"I can already see a "nighttime" microseism problem, probably =
temperature changes......which could be
a problem later in the =
fall=20
and winter. (Around 2-3 AM till after the sun is up and =
warms up a=20
little, the trace gets stronger and=20
noisy. It clears up and smoothes out later in the =
day.)"
If a magnet's strength increases, even minutely, it would affect =
the=20
induced current in the coil proportionally. This could cause the slight =
increase=20
in trace's signal strength.
My magnet is laying on the concrete floor absorbing any temperature =
changes. I am going to try to laying my magnets on a piece of thin =
Styrofoam, insulating it from the floor, and see how it responds =
tonight.
In a message=20=
dated 04/07/06, gpayton880@....... writes:
Subj:Microseisms Discuss=
ion
From: gpayton880@....... (Jerry Payton)
To: chuckbou@............. (Boudreaux, Chuck), dwheelerf5@earthlin=
k.net (Don Wheller), tekmate@.............. (Joe Lincoln), jc3@................
(Cole, John), johnstilwell@............. (Stilwell, John), ChrisAtUpw@.......
m (Chapman Chris)
Hi Jerry,
I suggest that you go to http://psn=
..quake.net/ and download the letter archives back to 1996. Decompress them i=
nto annual word processor files. You can then search for topics with 'find'.=
Have a good long read!
Amateur seismology is likely to be=20=
much more of a technical challenge than the professional variety. The profes=
sionals choose very low noise remote seismic sites, buy highly developed and=
completely engineered seismometers at >>$5 K per channel and have the=
m professionally installed, often in boreholes to reduce surface noise.
The amateur variety is very much DIY, with many en=
thusiasts constructing and then setting up their own equipment. Amateur site=
s are likely to be mediocre to appalling compared to the professional ones,=20=
so you have to learn to live with the limitations and to compensate for them=
.. When making and using your own equipment, you learn that success is hard w=
on and takes considerable time, effort and patience. You also learn how to s=
et up the level, the period and the damping, how to check the performance, i=
dentify and correct problems.
The original Lehman was OK 'for a start' back in 1976=
, but the performance was limited by the poor point / knife edge lower suspe=
nsion amongst other factors. John Cole has pioneered the rolling contact typ=
e of suspension, which dramatically improves the performance and enables you=
to set up stable periods of well over 30 sec.=20
The considerable improvements in construction, suspen=
sions, damping and detectors that have appeared during the last 30 years do=20=
not yet seem to have been reflected in a 'good simple design' available to p=
otential constructors.=20
Now Jerry, I know that you were experiencing setup pr=
oblems. What period are you using and is the damping set ~critical? Do you h=
ave a .psn file of the output?
You can expect John's seismometer to be capable of a=20=
period of over 25 sec, even in a poor environment. You need to achieve this=20=
sort of period or greater to enable you to detect the long period Love waves=
.. If you aren't achieving this, you need to reduce the small angle between t=
he suspension axis and the vertical. It could be that the floor is not level=
, that you have not assembled it quite correctly, or that something has got=20=
bent / damaged in transit. If you are NOT getting a long period, THE ANGLE I=
S WRONG. The screw extension on the top wire has very little effect on the p=
eriod - it just enables you to get the mass at a suitable height above the f=
loor.
Hello Out There: PSN=20=
& ATN
=20
I'm throwing this out for discussion and / or experimentation to the=20=
group(s) as a whole. Anyone investigated this problem? If it is=20=
temperature fluctuations, what is it affecting, the coil, the pendulum, or w=
hat? The fact that the trace get amplified somewhat (in my case) indic=
ates to me that it may be affecting the electrical part: coil or magnets the=
mselves?
You have not really descr=
ibed your problems well enough for us to advise you.=20
There is background environmental n=
oise which changes with time, the weather and a wide range of human activiti=
es. Microseismic ocean background is usually at about 6 sec and near sine wa=
ve, which again changes phase and amplitude with time. This exists at all ti=
mes. Wind noise can give a range of short to very long period signals. The s=
eismometer is very sensitive to changes in the tilt angle, from a variety of=
sources - the walk up test. It is very sensitive to drafts and may also be=20=
noisy when the external temperature falls below the instrument temperature,=20=
due to convection. You need an insulating cover with all the joins 100% seal=
ed. If the joins are not airtight, it will likely be noisy.
You may also experience electronic=20=
problems due to pickup from transients on the house power wiring. Fridges of=
ten give problems. Some areas have noisy supplies. Electric trains can cause=
problems. Do you have the input line to the amplifier screened and the scre=
en and 0V line earthed? Some of the older / foreign computers had very inade=
quately filtered power supplies. Do you have a local radio transmitter, a TV=
station or a phone transmitter aerial close by? One test is to wedge=20=
the mass in position and take a trace.=20
I suggest that you set the recordin=
g for a 24 hr drumplot display. This should sort out any time variations.
What's the affect of cooling on a magnet's flux strength -- or on the in=
duced
voltage in a coil?
Insignificant with your i=
nstrument.
Obviously, supplying=20=
a heat source might help. There must be a "cure", not a patch.
=20
(snip)
"I can already see a "nighttime" microseism problem, probably temp=
erature changes......which could be=20
a problem later in the fall and winter. (Around 2-3 AM till after=20=
the sun is up and warms up a little, the trace gets stronger an=
d noisy. It clears up and smoothes out later in the day.)"
(snip)
"I experience this during the winter. My sensor in inside my home=
so I have no problems during the summer. However, I typically turn the heat=
ing unit down at night. This is when I get the problems. I placed a light bu=
lb in the closet that helps quite a bit. I usually only turn it on during th=
e winter. Several of us have experienced this problem. Maybe it's something=20=
we can work on and figure out a solution."
A known and well documented problem=
, for those who are not too lazy to read up the psn archives.
Only you DON'T use a light bulb. Th=
is just attracts flying insects, spiders and creepy crawlies. You have enoug=
h problems without inviting 'bug quakes'. Bulbs also move the air due to con=
vection.=20
With so many advisors, I wonder if=20=
some of the advice may be conflicting? You have not said what you have been=20=
advised and what steps you have taken.=20
Regards,
Chris Chapman
Subject: Re: Microseisms Discussion
From: "Jerry Payton" gpayton880@.......
Date: Tue, 4 Jul 2006 21:32:39 -0500
Chris,
I appreciate your input, your education, your knowledge and experience. I
really do. That is why I included you in my email to everyone.
Since you asked, I have achieved a 14-16 sec. period and from what others
tell me and what I read on PSN stations list, it is not that bad to start
with and learn.. That is what I am trying to discover.....is it good
enough!
My overnight "wiggles" seem to me to be possibility related to temperature
variations because it goes away later in the morning after daytime warming
up. I do not have enough community related noise close enough to cause
problems. I have placed a piece of foam under the magnets and see what
happens tonight. I know you told me that was not the problem! But, I have
to check it out. Also, I have no idea what material the magnets are made
from since John bought them (source unknown)
Chris, I realize that the amateur seismology community does NOT have the
mega-bucks for equipment and must suffer the limitations, but that it NO
reason not to strive for better performance, troubleshoot problems and
strive to improve equipment, within our budgets! Don't tell me that it
can't be done. I won't accept that.
Don't tell me that my damned floor is not level either. What floor is,
totally. That is what the leveling screws are for and I did that. I
understand about the angle adjustment too, but simply saying that it needs
to changed does not make it easy to accomplish.
The sensor worked for John before he sent it to me. I will make it work for
me too, and improve its performance if I can. I do not want to redesign or
rebuild it. After all, it is mostly all his sensors that you see posted on
the PSN website. Where are all those other BETTER posts? The proof is in
the pudding. Isn't that what they say?
I don't mean to be disrespectful, but I am not a scientist or engineer. I'm
doing the best I can with the knowledge and money I have......which ain't
much :>)
Regards,
Jerry
.
Chris,
I appreciate your input, your education, your knowledge and=20
experience. I really do. That is why I included you in my =
email to=20
everyone.
Since you asked, I have achieved a 14-16 sec. period and from what =
others=20
tell me and what I read on PSN stations list, it is not that bad to =
start=20
with and learn.. That is what I am trying to discover.....is it =
good=20
enough!
My overnight "wiggles" seem to me to be possibility =
related to=20
temperature variations because it goes away later in the morning after =
daytime=20
warming up. I do not have enough community related noise close =
enough to=20
cause problems. I have placed a piece of foam under the magnets =
and see=20
what happens tonight. I know you told me that was not the=20
problem! But, I have to check it out. Also, I have no =
idea what=20
material the magnets are made from since John bought them (source=20
unknown)
Chris, I realize that the amateur seismology community does =
NOT have=20
the mega-bucks for equipment and must suffer the limitations, but that =
it NO=20
reason not to strive for better performance, troubleshoot =
problems and=20
strive to improve equipment, within our budgets! Don't tell =
me that=20
it can't be done. I won't accept that.
Don't tell me that my damned floor is not level either. What =
floor=20
is, totally. That is what the leveling screws are for and I did=20
that. I understand about the angle adjustment too, but simply =
saying that=20
it needs to changed does not make it easy to accomplish.
The sensor worked for John before he sent it to me. I will =
make it=20
work for me too, and improve its performance if I can. I do not =
want to=20
redesign or rebuild it. After all, it is mostly all his sensors =
that you=20
see posted on the PSN website. Where are all those other =
BETTER=20
posts? The proof is in the pudding. Isn't that what they =
say?
I don't mean to be disrespectful, but I am not a scientist or=20
engineer. I'm doing the best I can with the knowledge and money I=20
have......which ain't much :>)
Regards,
Jerry
.
Subject: Check you VHS video tapes...for crossed rod pivot parts
From: "meredith lamb" paleoartifact@.........
Date: Wed, 5 Jul 2006 13:03:15 -0600
Hi all,
Heyyyyy...this part seemingly has real potential ! If you even vaguely have
followed last
years emails on crossed rod pivot/hinges; this might be something you can
also try
during any bored or curious moments.
Its within common VHS video tape cassettes. Most all cassettes use two tape
spacer/
guides, that appear to be ultra smooth stainless steel. The minority can be
plastic.
Most of them appear to be punched/stamped out of sheet metal and then formed
into a round tube; and then they appear to have been further smoothed to
where they
don't damage the video tape moving over their surfaces. The rarest
spacer/guide is a
complete cut off tube. You can open the release latch on the side of the
cassette to
view parts of these tubes behind the tape. You can generally easily open to
remove
them by first removing 5 small phillips head screws on the bottom of the
cassette
itself. The rare cassette might be plastic welded shut.
The main point here being the very smooth surface of these metal tubes is
what one
absolutely needs for a crossed rod pivot. Naturally, the contact points
won't be over
the lengthwise joint. Being as they are essentially tubes, one can use
bolts and
nuts to seat/mount them, which is also very convenient. If you only use
these, you
only need 4 (2 cassettes) tubes; 2 for running in one spaced apart
direction, and 2
"cross rod" (right angle to the other two) to attach to either side of the
boom you
use. They appear to all be ~ .630" length (16.0mm), .225" outside diameter
(5.75mm),
..190" inside diameter (4.90mm), with a wall thickness of .0175" (.5mm).
The second main point here, is that from testing a variety of solid rod kind
of
material late last year; their low friction level is absolutely amazing.
This means
greater seismic sensitivity especially for the low level mass enertia
offsets we
either can or can't sensor pickup with a majority of "home brew"
seismometers.
Credit Chris Chapman for bringing up the "crossed rod pivot" subject late
last year!
I intend to try such first as another "test table top edge" setup
eventually; where
there is only the pivot arrangement, and a test boom and mass. This would
be a
gravity vertical hanging mass pendulum. Its not really a S-G per-say; as
S-G's use
flexible strips of metal (torque limiting) as the
pivots...which...essentially....make
them kind of partial accelerometers. This would be a horizontal directional
sensing
unit. Will get back with you all later....with the specific test model
results; whether
its good, bad, or somewhere inbetween, as compared to solid rods tests of
the past.
Meredith Lamb
Hi all,
Heyyyyy...this part seemingly has real potential ! If you even vaguely have followed last
years emails on crossed rod pivot/hinges; this might be something you can also try
during any bored or curious moments.
Its within common VHS video tape cassettes. Most all cassettes use two tape spacer/
guides, that appear to be ultra smooth stainless steel. The minority can be plastic.
Most of them appear to be punched/stamped out of sheet metal and then formed
into a round tube; and then they appear to have been further smoothed to where they
don't damage the video tape moving over their surfaces. The rarest spacer/guide is a
complete cut off tube. You can open the release latch on the side of the cassette to
view parts of these tubes behind the tape. You can generally easily open to remove
them by first removing 5 small phillips head screws on the bottom of the cassette
itself. The rare cassette might be plastic welded shut.
The main point here being the very smooth surface of these metal tubes is what one
absolutely needs for a crossed rod pivot. Naturally, the contact points won't be over
the lengthwise joint. Being as they are essentially tubes, one can use bolts and
nuts to seat/mount them, which is also very convenient. If you only use these, you
only need 4 (2 cassettes) tubes; 2 for running in one spaced apart direction, and 2
"cross rod" (right angle to the other two) to attach to either side of the boom you
use. They appear to all be ~ .630" length (16.0mm), .225" outside diameter (5.75mm),
.190" inside diameter (4.90mm), with a wall thickness of .0175" (.5mm).
The second main point here, is that from testing a variety of solid rod kind of
material late last year; their low friction level is absolutely amazing. This means
greater seismic sensitivity especially for the low level mass enertia offsets we
either can or can't sensor pickup with a majority of "home brew" seismometers.
Credit Chris Chapman for bringing up the "crossed rod pivot" subject late last year!
I intend to try such first as another "test table top edge" setup eventually; where
there is only the pivot arrangement, and a test boom and mass. This would be a
gravity vertical hanging mass pendulum. Its not really a S-G per-say; as S-G's use
flexible strips of metal (torque limiting) as the pivots...which...essentially....make
them kind of partial accelerometers. This would be a horizontal directional sensing
unit. Will get back with you all later....with the specific test model results; whether
its good, bad, or somewhere inbetween, as compared to solid rods tests of the past.
Meredith Lamb
Subject: Re: Microseisms Discussion
From: =?ISO-8859-1?Q?J=F3n_Fr=EDmann?= jonfr500@.........
Date: Thu, 06 Jul 2006 15:23:16 +0000
Hi Jerry
Can you give me a sample trace of the noise that you are getting ? Gif
image of a psn file.
Regards.
--
Jón Frímann
http://www.jonfr.com
http://www.simnet.is/jonfr500/earthquake/
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Microseisms Discussion
From: "Jerry Payton" gpayton880@.......
Date: Thu, 6 Jul 2006 10:33:03 -0500
Thank you Jon, but I am told that this is normal. (My helicorder.gif is
displayed on http://teleseismic.net/helicorders/ at the bottom of the page
from Springdale, AR)
I adjusted my amplifier gain pot last night and may still do some
adjustments in days to come. Therefore, my GIF may look abnormal from time
to time.
I also live away from normal traffic, but among a LOT of trees, which I am
told may cause a high noise level. In short, I am told that it is normal
and is not for me to worry about.
Thank you for answering my plea.
Regards,
Jerry
----- Original Message -----
From: Jón Frímann
To: psn-l@..............
Sent: Thursday, July 06, 2006 10:23 AM
Subject: Re: Microseisms Discussion
Hi Jerry
Can you give me a sample trace of the noise that you are getting ? Gif
image of a psn file.
Regards.
--
Jón Frímann
http://www.jonfr.com
http://www.simnet.is/jonfr500/earthquake/
__________________________________________________________
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.
Thank you Jon, but I am told that this is normal. (My =
helicorder.gif=20
is displayed on
http://teleseismic.net/helic=
orders/ at=20
the bottom of the page from Springdale, AR)
I adjusted my amplifier gain pot last night and may still do some=20
adjustments in days to come. Therefore, my GIF may look =
abnormal from=20
time to time.
I also live away from normal traffic, but among a LOT of trees, =
which I am=20
told may cause a high noise level. In short, I am told that it is =
normal=20
and is not for me to worry about.
Thank you for answering my plea.
Regards,
Jerry
----- Original Message -----
From:=20
J=F3n =
Fr=EDmann=20
Sent: Thursday, July 06, 2006 =
10:23=20
AM
Subject: Re: Microseisms =
Discussion
Hi Jerry
Can you give me a sample trace of the =
noise=20
that you are getting ? Gif
image of a psn =
file.
Regards.
--=20
J=F3n Fr=EDmann
http://www.jonfr.com
http://www.simnet.is/j=
onfr500/earthquake/
__________________________________________=
________________
Public=20
Seismic Network Mailing List (PSN-L)
To leave this list email =
PSN-L-REQUEST@...............
=20
with
the body of the message (first line only): unsubscribe
See =
http://www.seismicnet.co=
m/maillist.html=20
for more information.
Subject: Re: Microseisms Discussion
From: =?ISO-8859-1?Q?J=F3n_Fr=EDmann?= jonfr500@.........
Date: Thu, 06 Jul 2006 16:53:52 +0000
Hi Jerry
Are you using a low pass filter on the graph that you have online ?
Becose there normally isn't alot of noise below 5Hz.
Regards.
--
Jón Frímann
http://www.jonfr.com
http://www.simnet.is/jonfr500/earthquake/
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Microseisms Discussion
From: "Jerry Payton" gpayton880@.......
Date: Thu, 6 Jul 2006 12:19:04 -0500
Yes, Lo setting is 0.10 with 2 poles and Hi setting is 0.05 with 2 poles.
Be advise that I am interested in teleseismic events, primarily.
Jerry
----- Original Message -----
From: Jón Frímann
To: psn-l@..............
Sent: Thursday, July 06, 2006 11:53 AM
Subject: Re: Microseisms Discussion
Hi Jerry
Are you using a low pass filter on the graph that you have online ?
Becose there normally isn't alot of noise below 5Hz.
Regards.
--
Jón Frímann
http://www.jonfr.com
http://www.simnet.is/jonfr500/earthquake/
__________________________________________________________
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.
Yes, Lo setting is 0.10 with 2 poles and Hi setting is 0.05 =
with 2=20
poles. Be advise that I am interested in teleseismic events,=20
primarily.
Jerry
----- Original Message -----
From:=20
J=F3n =
Fr=EDmann=20
Sent: Thursday, July 06, 2006 =
11:53=20
AM
Subject: Re: Microseisms =
Discussion
Hi Jerry
Are you using a low pass filter on the =
graph=20
that you have online ?
Becose there normally isn't alot of noise =
below=20
5Hz.
Regards.
--
J=F3n Fr=EDmann
http://www.jonfr.com
http://www.simnet.is/j=
onfr500/earthquake/
__________________________________________=
________________
Public=20
Seismic Network Mailing List (PSN-L)
To leave this list email =
PSN-L-REQUEST@...............
=20
with
the body of the message (first line only): unsubscribe
See =
http://www.seismicnet.co=
m/maillist.html=20
for more information.
Subject: Tajikistan earthquake swarm
From: =?ISO-8859-1?Q?J=F3n_Fr=EDmann?= jonfr500@.........
Date: Fri, 07 Jul 2006 00:47:48 +0000
Hi all
There has been a intresting earthquake swarm in Tajikistan since 03:57
last night. It got started off by a mag 5.7 earthquakes, there has been
alot of aftershock activite. The largest aftershock has been a mag 4.7.
I find the location intresting, since there isn't any subduction zone
there or other type of fault zone. Aftershock activite is still ongoing
according to emsc-csem.
Regards.
--
Jón Frímann
http://www.jonfr.com
http://www.simnet.is/jonfr500/earthquake/
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Tajikistan earthquake swarm
From: Dave Nelson davenn@...............
Date: Fri, 07 Jul 2006 20:17:07 +1000
Hi Jon
this is a MAJOR fault zone being on the western side of=20
the India -Asia Collision Zone. this whole region from Tajikistan right to=
=20
the east across the Tibetan Plateau is undergoing severe compression as=20
India rams its way into the Asian Continent. As a result many thrust and=20
strikeslip form as the material is squeezed
out to the eastern and western sides of the zone.
in this region you will find that most of the river valleys are actually=
=20
faultlines
that have been eroded out by riverflow as the crushed rock in the fault=20
line is softer than the surrounding material.
You can do a basic model this effect for yourself using a block of=20
semi-rigid material
like childrens play-dough as Asia and push a smaller width block of wood=20
into one side
and watch the play-dough squeeze out the sides
look here for pic of basic idea
http://www.sydneystormcity.com/india-asia_collision.bmp
cheers
Dave N
At 12:47 AM 7/07/2006 +0000, you wrote:
>Hi all
>There has been a intresting earthquake swarm in Tajikistan since 03:57
>last night. It got started off by a mag 5.7 earthquakes, there has been
>alot of aftershock activite. The largest aftershock has been a mag 4.7.
>I find the location intresting, since there isn't any subduction zone
>there or other type of fault zone. Aftershock activite is still ongoing
>according to emsc-csem.
>Regards.
>J=F3n Fr=EDmann
>http://www.jonfr.com
>http://www.simnet.is/jonfr500/earthquake/
>
>__________________________________________________________
>
>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.
>
>
>
>--
>No virus found in this incoming message.
>Checked by AVG Anti-Virus.
>Version: 7.1.394 / Virus Database: 268.9.9/382 - Release Date: 4/07/2006
--
No virus found in this outgoing message.
Checked by AVG Anti-Virus.
Version: 7.1.394 / Virus Database: 268.9.9/382 - Release Date: 4/07/2006
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Tajikistan earthquake swarm
From: John or Jan Lahr JohnJan@........
Date: Fri, 07 Jul 2006 08:54:01 -0700
Hi Jon,
For an excellent overview of global tectonics, there is a new version
of the This Dynamic Planet poster available here:
http://www.minerals.si.edu/tdpmap/. The PDF version is huge, but
once downloaded would be very helpful via the zoom-in tool of Adobe reader.
During the past few years the USGS has produced a summary posters
following the most significant earthquakes. They are very helpful in
providing insight into the tectonics of each region. For example, this poster:
ftp://hazards.cr.usgs.gov/maps/sigeqs/20020325/20020325.pdf was made
following a 2002 magnitude 7.4 event in the Hindu Kush. Again, the
pdf format is large, but includes all of the details when the zoom-in
tool of Adobe reader is used.
