barry_lotz@............. Date: Wed, 30 Dec 2009 18:31:42 -0800 (PST) All =A0I found a couple of=A0 NCEDC (Northern Calif=A0 Earthquake Data Center)= =A0 stations very close to my house. Daily files are available on line for = them.=A0 Is anyone familiar with the program. I can't seem to open the file= for display. Here is a link to the program? http://seismo.berkeley.edu/annual_report/ar06_07/node285.html I think they are probably strong motion sites so the data may have limited = use compare with my seismographs. Regards Barry http://www.seismicvault.com
All
 I found a couple of  NCEDC (Northern Calif  E= arthquake Data Center)  stations very close to my house. Daily files a= re available on line for them.  Is anyone familiar with the program. I= can't seem to open the file for display. Here is a link to the program?http://= seismo.berkeley.edu/annual_report/ar06_07/node285.html
I think th= ey are probably strong motion sites so the data may have limited use compar= e with my seismographs.
Regards
Barry
http://www.seismicvault.com=