Links to all of the posters are included here:
http://earthquake.usgs.gov/eqcenter/eqarchives/poster/
Cheers,
John
At 03:17 AM 7/7/2006, you wrote:
> Hi Jon
> this is a MAJOR fault zone being on the western
> side of the India -Asia Collision Zone. this whole region from
> Tajikistan right to the east across the Tibetan Plateau is
> undergoing severe compression as India rams its way into the Asian
> Continent. As a result many thrust and strikeslip form as the
> material is squeezed out to the eastern and western sides of the zone....
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Tajikistan earthquake swarm
From: "Jerry Payton" gpayton880@.......
Date: Fri, 7 Jul 2006 11:36:02 -0500
Jon,
I agree with John. I just bought the full poster from USGS and it is a
"dandy."
Jerry Payton
----- Original Message -----
From: John or Jan Lahr
To: psn-l@..............
Sent: Friday, July 07, 2006 10:54 AM
Subject: Re: Tajikistan earthquake swarm
Hi Jon,
For an excellent overview of global tectonics, there is a new version
of the This Dynamic Planet poster available here:
http://www.minerals.si.edu/tdpmap/. The PDF version is huge, but
once downloaded would be very helpful via the zoom-in tool of Adobe
reader.
During the past few years the USGS has produced a summary posters
following the most significant earthquakes. They are very helpful in
providing insight into the tectonics of each region. For example, this
poster:
ftp://hazards.cr.usgs.gov/maps/sigeqs/20020325/20020325.pdf was made
following a 2002 magnitude 7.4 event in the Hindu Kush. Again, the
pdf format is large, but includes all of the details when the zoom-in
tool of Adobe reader is used.
Links to all of the posters are included here:
http://earthquake.usgs.gov/eqcenter/eqarchives/poster/
Cheers,
John
At 03:17 AM 7/7/2006, you wrote:
> Hi Jon
> this is a MAJOR fault zone being on the western
> side of the India -Asia Collision Zone. this whole region from
> Tajikistan right to the east across the Tibetan Plateau is
> undergoing severe compression as India rams its way into the Asian
> Continent. As a result many thrust and strikeslip form as the
> material is squeezed out to the eastern and western sides of the
zone....
__________________________________________________________
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.
Jon,
I agree with John. I just bought the full poster from =
USGS and=20
it is a "dandy."
Jerry Payton
----- Original Message -----
From:=20
John or =
Jan Lahr=20
Sent: Friday, July 07, 2006 =
10:54=20
AM
Subject: Re: Tajikistan =
earthquake=20
swarm
Hi Jon,
For an excellent overview of global =
tectonics,=20
there is a new version
of the This Dynamic Planet poster available =
here:
http://www.minerals.si.edu/td=
pmap/. =20
The PDF version is huge, but
once downloaded would be very helpful =
via the=20
zoom-in tool of Adobe reader.
During the past few years the =
USGS has=20
produced a summary posters
following the most significant=20
earthquakes. They are very helpful in
providing insight into =
the=20
tectonics of each region. For example, this poster:
ftp:=
//hazards.cr.usgs.gov/maps/sigeqs/20020325/20020325.pdf =20
was made
following a 2002 magnitude 7.4 event in the Hindu =
Kush. =20
Again, the
pdf format is large, but includes all of the details =
when the=20
zoom-in
tool of Adobe reader is used.
Links to all of the =
posters=20
are included here:
http://ea=
rthquake.usgs.gov/eqcenter/eqarchives/poster/
Cheers,
John<=
BR>
At=20
03:17 AM 7/7/2006, you wrote:
> Hi=20
=
Jon
> &n=
bsp; =20
this is a MAJOR fault zone being on the western
> =
side of=20
the India -Asia Collision Zone. this whole region from
>=20
Tajikistan right to the east across the Tibetan Plateau is
> =
undergoing=20
severe compression as India rams its way into the Asian
>=20
Continent. As a result many thrust and strikeslip form as the =
>=20
material is squeezed out to the eastern and western sides of the=20
=
zone....
_____________________________________________________=
_____
Public=20
Seismic Network Mailing List (PSN-L)
To leave this list email =
PSN-L-REQUEST@...............
=20
with
the body of the message (first line only): unsubscribe
See =
http://www.seismicnet.co=
m/maillist.html=20
for more information.
Subject: Re: Microseisms Discussion
From: ChrisAtUpw@.......
Date: Fri, 7 Jul 2006 13:14:57 EDT
In a message dated 06/07/06, gpayton880@....... writes:
> Are you using a low pass filter on the graph that you have online ?
> Because there normally isn't a lot of noise below 5Hz.
> Yes, Lo setting is 0.10 with 2 poles and Hi setting is 0.05 with 2 poles.
> Be advise that I am interested in teleseismic events, primarily.
Hi Jerry,
If you view the trace with these filter selections, YOU WILL MISS the
P & S waves which give you the earthquake timing. For these you need
frequencies from 2 Hz to 0.5 Hz. The much larger long period Love waves are fine for
picking up a quake.
> . (My helicorder.gif is displayed on http://teleseismic.net/helicorders/
> at the bottom of the page from Springdale, AR)
The commoner non seismic signals are air convection noise, traffic and
similar noise, sun / wind / draft / weather related noise and powerline
interference. However, you may get combinations of these signals.
FC1 from Friendswood Texas seems to be showing a lot of single pole /
asymmetric signals. I wonder if this could be powerline problems?
JL1 Hor at Spring Texas shows what appears to be chamber convection
noise, starting at about 19.00 local and stopping about 5 - 6.00 after dawn.
JS2 from Houston Texas shows strong signals starting at about 7.00 and
reducing after 13.00. Could this be air convection noise in a room which is
heated by the morning sun?
JS1 from Houston shows noise from about 7.00 and going on till late
evening. Could this be traffic related?
> I also live away from normal traffic, but among a LOT of trees, which I am
> told may cause a high noise level. In short, I am told that it is normal and
> is not for me to worry about.
JP1 from Springdale shows noise from about midnight till 10.00. Could
this be related to wind? Midnight seems late for the start of chamber air
convection noise, but by no means impossible. Is this behavoir repeatable?
Have you though of getting a small weather station? It could keep
track of the temperature changes and the wind speed and direction, which are
likely to effect you with many trees nearby. The basic Davis starts at about $200.
If you have a spare channel on your ADC, you might buy a couple of
photo diodes, connect them in parallel, but ~at right angles and record the
daylight / sun intensity? (45 deg to the vertical on an E/W axis.) This could give
you a fairly accurate indication of the solar heating.
I cut a hole in a ping-pong ball, stuck in a silicon photodiode with
silicone rubber cement and mounted it vertically, where sunlight could reach it
all day. The plastic ball acts as an 'integrating sphere' to give a near
average light value, but it weathers slowly and needs to replaced once a year. It
indicates dusk / dawn, whether it is cloudy or bright, etc.
You can also get a fairly good indication of sunpower by using two
thermometers, one screened and that other painted black and placed in the sun.
Regards,
Chris Chapman
In a me=
ssage dated 06/07/06, gpayton880@....... writes:
Are you using a low pass filter=
on the graph that you have online ?
Because there normally isn't a lot of noise below 5Hz.
Yes, Lo setting is 0.10 with 2=20=
poles and Hi setting is 0.05 with 2 poles. Be advise that I am i=
nterested in teleseismic events, primarily.
Hi Jerry,
If you view the trace with these filter=
selections, YOU WILL MISS the P & S waves which give you the earthquake=
timing. For these you need frequencies from 2 Hz to 0.5 Hz. The much larger=
long period Love waves are fine for picking up a quake.
. (My helicorder.gif is d=
isplayed on http://teleseism=
ic.net/helicorders/ at the bottom of the page from Springdale, AR) =
The commoner non seismic signals are ai=
r convection noise, traffic and similar noise, sun / wind / draft / weather=20=
related noise and powerline interference. However, you may get combinations=20=
of these signals.
FC1 from Friendswood Texas seems to be=20=
showing a lot of single pole / asymmetric signals. I wonder if this could be=
powerline problems?
JL1 Hor at Spring Texas shows what appe=
ars to be chamber convection noise, starting at about 19.00 local and stoppi=
ng about 5 - 6.00 after dawn.
JS2 from Houston Texas shows strong sig=
nals starting at about 7.00 and reducing after 13.00. Could this be air conv=
ection noise in a room which is heated by the morning sun?
JS1 from Houston shows noise from about=
7.00 and going on till late evening. Could this be traffic related?
I also live away from normal tr=
affic, but among a LOT of trees, which I am told may cause a high noise leve=
l. In short, I am told that it is normal and is not for me to worry ab=
out.
JP1 from Springdale shows noise from ab=
out midnight till 10.00. Could this be related to wind? Midnight seems late=20=
for the start of chamber air convection noise, but by no means impossible. I=
s this behavoir repeatable?
Have you though of getting a small weat=
her station? It could keep track of the temperature changes and the wind spe=
ed and direction, which are likely to effect you with many trees nearby. The=
basic Davis starts at about $200.
If you have a spare channel on your ADC=
, you might buy a couple of photo diodes, connect them in parallel, but ~at=20=
right angles and record the daylight / sun intensity? (45 deg to the vertica=
l on an E/W axis.) This could give you a fairly accurate indication of the s=
olar heating.
I cut a hole in a ping-pong ball, stuck=
in a silicon photodiode with silicone rubber cement and mounted it vertical=
ly, where sunlight could reach it all day. The plastic ball acts as an 'inte=
grating sphere' to give a near average light value, but it weathers slowly a=
nd needs to replaced once a year. It indicates dusk / dawn, whether it is cl=
oudy or bright, etc.
You can also get a fairly good in=
dication of sunpower by using two thermometers, one screened and that other=20=
painted black and placed in the sun.
Regards,
Chris Chapman
Subject: Help with telemetry equipment
From: "Wayne Abraham" gold1146@...........
Date: Sat, 08 Jul 2006 04:27:28 +0000
Hello all
I am in the process of designing a three-station seismic network for
monitoring two volcanoes within 8 kilometers of my home. I already have a
geophone buried at my house and am monitoring a nearby telemetered site. I
would like to install two remote stations using geophones, low-power
transmitters and Larry's amplifier board.
My main problem is converting the amplified seismic signal to a tone for
transmition (the received signal will be decoded using Larry's decoder
board). Does anyone on this list have schematics, internet links or know of
anyone selling this encoding equipment?
Thanks for your help
Wayne
http://dominicapsn.freeyellow.com
_________________________________________________________________
Express yourself instantly with MSN Messenger! Download today it's FREE!
http://messenger.msn.click-url.com/go/onm00200471ave/direct/01/
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Help with telemetry equipment
From: ChrisAtUpw@.......
Date: Sat, 8 Jul 2006 09:56:05 EDT
In a message dated 08/07/06, gold1146@........... writes:
> Does anyone on this list have schematics, internet links or know of
> anyone selling this encoding equipment?
Hi There,
As far as I know all encoders use the XR2206 function generator chip.
Regards,
Chris Chapman
In a me=
ssage dated 08/07/06, gold1146@........... writes:
Does anyone on this list have s=
chematics, internet links or know of
anyone selling this encoding equipment?
Hi There,
As far as I know all encoders use the X=
R2206 function generator chip.
Regards,
Chris Chapman
Subject: Re: Help with telemetry equipment
From: Larry Cochrane lcochrane@..............
Date: Sun, 09 Jul 2006 14:27:33 -0700
Hi Wayne,
You will also need to buy or build a demodulator board other then mine. I no longer
sell my USGS Telemetry demodulator board since I never sold enough of them to go into
production. I wish I could help you out, but right now I have two big projects going
on and my plate is pretty full for the next few months.
Regards,
Larry Cochrane
Redwood City, PSN
Wayne Abraham wrote:
> Hello all
>
> I am in the process of designing a three-station seismic network for
> monitoring two volcanoes within 8 kilometers of my home. I already have a
> geophone buried at my house and am monitoring a nearby telemetered site. I
> would like to install two remote stations using geophones, low-power
> transmitters and Larry's amplifier board.
>
> My main problem is converting the amplified seismic signal to a tone for
> transmition (the received signal will be decoded using Larry's decoder
> board). Does anyone on this list have schematics, internet links or know of
> anyone selling this encoding equipment?
>
> Thanks for your help
> Wayne
> http://dominicapsn.freeyellow.com
>
> _________________________________________________________________
> Express yourself instantly with MSN Messenger! Download today it's FREE!
> http://messenger.msn.click-url.com/go/onm00200471ave/direct/01/
>
> __________________________________________________________
>
> 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: Help with a Lehman
From: Mike Speed mike8s2@.........
Date: Sun, 9 Jul 2006 20:06:55 -0700 (PDT)
Hi all,
I've been thinking of building a Lehman and was wondering what practical considerations I might run in to if I significantly lengthen the boom.
Also, I've read at least one account in which a Lehman device produced a "spurious" signal due to vibration of the supporting wire. What is your view on this, i.e., is it a significant enough noise source to devise a means of damping this out?
Greg
---------------------------------
How low will we go? Check out Yahoo! Messengers low PC-to-Phone call rates.
Hi all,
I've been thinking of building a Lehman and was wondering what practical considerations I might run in to if I significantly lengthen the boom.
Also, I've read at least one account in which a Lehman device produced a "spurious" signal due to vibration of the supporting wire. What is your view on this, i.e., is it a significant enough noise source to devise a means of damping this out?
Greg
How low will we go? Check out Yahoo! Messengers low PC-to-Phone call rates.
Subject: Re: Help with telemetry equipment
From: ChrisAtUpw@.......
Date: Sun, 9 Jul 2006 23:38:14 EDT
In a message dated 09/07/06, lcochrane@.............. writes:
> You will also need to buy or build a demodulator board other then mine. I
> no longer
> sell my USGS Telemetry demodulator board since I never sold enough of them
> to go into production.
Hi Larry,
In that case could you put the circuit diagram on your website,
please?
This would be most helpful.
Regards,
Chris Chapman
In a me=
ssage dated 09/07/06, lcochrane@.............. writes:
You will also need to buy or bu=
ild a demodulator board other then mine. I no longer
sell my USGS Telemetry demodulator board since I never sold enough of them t=
o go into production.
Hi Larry,
In that case could you put the circuit=20=
diagram on your website, please?
This would be most helpful.
Regards,
Chris Chapman
Subject: Re: Help with a Lehman
From: ChrisAtUpw@.......
Date: Mon, 10 Jul 2006 00:07:34 EDT
In a message dated 10/07/06, mike8s2@......... writes:
> I've been thinking of building a Lehman and was wondering what practical
> considerations I might run in to if I significantly lengthen the boom.
Hi Mike,
Lengthen the boom to what? 2ft is about enough unless you want periods
over 40 sec. The main considerations are the damping, which is far easier if
you use magnet + plate damping and the bottom bearing. The old points and
knife blades are not satisfactory and are likely to seriously limit your response.
The rolling ball and the crossed cylinders are fine. See
http://pages.prodigy.net/fxc/ and links
> Also, I've read at least one account in which a Lehman device produced a
> "spurious" signal due to vibration of the supporting wire.
This should not be a problem unless you use a really thick heavy wire.
Thin music wire or SS fishing trace are fine, preferably in a V to prevent
the boom rotating / oscillating axially. The other main consideration is to have
a light but rigid boom. I use 1/2" nom SS water pipe with compression
fittings, but Al and fairly thin wall brass are readily available.
Put your pickup coil on the end of the boom and use a non magnetic
mass, brass or lead are fine. If you put a magnet on the boom you will see a
great number of spurious responses, mostly from transients in the utility supply
house wiring, fridges, changes in the Earth's field, movements of cars and
bikes....
Regards,
Chris Chapman
In a me=
ssage dated 10/07/06, mike8s2@......... writes:
I've been thinking of building=20=
a Lehman and was wondering what practical considerations I might run in to i=
f I significantly lengthen the boom.
Hi Mike,
Lengthen the boom to what? 2ft is about=
enough unless you want periods over 40 sec. The main considerations are the=
damping, which is far easier if you use magnet + plate damping and the bott=
om bearing. The old points and knife blades are not satisfactory and are lik=
ely to seriously limit your response. The rolling ball and the crossed cylin=
ders are fine. See http://pages.prodigy.net/fxc/ and links
Also, I've read at least one a=
ccount in which a Lehman device produced a "spurious" signal due to vibratio=
n of the supporting wire.
This should not be a problem unless you=
use a really thick heavy wire. Thin music wire or SS fishing trace are fine=
, preferably in a V to prevent the boom rotating / oscillating axially. The=20=
other main consideration is to have a light but rigid boom. I use 1/2" nom S=
S water pipe with compression fittings, but Al and fairly thin wall brass ar=
e readily available.
Put your pickup coil on the end of the=20=
boom and use a non magnetic mass, brass or lead are fine. If you put a magne=
t on the boom you will see a great number of spurious responses, mostly from=
transients in the utility supply house wiring, fridges, changes in the Eart=
h's field, movements of cars and bikes....
Regards,
Chris Chapman
Subject: Re: Help with telemetry equipment
From: Mark Robinson mark.robinson@...............
Date: Mon, 10 Jul 2006 16:19:21 +1200
ChrisAtUpw@....... wrote:
> In a message dated 08/07/06, gold1146@........... writes:
>> Does anyone on this list have schematics, internet links or know of
>> anyone selling this encoding equipment?
> As far as I know all encoders use the XR2206 function generator chip.
http://www.exar.com/product.php?ProdNumber=XR2206
It's worth measuring the temperature response of your finished oscillator.
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Help with a Lehman
From: John or Jan Lahr JohnJan@........
Date: Sun, 09 Jul 2006 22:26:58 -0700
At 08:06 PM 7/9/2006, you wrote:
> ...what practical considerations I might run in to if I
> significantly lengthen the boom.
The entire sensor must be shielded from drafts. The longer the boom,
the larger the cover
must be! For amateur seismology there is little point in trying to
achieve a period longer than 15 or 20 seconds. Tilt sensitivity will
limit the period you can achieve without frequent releveling.
John
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Updated Earthworm Modules
From: Larry Cochrane lcochrane@..............
Date: Sun, 09 Jul 2006 22:45:54 -0700
The following message was sent to the Earthworm mailing list...
Hi Everyone,
Last year I created two modules for Earthworm 6.2 and 6.3 that can be used to import
data into EW from my 16-Bit A/D board or my WinSDR datalogger using TCP/IP. These
modules have been updated to support EW Version 7.0. I also created a PSN4putaway.c
file to allow the modules that use the putaway function to save PSN Type 4 event
files. I recompiled the two modules I could find, trig2disk and waveman2disk, that
save event files in various formats to include the new event file format. They are
included in the psn4putaway.zip file.
Please see http://www.seismicnet.com/software.html#Earthworm for more information.
Regards,
Larry Cochrane
Redwood City, PSN
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Help with telemetry equipment
From: Larry Cochrane lcochrane@..............
Date: Sun, 09 Jul 2006 23:10:08 -0700
Hi Chris,
There's another problem I forgot to write about. One of the parts, a digital
band-pass filter made by Maxim, is no longer available. When I get some time I will
place the schematic of the board on my website but since one of the ICs can't be
purchased anymore it won't be too useful.
Regards,
Larry Cochrane
Redwood City, PSN
ChrisAtUpw@....... wrote:
> In a message dated 09/07/06, lcochrane@.............. writes:
>
>> You will also need to buy or build a demodulator board other then
>> mine. I no longer
>> sell my USGS Telemetry demodulator board since I never sold enough of
>> them to go into production.
>
>
> Hi Larry,
>
> In that case could you put the circuit diagram on your website,
> please?
>
> This would be most helpful.
>
> Regards,
>
> Chris Chapman
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Help with telemetry equipment
From: ChrisAtUpw@.......
Date: Mon, 10 Jul 2006 02:36:10 EDT
In a message dated 2006/07/10 , lcochrane@.............. writes:
> There's another problem I forgot to write about. One of the parts, a
> digital
> band-pass filter made by Maxim, is no longer available. When I get some time
> I will
> place the schematic of the board on my website but since one of the ICs
> can't be
> purchased anymore it won't be too useful.
Hi Larry,
Thanks. That would be great!
Maxim produced a new bandpass filter a while back, so I suspect that
there is a replacement. One of the groups monitoring the ionosphere with VLF
radio use it.
Regards,
Chris Chapman
In a me=
ssage dated 2006/07/10 , lcochrane@.............. writes:
There's another problem I forgo=
t to write about. One of the parts, a digital
band-pass filter made by Maxim, is no longer available. When I get some time=
I will
place the schematic of the board on my website but since one of the ICs can'=
t be
purchased anymore it won't be too useful.
Hi Larry,
Thanks. That would be great!
Maxim produced a new bandpass filter a=20=
while back, so I suspect that there is a replacement. One of the groups moni=
toring the ionosphere with VLF radio use it.
Regards,
Chris Chapman
Subject: Re: Help with telemetry equipment
From: ian ian@...........
Date: Mon, 10 Jul 2006 16:37:51 +0100
out of interest, what's the spec of how the data is encoded? I'm
wondering if a sound card can decode it.
Ian
ChrisAtUpw@....... wrote:
> In a message dated 2006/07/10 , lcochrane@.............. writes:
>
>> There's another problem I forgot to write about. One of the parts, a
>> digital
>> band-pass filter made by Maxim, is no longer available. When I get
>> some time I will
>> place the schematic of the board on my website but since one of the
>> ICs can't be
>> purchased anymore it won't be too useful.
>
>
>
> Hi Larry,
>
> Thanks. That would be great!
>
> Maxim produced a new bandpass filter a while back, so I suspect
> that there is a replacement. One of the groups monitoring the
> ionosphere with VLF radio use it.
>
> Regards,
>
> Chris Chapman
out of interest, what's the spec of how the data is encoded? I'm
wondering if a sound card can decode it.
Ian
ChrisAtUpw@....... wrote:
In a message dated
2006/07/10 , lcochrane@.............. writes:
There's
another problem I forgot to write about. One of the parts, a digital
band-pass filter made by Maxim, is no longer available. When I get some
time I will
place the schematic of the board on my website but since one of the ICs
can't be
purchased anymore it won't be too useful.
Hi Larry,
Thanks. That would be great!
Maxim produced a new bandpass filter a while back, so I suspect
that there is a replacement. One of the groups monitoring the
ionosphere with VLF radio use it.
Regards,
Chris Chapman
Subject: Re: Help with telemetry equipment
From: ChrisAtUpw@.......
Date: Mon, 10 Jul 2006 13:24:03 EDT
In a message dated 10/07/06, ian@........... writes:
> out of interest, what's the spec of how the data is encoded? I'm wondering
> if a sound card can decode it.
Hi Ian,
It is sent as a narrow band sine wave tone. The channel separation is
only 340 Hz. For the center frequencies see
http://psn.quake.net/onlinedocs/demoddoc.html
Hence the need for a precision encoder like the XR2206.
Does a sound card to have a stability in the low ppm range?
Regards,
Chris Chapman
In a me=
ssage dated 10/07/06, ian@........... writes:
out of interest, what's the spe=
c of how the data is encoded? I'm wondering if a sound card can decode=
it.
Hi Ian,
It is sent as a narrow band sine wave t=
one. The channel separation is only 340 Hz. For the center frequencies see h=
ttp://psn.quake.net/onlinedocs/demoddoc.html
Hence the need for a precision encoder like the XR2206.
Does a sound card to have a stability i=
n the low ppm range?
Regards,
Chris Chapman
Subject: Re: Help with telemetry equipment
From: ian ian@...........
Date: Tue, 11 Jul 2006 06:02:30 +0100
Hi,
thanks for the link. I wasn't able to deduce from that page how the
encoding/decoding works (call me dumb!). Is there any other web page
that would explain it?
I note your comment about stability. Will your average radio have
similar stability or does the encoding method mean that that isn't an issue?
Thanks
Ian
ChrisAtUpw@....... wrote:
> In a message dated 10/07/06, ian@........... writes:
>
>> out of interest, what's the spec of how the data is encoded? I'm
>> wondering if a sound card can decode it.
>
>
>
> Hi Ian,
>
> It is sent as a narrow band sine wave tone. The channel
> separation is only 340 Hz. For the center frequencies see
> http://psn.quake.net/onlinedocs/demoddoc.html
> Hence the need for a precision encoder like the XR2206.
> Does a sound card to have a stability in the low ppm range?
>
> Regards,
>
> Chris Chapman
Hi,
thanks for the link. I wasn't able to deduce from that page how the
encoding/decoding works (call me dumb!). Is there any other web page
that would explain it?
I note your comment about stability. Will your average radio have
similar stability or does the encoding method mean that that isn't an
issue?
Thanks
Ian
ChrisAtUpw@....... wrote:
In a message dated
10/07/06, ian@........... writes:
out
of interest, what's the spec of how the data is encoded? I'm wondering
if a sound card can decode it.
Hi Ian,
It is sent as a narrow band sine wave tone. The channel
separation is only 340 Hz. For the center frequencies see
http://psn.quake.net/onlinedocs/demoddoc.html
Hence the need for a precision encoder like the XR2206.
Does a sound card to have a stability in the low ppm range?
Regards,
Chris Chapman
Subject: Re: Help with telemetry equipment
From: "James Hannon" jmhannon@.........
Date: Tue, 11 Jul 2006 07:39:37 -0500
I would expect that a sound card would be stable enough to decode the telemetry signals. All the cards I have seen use a crystal for the reference frequency. As long as the temperature of the card doesn't vary over a wide range you will be ok. The real question is: Is there software avaliable to do the demodulation?
As far as the radio stability is concerned: The signals are transmitted as FM so a slight mistuning of the radio will not affect the frequency of the tones.
Jim Hannon
---------- Original Message ----------------------------------
From: ian
Reply-To: psn-l@..............
Date: Tue, 11 Jul 2006 06:02:30 +0100
>Hi,
>
>thanks for the link. I wasn't able to deduce from that page how the
>encoding/decoding works (call me dumb!). Is there any other web page
>that would explain it?
>
>I note your comment about stability. Will your average radio have
>similar stability or does the encoding method mean that that isn't an issue?
>
>Thanks
>
>Ian
>
>ChrisAtUpw@....... wrote:
>
>> In a message dated 10/07/06, ian@........... writes:
>>
>>> out of interest, what's the spec of how the data is encoded? I'm
>>> wondering if a sound card can decode it.
>>
>>
>>
>> Hi Ian,
>>
>> It is sent as a narrow band sine wave tone. The channel
>> separation is only 340 Hz. For the center frequencies see
>> http://psn.quake.net/onlinedocs/demoddoc.html
>> Hence the need for a precision encoder like the XR2206.
>> Does a sound card to have a stability in the low ppm range?
>>
>> Regards,
>>
>> Chris Chapman
>
>
>
>
--
Jim Hannon
http://www.fmtcs.com/web/jmhannon/
42,11.90N,91,39.26W
WB0TXL
--
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Subject: Re: Help with telemetry equipment
From: Ian Smith ian@...........
Date: Tue, 11 Jul 2006 13:44:17 +0100
Hi,
labview has some great demodulation software built into it as well as
software to interface with sound cards. That's what I was thinking of
when I wondered how the signal was encoded. Still wondering...
Cheers
Ian
James Hannon wrote:
>I would expect that a sound card would be stable enough to decode the telemetry signals. All the cards I have seen use a crystal for the reference frequency. As long as the temperature of the card doesn't vary over a wide range you will be ok. The real question is: Is there software avaliable to do the demodulation?
>
>As far as the radio stability is concerned: The signals are transmitted as FM so a slight mistuning of the radio will not affect the frequency of the tones.
>
>Jim Hannon
>
>---------- Original Message ----------------------------------
>From: ian
>Reply-To: psn-l@..............
>Date: Tue, 11 Jul 2006 06:02:30 +0100
>
>
>
>>Hi,
>>
>>thanks for the link. I wasn't able to deduce from that page how the
>>encoding/decoding works (call me dumb!). Is there any other web page
>>that would explain it?
>>
>>I note your comment about stability. Will your average radio have
>>similar stability or does the encoding method mean that that isn't an issue?
>>
>>Thanks
>>
>>Ian
>>
>>ChrisAtUpw@....... wrote:
>>
>>
>>
>>>In a message dated 10/07/06, ian@........... writes:
>>>
>>>
>>>
>>>>out of interest, what's the spec of how the data is encoded? I'm
>>>>wondering if a sound card can decode it.
>>>>
>>>>
>>>
>>>Hi Ian,
>>>
>>> It is sent as a narrow band sine wave tone. The channel
>>>separation is only 340 Hz. For the center frequencies see
>>>http://psn.quake.net/onlinedocs/demoddoc.html
>>>Hence the need for a precision encoder like the XR2206.
>>> Does a sound card to have a stability in the low ppm range?
>>>
>>> Regards,
>>>
>>> Chris Chapman
>>>
>>>
>>
>>
>>
>>
>
>--
>Jim Hannon
>http://www.fmtcs.com/web/jmhannon/
>42,11.90N,91,39.26W
>WB0TXL
>--
>__________________________________________________________
>
>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,
labview has some great demodulation software built into it as well as software
to interface with sound cards. That's what I was thinking of when I wondered
how the signal was encoded. Still wondering...
Cheers
Ian
James Hannon wrote:
I would expect that a sound card would be stable enough to decode the telemetry signals. All the cards I have seen use a crystal for the reference frequency. As long as the temperature of the card doesn't vary over a wide range you will be ok. The real question is: Is there software avaliable to do the demodulation?
As far as the radio stability is concerned: The signals are transmitted as FM so a slight mistuning of the radio will not affect the frequency of the tones.
Jim Hannon
---------- Original Message ----------------------------------
From: ian <ian@...........>
Reply-To: psn-l@..............
Date: Tue, 11 Jul 2006 06:02:30 +0100
Hi,
thanks for the link. I wasn't able to deduce from that page how the
encoding/decoding works (call me dumb!). Is there any other web page
that would explain it?
I note your comment about stability. Will your average radio have
similar stability or does the encoding method mean that that isn't an issue?
Thanks
Ian
ChrisAtUpw@....... wrote:
In a message dated 10/07/06, ian@........... writes:
out of interest, what's the spec of how the data is encoded? I'm
wondering if a sound card can decode it.
Hi Ian,
It is sent as a narrow band sine wave tone. The channel
separation is only 340 Hz. For the center frequencies see
http://psn.quake.net/onlinedocs/demoddoc.html
Hence the need for a precision encoder like the XR2206.
Does a sound card to have a stability in the low ppm range?
Regards,
Chris Chapman
--
Jim Hannon
http://www.fmtcs.com/web/jmhannon/
42,11.90N,91,39.26W
WB0TXL
--
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To leave this list email PSN-L-REQUEST@.............. with
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Subject: Re: Help with telemetry equipment
From: "Wayne Abraham" gold1146@...........
Date: Tue, 11 Jul 2006 13:05:22 +0000
Larry
Sad to hear that you are no longer making the telemetry decoder board. It
puts my plans on indefinite hold. I have one of them and have always seen
the need for purchasing a few more but my only drawback was the telemetry
encoder as there is only one telemetered site close to my home. I am a bit
surprised that many of these boards were not sold. How do other psn members
locate local or regional quakes?
I hope that someone can take up on where you left and not only build a
telemetry decoder for sale, but also an encoder.
Wayne
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Subject: Re: Help with telemetry equipment
From: "James Hannon" jmhannon@.........
Date: Tue, 11 Jul 2006 08:05:36 -0500
Each radio signal can transmit up to 8 channels of data. Each channel is assigned a center frequency per the chart below. To send data a tone either 125 Hz above the center frequency or 125 Hz below the center frequency is transmitted. A logic one or zero is signified by the tone being above or below the center frequency. Don't know which. I also have yet to find the bit rate or the exact format of the data being sent. I remember having it all figured out some years ago but can't remember. It seems from Larry's information the data is sampled to 12 bits.
Channel Center freq
1 680 Hz
2 1020 Hz
3 1360 Hz
4 1700 Hz
5 2040 Hz
6 2380 Hz
7 2720 Hz
8 3060 Hz
In looking for information I found this site that offers software to do the decoding with a sound card, not free but:
http://www.geotool.com/geoseis.htm
Jim Hannon
---------- Original Message ----------------------------------
From: Ian Smith
Reply-To: psn-l@..............
Date: Tue, 11 Jul 2006 13:44:17 +0100
>Hi,
>
>labview has some great demodulation software built into it as well as
>software to interface with sound cards. That's what I was thinking of
>when I wondered how the signal was encoded. Still wondering...
>
>Cheers
>
>Ian
>
>James Hannon wrote:
>
>>I would expect that a sound card would be stable enough to decode the telemetry signals. All the cards I have seen use a crystal for the reference frequency. As long as the temperature of the card doesn't vary over a wide range you will be ok. The real question is: Is there software avaliable to do the demodulation?
>>
>>As far as the radio stability is concerned: The signals are transmitted as FM so a slight mistuning of the radio will not affect the frequency of the tones.
>>
>>Jim Hannon
>>
>>---------- Original Message ----------------------------------
>>From: ian
>>Reply-To: psn-l@..............
>>Date: Tue, 11 Jul 2006 06:02:30 +0100
>>
>>
>>
>>>Hi,
>>>
>>>thanks for the link. I wasn't able to deduce from that page how the
>>>encoding/decoding works (call me dumb!). Is there any other web page
>>>that would explain it?
>>>
>>>I note your comment about stability. Will your average radio have
>>>similar stability or does the encoding method mean that that isn't an issue?
>>>
>>>Thanks
>>>
>>>Ian
>>>
>>>ChrisAtUpw@....... wrote:
>>>
>>>
>>>
>>>>In a message dated 10/07/06, ian@........... writes:
>>>>
>>>>
>>>>
>>>>>out of interest, what's the spec of how the data is encoded? I'm
>>>>>wondering if a sound card can decode it.
>>>>>
>>>>>
>>>>
>>>>Hi Ian,
>>>>
>>>> It is sent as a narrow band sine wave tone. The channel
>>>>separation is only 340 Hz. For the center frequencies see
>>>>http://psn.quake.net/onlinedocs/demoddoc.html
>>>>Hence the need for a precision encoder like the XR2206.
>>>> Does a sound card to have a stability in the low ppm range?
>>>>
>>>> Regards,
>>>>
>>>> Chris Chapman
>>>>
>>>>
>>>
>>>
>>>
>>>
>>
>>--
>>Jim Hannon
>>http://www.fmtcs.com/web/jmhannon/
>>42,11.90N,91,39.26W
>>WB0TXL
>>--
>>__________________________________________________________
>>
>>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.
>>
>>
>>
>>
>
>--
>
>
>
>
--
Jim Hannon
http://www.fmtcs.com/web/jmhannon/
42,11.90N,91,39.26W
WB0TXL
--
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Subject: Re: Help with telemetry equipment
From: "Jerry Payton" gpayton880@.......
Date: Tue, 11 Jul 2006 08:19:58 -0500
With all this discussion about telemetery data, how would I find out if
there is a transmitting station near my location? Is there a URL with the
information?
Thanks,
Jerry Payton
With all this discussion about telemetery data, how would I find =
out if=20
there is a transmitting station near my location? Is there a URL =
with the=20
information?
Thanks,
Jerry Payton
Subject: Re: Help with telemetry equipment
From: "James Hannon" jmhannon@.........
Date: Tue, 11 Jul 2006 08:29:14 -0500
OOPS.
I did some more reading of the geotools site and realized that I made a bad assumption about the data format. The information is transmitted in an analog format not digital. So the tone is simply FM modulated with the amplitude of the output from the seismograph. This means that if there is no movement of the seismograph you will see a tone at the center frequency of the channel. The frequency of the tone will follow the level of the seismograph signal up and down within the limits of +/- 125 Hz. Full scale + volts would be a tone 125 Hz greater than the center frequency and full scale - volts would be a tone 125 Hz less than the center frequency.
Jim Hannon
--
Jim Hannon
http://www.fmtcs.com/web/jmhannon/
42,11.90N,91,39.26W
WB0TXL
--
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Subject: Re: Help with telemetry equipment
From: Ian Smith ian@...........
Date: Tue, 11 Jul 2006 14:53:00 +0100
so for 12 bits bipolar, that's about a 1/16th of a Hz per data number.
Hmm... I'll have a look at the sound card spec sometime.
Thanks
Ian
James Hannon wrote:
>OOPS.
>I did some more reading of the geotools site and realized that I made a bad assumption about the data format. The information is transmitted in an analog format not digital. So the tone is simply FM modulated with the amplitude of the output from the seismograph. This means that if there is no movement of the seismograph you will see a tone at the center frequency of the channel. The frequency of the tone will follow the level of the seismograph signal up and down within the limits of +/- 125 Hz. Full scale + volts would be a tone 125 Hz greater than the center frequency and full scale - volts would be a tone 125 Hz less than the center frequency.
>
>Jim Hannon
>
>--
>Jim Hannon
>http://www.fmtcs.com/web/jmhannon/
>42,11.90N,91,39.26W
>WB0TXL
>--
>__________________________________________________________
>
>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.
>
>
>
>
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Subject: ebay auctions
From: Bob Barns royb1@...........
Date: Tue, 11 Jul 2006 10:07:21 -0400
Hi gang,
2 ebay auctions
W.F. Sprengnether Seismometer ATC-T/M-8
Item number: 250006564657
ends July 17
W.F. Sprengnether Seismometer ATC-T/M-8
Item number: 250006564657
ends July 17
Bob
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Subject: Re: ebay auctions
From: =?ISO-8859-1?Q?J=F3n_Fr=EDmann?= jonfr500@.........
Date: Tue, 11 Jul 2006 14:29:48 +0000
Hi Bob
Both item that you list in your email have the same ID.
Regards.
--
Jón Frímann
http://www.jonfr.com
http://www.simnet.is/jonfr500/earthquake/
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Public Seismic Network Mailing List (PSN-L)
Subject: Re: Help with telemetry equipment
From: ChrisAtUpw@.......
Date: Tue, 11 Jul 2006 10:37:32 EDT
In a message dated 11/07/06, jmhannon@......... writes:
> Each radio signal can transmit up to 8 channels of data. Each channel is
> assigned a center frequency per the chart below. To send data a tone either 125
> Hz above the center frequency or 125 Hz below the center frequency is
> transmitted. A logic one or zero is signified by the tone being above or below the
> center frequency.
Hi Jim,
http://www.geotool.com/geoseis.htm
> This exciting new computer program uses any good quality scanner radio to
> demodulate standard and non-standard telemetry frequencies. The sound card in
> your computer converts the telemetry tone to digital information. The program
> runs under Windows 98, and is anticipated to provide 12 to 16 bit data from
> the telemetry signal. We are truly excited about the breakthrough sound card
> programming technology provided by Silicon Pixels.
Some links were narrow band modulation using the actual seismic signal
and FM modulation, not a digital signal with FSK tones. Hence the 20 ppm
stability of the XR2206. Which critter are we talking about?
Regards,
Chris Chapman
In a me=
ssage dated 11/07/06, jmhannon@......... writes:
Each radio signal can transmit=20=
up to 8 channels of data. Each channel is assigned a center frequency per th=
e chart below. To send data a tone either 125 Hz above the center frequency=20=
or 125 Hz below the center frequency is transmitted. A logic one or zero is=20=
signified by the tone being above or below the center frequency.
Hi Jim,
http://www.geotool.com/geoseis.htm
This exciting new computer prog=
ram uses any good quality scanner radio to demodulate standard and non-stand=
ard telemetry frequencies. The sound card in your computer converts the t=
elemetry tone to digital information. The program runs under Windows 98,=
and is anticipated to provide 12 to 16 bit data from the telemetry signal.=20=
We are truly excited about the breakthrough sound card programming technolog=
y provided by Silicon Pixels.
Some links were narrow band modulation=20=
using the actual seismic signal and FM modulation, not a digital signal with=
FSK tones. Hence the 20 ppm stability of the XR2206. Which critter are we t=
alking about?
Regards,
Chris Chapman
Subject: Re: ebay auctions
From: Jan Froom JDarwin@.............
Date: Tue, 11 Jul 2006 08:01:41 -0700
The other one is item number 260004872887 JF
Bob Barns wrote:
> Hi gang,
> 2 ebay auctions
>
> W.F. Sprengnether Seismometer ATC-T/M-8
> Item number: 250006564657 ends July 17
>
> W.F. Sprengnether Seismometer ATC-T/M-8
> Item number: 250006564657 ends July 17
>
>
> 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.
>
>
>
The other one is item number 260004872887 JF
Bob Barns wrote:
Hi gang,
2 ebay auctions
W.F. Sprengnether Seismometer ATC-T/M-8
Item number: 250006564657 ends July 17
W.F. Sprengnether Seismometer ATC-T/M-8
Item number: 250006564657 ends July 17
Bob
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Subject: Stability of sound cards
From: "James Hannon" jmhannon@.........
Date: Tue, 11 Jul 2006 11:05:55 -0500
Sound cards use a small surface mount crystal oscillator for their reference frequency. These oscillators typically have a stability of +/- 100 ppm over a temperature range of -10C to +70C. This is +/- 0.1 Hz at 1000Hz. Which is in the same ballpark as the 0.061 Hz per step at 12 bits. However the sound card is not very likely to see such temperature variations and there are ways of digitally removing offsets and slowly varying drift from the data.
Jim Hannon
--
Jim Hannon
http://www.fmtcs.com/web/jmhannon/
42,11.90N,91,39.26W
WB0TXL
--
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Subject: Re: Stability of sound cards
From: "James L. Gundersen" jgundie@.......
Date: Tue, 11 Jul 2006 12:27:59 -0700
> Jim Hannon,
Isn't +/-100ppm +/-0.01Hz at 1000Hz?
Jim Gundersen
----- Original Message -----
From: "James Hannon"
To:
Sent: Tuesday, July 11, 2006 9:05 AM
Subject: Stability of sound cards
> Sound cards use a small surface mount crystal oscillator for their
> reference frequency. These oscillators typically have a stability of +/-
> 100 ppm over a temperature range of -10C to +70C. This is +/- 0.1 Hz at
> 1000Hz. Which is in the same ballpark as the 0.061 Hz per step at 12 bits.
> However the sound card is not very likely to see such temperature
> variations and there are ways of digitally removing offsets and slowly
> varying drift from the data.
>
>
> Jim Hannon
>
> --
> Jim Hannon
> http://www.fmtcs.com/web/jmhannon/
> 42,11.90N,91,39.26W
> WB0TXL
> --
> __________________________________________________________
>
> 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.
>
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Subject: Re: Stability of sound cards
From: "James Hannon" jmhannon@.........
Date: Tue, 11 Jul 2006 15:36:04 -0500
I sure thought I counted my zeros right. If it is even better.
Jim Hannon
---------- Original Message ----------------------------------
From: "James L. Gundersen"
Reply-To: psn-l@..............
Date: Tue, 11 Jul 2006 12:27:59 -0700
>> Jim Hannon,
>
>Isn't +/-100ppm +/-0.01Hz at 1000Hz?
>
>Jim Gundersen
>
>----- Original Message -----
>From: "James Hannon"
>To:
>Sent: Tuesday, July 11, 2006 9:05 AM
>Subject: Stability of sound cards
>
>
>> Sound cards use a small surface mount crystal oscillator for their
>> reference frequency. These oscillators typically have a stability of +/-
>> 100 ppm over a temperature range of -10C to +70C. This is +/- 0.1 Hz at
>> 1000Hz. Which is in the same ballpark as the 0.061 Hz per step at 12 bits.
>> However the sound card is not very likely to see such temperature
>> variations and there are ways of digitally removing offsets and slowly
>> varying drift from the data.
>>
>>
>> Jim Hannon
>>
>> --
>> Jim Hannon
>> http://www.fmtcs.com/web/jmhannon/
>> 42,11.90N,91,39.26W
>> WB0TXL
>> --
>> __________________________________________________________
>>
>> 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.
>
--
Jim Hannon
http://www.fmtcs.com/web/jmhannon/
42,11.90N,91,39.26W
WB0TXL
--
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Subject: RE: Stability of sound cards
From: "Keith Payea" kpayea@...........
Date: Tue, 11 Jul 2006 13:43:53 -0700
The easy way to think of it is that 100ppm is 100Hz(0.1KHz) at 1 MHz.
So, divide by 1000, and 100ppm is 0.1Hz at 1KHz.
Keith
-----Original Message-----
From: psn-l-request@.............. [mailto:psn-l-request@............... On
Behalf Of James Hannon
Sent: Tuesday, July 11, 2006 1:36 PM
To: psn-l@..............
Subject: Re: Stability of sound cards
I sure thought I counted my zeros right. If it is even better.
Jim Hannon
---------- Original Message ----------------------------------
From: "James L. Gundersen"
Reply-To: psn-l@..............
Date: Tue, 11 Jul 2006 12:27:59 -0700
>> Jim Hannon,
>
>Isn't +/-100ppm +/-0.01Hz at 1000Hz?
>
>Jim Gundersen
>
>----- Original Message -----
>From: "James Hannon"
>To:
>Sent: Tuesday, July 11, 2006 9:05 AM
>Subject: Stability of sound cards
>
>
>> Sound cards use a small surface mount crystal oscillator for their
>> reference frequency. These oscillators typically have a stability of +/-
>> 100 ppm over a temperature range of -10C to +70C. This is +/- 0.1 Hz at
>> 1000Hz. Which is in the same ballpark as the 0.061 Hz per step at 12
bits.
>> However the sound card is not very likely to see such temperature
>> variations and there are ways of digitally removing offsets and slowly
>> varying drift from the data.
>>
>>
>> Jim Hannon
>>
>> --
>> Jim Hannon
>> http://www.fmtcs.com/web/jmhannon/
>> 42,11.90N,91,39.26W
>> WB0TXL
>> --
>> __________________________________________________________
>>
>> 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.
>
--
Jim Hannon
http://www.fmtcs.com/web/jmhannon/
42,11.90N,91,39.26W
WB0TXL
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Subject: RE: Stability of sound cards
From: "Jack Ivey" ivey@..........
Date: Tue, 11 Jul 2006 17:48:18 -0400
>Isn't +/-100ppm +/-0.01Hz at 1000Hz?
100 ppm is 0.0001. 0.0001*1000 Hz =3D 0.1 Hz
The other issue with some sound cards has to do with the sample rate
not being uniform due to hardware limitations (poor design). That=20
would show up as noise on the output in this case. There are DSP-type=20
radio receivers out there that use sound cards for digitization, but=20
they choose their sound cards carefully.
Despite all that, I'll bet you can demodulate something that looks
very like a seismic signal with any old sound card and some=20
effort. =20
Jack
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Subject: Re: Help with telemetry equipment
From: Larry Cochrane lcochrane@..............
Date: Tue, 11 Jul 2006 18:32:24 -0700
Jerry,
There probably aren't any stations you could receive in your area. You would need to
check with a local University or other agency that would run a local seismic network.
Most stations are now digital with a direct link to a geostationary satellite or
point to point microwave link, so you can't intercept the signal very easily.
Regards,
Larry Cochrane
Redwood City, PSN
Jerry Payton wrote:
> With all this discussion about telemetery data, how would I find out if
> there is a transmitting station near my location? Is there a URL with
> the information?
>
> Thanks,
> Jerry Payton
__________________________________________________________
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Subject: Re: Help with telemetry equipment
From: Dennis Wieck dwieck@............
Date: Tue, 11 Jul 2006 20:46:23 -0500
Depends on where you are. I can hear at least four different links from
my house ( NW TN). The CERI network here (Univ of Memphis- New Madrid
fault) feeds on 220 range FM links. These then are multiplexed to the
microwave link and subcarrier on an FR radio station that feeds into
Memphis.
Dennis
Larry Cochrane wrote:
> Jerry,
>
> There probably aren't any stations you could receive in your area. You
> would need to check with a local University or other agency that would
> run a local seismic network. Most stations are now digital with a
> direct link to a geostationary satellite or point to point microwave
> link, so you can't intercept the signal very easily.
>
> Regards,
> Larry Cochrane
> Redwood City, PSN
>
> Jerry Payton wrote:
>
>> With all this discussion about telemetery data, how would I find out
>> if there is a transmitting station near my location? Is there a URL
>> with the information?
>>
>> Thanks,
>> Jerry Payton
>
>
> __________________________________________________________
>
> 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.
>
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Subject: Re: Help with telemetry equipment
From: "Jerry Payton" gpayton880@.......
Date: Tue, 11 Jul 2006 20:53:14 -0500
I am in Springdale, AR. That probably is too far.
What frequency do you hear them on. The New Madrid activity was the only
signal that I thought I "might" hear with directional antennas. I'll have
to check with the U. of AR in Fayetteville.
Thank you both for input.
Jerry
----- Original Message -----
From: Dennis Wieck
To: psn-l@..............
Sent: Tuesday, July 11, 2006 8:46 PM
Subject: Re: Help with telemetry equipment
Depends on where you are. I can hear at least four different links from
my house ( NW TN). The CERI network here (Univ of Memphis- New Madrid
fault) feeds on 220 range FM links. These then are multiplexed to the
microwave link and subcarrier on an FR radio station that feeds into
Memphis.
Dennis
Larry Cochrane wrote:
> Jerry,
>
> There probably aren't any stations you could receive in your area. You
> would need to check with a local University or other agency that would
> run a local seismic network. Most stations are now digital with a
> direct link to a geostationary satellite or point to point microwave
> link, so you can't intercept the signal very easily.
>
> Regards,
> Larry Cochrane
> Redwood City, PSN
>
> Jerry Payton wrote:
>
>> With all this discussion about telemetery data, how would I find out
>> if there is a transmitting station near my location? Is there a URL
>> with the information?
>>
>> Thanks,
>> Jerry Payton
>
>
> __________________________________________________________
>
> 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
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I am in Springdale, AR. That probably is too far.
What frequency do you hear them on. The New =
Madrid=20
activity was the only signal that I thought I "might" hear =
with=20
directional antennas. I'll have to check with the U. of AR in=20
Fayetteville.
Thank you both for input.
Jerry
----- Original Message -----
From:=20
Dennis=20
Wieck
Sent: Tuesday, July 11, 2006 =
8:46=20
PM
Subject: Re: Help with =
telemetry=20
equipment
Depends on where you are. I can hear at least four =
different=20
links from
my house ( NW TN). The CERI network here (Univ of =
Memphis- New=20
Madrid
fault) feeds on 220 range FM links. These then are =
multiplexed to=20
the
microwave link and subcarrier on an FR radio station that =
feeds into=20
Memphis.
Dennis
Larry Cochrane =
wrote:
>=20
Jerry,
>
> There probably aren't any stations you could =
receive in=20
your area. You
> would need to check with a local University or =
other=20
agency that would
> run a local seismic network. Most =
stations=20
are now digital with a
> direct link to a geostationary =
satellite or=20
point to point microwave
> link, so you can't intercept the =
signal very=20
easily.
>
> Regards,
> Larry Cochrane
> =
Redwood City,=20
PSN
>
> Jerry Payton wrote:
>
>> With all =
this=20
discussion about telemetery data, how would I find out
>> if =
there=20
is a transmitting station near my location? Is there a URL =
>>=20
with the information?
>>
>> =
Thanks,
>> Jerry=20
Payton
>
>
>=20
=
__________________________________________________________
>
>=
;=20
Public Seismic Network Mailing List (PSN-L)
>
> To leave =
this list=20
email PSN-L-REQUEST@...............
=20
with the body of
> the message (first line only): =
unsubscribe
>=20
See http://www.seismicnet.co=
m/maillist.html=20
for more=20
=
information.
>
_____________________________________________=
_____________
Public=20
Seismic Network Mailing List (PSN-L)
To leave this list email =
PSN-L-REQUEST@...............
=20
with
the body of the message (first line only): unsubscribe
See =
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m/maillist.html=20
for more information.
Subject: Re: Help with telemetry equipment
From: ChrisAtUpw@.......
Date: Tue, 11 Jul 2006 23:51:48 EDT
In a message dated 12/07/06, gpayton880@....... writes:
> What frequency do you hear them on.
Hi Jerry,
Go to http://www.geotool.com/geoseis.htm and follow the links. They
are in USGS but take some finding.
Regards,
Chris Chapman
In a me=
ssage dated 12/07/06, gpayton880@....... writes:
What frequency do you hear t=
hem on.
Hi Jerry,
Go to http://www.geotool.com/geoseis.ht=
m and follow the links. They are in USGS but take some finding.
Regards,
Chris Chapman
Subject: RE: Digest from 07/11/2006 00:00:42
From: "Wayne Abraham" gold1146@...........
Date: Wed, 12 Jul 2006 12:38:32 +0000
Hello Jerry
Take a look at this site:
http://gldss7.cr.usgs.gov/neis/station_book/
Wayne
>With all this discussion about telemetery data, how would I find out if
>there is a transmitting station near my location? Is there a URL with the
>information?
>
>Thanks,
>Jerry Payton
_________________________________________________________________
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Subject: Re: Help with telemetry equipment
From: "Wayne Abraham" gold1146@...........
Date: Wed, 12 Jul 2006 20:12:30 +0000
Hell all
As we are all looking at telemetry equipment and design, can the experts on
this look at this document and let me know if it is worth anything?
http://www.pnsn.org/SHOP/MCVCO/blkdes.html
Wayne
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Subject: Re: Help with telemetry equipment
From: John or Jan Lahr JohnJan@........
Date: Wed, 12 Jul 2006 16:53:23 -0700
This is the design that was used by the UW and by the Alaska Volcano
Observatory in
the late 1990's. So far as I know, the design worked very
well. Newer stations are
generally all digital and broad band. I assume that many stations
are still using the VCO
technology for regional earthquake monitoring, as the cost is
probably an order of
magnitude less.
Cheers,
John
At 01:12 PM 7/12/2006, you wrote:
>Hell all
>
>As we are all looking at telemetry equipment and design, can the
>experts on this look at this document and let me know if it is worth
>anything? http://www.pnsn.org/SHOP/MCVCO/blkdes.html
>
>Wayne
>
>_________________________________________________________________
>Express yourself instantly with MSN Messenger! Download today it's
>FREE! http://messenger.msn.click-url.com/go/onm00200471ave/direct/01/
>
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>
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>
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>of the message (first line only): unsubscribe
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Subject: OT: an alternative use for a geophone
From: Nicholas Ward nicholas.ward@.........
Date: Thu, 13 Jul 2006 09:15:09 +0100
Hi,
I realise this is probably not the kind of request you get everyday and
would like to say thanks in advance for any advise you folks might be
able to offer.
Im a multimedia artist working here in ireland. I have an installation
which will be part of a music festival here in september.
http://www.electricpicnic.ie/flash.html
For the installation i have proposed to capture the sound of 10000 or
so people all jumnping in unison to the music and play it out through
small speakers situated at the far end of the festival from the main
stages. i also anticipate picking up some of the music as it is
transmitted into the ground via the mainstage (if he had ears) would
hear under the festival.
I was thinking a geophone would be the right device to capture the
sound with. Im most interested in the 20 to 1200Hz range of
frequencies.
I have no experience with this type of equipment and was hoping you
might be able to advise me on a suitable device for this project? Also
what type of amplification would i need to bring the output signal up
to a line level, (around 100mV).
Any advise such as whether a geophone would be sensitive across this
frequency range, where i might get one, how much they cost etc that
could be offered would be really great.
Many thanks
Nicholas
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: OT: an alternative use for a geophone
From: Mark Robinson mark.robinson@...............
Date: Thu, 13 Jul 2006 20:46:51 +1200
Nicholas Ward wrote:
> Hi,
> I realise this is probably not the kind of request you get everyday and
> would like to say thanks in advance for any advise you folks might be
> able to offer.
>
> Im a multimedia artist working here in ireland. I have an installation
> which will be part of a music festival here in september.
>
> http://www.electricpicnic.ie/flash.html
>
> For the installation i have proposed to capture the sound of 10000 or so
> people all jumnping in unison to the music and play it out through small
> speakers situated at the far end of the festival from the main stages. i
> also anticipate picking up some of the music as it is transmitted into
> the ground via the mainstage (if he had ears) would hear under the
> festival.
>
> I was thinking a geophone would be the right device to capture the sound
> with. Im most interested in the 20 to 1200Hz range of frequencies.
>
> I have no experience with this type of equipment and was hoping you
> might be able to advise me on a suitable device for this project? Also
> what type of amplification would i need to bring the output signal up to
> a line level, (around 100mV).
>
> Any advise such as whether a geophone would be sensitive across this
> frequency range, where i might get one, how much they cost etc that
> could be offered would be really great.
>
> Many thanks
>
> Nicholas
Hi Nicholas,
Geophones are well suited to your application although there are some pitfalls.
They would be unlikely to capture much above about 100Hz. Ground doesn't
transmit such frequencies well anyway.
A geophone will do a good job of capturing vibrations in the ground and yes the
effects are interesting through a *large* PA. It gives the whole venue more
"feel". You can connect it straight into the microphone input of a sound desk
and get excellent results.
Small speakers will not give good results as the frequencies you are dealing
with are very low.
You could feed the geophone signal through a music synthesizer to generate a
signal in the audible spectrum.
Most oil exploration companies and university geophysics departments will have
some. Larry's for sale list at http://psn.quake.net/geophone/index.html seems
to say he has none in stock. http://www.tenrats.org/geo.shtml lists possible
sources.
cheers
Mark
__________________________________________________________
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Subject: Re: OT: an alternative use for a geophone
From: james fisher kd6iwd@.........
Date: Thu, 13 Jul 2006 02:10:22 -0700 (PDT)
Hi, a piezo disk will pick up the higher frequencies
you are interested in. use a 100 gram weight on top of
the piezo disk and bury in a 1' deep hole to isolate
disc from direct sound pickup. Superglue a strong
magnet to disk and stick on a iron rod driven into the
ground. Insulate everything well. See past posts on
piezo disks. They really work well for picking up
seismic waves as well as sound waves.
Besr Regards
Jim
--- Mark Robinson
wrote:
> Nicholas Ward wrote:
> > Hi,
> > I realise this is probably not the kind of request
> you get everyday and
> > would like to say thanks in advance for any advise
> you folks might be
> > able to offer.
> >
> > Im a multimedia artist working here in ireland. I
> have an installation
> > which will be part of a music festival here in
> september.
> >
> > http://www.electricpicnic.ie/flash.html
> >
> > For the installation i have proposed to capture
> the sound of 10000 or so
> > people all jumnping in unison to the music and
> play it out through small
> > speakers situated at the far end of the festival
> from the main stages. i
> > also anticipate picking up some of the music as it
> is transmitted into
> > the ground via the mainstage (if he had ears)
> would hear under the
> > festival.
> >
> > I was thinking a geophone would be the right
> device to capture the sound
> > with. Im most interested in the 20 to 1200Hz range
> of frequencies.
> >
> > I have no experience with this type of equipment
> and was hoping you
> > might be able to advise me on a suitable device
> for this project? Also
> > what type of amplification would i need to bring
> the output signal up to
> > a line level, (around 100mV).
> >
> > Any advise such as whether a geophone would be
> sensitive across this
> > frequency range, where i might get one, how much
> they cost etc that
> > could be offered would be really great.
> >
> > Many thanks
> >
> > Nicholas
>
> Hi Nicholas,
>
> Geophones are well suited to your application
> although there are some pitfalls.
>
> They would be unlikely to capture much above about
> 100Hz. Ground doesn't
> transmit such frequencies well anyway.
>
> A geophone will do a good job of capturing
> vibrations in the ground and yes the
> effects are interesting through a *large* PA. It
> gives the whole venue more
> "feel". You can connect it straight into the
> microphone input of a sound desk
> and get excellent results.
>
> Small speakers will not give good results as the
> frequencies you are dealing
> with are very low.
>
> You could feed the geophone signal through a music
> synthesizer to generate a
> signal in the audible spectrum.
>
> Most oil exploration companies and university
> geophysics departments will have
> some. Larry's for sale list at
> http://psn.quake.net/geophone/index.html seems
> to say he has none in stock.
> http://www.tenrats.org/geo.shtml lists possible
> sources.
>
> cheers
> Mark
>
>
__________________________________________________________
>
> 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.
>
__________________________________________________________
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Subject: Re: OT: an alternative use for a geophone
From: Nicholas Ward nicholas.ward@.........
Date: Thu, 13 Jul 2006 10:36:19 +0100
Great,
Thanks for the info.
N
On 13 Jul 2006, at 10:10, james fisher wrote:
> Hi, a piezo disk will pick up the higher frequencies
> you are interested in. use a 100 gram weight on top of
> the piezo disk and bury in a 1' deep hole to isolate
> disc from direct sound pickup. Superglue a strong
> magnet to disk and stick on a iron rod driven into the
> ground. Insulate everything well. See past posts on
> piezo disks. They really work well for picking up
> seismic waves as well as sound waves.
>
> Besr Regards
>
> Jim
>
> --- Mark Robinson
> wrote:
>
>> Nicholas Ward wrote:
>>> Hi,
>>> I realise this is probably not the kind of request
>> you get everyday and
>>> would like to say thanks in advance for any advise
>> you folks might be
>>> able to offer.
>>>
>>> Im a multimedia artist working here in ireland. I
>> have an installation
>>> which will be part of a music festival here in
>> september.
>>>
>>> http://www.electricpicnic.ie/flash.html
>>>
>>> For the installation i have proposed to capture
>> the sound of 10000 or so
>>> people all jumnping in unison to the music and
>> play it out through small
>>> speakers situated at the far end of the festival
>> from the main stages. i
>>> also anticipate picking up some of the music as it
>> is transmitted into
>>> the ground via the mainstage (if he had ears)
>> would hear under the
>>> festival.
>>>
>>> I was thinking a geophone would be the right
>> device to capture the sound
>>> with. Im most interested in the 20 to 1200Hz range
>> of frequencies.
>>>
>>> I have no experience with this type of equipment
>> and was hoping you
>>> might be able to advise me on a suitable device
>> for this project? Also
>>> what type of amplification would i need to bring
>> the output signal up to
>>> a line level, (around 100mV).
>>>
>>> Any advise such as whether a geophone would be
>> sensitive across this
>>> frequency range, where i might get one, how much
>> they cost etc that
>>> could be offered would be really great.
>>>
>>> Many thanks
>>>
>>> Nicholas
>>
>> Hi Nicholas,
>>
>> Geophones are well suited to your application
>> although there are some pitfalls.
>>
>> They would be unlikely to capture much above about
>> 100Hz. Ground doesn't
>> transmit such frequencies well anyway.
>>
>> A geophone will do a good job of capturing
>> vibrations in the ground and yes the
>> effects are interesting through a *large* PA. It
>> gives the whole venue more
>> "feel". You can connect it straight into the
>> microphone input of a sound desk
>> and get excellent results.
>>
>> Small speakers will not give good results as the
>> frequencies you are dealing
>> with are very low.
>>
>> You could feed the geophone signal through a music
>> synthesizer to generate a
>> signal in the audible spectrum.
>>
>> Most oil exploration companies and university
>> geophysics departments will have
>> some. Larry's for sale list at
>> http://psn.quake.net/geophone/index.html seems
>> to say he has none in stock.
>> http://www.tenrats.org/geo.shtml lists possible
>> sources.
>>
>> cheers
>> Mark
>>
>>
> __________________________________________________________
>>
>> 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.
>
__________________________________________________________
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Subject: Re: OT: an alternative use for a geophone
From: ChrisAtUpw@.......
Date: Thu, 13 Jul 2006 09:42:21 EDT
In a message dated 13/07/06, nicholas.ward@......... writes:
> Great,
> Thanks for the info.
> N
>
> On 13 Jul 2006, at 10:10, james fisher wrote:
>
> > Hi, a piezo disk will pick up the higher frequencies
> > you are interested in. use a 100 gram weight on top of
> > the piezo disk and bury in a 1' deep hole to isolate
> > disc from direct sound pickup. Superglue a strong
> > magnet to disk and stick on a iron rod driven into the
> > ground. Insulate everything well. See past posts on
> > piezo disks. They really work well for picking up
> > seismic waves as well as sound waves.
Hi Nicolas,
You will need FET input opamp TL071? to match the high input impedance
of the piezo disk.
Superglue will not last long; a modified two part acrylic like
Holdtite ST3295 is much better. It is tough and doesn't crack.
Can you stick the head of a 3 mm brass bolt to the centre of the piezo
disk and screw a 20 gm disk of brass on top? A high weight like 100 gm is OK
for very low frequency seismic signals, but it lowers the resonance of the
disk to maybe 200 Hz.
Regards,
Chris Chapman
In a me=
ssage dated 13/07/06, nicholas.ward@......... writes:
Great,
Thanks for the info.
N
On 13 Jul 2006, at 10:10, james fisher wrote:
> Hi, a piezo disk will pick up the higher frequencies
> you are interested in. use a 100 gram weight on top of
> the piezo disk and bury in a 1' deep hole to isolate
> disc from direct sound pickup. Superglue a strong
> magnet to disk and stick on a iron rod driven into the
> ground. Insulate everything well. See past posts on
> piezo disks. They really work well for picking up
> seismic waves as well as sound waves.
Hi Nicolas,
You will need FET input opamp TL071? to=
match the high input impedance of the piezo disk.
Superglue will not last long; a modifie=
d two part acrylic like Holdtite ST3295 is much better. It is tough and does=
n't crack.
Can you stick the head of a 3 mm brass=20=
bolt to the centre of the piezo disk and screw a 20 gm disk of brass on top?=
A high weight like 100 gm is OK for very low frequency seismic signals, but=
it lowers the resonance of the disk to maybe 200 Hz.
Regards,
Chris Chapman
Subject: Re: OT: an alternative use for a geophone
From: Nicholas Ward nicholas.ward@.........
Date: Thu, 13 Jul 2006 17:57:35 +0100
this is all very useful info,
thanks again
On 13 Jul 2006, at 14:42, ChrisAtUpw@....... wrote:
> In a message dated 13/07/06, nicholas.ward@......... writes:
>
>> Great,
>> Thanks for the info.
>> N
>>
>> On 13 Jul 2006, at 10:10, james fisher wrote:
>>
>> > Hi, a piezo disk will pick up the higher frequencies
>> > you are interested in. use a 100 gram weight on top of
>> > the piezo disk and bury in a 1' deep hole to isolate
>> > disc from direct sound pickup. Superglue a strong
>> > magnet to disk and stick on a iron rod driven into the
>> > ground. Insulate everything well. See past posts on
>> > piezo disks. They really work well for picking up
>> > seismic waves as well as sound waves.
>
> Hi Nicolas,
>
> =A0=A0=A0=A0=A0=A0 You will need FET input opamp TL071? to match the =
high input=20
> impedance of the piezo disk.
> =A0=A0=A0=A0=A0=A0 Superglue will not last long; a modified two part =
acrylic like=20
> Holdtite ST3295 is much better. It is tough and doesn't crack.
> =A0=A0=A0=A0=A0=A0 Can you stick the head of a 3 mm brass bolt to the =
centre of=20
> the piezo disk and screw a 20 gm disk of brass on top? A high weight=20=
> like 100 gm is OK for very low frequency seismic signals, but it=20
> lowers the resonance of the disk to maybe 200 Hz.
>
> =A0=A0=A0=A0=A0=A0 Regards,
>
> =A0=A0=A0=A0=A0=A0 Chris Chapman
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: OT: an alternative use for a geophone
From: John or Jan Lahr JohnJan@........
Date: Thu, 13 Jul 2006 11:16:59 -0700
Nicholas,
I've posted details of Chris Chapman's piezo design here:
http://jclahr.com/science/psn/chapman/piezo/index.html
Cheers,
John
At 09:57 AM 7/13/2006, you wrote:
>From: Nicholas Ward
>Subject: Re: OT: an alternative use for a geophone
>Date: Thu, 13 Jul 2006 17:57:35 +0100
>
>this is all very useful info,
>thanks again
#################################/ John C. Lahr
################################/ Emeritus Seismologist
###############################/ U.S. Geological Survey
==========================/ Central Region Geologic Hazards Team
#############################//##############################
############################//###############################
PO Box 548 /################################
Corvallis, Oregon 97339 /##################################
Phone: (541) 758-2699 /=============================
Cell: (541) 740-4844 /###################################
Fax: (928) 569-0113 /##################################
jjpub@........ /####################################
http://jclahr.com/science/
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Using a Mac as a seismometer
From: =?ISO-8859-1?Q?J=F3n_Fr=EDmann?= jonfr500@.........
Date: Sun, 16 Jul 2006 19:06:42 +0000
Hi all
Someone did write a program to use Mac computers with internal movement
sensors as a seismometers. I doubt that this is really accure in
detecing earthquake, but the idea is good. :-)
I wonder if this program can be adjusted to be used with real
seismometers or geophones.
More info here. http://www.suitable.com/tools/seismac.html and here
http://gizmodo.com/gadgets/software/turn-your-mac-laptop-into-a-seismograph-185923.php
Regards.
--
Jón Frímann
http://www.jonfr.com
http://www.simnet.is/jonfr500/earthquake/
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Using a Mac as a seismometer
From: ChrisAtUpw@.......
Date: Sun, 16 Jul 2006 15:59:43 EDT
In a message dated 2006/07/16, jonfr500@......... writes:
> Someone did write a program to use Mac computers with internal movement
> sensors as a seismometers.
Hi Jon,
It is likely to be a strong motion sensor. I put an inexpensive design
for a piezo disk semsor on John Lahr's website.
http://jclahr.com/science/psn/index.html They cover down to below 0.5 sec and are more sensitive than 4.5
Hz geophones. The disks themselves are maybe ~$1 each, but you also need a
quiet FET input opamp. Maplins and Digikey stock suitable types.
Regards.
Chris Chapman
In a me=
ssage dated 2006/07/16, jonfr500@......... writes:
Someone did write a program to=20=
use Mac computers with internal movement
sensors as a seismometers.
Hi Jon,
It is likely to be a strong motion sens=
or. I put an inexpensive design for a piezo disk semsor on John Lahr's websi=
te. http://jclahr.com/science/psn/index.html They cover down to below 0.5 se=
c and are more sensitive than 4.5 Hz geophones. The disks themselves are may=
be ~$1 each, but you also need a quiet FET input opamp. Maplins and Digikey=20=
stock suitable types.
Regards.
Chris Chapman
Subject: Looking for a manual for a Teledyne-Geotech TG-120 Timing
From: apsn apsn@...........
Date: Sun, 16 Jul 2006 15:20:57 -0800
Hi all,
I'm looking for a manual for a Teledyne-Geotech TG-120 Timing System
to purchase, borrow, or copy.
Also, anyone need a 16-bit data acquisition PC internal board (Larry
Cochrane, WinSDR, etc)? The price is right.
regards,
Bob Hammond
Public Seismic Network - Alaska
http://apsn.awcable.com
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Public Seismic Network Mailing List (PSN-L)
Subject: Re: Help with telemetry equipment
From: wizard@.........
Date: Sun, 16 Jul 2006 16:37:59 -0700
Check out Spectrum Lab for decoding the VHF/UHF telemetry signals.
http://www.dxzone.com/cgi-bin/dir/jump2.cgi?ID=9270
It might not give you the detail needed for serious monitoring, but it will allow you to
decode and view the FM telemetry signals. I listen to 163.605 and 218.3 Mhz at my
location.
I took a look at the GeoTool program. It seems to work ok but crashes on two of my
systems, suspect they will have that fixed soon. The program does a great job of
decoding and displaying the signal.
Michael
Tuolumne CA
Date sent: Tue, 11 Jul 2006 13:44:17 +0100
From: Ian Smith
To: psn-l@..............
Subject: Re: Help with telemetry equipment
Send reply to: psn-l@..............
Hi,
labview has some great demodulation software built into it as well as software to
interface with sound cards. That's what I was thinking of when I wondered how the
signal was encoded. Still wondering...
Cheers
Ian
James Hannon wrote:
I would expect that a sound card would be stable enough to
decode the telemetry signals. All the cards I have seen use a
crystal for the reference frequency. As long as the
temperature of the card doesn't vary over a wide range you
will be ok. The real question is: Is there software avaliable
to do the demodulation?
As far as the radio stability is concerned: The signals are
transmitted as FM so a slight mistuning of the radio will not
affect the frequency of the tones.
Jim Hannon
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Using a Mac as a seismometer
From: "Connie and Jim Lehman" lehmancj@...........
Date: Mon, 17 Jul 2006 08:32:46 -0400
Jon-- I am not familiar with an internal sensor in Macs--- Your reference
to Mac computers reminds me of a standard physics lab exercise of simple
harmonic motion. Using the companion force probe mounted vertically
weighted by a spring & mass, one could get a beautiful readout of
SHM.--comparing different masses & spring constants. I forget in those days
if the probe was a Hall effect or capacitive type (Vernier Lab unit) The
setup was extremely sensitive, and we played with the idea of forming a
1-sec vertical/properly damped. As I was more interested in long period
performance I never pursued the idea further, but would be interested if
anyone tried such a design---
Have a great day--Jim Lehman
----- Original Message -----
From: "Jón Frímann"
To: "PSN-Postlist"
Sent: Sunday, July 16, 2006 3:06 PM
Subject: Using a Mac as a seismometer
> Hi all
>
> Someone did write a program to use Mac computers with internal movement
> sensors as a seismometers. I doubt that this is really accure in
> detecing earthquake, but the idea is good. :-)
>
> I wonder if this program can be adjusted to be used with real
> seismometers or geophones.
>
> More info here. http://www.suitable.com/tools/seismac.html and here
>
http://gizmodo.com/gadgets/software/turn-your-mac-laptop-into-a-seismograph-
185923.php
>
> Regards.
> --
> Jón Frímann
> http://www.jonfr.com
> http://www.simnet.is/jonfr500/earthquake/
>
> __________________________________________________________
>
> 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[2]: Using a Mac as a seismometer
From: Angel sismos@..............
Date: Mon, 17 Jul 2006 20:33:06 +0000
Hi Everyone!
I am alive and even doing email.
I just returned from a great workshop in Brazil and attended two day
of lectures by Erhard Wielandt of STS-2 fame! He makes it all seem simple.
Anyway I got to see the Seismac on a Mac working. The new mac and
other laptops have a freefall sensor that parks the harddisk head if
it senses a freefall condition. It has three axis and samples at 200
sps and and you can see people walking around the room, heavy people
anyway. Real cute but not much else.
I reference to the radio thread. At 8 kilometers I would use just the
ISM band radios (2.4 gHz or the 5.3-5.8 gHz) is there was line of
sight. It would be very easy, I do it in several places and with some
much longer shots.
Larry thanks for the work on the Earthworm modules. I will be
downloading them tonight.
Dave Nelson has been doing some great work on the FMES, we should post
things there soon.
Hi Chris, Hi Karl.
Angel
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Jawa earthquake swarm, more to come ?
From: =?ISO-8859-1?Q?J=F3n_Fr=EDmann?= jonfr500@.........
Date: Mon, 17 Jul 2006 23:23:20 +0000
Hi all
After today Jawa earthquake swarm, that had a intal earthquake of a mag
7.7 I think there might have been large change in the earth crust
pressure. The area that I have in mind is south Sumatra, where massive
energy buildup has been taking place becose of the mag 9.3 earthquake in
2004. But the south Sumatra subduction zone is on the same faultline as
South of Jawa is. The question is, is the current activite a sign about
more large earthquakes in that area.
But over the past months, there have been mag 5> earthquakes in south
part of Sumatra, but something simular did happen in northen part of
Sumatra before the mag 9.3 earthquake.
This is just my thugh on this, but the data that is appearing now don't
show any good sign in my opinion.
Regards.
--
Jón Frímann
http://www.jonfr.com
http://www.simnet.is/jonfr500/earthquake/
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Iceland Earthquake speed model
From: =?ISO-8859-1?Q?J=F3n_Fr=EDmann?= jonfr500@.........
Date: Tue, 18 Jul 2006 22:19:29 +0000
Hi all
I got the p and s wave speed model for Iceland from IMO. I am going to
try changeing it so I can use it in WinQuake, but I need a little help
on it. Since I have never done this before. I got some instructions from
Larry, but clueless as I am sometimes, it has not helped me alot.
The model can be seen here.
http://www.simnet.is/jonfr500/iceland.earthquake.model.jpg
Thanks in advance.
Regards.
--
Jón Frímann
http://www.jonfr.com
http://www.simnet.is/jonfr500/earthquake/
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: WinQuake Filtering Advice and/or Tutorial
From: "Jerry Payton" gpayton880@.......
Date: Wed, 19 Jul 2006 12:18:13 -0500
Frankly, I have been "muddling" my way around with filtering events using
WinQuake. If someone will point me to WHERE to read about filtering or give
me a brief tutorial on filtering, I'd really appreciate it. Remember,
"KISS" (keep it simple.......)
Thank you.
Jerry
Frankly, I have been "muddling" my way around with filtering events =
using=20
WinQuake. If someone will point me to WHERE to read about =
filtering or=20
give me a brief tutorial on filtering, I'd really appreciate it. =
Remember,=20
"KISS" (keep it simple.......)
Thank you.
Jerry
Subject: ebay auction
From: Bob Barns royb1@...........
Date: Thu, 20 Jul 2006 10:15:42 -0400
Hi gang,
SEISMIC TRIGGERED SEISMOGRAPH MODEL# ST-4 DALLAS ,,,,,,
Item number: 120011126885
ends July 26
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: WinQuake Filtering Advice and/or Tutorial
From: Bobhelenmcclure@.......
Date: Fri, 21 Jul 2006 17:46:28 EDT
Hi Jerry,
I design and code my own seismic digital filters, and I have yet to find
any reference that follows the "KISS" principle. The subject is highly
mathematical. I got the most help on Butterworth filter design from
_http://kwon3d.com/theory/filtering/lpass.html_
(http://kwon3d.com/theory/filtering/lpass.html)
The information there is drawn from the bible of signal processing:
Oppenheim, A.V., & Schafer, R.W. (1989). Discrete-time signal processing.
Englewood Cliffs, NJ: Prentice Hall.
You will find my program "WQFilter" for filtering WinQuake files in the
file "seismic_dataq.zip" at
_http://www.jclahr.com/science/psn/mcclure/index.html_ (http://www.jclahr.com/science/psn/mcclure/index.html)
To explore the impulse response and bandpass properties of any filter in
WinQuake or WQFilter, use "Impulse.psn" as the source file. After filtering
it, you will see the impulse response of the filter. Use WinQuake's FFT to
reveal the corresponding spectral response of the filter. This is a very useful
exercise, even if you decide not to dig deeper.
Bob McClure
Hi Jerry,
I design and code my own seismic digital filters, and I have yet=
to=20
find any reference that follows the "KISS" principle. The subject is highly=20
mathematical. I got the most help on Butterworth filter design from
http://kwon3d.com/the=
ory/filtering/lpass.html
The information there is drawn from the bible of signal=20
processing:
Oppenheim, A.V., & Schafer, R.W. (1989). Discrete-time signal=20
processing. Englewood Cliffs, NJ: Prentice Hall.
You will find my program "WQFilter" for filtering WinQuake f=
iles=20
in the file "seismic_dataq.zip" at
http://www.jcl=
ahr.com/science/psn/mcclure/index.html
To explore the impulse response and bandpass properties of any=20
filter in WinQuake or WQFilter, use "Impulse.psn" as the source file. After=20
filtering it, you will see the impulse response of the filter. Use WinQuake'=
s=20
FFT to reveal the corresponding spectral response of the filter. This is a v=
ery=20
useful exercise, even if you decide not to dig deeper.
Bob McClure
Subject: Re: WinQuake Filtering Advice and/or Tutorial
From: "Jerry Payton" gpayton880@.......
Date: Fri, 21 Jul 2006 16:52:52 -0500
Hey Thanks Bob,
You may cause my brain cells hurt, but what the heck. You know, medical
doctors say that the human brain has no nerve endings to hurt, BUT my head
sure hurts trying to think sometimes!
I'll check these out.
Jerry
----- Original Message -----
From: Bobhelenmcclure@.......
To: psn-l@..............
Sent: Friday, July 21, 2006 4:46 PM
Subject: Re: WinQuake Filtering Advice and/or Tutorial
Hi Jerry,
I design and code my own seismic digital filters, and I have yet to find
any reference that follows the "KISS" principle. The subject is highly
mathematical. I got the most help on Butterworth filter design from
http://kwon3d.com/theory/filtering/lpass.html
The information there is drawn from the bible of signal processing:
Oppenheim, A.V., & Schafer, R.W. (1989). Discrete-time signal processing.
Englewood Cliffs, NJ: Prentice Hall.
You will find my program "WQFilter" for filtering WinQuake files in the
file "seismic_dataq.zip" at
http://www.jclahr.com/science/psn/mcclure/index.html
To explore the impulse response and bandpass properties of any filter in
WinQuake or WQFilter, use "Impulse.psn" as the source file. After filtering
it, you will see the impulse response of the filter. Use WinQuake's FFT to
reveal the corresponding spectral response of the filter. This is a very
useful exercise, even if you decide not to dig deeper.
Bob McClure
Hey Thanks =
Bob,
You may cause my brain =
cells hurt,=20
but what the heck. You know, medical doctors say that the human =
brain has=20
no nerve endings to hurt, BUT my head sure hurts trying to think=20
sometimes!
I'll check these =
out.
Jerry
----- Original Message -----
From:=20
Bobhelenmcclure@....... =
Sent: Friday, July 21, 2006 =
4:46 PM
Subject: Re: WinQuake Filtering =
Advice=20
and/or Tutorial
Hi Jerry,
I design and code my own seismic digital filters, and I =
have yet=20
to find any reference that follows the "KISS" principle. The subject =
is highly=20
mathematical. I got the most help on Butterworth filter design from =
http://kwon3d.com/=
theory/filtering/lpass.html
The information there is drawn from the bible of signal=20
processing:
Oppenheim, A.V., & Schafer, R.W. (1989). Discrete-time signal =
processing. Englewood Cliffs, NJ: Prentice Hall.
You will find my program "WQFilter" for filtering =
WinQuake=20
files in the file "seismic_dataq.zip" at
http://www.=
jclahr.com/science/psn/mcclure/index.html
To explore the impulse response and bandpass properties of =
any=20
filter in WinQuake or WQFilter, use "Impulse.psn" as the source file. =
After=20
filtering it, you will see the impulse response of the filter. Use =
WinQuake's=20
FFT to reveal the corresponding spectral response of the filter. This =
is a=20
very useful exercise, even if you decide not to dig deeper.
Bob McClure
Subject: ebay auction
From: Bob Barns royb1@...........
Date: Sun, 23 Jul 2006 10:22:30 -0400
Hi gang,
Teledyne Geotech Accelerator Seismograph NOAA
Item number: 120012153383
ends July 29
I'm guessing that this a photographic film recorder from the good old
days. :-\
Bob
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: OT: an alternative use for a geophone
From: Nicholas Ward nicholas.ward@.........
Date: Wed, 26 Jul 2006 14:16:23 +0100
Hi all,
Im just getting back to this now. Im looking at building something
based on Chris Chapman's piezo design from
http://jclahr.com/science/psn/chapman/piezo/index.html
Im having trouble with the sketch however. The circuit is no problem
just the actual construction of the piezo sensor. WOuld anyone by any
chance have a clearer or more detailed drawing i could follow. I hope i
am not causing any offense to the original artist. It is simply my lack
of knowledge with these things that prevents me from understanding the
original sketch.
Thanks again
Nicholas
On 13 Jul 2006, at 19:16, John or Jan Lahr wrote:
> Nicholas,
>
> I've posted details of Chris Chapman's piezo design here:
> http://jclahr.com/science/psn/chapman/piezo/index.html
>
> Cheers,
> John
>
> At 09:57 AM 7/13/2006, you wrote:
>> From: Nicholas Ward
>> Subject: Re: OT: an alternative use for a geophone
>> Date: Thu, 13 Jul 2006 17:57:35 +0100
>>
>> this is all very useful info,
>> thanks again
>
>
> #################################/ John C. Lahr
> ################################/ Emeritus Seismologist
> ###############################/ U.S. Geological Survey
> ==========================/ Central Region Geologic Hazards Team
> #############################//##############################
> ############################//###############################
> PO Box 548
> /################################
> Corvallis, Oregon 97339
> /##################################
> Phone: (541) 758-2699 /=============================
> Cell: (541) 740-4844
> /###################################
> Fax: (928) 569-0113 /##################################
> jjpub@........
> /####################################
> http://jclahr.com/science/
>
>
> __________________________________________________________
>
> 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: OT: an alternative use for a geophone
From: "Jerry Payton" gpayton880@.......
Date: Wed, 26 Jul 2006 15:01:44 -0500
Nicholas,
I was able to save the drawing (JPG) and print it with a Photoshop type
program. It was better, but not perfect. I used Photoshop Elements, but
any such type software should help. Simply printing the drawing from the
original webpage does NOT do a good job. I can see what you mean about
deciphering the drawing. Chris may be VERY intelligent, an "artist" he is
not. (Smile)
You might try my method and get a better print.
Regards,
Jerry Payton
----- Original Message -----
From: Nicholas Ward
To: psn-l@..............
Sent: Wednesday, July 26, 2006 8:16 AM
Subject: Re: OT: an alternative use for a geophone
Hi all,
I'm just getting back to this now. I'm looking at building something
based on Chris Chapman's piezo design from
http://jclahr.com/science/psn/chapman/piezo/index.html
I'm having trouble with the sketch however. The circuit is no problem
just the actual construction of the piezo sensor. Would anyone by any
chance have a clearer or more detailed drawing I could follow. I hope I
am not causing any offense to the original artist. It is simply my lack
of knowledge with these things that prevents me from understanding the
original sketch.
Thanks again
Nicholas
On 13 Jul 2006, at 19:16, John or Jan Lahr wrote:
> Nicholas,
>
> I've posted details of Chris Chapman's piezo design here:
> http://jclahr.com/science/psn/chapman/piezo/index.html
>
> Cheers,
> John
>
> At 09:57 AM 7/13/2006, you wrote:
>> From: Nicholas Ward
>> Subject: Re: OT: an alternative use for a geophone
>> Date: Thu, 13 Jul 2006 17:57:35 +0100
>>
>> this is all very useful info,
>> thanks again
>
>
> #################################/ John C. Lahr
> ################################/ Emeritus Seismologist
> ###############################/ U.S. Geological Survey
> ==========================/ Central Region Geologic Hazards Team
> #############################//##############################
> ############################//###############################
> PO Box 548
> /################################
> Corvallis, Oregon 97339
> /##################################
> Phone: (541) 758-2699 /=============================
> Cell: (541) 740-4844
> /###################################
> Fax: (928) 569-0113 /##################################
> jjpub@........
> /####################################
> http://jclahr.com/science/
>
>
> __________________________________________________________
>
> 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.
Nicholas,
I was able to save the drawing (JPG) and print it with a Photoshop =
type=20
program. It was better, but not perfect. I used Photoshop =
Elements,=20
but any such type software should help. Simply printing the =
drawing from=20
the original webpage does NOT do a good job. I can see what you =
mean about=20
deciphering the drawing. Chris may be VERY intelligent, an =
"artist"=20
he is not. (Smile)
You might try my method and get a better print.
Regards,
Jerry Payton
----- Original Message -----
From:=20
Nicholas Ward
Sent: Wednesday, July 26, 2006 =
8:16=20
AM
Subject: Re: OT: an alternative =
use for a=20
geophone
Hi all,
I'm just getting back to this now. I'm =
looking at=20
building something
based on Chris Chapman's piezo design from =
http://jc=
lahr.com/science/psn/chapman/piezo/index.html
I'm=20
having trouble with the sketch however. The circuit is no problem =
just the=20
actual construction of the piezo sensor. Would anyone by any =
chance have a=20
clearer or more detailed drawing I could follow. I hope I
am not =
causing=20
any offense to the original artist. It is simply my lack
of =
knowledge with=20
these things that prevents me from understanding the
original=20
sketch.
Thanks again
Nicholas
On 13 Jul 2006, at =
19:16, John=20
or Jan Lahr wrote:
> Nicholas,
>
> I've posted =
details=20
of Chris Chapman's piezo design here:
> http://jc=
lahr.com/science/psn/chapman/piezo/index.html
>
>=20
Cheers,
> John
>
> At 09:57 AM 7/13/2006, you=20
wrote:
>> From: Nicholas Ward <nicholas.ward@.........>>>=20
Subject: Re: OT: an alternative use for a geophone
>> Date: =
Thu, 13=20
Jul 2006 17:57:35 +0100
>>
>> this is all very =
useful=20
info,
>> thanks again
>
>
>=20
#################################/ John C. Lahr
>=20
################################/ Emeritus Seismologist
>=20
###############################/ U.S. Geological Survey
>=20
=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D/ Central Region Geologic Hazards Team
>=20
#############################//##############################
>=20
=
############################//###############################
>&nbs=
p; =
; =
=20
PO Box 548
>=20
=
/################################
> &n=
bsp; =20
Corvallis, Oregon 97339
>=20
=
/##################################
> =
=20
Phone: (541) 758-2699=20
=
/=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D
> &n=
bsp; =20
Cell: (541) 740-4844
>=20
=
/###################################
> =
; =20
Fax: (928) 569-0113=20
=
/##################################
> =
&=
nbsp; =20
jjpub@........
>=20
=
/####################################
> &nbs=
p; =
; =
=20
http://jclahr.com/science/
>=
;
>
>=20
=
__________________________________________________________
>
>=
;=20
Public Seismic Network Mailing List (PSN-L)
>
> To leave =
this list=20
email PSN-L-REQUEST@...............
=20
with the body of
> the message (first line only): =
unsubscribe
>=20
See http://www.seismicnet.co=
m/maillist.html=20
for more=20
=
information.
>
_____________________________________________=
_____________
Public=20
Seismic Network Mailing List (PSN-L)
To leave this list email =
PSN-L-REQUEST@...............
=20
with
the body of the message (first line only): unsubscribe
See =
http://www.seismicnet.co=
m/maillist.html=20
for more information.
Subject: Re: OT: an alternative use for a geophone
From: John Popelish jpopelish@........
Date: Wed, 26 Jul 2006 18:28:51 -0400
Jerry Payton wrote:
> Nicholas Ward wrote:
> Hi all,
> I'm just getting back to this now. I'm looking at building something
> based on Chris Chapman's piezo design from
> http://jclahr.com/science/psn/chapman/piezo/index.html
> I'm having trouble with the sketch however.
(snip)
> Nicholas,
>
> I was able to save the drawing (JPG) and print it with a
> Photoshop type program. It was better, but not perfect.
(snip)
I took a crack at cleaning up and shrinking this sketch and got it
down to a 58k gif. I will be happy to email this file to anyone who
sends me a private email, asking for it.
And Chris, If you would like some drafting help making a more formal
drawing of this device, I can volunteer a bit of time. But we should
do this off list, too, since it may take a bit of help from you,
before I get everything the way you want it.
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: OT: an alternative use for a geophone
From: "Geoffrey" gmvoeth@...........
Date: Wed, 26 Jul 2006 15:43:00 -0700
Hello;
I too looked at this sketch
and after studying it found
it complex and difficult
to build. I was looking for
something much simpler with
easy to find parts.
Possibly The creator should
assemble the parts into a kit
and sell the kit but I bet it would
then not cost as cheap as you want.
It seems best to find a used professional geophone
somewhere because that is the only way
you will find one small and compact
enough to be easily transportable.
The creator of this mechanical circuit
seems quite talented and has the tenacity
to find the necessary raw materials.
If you are serious enough to recreate
this idea then I would be anxious
to hear your results in great detail.
I think Chris is the creator but not certain.
Regards;
gmvoeth
----- Original Message -----
From: "John Popelish"
To:
Sent: Wednesday, July 26, 2006 3:28 PM
Subject: Re: OT: an alternative use for a geophone
> Jerry Payton wrote:
>> Nicholas Ward wrote:
>
>> Hi all,
>> I'm just getting back to this now. I'm looking at building something
>> based on Chris Chapman's piezo design from
>> http://jclahr.com/science/psn/chapman/piezo/index.html
>> I'm having trouble with the sketch however.
> (snip)
> > Nicholas,
> >
> > I was able to save the drawing (JPG) and print it with a
> > Photoshop type program. It was better, but not perfect.
> (snip)
>
> I took a crack at cleaning up and shrinking this sketch and got it
> down to a 58k gif. I will be happy to email this file to anyone who
> sends me a private email, asking for it.
>
> And Chris, If you would like some drafting help making a more formal
> drawing of this device, I can volunteer a bit of time. But we should
> do this off list, too, since it may take a bit of help from you,
> before I get everything the way you want it.
> __________________________________________________________
>
> 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: OT: an alternative use for a geophone
From: ChrisAtUpw@.......
Date: Wed, 26 Jul 2006 21:47:36 EDT
In a message dated 2006/07/26, jpopelish@........ writes:
> And Chris, If you would like some drafting help making a more formal
> drawing of this device, I can volunteer a bit of time. But we should
> do this off list, too, since it may take a bit of help from you,
> before I get everything the way you want it.
Thanks, I will try and get a part suppliers list out tomorrow and
maybe some acutal drawings, rather than a freehand sketch. The devices seem to
work quite well and mine goes down to ~4 sec - further than you can get with an
uncompensated geophone.
For anyone who wants to extend the LF range of their geophones by x10,
a circuit by P M Roberts is available. See
http://www.seismicnet.com/bibliography.html
Regards,
Chris Chapman
In a me=
ssage dated 2006/07/26, jpopelish@........ writes:
And Chris, If you would like so=
me drafting help making a more formal
drawing of this device, I can volunteer a bit of time. But we should <=
BR>
do this off list, too, since it may take a bit of help from you,
before I get everything the way you want it.
Thanks, I will try and get a part suppl=
iers list out tomorrow and maybe some acutal drawings, rather than a=20=
freehand sketch. The devices seem to work quite well and mine goes down to ~=
4 sec - further than you can get with an uncompensated geophone.
For anyone who wants to extend the LF r=
ange of their geophones by x10, a circuit by P M Roberts is available. See h=
ttp://www.seismicnet.com/bibliography.html
Regards,
Chris Chapman
Subject: Re: OT: an alternative use for a geophone
From: ChrisAtUpw@.......
Date: Thu, 27 Jul 2006 08:14:46 EDT
In a message dated 2006/07/26 23:21:10 GMT Daylight Time, jpopelish@........
writes:
> And Chris, If you would like some drafting help making a more formal
> drawing of this device, I can volunteer a bit of time. But we should
> do this off list, too, since it may take a bit of help from you,
> before I get everything the way you want it.
Hi There,
Where do you buy brass screws, please? I am looking for 6 / 8 / 32 by
3/8"
Our electronic suppliers keep suitable screws. Yours don't appear to!
Regards,
Chris Chapman
In a me=
ssage dated 2006/07/26 23:21:10 GMT Daylight Time, jpopelish@........ writes=
:
And Chris, If you would like so=
me drafting help making a more formal
drawing of this device, I can volunteer a bit of time. But we should <=
BR>
do this off list, too, since it may take a bit of help from you,
before I get everything the way you want it.
Hi There,
Where do you buy brass screws, please?=20=
I am looking for 6 / 8 / 32 by 3/8"
Our electronic suppliers keep suitable=20=
screws. Yours don't appear to!
Regards,
Chris Chapman
Subject: ebay auction
From: Bob Barns royb1@...........
Date: Thu, 27 Jul 2006 09:54:40 -0400
Hi gang,
Two Nomis Minigraph 7000 Seismographs
Item number: 320011054093
ends Aug 2
Bob
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: OT: an alternative use for a geophone
From: John Popelish jpopelish@........
Date: Thu, 27 Jul 2006 11:21:03 -0400
ChrisAtUpw@....... wrote:
> Where do you buy brass screws, please? I am looking for
> 6 / 8 / 32 by 3/8"
> Our electronic suppliers keep suitable screws. Yours don't appear to!
I buy them at a local Lowes building supply. They have a specialty
hardware section with lots of weird stuff (like brass thumb nuts that
you see on dry cells) in big drawers, though they are a bit pricey.
They also have a rack with small plastic bags of brass screws in
several sizes.
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: OT: an alternative use for a geophone
From: Richard Gagnon richg_1998@.........
Date: Thu, 27 Jul 2006 09:25:18 -0700 (PDT)
--- John Popelish wrote:
> ChrisAtUpw@....... wrote:
>
> > Where do you buy brass screws, please? I am looking for
> > 6 / 8 / 32 by 3/8"
> > Our electronic suppliers keep suitable screws. Yours don't appear to!
>
> I buy them at a local Lowes building supply. They have a specialty
> hardware section with lots of weird stuff (like brass thumb nuts that
> you see on dry cells) in big drawers, though they are a bit pricey.
> They also have a rack with small plastic bags of brass screws in
> several sizes.
>
----------------------------------------------------------------------------
I find mine at Home Depot (14 miles away). Good selection though I try to use a
local hardware store in the town (two miles away) I live in.
Richard Gagnon
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: OT: an alternative use for a geophone
From: ChrisAtUpw@.......
Date: Thu, 27 Jul 2006 18:01:01 EDT
In a message dated 2006/07/26, gmvoeth@........... writes:
> has the tenacity to find the necessary raw materials
Hi there,
See http://www.jclahr.com/science/psn/chapman/piezo/PiezoSensAmp.jpg
Not too difficult, more a question of knowing what to look for and=20
where to find it.
Materials
Double sided 1/16" thick glass circuit board 2" wide x 3.5" long - most=20
Electronic's suppliers
Spacers 30 mm long x 3 mm tapped Farnell No 473-6047 Squires No 600-950
threaded standoff 1818K-ND 1.25" + 6-32 bolts + a couple of washers from=20
http://dkc3.digikey.com/PDF/T053/1454-1457.pdf=20
Bolts Brass 10 mm long x 3 mm dia Pan head // 6-32 x 3/8" US Home Depot /=20
Lowes
Brass 10 mm long x 4 mm dia Pan head // 8-32 x 3/8" US Home Depot /=
=20
Lowes
Brass foil 5 thou from K&S=20
Brass 1/4" x 1/8" rectangular tube x 1.7" from K&S=20
Brass bar 1/2" OD x 1.85" =3D 4.7 cm for 50 gm
Adhesive Holdtite ST3295 two part acrylic adhesive Squires There are several=
=20
suppliers of similar products in the USA
Piezo disk 44 mm OD central sensor 25 mm OD Capacity 40 nF min typical 65 nF
Farnell No 500-3301 No 9843744,=20
Digikey 1N3595 diodes and PZT disks p1421 for piezo elements - 102-1170-ND=20
44mm OD, 70 nF at $1.62=20
www.mouser.com 1N3595 diodes and PZT disks p1270 for piezo elements=20
665-KBI-4406 44mm OD, 70nF at $1.69 665-APS-100 50mm OD, 65nF at $2.05=20
Maplin YU83E 41 mm =A30.49
Damping
Magnet NdFeB 10 mm OD x 5mm high Maplin YA29G KJ Magnetics and many others=
=20
=20
Copper bar 5/8" OD
Alternative Damping
As an alternative to magnetic damping you can mount a brass L flange on top=20
of the V top suspension and attach either Sorbothane sheet or polyurethane f=
oam=20
to it and to both side glass boards.
Sorbothane from EdSci No. 3037000 Very good
Polyurethane Foam lightest grade - needs replacing annually - keep away from=
=20
light / sunshine
You will need to drill and tap the brass mass / rod. This can be done=
=20
with a press drill, but it is much easier in a lathe.. To square off the end=
s=20
of the rod, file roughly square, then mount the rod in the chuck and press=20
lightly onto a flat file on the baseplate and then onto emery paper. Mark an=
d=20
centre the end holes, clamp the rod vertically in a vice, drill and tap to s=
uit=20
the bolts. You may also need to 'true up' the head of the lower screw befor=
e=20
you solder it.
To buy the brass and copper bars, you may need to find a non ferrous=20
metals stockist or a hobby shop which deals in metals. I have a local metals=
=20
supermarket and periodically visit it to find 'offcuts'.
Digikey USA and UK www.digikey.com=20
Edmund Scientific USA http://www.edsci.com/=20
Farnell UK & USA http://www.farnell.com/
Holdtite UK http://www.holdtite.com/
KJ Magnetics USA http://www.kjmagnetics.com
K&S Metals Hobby suppliers USA & UK www.ksmetals.com
Maplin UK www.maplin.co.uk
Mouser USA www.mouser.com
Squires UK www.squirestools.com
Regards,
Chris Chapman
In a message dated 2006/07/26, gmvo=
eth@........... writes:
has the tenacity to find the ne=
cessary raw materials
Hi there,
See http://www.jclahr.com/science/psn/c=
hapman/piezo/PiezoSensAmp.jpg
Not too difficult, more a question of k=
nowing what to look for and where to find it.
Materials
Double sided 1/16" thick glass circuit board 2" wide x 3.5" long - mo=
st Electronic's suppliers
Spacers 30 mm long x 3 mm tapped Farnell No 473-6047 Squires No 600-950
threaded standoff 1818K-ND 1.25" + 6-32 bolts + a couple of washers f=
rom http://dkc3.digikey.com/PDF/T053/1454-1457.pdf
Bolts Brass 10 mm long x 3 mm dia Pan head // 6-32 x 3/8" US Home Depot / Lo=
wes
Brass 10 mm long x 4 mm dia=
Pan head // 8-32 x 3/8" US Home Depot / Lowes
Brass foil 5 thou from K&S
Brass 1/4" x 1/8" rectangular tube x 1.7" from K&S
Brass bar 1/2" OD x 1.85" =3D 4.7 cm for 50 gm
Adhesive Holdtite ST3295 two part acrylic adhesive Squires There are=20=
several suppliers of similar products in the USA
Piezo disk 44 mm OD central sensor 25 mm OD Capacity 40 nF min typical 65 nF=
Farnell No 500-3301 No 9843744,
Digikey 1N3595 diodes and PZT disks p1421 for piezo elements - 1=
02-1170-ND 44mm OD, 70 nF at $1.62
www.mouser.com 1N3595 diodes and PZT disks p1270 for piezo elements 665-KBI-=
4406 44mm OD, 70nF at $1.69 665-APS-100 50mm OD, 65nF at $2.05
Maplin YU83E 41 mm =A30.49
Damping
Magnet NdFeB 10 mm OD x 5mm high Maplin YA29G KJ Magnetics and m=
any others =
&nbs=
p; &n=
bsp;
Copper bar 5/8" OD
Alternative Damping
As an alternative to magnetic damping you can mount a brass L flange on top=20=
of the V top suspension and attach either Sorbothane sheet or polyurethane f=
oam to it and to both side glass boards.
Sorbothane from EdSci No. 3037000 Very good
Polyurethane Foam lightest grade - needs replacing annually - keep away from=
light / sunshine
You will need to drill and tap the bras=
s mass / rod. This can be done with a press drill, but it is much easier in=20=
a lathe.. To square off the ends of the rod, file roughly square, then mount=
the rod in the chuck and press lightly onto a flat file on the baseplate an=
d then onto emery paper. Mark and centre the end holes, clamp the rod vertic=
ally in a vice, drill and tap to suit the bolts. You may also need to=20=
'true up' the head of the lower screw before you solder it.
To buy the brass and copper bars, you m=
ay need to find a non ferrous metals stockist or a hobby shop which deals in=
metals. I have a local metals supermarket and periodically visit it to find=
'offcuts'.
Digikey USA and UK www.digikey.com
Edmund Scientific USA http://www.edsci.com/
Farnell UK & USA http://www.farnell.com/
Holdtite UK http://www.holdtite.com/
KJ Magnetics USA http://www.kjmagnetics.com
K&S Metals Hobby suppliers USA & UK www.ksmetals.com
Maplin UK www.maplin.co.uk
Mouser USA www.mouser.com
Squires UK www.squirestools.com
Regards,
Chris Chapman
Subject: Reykjanes Ridge earthquakes today
From: =?ISO-8859-1?Q?J=F3n_Fr=EDmann?= jonfr500@.........
Date: Sat, 29 Jul 2006 01:21:53 +0000
Hi all
Today there where three earthquakes out to the Reykjanes Ridge, this is
not the first time I have recored earthquakes from that area. But I did
record two earthquakes from that area in Febuary this year. But then I
didn't see the p and s wave as I did today. The only thing I have
changed in the meantime is the cable and I have ground connected the
cable. It surprices me that it did make such huge diffrent as it
apperently did.
Regards.
--
Jón Frímann
http://www.jonfr.com
http://www.simnet.is/jonfr500/earthquake/
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Paper on Seismometer design based on a simple theory of instrument-generated
From: Larry Cochrane lcochrane@..............
Date: Mon, 31 Jul 2006 21:25:21 -0700
Hi Everyone,
From Dr. Randall Peters...
>I've just posted to my webpage a new article, titled "Seismometer design based on a
>simple theory of instrument-generated noise equivalent power", online at
>http://physics.mercer.edu/hpage/inep/inep.html
>Larry, this paper might be interesting to the PSN list-serve members if you
>want to draw their attention to it. It documents why the Volksmeter (and for
>that matter the Shackleford-Gunderson pendulum) perform better than the majority
>of folks ever thought possible.
Regards,
Larry Cochrane
Redwood City, PSN
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Paper on Seismometer design based on a simple theory of instrument-generated noise equivalent power
From: "meredith lamb" paleoartifact@.........
Date: Mon, 31 Jul 2006 23:31:15 -0600
Hi all,
Theres a article on Randall Peters "Volksmeter" seismometer at:
http://www.eetimes.com/showArticle.jhtml?articleID=175801455
It does go into some details of the instrument. Its essentially
a "hanging pendulum" with very low pivot friction and much higher
inherent stability and alot less tilt adjustment/s than "~probably all"
older design horizontal sensing seismometers.
Meredith Lamb
On 7/31/06, Larry Cochrane wrote:
>
> Hi Everyone,
>
> From Dr. Randall Peters...
>
> >I've just posted to my webpage a new article, titled "Seismometer design
> based on a
> >simple theory of instrument-generated noise equivalent power", online at
>
> >http://physics.mercer.edu/hpage/inep/inep.html
>
> >Larry, this paper might be interesting to the PSN list-serve members if
> you
> >want to draw their attention to it. It documents why the Volksmeter (and
> for
> >that matter the Shackleford-Gunderson pendulum) perform better than the
> majority
> >of folks ever thought possible.
>
> Regards,
> Larry Cochrane
> Redwood City, PSN
>
>
Hi all,
Theres a article on Randall Peters "Volksmeter" seismometer at:
It does go into some details of the instrument. Its essentially
a "hanging pendulum" with very low pivot friction and much higher
inherent stability and alot less tilt adjustment/s than "~probably all"
older design horizontal sensing seismometers.
Meredith Lamb
On 7/31/06, Larry Cochrane <lcochrane@..............> wrote:
Hi Everyone,
From Dr. Randall Peters...
>I've just posted to my webpage a new article, titled "Seismometer design based on a
>simple theory of instrument-generated noise equivalent power", online at
>http://physics.mercer.edu/hpage/inep/inep.html
>Larry, this paper might be interesting to the PSN list-serve members if you
>want to draw their attention to it. It documents why the Volksmeter (and for
>that matter the Shackleford-Gunderson pendulum) perform better than the majority
>of folks ever thought possible.
Regards,
Larry Cochrane
Redwood City, PSN
Subject: Re: Check you VHS video tapes...for crossed rod pivot parts
From: "meredith lamb" paleoartifact@.........
Date: Tue, 1 Aug 2006 00:06:38 -0600
Hi all,
The report on using VHS tape cassette spacers is unfortunately
bad. I find there is too much variations of the exterior/interior sizes of
the
VHS tape guides/spacers, and; of the diameter variations along the lengths
of the hardware store mounting bolts to "easily" consider using such for
crossed rod pivots. The crossed rod on such tend to "walk" over time
and oscillations, away from their initial positions due to differences of
level height, diameters and possibly minor weight shift movement of the
spacers themselves on the bolts.
Nevertheless I did setup acouple variations of such, and they oscillated
from 5 to 6.5 hours; from their initial offset....which is a reflection of
the
smooth surfaces (pivot) low friction.
Meredith Lamb
On 7/5/06, meredith lamb wrote:
>
> Hi all,
>
> Heyyyyy...this part seemingly has real potential ! If you even vaguely
> have followed last
> years emails on crossed rod pivot/hinges; this might be something you can
> also try
> during any bored or curious moments.
>
> Its within common VHS video tape cassettes. Most all cassettes use two
> tape spacer/
> guides, that appear to be ultra smooth stainless steel. The minority can
> be plastic.
> Most of them appear to be punched/stamped out of sheet metal and then
> formed
> into a round tube; and then they appear to have been further smoothed to
> where they
> don't damage the video tape moving over their surfaces. The rarest
> spacer/guide is a
> complete cut off tube. You can open the release latch on the side of the
> cassette to
> view parts of these tubes behind the tape. You can generally easily open
> to remove
> them by first removing 5 small phillips head screws on the bottom of the
> cassette
> itself. The rare cassette might be plastic welded shut.
>
> The main point here being the very smooth surface of these metal tubes is
> what one
> absolutely needs for a crossed rod pivot. Naturally, the contact points
> won't be over
> the lengthwise joint. Being as they are essentially tubes, one can use
> bolts and
> nuts to seat/mount them, which is also very convenient. If you only use
> these, you
> only need 4 (2 cassettes) tubes; 2 for running in one spaced apart
> direction, and 2
> "cross rod" (right angle to the other two) to attach to either side of the
> boom you
> use. They appear to all be ~ .630" length (16.0mm), .225" outside
> diameter (5.75mm),
> .190" inside diameter (4.90mm), with a wall thickness of .0175" (.5mm).
>
> The second main point here, is that from testing a variety of solid rod
> kind of
> material late last year; their low friction level is absolutely amazing.
> This means
> greater seismic sensitivity especially for the low level mass enertia
> offsets we
> either can or can't sensor pickup with a majority of "home brew"
> seismometers.
>
> Credit Chris Chapman for bringing up the "crossed rod pivot" subject late
> last year!
>
> I intend to try such first as another "test table top edge" setup
> eventually; where
> there is only the pivot arrangement, and a test boom and mass. This would
> be a
> gravity vertical hanging mass pendulum. Its not really a S-G per-say; as
> S-G's use
> flexible strips of metal (torque limiting) as the
> pivots...which...essentially....make
> them kind of partial accelerometers. This would be a horizontal
> directional sensing
> unit. Will get back with you all later....with the specific test model
> results; whether
> its good, bad, or somewhere inbetween, as compared to solid rods tests of
> the past.
>
> Meredith Lamb
>
>
>
Hi all,
The report on using VHS tape cassette spacers is unfortunately
bad. I find there is too much variations of the exterior/interior sizes of the
VHS tape guides/spacers, and; of the diameter variations along the lengths
of the hardware store mounting bolts to "easily" consider using such for
crossed rod pivots. The crossed rod on such tend to "walk" over time
and oscillations, away from their initial positions due to differences of
level height, diameters and possibly minor weight shift movement of the
spacers themselves on the bolts.
Nevertheless I did setup acouple variations of such, and they oscillated
from 5 to 6.5 hours; from their initial offset....which is a reflection of the
smooth surfaces (pivot) low friction.
Meredith Lamb
On 7/5/06, meredith lamb <paleoartifact@.........
> wrote:
Hi all,
Heyyyyy...this part seemingly has real potential ! If you even vaguely have followed last
years emails on crossed rod pivot/hinges; this might be something you can also try
during any bored or curious moments.
Its within common VHS video tape cassettes. Most all cassettes use two tape spacer/
guides, that appear to be ultra smooth stainless steel. The minority can be plastic.
Most of them appear to be punched/stamped out of sheet metal and then formed
into a round tube; and then they appear to have been further smoothed to where they
don't damage the video tape moving over their surfaces. The rarest spacer/guide is a
complete cut off tube. You can open the release latch on the side of the cassette to
view parts of these tubes behind the tape. You can generally easily open to remove
them by first removing 5 small phillips head screws on the bottom of the cassette
itself. The rare cassette might be plastic welded shut.
The main point here being the very smooth surface of these metal tubes is what one
absolutely needs for a crossed rod pivot. Naturally, the contact points won't be over
the lengthwise joint. Being as they are essentially tubes, one can use bolts and
nuts to seat/mount them, which is also very convenient. If you only use these, you
only need 4 (2 cassettes) tubes; 2 for running in one spaced apart direction, and 2
"cross rod" (right angle to the other two) to attach to either side of the boom you
use. They appear to all be ~ .630" length (16.0mm), .225" outside diameter (5.75mm),
.190" inside diameter (4.90mm), with a wall thickness of .0175" (.5mm).
The second main point here, is that from testing a variety of solid rod kind of
material late last year; their low friction level is absolutely amazing. This means
greater seismic sensitivity especially for the low level mass enertia offsets we
either can or can't sensor pickup with a majority of "home brew" seismometers.
Credit Chris Chapman for bringing up the "crossed rod pivot" subject late last year!
I intend to try such first as another "test table top edge" setup eventually; where
there is only the pivot arrangement, and a test boom and mass. This would be a
gravity vertical hanging mass pendulum. Its not really a S-G per-say; as S-G's use
flexible strips of metal (torque limiting) as the pivots...which...essentially....make
them kind of partial accelerometers. This would be a horizontal directional sensing
unit. Will get back with you all later....with the specific test model results; whether
its good, bad, or somewhere inbetween, as compared to solid rods tests of the past.
Subject: Event files
From: Robert Laney faultshake@.........
Date: Tue, 1 Aug 2006 19:40:02 -0700 (PDT)
When trying to access event file data on the NEIC-All events ftp I get only events from June 16 to June 30, 2006. Is the site down? Is anyone else having this problem?
Thanks.
Bob Laney
---------------------------------
How low will we go? Check out Yahoo! Messengers low PC-to-Phone call rates.
When trying to access event file data on the NEIC-All events ftp I get only events from June 16 to June 30, 2006. Is the site down? Is anyone else having this problem?
Thanks.
Bob Laney
How low will we go? Check out Yahoo! Messengers low PC-to-Phone call rates.
Subject: Re: Event files
From: John or Jan Lahr JohnJan@........
Date: Tue, 01 Aug 2006 21:34:39 -0700
On Monday, I got this message from the USGS NEIC:
We had to take one of our computers off-line last week.
As a result we are not able to update the
ftp area. We are working on getting this link back, but right
now I don't know if this will only take another day or two, or longer.
I am sorry about the inconvenience
John
At 07:40 PM 8/1/2006, you wrote:
>When trying to access event file data on the NEIC-All events ftp I
>get only events from June 16 to June 30, 2006. Is the site
>down? Is anyone else having this problem?
>
>Thanks.
>
>Bob Laney
>
>
>How low will we go? Check out Yahoo! Messenger's low PC-to-Phone call rates.
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Event files
From: Robert Laney faultshake@.........
Date: Wed, 2 Aug 2006 19:02:02 -0700 (PDT)
Thanks John for the information.
Bob
John or Jan Lahr wrote:
On Monday, I got this message from the USGS NEIC:
We had to take one of our computers off-line last week.
As a result we are not able to update the
ftp area. We are working on getting this link back, but right
now I don't know if this will only take another day or two, or longer.
I am sorry about the inconvenience
John
At 07:40 PM 8/1/2006, you wrote:
>When trying to access event file data on the NEIC-All events ftp I
>get only events from June 16 to June 30, 2006. Is the site
>down? Is anyone else having this problem?
>
>Thanks.
>
>Bob Laney
>
>
>How low will we go? Check out Yahoo! Messenger's low PC-to-Phone call rates.
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
---------------------------------
How low will we go? Check out Yahoo! Messengers low PC-to-Phone call rates.
Thanks John for the information.
Bob
John or Jan Lahr <JohnJan@........> wrote:
On Monday, I got this message from the USGS NEIC:
We had to take one of our computers off-line last week.
As a result we are not able to update the
ftp area. We are working on getting this link back, but right
now I don't know if this will only take another day or two, or longer.
I am sorry about the inconvenience
John
At 07:40 PM 8/1/2006, you wrote:
>When trying to access event file data on the NEIC-All events ftp I
>get only events from June 16 to June 30, 2006. Is the site
>down? Is anyone else having this problem?
>
>Thanks.
>
>Bob Laney
>
>
>How low will we go? Check out Yahoo! Messenger's low PC-to-Phone call
rates.
__________________________________________________________
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.
How low will we go? Check out Yahoo! Messengers low PC-to-Phone call rates.
Subject: Lehman Sensor Parts for Sale
From: jr_brady@...........
Date: Fri, 04 Aug 2006 18:59:47 +0000
All,
I'm offering the following parts for sale to the group. They were used in
the construction of a Lehman sensor. Offers for some or all are accepted.
An image file is available if you want to view before making an offer.
Please contact me if you are interested. I can only ship to U.S. locations,
sorry.
Thank you,
Jason Brady Lynnwood, WA USA
jr_brady (at) comcast (dot) net
(1) PSN-ADC-EQAMP Four-channel Seismic Amplifier/Filter Board
(1) PSN-ADC-SERIAL 16-Bit Serial Output Analog to Digital Converter Board
Note: Boards mounted together in aluminum enclosure. Slightly used, fully
operational, excellent condition.
(1) Full spool of 36 ga magnet wire
(2) Partial spools of 34 ga magnet wire
(2) Hand-made coils (using 34 ga wire from partial spools)
(3) Alnico horse shoe magnets
(2) 7-1/2" Turnbuckles
(2) Line levels
(1) Guitar string, steel
(5) 4" x 4" copper sheets, varying thicknesses
(1) 3" x 6" copper sheet, 1/4" thick
(1) Pkg of 10 brass ball bearing, 1/4", grade 200
(1) Pkg of 50 brass machine screw, pan head, 10-32 thread, 1-1/2" length
(1) Pkg of 100 brass flat washer, 10-S
(1) Pkg of 100 brass hex machine nut, 10-32 thread
(1) Pkg of 50 brass hex machine nut, 3/18-16 thread
(1) Pkg of 50 brass flat washer, 24-S
(1) Pkg of 100 brass hex machine screw, pan head, 8-32 thread, 1-1/2" length
(1) Pkg of 100 brass hex machine screw, pan head, 8-32 thread, 1" length
(1) Pkg of 100 brass hex machine screw, pan head, 8-32 thread, 3/4" length
(1) Pkg of 100 brass hex machine nut, 8-32 thread
(1) Pkg of 100 brass flat washer, 8-S
Note: Brass part quantities may be slightly less than stated.
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Lehman Sensor Parts for Sale
From: ChrisAtUpw@.......
Date: Sat, 5 Aug 2006 05:08:16 EDT
In a message dated 04/08/06, jr_brady@........... writes:
> I'm offering the following parts for sale to the group. They were used in
> the construction of a Lehman sensor.
> Thank you,
> Jason Brady Lynnwood, WA USA
> jr_brady (at) comcast (dot) net
Hi Jason,
If you would specify the sizes / quantities outlined below as queries,
it would be a great help, please. Otherwise we don't know what you are trying
to sell!
There are maybe a dozen sizes of 'Alnico Horseshoe Magnets' - there
should be a type number on the original order, if not on the magnet.
What were you using brass ball bearings for? Stainless steel is
usually used.
Regards,
Chris Chapman
>
> (1) PSN-ADC-EQAMP Four-channel Seismic Amplifier/Filter Board
How many amplifiers are there on the board?
> (1) PSN-ADC-SERIAL 16-Bit Serial Output Analog to Digital Converter Board
> Note: Boards mounted together in aluminum enclosure. Slightly used, fully
> operational, excellent condition.
Does it have a cable for connecting it to a computer?
> (1) Full spool of 36 ga magnet wire
What weight on the spool? They come in many sizes.
> (2) Partial spools of 34 ga magnet wire
What weight?
> (2) Hand-made coils (using 34 ga wire from partial spools)
> (3) Alnico horse shoe magnets
How many and what sizes?
> (2) 7-1/2" Turnbuckles
How many?
> (2) Line levels
How many?
> (1) Guitar string, steel
What wire diameter / music application?
> (5) 4" x 4" copper sheets, varying thicknesses
How many and what thicknesses?
> (1) 3" x 6" copper sheet, 1/4" thick
> (1) Pkg of 10 brass ball bearing, 1/4", grade 200
> (1) Pkg of 50 brass machine screw, pan head, 10-32 thread, 1-1/2" length
> (1) Pkg of 100 brass flat washer, 10-S
> (1) Pkg of 100 brass hex machine nut, 10-32 thread
> (1) Pkg of 50 brass hex machine nut, 3/18-16 thread
> (1) Pkg of 50 brass flat washer, 24-S
> (1) Pkg of 100 brass hex machine screw, pan head, 8-32 thread, 1-1/2" length
> (1) Pkg of 100 brass hex machine screw, pan head, 8-32 thread, 1" length
> (1) Pkg of 100 brass hex machine screw, pan head, 8-32 thread, 3/4" length
> (1) Pkg of 100 brass hex machine nut, 8-32 thread
> (1) Pkg of 100 brass flat washer, 8-S
In a me=
ssage dated 04/08/06, jr_brady@........... writes:
I'm offering the following part=
s for sale to the group. They were used in
the construction of a Lehman sensor.
Thank you,
Jason Brady Lynnwood, WA USA
jr_brady (at) comcast (dot) net
Hi Jason,
If you would specify the sizes / quanti=
ties outlined below as queries, it would be a great help, please. Otherwise=20=
we don't know what you are trying to sell!
There are maybe a dozen sizes of 'Alnic=
o Horseshoe Magnets' - there should be a type number on the original order,=20=
if not on the magnet.
What were you using brass ball bearings=
for? Stainless steel is usually used.
Regards,
Chris Chapman
(1) PSN-ADC-EQAMP Four-channel Seismic Amplifier/Filter Board
How many amplifiers are there on the b=
oard?
(1) PSN-ADC-SERIAL 16-Bit Seria=
l Output Analog to Digital Converter Board
Note: Boards mounted together in aluminum enclosure. Slightly us=
ed, fully
operational, excellent condition.
Does it have a cable for connecting it=
to a computer?
(1) Full spool of 36 ga magnet=20=
wire
What weight on the spool? They come in=
many sizes.
(2) Partial spools of 34 ga mag=
net wire
What weight?
(2) Hand-made coils (using 34 g=
a wire from partial spools)
(3) Alnico horse shoe magnets
How many and what sizes?
(2) 7-1/2" Turnbuckles
How many?
(2) Line levels
How many?
(1) Guitar string, steel
=
What wire diameter / music application=
?
(5) 4" x 4" copper sheets, vary=
ing thicknesses
How many and what thicknesses?<=
FONT COLOR=3D"#000000" BACK=3D"#ffffff" style=3D"BACKGROUND-COLOR: #ffffff"=
SIZE=3D2 PTSIZE=3D10 FAMILY=3D"SANSSERIF" FACE=3D"Arial" LANG=3D"0">
(1) 3" x 6" copper sheet, 1/4"=20=
thick
(1) Pkg of 10 brass ball bearing, 1/4", grade 200
(1) Pkg of 50 brass machine screw, pan head, 10-32 thread, 1-1/2" length
(1) Pkg of 100 brass flat washer, 10-S
(1) Pkg of 100 brass hex machine nut, 10-32 thread
(1) Pkg of 50 brass hex machine nut, 3/18-16 thread
(1) Pkg of 50 brass flat washer, 24-S
(1) Pkg of 100 brass hex machine screw, pan head, 8-32 thread, 1-1/2" length=
(1) Pkg of 100 brass hex machine screw, pan head, 8-32 thread, 1" length
(1) Pkg of 100 brass hex machine screw, pan head, 8-32 thread, 3/4" length
(1) Pkg of 100 brass hex machine nut, 8-32 thread
(1) Pkg of 100 brass flat washer, 8-S
Subject: Re: SG Seismometer
From: ChrisAtUpw@.......
Date: Sat, 5 Aug 2006 06:40:06 EDT
Hi Larry,
I note that you are no longer supplying the completed electronics'
board and parts for the SG seismometer. I presume that this is a commercial
decision. However, it seems to have been put into effect without any prior
notification to members of psn.
However, would you supply a FULL PARTS & SUPPLIER LIST and ALSO either
STOCK THE BOARDS, or arrange for a named supplier to market the latest
design, please? This should be inexpensive for you and will provide an adequate
service to potential constructors.
A SG pendulum system is a lot easier to construct mechanically for a
beginner than a Lehman. However, if NEITHER the complete electronics' board NOR
the PCB are available, making one can only be recommended to experienced /
skilled constructors with a reasonable chance of success.
Please, could you give this service to potential experimenters your
serious consideration? I note that Prof. Randall Peters mentioned the SG
construction in his recent letter!
Regards,
Chris Chapman
Hi Larr=
y,
I note that you are no longer supplying=
the completed electronics' board and parts for the SG seismometer. I presum=
e that this is a commercial decision. However, it seems to have been put int=
o effect without any prior notification to members of psn.
However, would you supply a FULL PARTS=20=
& SUPPLIER LIST and ALSO either STOCK THE BOARDS, or arrange for a named=
supplier to market the latest design, please? This should be inexpensive fo=
r you and will provide an adequate service to potential constructors.
A SG pendulum system is a lot easier to=
construct mechanically for a beginner than a Lehman. However, if NEITHER th=
e complete electronics' board NOR the PCB are available, making one can only=
be recommended to experienced / skilled constructors with a reasonable chan=
ce of success.
Please, could you give this service to=20=
potential experimenters your serious consideration? I note that Prof. Randal=
l Peters mentioned the SG construction in his recent letter!
Regards,
Chris Chapman
Subject: ebay auction
From: Bob Barns royb1@...........
Date: Sun, 06 Aug 2006 09:55:00 -0400
Hi gang,
Geokon 8001 DataLogger 4500cx-100 Seismometer 760' wire
Measure Record Seismic earthquake sensor transducer Item number:
220014286393
ends Aug 12
--------------
Teledyne Geo. Strong-Motion Seismograph Accelerograph
Item number: 120017222790
ends Aug 12
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Lehman Sensor Parts for Sale
From: jr_brady@...........
Date: Mon, 07 Aug 2006 00:20:38 +0000
All,
Please see answers to Chris' questions below.
Thank you.
-------------- Original message ----------------------
From: ChrisAtUpw@.......
> In a message dated 04/08/06, jr_brady@........... writes:
>
> > I'm offering the following parts for sale to the group. They were used in
> > the construction of a Lehman sensor.
> > Thank you,
> > Jason Brady Lynnwood, WA USA
> > jr_brady (at) comcast (dot) net
>
> Hi Jason,
>
> If you would specify the sizes / quantities outlined below as queries,
> it would be a great help, please. Otherwise we don't know what you are trying
> to sell!
Sorry, I thought it was clear that "(n)" specifies quantity of an item. I don't understand what you mean by "queries."
>
> There are maybe a dozen sizes of 'Alnico Horseshoe Magnets' - there
> should be a type number on the original order, if not on the magnet.
I located one receipt - see additional info below. For the other two, measurements are mine because there is no identifying information available.
>
> What were you using brass ball bearings for? Stainless steel is
> usually used.
I attempted to use a threaded brass rod with a matching brass ball bearing as a boom. Unfortunately the brass rod was not stiff enough. Instead, a square aluminimum rod with a steel ball bearing worked fine.
> Regards,
>
> Chris Chapman
>
> >
> > (1) PSN-ADC-EQAMP Four-channel Seismic Amplifier/Filter Board
>
> How many amplifiers are there on the board?
It's the four-channel (fully-loaded) board so there are four amplifier/filters. You can simultaneously attach four seismographs. From the docs:
Lowpass filter cutoff frequency: 5 Hz
Highpass filter cutoff frequency: 60 seconds
Input impedance: 10K
Gain range with gain jumper installed: ~160 to 600
Gain range with gain jumper removed: ~600 to 8000
>
> > (1) PSN-ADC-SERIAL 16-Bit Serial Output Analog to Digital Converter Board
> > Note: Boards mounted together in aluminum enclosure. Slightly used, fully
> > operational, excellent condition.
>
> Does it have a cable for connecting it to a computer?
Yes. Includes the wall-wart power supply, serial cable, docs and sale receipt from Larry Cochrane. I am the original purchaser and owner.
Has WWV Time Correction option, too.
Note: This hardware originally cost $485 in 2004. It has been rarely used. I think a fair price is $300 but will consider other offers, especially if you want the other items as a package.
>
> > (1) Full spool of 36 ga magnet wire
>
> What weight on the spool? They come in many sizes.
One pound.
>
> > (2) Partial spools of 34 ga magnet wire
>
> What weight?
Each was one pound. I'm guessing about 1/5 to 1/4 remain on the spools.
>
> > (2) Hand-made coils (using 34 ga wire from partial spools)
> > (3) Alnico horse shoe magnets
>
> How many and what sizes?
Two hand-made coils using 3" plastic discs attached to a 1" wood core. The second turned out much better than the first and fits nicely between the large horse shoe magnet (it was mounted on the boom with an aluminum L-bracket, still attached). You can reuse the magnet wire from the first coil or fix it, your choice.
Lacking a winder machine, I have no idea what length of wire is on each coil.
Large horse shoe magnet is McMaster-Carr 5841-K14 "Alnico 5 magnet, bridge, 1-1/8" L O'All, 1-3/4" W O'All, 30 lbs pull".
Two identical small horse shoe magnets 7/8" between poles. Imagine magnet is oriented like an upside-down "U". 1-1/8" high, 1-3/4" wide, 1-1/8" deep.
All three have keep bars and are quite strong.
>
> > (2) 7-1/2" Turnbuckles
>
> How many?
Quanitity 2.
>
> > (2) Line levels
>
> How many?
Quantity 2. You find these at any hardware store. One was mounted on the boom and makes leveling it quite convenient.
>
> > (1) Guitar string, steel
>
> What wire diameter / music application?
..017 Plain steel string. I used one of these along with the turnbuckle to hold the boom up.
>
> > (5) 4" x 4" copper sheets, varying thicknesses
>
> How many and what thicknesses?
Quantity five. 8 oz, 16 oz, 24 oz, 32 oz, 48 oz. These were from a "sample pack" from onlinemetals.com.
>
> > (1) 3" x 6" copper sheet, 1/4" thick
> > (1) Pkg of 10 brass ball bearing, 1/4", grade 200
> > (1) Pkg of 50 brass machine screw, pan head, 10-32 thread, 1-1/2" length
> > (1) Pkg of 100 brass flat washer, 10-S
> > (1) Pkg of 100 brass hex machine nut, 10-32 thread
> > (1) Pkg of 50 brass hex machine nut, 3/18-16 thread
> > (1) Pkg of 50 brass flat washer, 24-S
> > (1) Pkg of 100 brass hex machine screw, pan head, 8-32 thread, 1-1/2" length
> > (1) Pkg of 100 brass hex machine screw, pan head, 8-32 thread, 1" length
> > (1) Pkg of 100 brass hex machine screw, pan head, 8-32 thread, 3/4" length
> > (1) Pkg of 100 brass hex machine nut, 8-32 thread
> > (1) Pkg of 100 brass flat washer, 8-S
>
In a me=
ssage dated 04/08/06, jr_brady@........... writes:
I'm offering the following part=
s for sale to the group. They were used in
the construction of a Lehman sensor.
Thank you,
Jason Brady Lynnwood, WA USA
jr_brady (at) comcast (dot) net
Hi Jason,
If you would specify the sizes / quanti=
ties outlined below as queries, it would be a great help, please. Otherwise=20=
we don't know what you are trying to sell!
There are maybe a dozen sizes of 'Alnic=
o Horseshoe Magnets' - there should be a type number on the original order,=20=
if not on the magnet.
What were you using brass ball bearings=
for? Stainless steel is usually used.
Regards,
Chris Chapman
(1) PSN-ADC-EQAMP Four-channel Seismic Amplifier/Filter Board
How many amplifiers are there on the b=
oard?
(1) PSN-ADC-SERIAL 16-Bit Seria=
l Output Analog to Digital Converter Board
Note: Boards mounted together in aluminum enclosure. Slightly us=
ed, fully
operational, excellent condition.
Does it have a cable for connecting it=
to a computer?
(1) Full spool of 36 ga magnet=20=
wire
What weight on the spool? They come in=
many sizes.
(2) Partial spools of 34 ga mag=
net wire
What weight?
(2) Hand-made coils (using 34 g=
a wire from partial spools)
(3) Alnico horse shoe magnets
How many and what sizes?
(2) 7-1/2" Turnbuckles
How many?
(2) Line levels
How many?
(1) Guitar string, steel
=
What wire diameter / music application=
?
(5) 4" x 4" copper sheets, vary=
ing thicknesses
How many and what thicknesses?<=
FONT COLOR=3D"#000000" BACK=3D"#ffffff" style=3D"BACKGROUND-COLOR: #ffffff"=
SIZE=3D2 PTSIZE=3D10 FAMILY=3D"SANSSERIF" FACE=3D"Arial" LANG=3D"0">
(1) 3" x 6" copper sheet, 1/4"=20=
thick
(1) Pkg of 10 brass ball bearing, 1/4", grade 200
(1) Pkg of 50 brass machine screw, pan head, 10-32 thread, 1-1/2" length
(1) Pkg of 100 brass flat washer, 10-S
(1) Pkg of 100 brass hex machine nut, 10-32 thread
(1) Pkg of 50 brass hex machine nut, 3/18-16 thread
(1) Pkg of 50 brass flat washer, 24-S
(1) Pkg of 100 brass hex machine screw, pan head, 8-32 thread, 1-1/2" length=
(1) Pkg of 100 brass hex machine screw, pan head, 8-32 thread, 1" length
(1) Pkg of 100 brass hex machine screw, pan head, 8-32 thread, 3/4" length
(1) Pkg of 100 brass hex machine nut, 8-32 thread
(1) Pkg of 100 brass flat washer, 8-S
Subject: Meatior fragment found in Norway
From: =?ISO-8859-1?Q?J=F3n_Fr=EDmann?= jonfr500@.........
Date: Wed, 09 Aug 2006 15:32:16 +0000
Hi all
They found a meatior fragment in Norway, it had gone trugh a roof plate
made of steel. See more here.
http://www.aftenposten.no/english/local/article1415787.ece
Regards.
--
Jón Frímann
http://www.jonfr.com
http://www.simnet.is/jonfr500/earthquake/
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Meatior fragment found in Norway
From: "Thomas Dick" dickthomas01@.............
Date: Wed, 9 Aug 2006 12:39:40 -0500
----- Original Message -----
From: "Jón Frímann"
To: "PSN-Postlist"
Sent: Wednesday, August 09, 2006 10:32 AM
Subject: Meatior fragment found in Norway
> Hi all
>
> They found a meatior fragment in Norway, it had gone trugh a roof plate
> made of steel. See more here.
> http://www.aftenposten.no/english/local/article1415787.ece
>
> Regards.
> --
> Jón Frímann
> http://www.jonfr.com
> http://www.simnet.is/jonfr500/earthquake/
>
> __________________________________________________________
>
> 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: Large earthquake in Mexico ?
From: =?ISO-8859-1?Q?J=F3n_Fr=EDmann?= jonfr500@.........
Date: Fri, 11 Aug 2006 14:43:52 +0000
Hi
I am hearing in the news that has been a large earthquake in Mexico, it
is large enugh to sway large sky scrapers. At this moment I haven't seen
anything on event lists (emsc-csem.org or USGS).
Regards.
--
Jón Frímann
http://www.jonfr.com
http://www.simnet.is/jonfr500/earthquake/
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Large earthquake in Mexico ?
From: Canie canie@...........
Date: Fri, 11 Aug 2006 07:52:17 -0700
i can find very recent news reports, but nothing on the maps or lists
yet.
Strong earthquake felt in Mexico City
10 minutes
ago
A strong earthquake was felt in Mexico City on Friday and some buildings
were evacuated, witnesses said.
The tremor was also felt in the neighboring state of Morelos.
The strength of the earthquake was not immediately known or whether there
were any casualties.
Copyright =A9 2006 Reuters Limited
At 07:43 AM 8/11/2006, you wrote:
Hi
I am hearing in the news that has been a large earthquake in Mexico,
it
is large enugh to sway large sky scrapers. At this moment I haven't
seen
anything on event lists (emsc-csem.org or USGS).
Regards.
--
J=F3n Fr=EDmann
http://www.jonfr.com
http://www.simnet.is/jonfr500/earthquake/
Subject: Re: Large earthquake in Mexico ?
From: Canie canie@...........
Date: Fri, 11 Aug 2006 08:03:39 -0700
It finally came thru:
2006/08/11 14:30 M 5.9 MICHOACAN, MEXICO Z=3D 95km 18.62N 100.91W
http://earthquake.usgs.gov/eqcenter/recenteqsww/Quakes/usrgaw.php
Canie
At 07:43 AM 8/11/2006, you wrote:
>Hi
>
>I am hearing in the news that has been a large earthquake in Mexico, it
>is large enugh to sway large sky scrapers. At this moment I haven't seen
>anything on event lists (emsc-csem.org or USGS).
>
>Regards.
>--
>J=F3n Fr=EDmann
>http://www.jonfr.com
>http://www.simnet.is/jonfr500/earthquake/
>
>__________________________________________________________
>
>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: Large earthquake in Mexico ?
From: =?ISO-8859-1?Q?J=F3n_Fr=EDmann?= jonfr500@.........
Date: Fri, 11 Aug 2006 15:10:46 +0000
Hi
emsc-csem marks it as mb6.0 at the moment,
http://www.emsc-csem.org/index.php?page=current&sub=detail&id=ND202;INFO
And the aftershock as mb5.5,
http://www.emsc-csem.org/index.php?page=current&sub=detail&id=ND200;2006
Regards.
--
Jón Frímann
http://www.jonfr.com
http://www.simnet.is/jonfr500/earthquake/
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: RE: Large earthquake in Mexico ?
From: "Kareem from Heyjoojoo.Com" system98765@.............
Date: Fri, 11 Aug 2006 17:51:22 -0700
It was weird how this story finally developed. For some reason, the USGS
maps were very delayed in displaying this event on their maps. Usually, =
by
the time, the news media picks up on the story, it would have already =
been
posted on the USGS website.=20
Wonder why the long delay for such a moderately sized quake.
=20
-----Original Message-----
From: psn-l-request@.............. [mailto:psn-l-request@............... =
On
Behalf Of Canie
Sent: Friday, August 11, 2006 8:04 AM
To: psn-l@..............
Subject: Re: Large earthquake in Mexico ?
It finally came thru:
2006/08/11 14:30 M 5.9 MICHOACAN, MEXICO Z=3D 95km 18.62N 100.91W
http://earthquake.usgs.gov/eqcenter/recenteqsww/Quakes/usrgaw.php
Canie
At 07:43 AM 8/11/2006, you wrote:
>Hi
>
>I am hearing in the news that has been a large earthquake in Mexico, it =
>is large enugh to sway large sky scrapers. At this moment I haven't=20
>seen anything on event lists (emsc-csem.org or USGS).
>
>Regards.
>--
>J=F3n Fr=EDmann
>http://www.jonfr.com
>http://www.simnet.is/jonfr500/earthquake/
>
>__________________________________________________________
>
>Public Seismic Network Mailing List (PSN-L)
>
>To leave this list email PSN-L-REQUEST@.............. with the body of=20
>the message (first line only): unsubscribe See=20
>http://www.seismicnet.com/maillist.html for more information.
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
http://www.seismicnet.com/maillist.html for more information.
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: RE: Large earthquake in Mexico ?
From: =?ISO-8859-1?Q?J=F3n_Fr=EDmann?= jonfr500@.........
Date: Sat, 12 Aug 2006 01:11:55 +0000
Hi
How long does it takes for usgs and other to display earthqukes on there
sites ? Based on the times, I did hear about this earthquake on BBC News
about 10 min, after it did happen.
Regards.
--
Jón Frímann
http://www.jonfr.com
http://www.simnet.is/jonfr500/earthquake/
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Large earthquake in Mexico ?
From: "Geoffrey" gmvoeth@...........
Date: Sat, 12 Aug 2006 03:27:51 -0700
I have noticed that for quite sometime.
I get the distinct impression that the
USGS is operating on a skeleton crew most of the time
they really need to stand watches like the military
does in four hour shifts 24/7/365 but if they did that
all the information would be classified and we
probably would not see the data till after a 24 hour delay.
I think they rely on politics more than science
to report these things in a timely fashion.
It seems they may be afraid of liability related
to real time intelligence.
What you noticed I have noticed for years now.
Shear speculation only because I cant see the big picture.
----- Original Message -----
From: "Kareem from Heyjoojoo.Com"
To:
Sent: Friday, August 11, 2006 5:51 PM
Subject: RE: Large earthquake in Mexico ?
It was weird how this story finally developed. For some reason, the USGS
maps were very delayed in displaying this event on their maps. Usually, by
the time, the news media picks up on the story, it would have already been
posted on the USGS website.
Wonder why the long delay for such a moderately sized quake.
-----Original Message-----
From: psn-l-request@.............. [mailto:psn-l-request@............... On
Behalf Of Canie
Sent: Friday, August 11, 2006 8:04 AM
To: psn-l@..............
Subject: Re: Large earthquake in Mexico ?
It finally came thru:
2006/08/11 14:30 M 5.9 MICHOACAN, MEXICO Z= 95km 18.62N 100.91W
http://earthquake.usgs.gov/eqcenter/recenteqsww/Quakes/usrgaw.php
Canie
At 07:43 AM 8/11/2006, you wrote:
>Hi
>
>I am hearing in the news that has been a large earthquake in Mexico, it
>is large enugh to sway large sky scrapers. At this moment I haven't
>seen anything on event lists (emsc-csem.org or USGS).
>
>Regards.
>--
>Jón Frímann
>http://www.jonfr.com
>http://www.simnet.is/jonfr500/earthquake/
>
>__________________________________________________________
>
>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)
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Large earthquake in Mexico ?
From: "Geoffrey" gmvoeth@...........
Date: Sat, 12 Aug 2006 10:07:31 -0700
***********************************
From: "Geoffrey"
To:
References: <000f01c6bda9$6ecc6710$4001a8c0@heyjoojos63zu7>
Subject: Re: Large earthquake in Mexico ?
I have noticed that for quite sometime.
I get the distinct impression that the
USGS is operating on a skeleton crew most of the time
they really need to stand watches like the military
does in four hour shifts 24/7/365 but if they did that
all the information would be classified and we
probably would not see the data till after a 24 hour delay.
I think they rely on politics more than science
to report these things in a timely fashion.
It seems they may be afraid of liability related
to real time intelligence.
What you noticed I have noticed for years now.
Shear speculation only because I cant see the big picture.
----- Original Message -----
From: "Kareem from Heyjoojoo.Com"
To:
Sent: Friday, August 11, 2006 5:51 PM
Subject: RE: Large earthquake in Mexico ?
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Fwd: 2006-08-11 14:30 (Mw 5.9) MICHOACAN, MEXICO 18.6 -100.9
From: John or Jan Lahr JohnJan@........
Date: Sun, 13 Aug 2006 21:42:24 -0700
Hi Geoffrey,
I got a reviewed location message from the USGS just 18 minutes after the
event in Mexico, which is pretty fast! They now have people on duty 24x7,
which was not done prior to about a year ago. Automatic locations are
not sent to the public, as the computer algorithms are not reliable enough
yet. However, they do go to the tsunami warning groups and others who
need near-real-time information.
Cheers,
John
Geoffrey wrote:
I have noticed that for quite sometime.
I get the distinct impression that the
USGS is operating on a skeleton crew most of the time
they really need to stand watches like the military
does in four hour shifts 24/7/365 but if they did that
all the information would be classified and we
probably would not see the data till after a 24 hour delay.
I think they rely on politics more than science
to report these things in a timely fashion.
It seems they may be afraid of liability related
to real time intelligence.
What you noticed I have noticed for years now.
Shear speculation only because I cant see the big picture.
>Subject: 2006-08-11 14:30 (Mw 5.9) MICHOACAN, MEXICO 18.6 -100.9
>Message-Id: <20060811144817.C89C019E118@....................>
>Date: Fri, 11 Aug 2006 07:48:17 -0700 (PDT)
>
> =3D=3D PRELIMINARY EARTHQUAKE REPORT =3D=3D
>
>Region: MICHOACAN,=20
>MEXICO
>Geographic coordinates: 18.624N, 100.913W
>Magnitude: 5.9 Mw
>Depth: 94 km
>Universal Time (UTC): 11 Aug 2006 14:30:44
>Time near the Epicenter: 11 Aug 2006 09:30:44
>Local time in your area: 11 Aug 2006 07:30:44
>
>Location with respect to nearby cities:
> 6 km (4 miles) NW (325 degrees) of Huetamo, Michoac=E1n, Mexico
> 44 km (27 miles) NW (321 degrees) of Altamirano, Guerrero, Mexico
> 78 km (48 miles) WNW (300 degrees) of Arcelia, Guerrero, Mexico
> 122 km (76 miles) S (170 degrees) of Morelia, Michoac=E1n, Mexico
> 204 km (126 miles) WSW (245 degrees) of MEXICO CITY, D.F., Mexico
>
>
>ADDITIONAL EARTHQUAKE PARAMETERS
>__________________________________________________
>event ID : US rgaw
>version : 7
>number of phases : 185
>rms misfit : 0.79 seconds
>horizontal location error : 4.6 km
>vertical location error : 0.0 km
>maximum azimuthal gap : 93 degrees
>distance to nearest station : 999.9 km
>
>Flinn-Engdahl Region Number =3D 59
>
>This event has been reviewed by a seismologist at NEIC
>For subsequent updates, maps, and technical information, see:
>http://earthquake.usgs.gov/eqcenter/recenteqsww/Quakes/usrgaw.php
>or
>http://earthquake.usgs.gov/
>
>National Earthquake Information Center
>U.S. Geological Survey
>http://neic.usgs.gov
>
>
>________________________________
>
>DISCLAIMER: http://earthquake.usgs.gov/eqcenter/ens/disclaimer.html
>
>This email was sent to jjpub@........
>
>You requested mail for events within 6200.0 miles of Corvallis=
(44.6/-123.3)
>for M5.5 at all times.
>
>
>To change your parameters or unsubscribe, go to:
>http://earthquake.usgs.gov/eqcenter/ens
#################################/ John C. Lahr
################################/ Emeritus Seismologist
###############################/ U.S. Geological Survey
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D/ Central Region Geologic Hazards Team
#############################//#################################
############################//##################################
PO Box 548 =
/###################################
Corvallis, Oregon 97339 /=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
Phone: (541) 758-2699 /####################################
Cell: (541) 740-4844 /#####################################
Fax: (928) 569-0113 /######################################
jjpub@........ /#######################################
http://jclahr.com/science/
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Broken links in psn
From: ChrisAtUpw@.......
Date: Mon, 14 Aug 2006 12:47:40 EDT
Hi there,
The two following references seem to have broken links
Seismic Sensors and Their Calibration. Overview of feedback seismometers
design by Prof. Erhard Wielandt.
Seismometry another article by Prof. Erhard Wielandt.
They can be recovered from
http://www.geophys.uni-stuttgart.de/lehre/skripte/old_skripte/old_skripte.html
Regards,
Chris Chapman
Hi ther=
e,
The two following references seem to ha=
ve broken links
Seismic Sensors and Their Calibration. Overview of feedback seismome=
ters design by Prof. Erhard Wielandt.
Seismometry another article by Prof. Erhard Wielandt.
They can be recovered from http://www.g=
eophys.uni-stuttgart.de/lehre/skripte/old_skripte/old_skripte.html
Regards,
Chris Chapman
Subject: Unkown teleseismic signal
From: =?ISO-8859-1?Q?J=F3n_Fr=EDmann?= jonfr500@.........
Date: Mon, 14 Aug 2006 19:23:00 +0000
Hi all
I am currently monitoring few of Larrys stations, including the usgs
telemetry station. It has come to my attension that there is a
teleseismic signal registered at 18:14 at that station, but I don't see
any earthquake listed, both on usgs website or on the emsc-csem website.
I am wondering if anyone here did pickup this signal or knows about
registration on it.
Regards.
--
Jón Frímann
http://www.jonfr.com
http://www.simnet.is/jonfr500/earthquake/
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Broken links in psn
From: "Jerry Payton" gpayton880@.......
Date: Mon, 14 Aug 2006 15:21:30 -0500
Thank you Chris. That is VERY informative material.
Regards,
Jerry
----- Original Message -----
From: ChrisAtUpw@.......
To: psn-l@..............
Sent: Monday, August 14, 2006 11:47 AM
Subject: Broken links in psn
Hi there,
The two following references seem to have broken links
Seismic Sensors and Their Calibration. Overview of feedback seismometers
design by Prof. Erhard Wielandt.
Seismometry another article by Prof. Erhard Wielandt.
They can be recovered from
http://www.geophys.uni-stuttgart.de/lehre/skripte/old_skripte/old_skripte.html
Regards,
Chris Chapman
Thank you Chris. That is VERY informative material.
Regards,
Jerry
----- Original Message -----
From:=20
ChrisAtUpw@.......
Sent: Monday, August 14, 2006 =
11:47=20
AM
Subject: Broken links in =
psn
Hi=20
there,
The two following=20
references seem to have broken links
Seismic=20
Sensors and Their Calibration. Overview of feedback seismometers =
design by=20
Prof. Erhard Wielandt.
Seismometry=20
another article by Prof. Erhard Wielandt.=20
They can be recovered =
from http://www.geophys.uni-stuttgart.de/lehre/skripte/old_skri=
pte/old_skripte.html
=20
Regards,
Chris =
Chapman=20
Subject: LD701 sensor for Lehman
From: Mike Speed mike8s2@.........
Date: Mon, 14 Aug 2006 15:35:38 -0700 (PDT)
I saw a Lehman which used this as the sensor - what do you guys think (sensitivity, bandwidth, noise floor, etc.):
http://www.omega.com/pptst/LD701.html
---------------------------------
Stay in the know. Pulse on the new Yahoo.com. Check it out.
I saw a Lehman which used this as the sensor - what do you guys think (sensitivity, bandwidth, noise floor, etc.):
http://www.omega.com/pptst/LD701.html
Stay in the know. Pulse on the new Yahoo.com. Check it out.
Subject: RE: LD701 sensor for Lehman
From: "Kareem from Heyjoojoo.Com" system98765@.............
Date: Mon, 14 Aug 2006 18:20:12 -0700
How?
_____
From: psn-l-request@.............. [mailto:psn-l-request@............... On
Behalf Of Mike Speed
Sent: Monday, August 14, 2006 3:36 PM
To: psn-l@..............
Subject: LD701 sensor for Lehman
I saw a Lehman which used this as the sensor - what do you guys think
(sensitivity, bandwidth, noise floor, etc.):
http://www.omega.com/pptst/LD701.html
_____
Stay in the know. Pulse on the new Yahoo.com. Check it
out.
How?
I saw a Lehman which used this as the sensor - what do you =
guys think=20
(sensitivity, bandwidth, noise floor,=20
etc.):
http://www.omega.com/pptst/LD701.html
Stay in the know. Pulse on the new Yahoo.com. Check it=20
out.
Subject: Re: LD701 sensor for Lehman
From: ChrisAtUpw@.......
Date: Mon, 14 Aug 2006 21:44:19 EDT
In a message dated 14/08/06, mike8s2@......... writes:
> I saw a Lehman which used this as the sensor - what do you guys think
> (sensitivity, bandwidth, noise floor, etc.):
>
> http://www.omega.com/pptst/LD701.html
Hi Mike,
You tell us the noise floor, the bandwidth etc and we can maybe give a
realistic answer. The 10 micron repeatability does not sound exciting when
you want to measure at least down to 0.1 micron. At $165, I am not going to buy
one to find out.
I suspect that the bandwidth is likely to be too high allowing extra
noise.
Is there any attractive effect due to energisation of the sensor?
I would like to see some more figures and a direct comparison, please.
The commercial LVDTs that I have used are only OK if you make very low
noise electronics to go with them.
Regards,
Chris Chapman
In a me=
ssage dated 14/08/06, mike8s2@......... writes:
I saw a Lehman which used this=20=
as the sensor - what do you guys think (sensitivity, bandwidth, noise floor,=
etc.):
http://www.omega.com/pptst/LD701.html
Hi Mike,
You tell us the noise floor, the bandwi=
dth etc and we can maybe give a realistic answer. The 10 micron repeatabilit=
y does not sound exciting when you want to measure at least down to 0.1 micr=
on. At $165, I am not going to buy one to find out.
I suspect that the bandwidth is likely=20=
to be too high allowing extra noise.
Is there any attractive effect due to e=
nergisation of the sensor?
I would like to see some more figures a=
nd a direct comparison, please.
The commercial LVDTs that I have used a=
re only OK if you make very low noise electronics to go with them.
Regards,
Chris Chapman
Subject: Fw: USGS
From: "Dale Hardy" photon1@...........
Date: Thu, 17 Aug 2006 10:59:17 +1000
recorded a large event at 1700Z, however USGS site has not updated for a =
few hours?
Dale
recorded a large event at 1700Z, =
however USGS=20
site has not updated for a few hours?
Dale
Subject: Re: Fw: USGS
From: =?ISO-8859-1?Q?J=F3n_Fr=EDmann?= jonfr500@.........
Date: Thu, 17 Aug 2006 01:20:06 +0000
Hi
This event has also not been registerd at emsc-csem far as I can tell,
but that is really strange occrance. I saw the trace of that earthquake
at one of the plots I watch.
Regards.
--
Jón Frímann
http://www.jonfr.com
http://www.simnet.is/jonfr500/earthquake/
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Fw: USGS
From: =?ISO-8859-1?Q?J=F3n_Fr=EDmann?= jonfr500@.........
Date: Thu, 17 Aug 2006 02:08:14 +0000
Hi
This event has also not been registerd at emsc-csem far as I can
tell,
but that is really strange occrance. I saw the trace of that
earthquake
at one of the plots I watch.
Regards.
(re-sent in html format email)
--
Jón Frímann
http://www.jonfr.com
http://www.simnet.is/jonfr500/earthquake/
Hi
This event has also not been registerd at emsc-csem far as I can tell,
but that is really strange occrance. I saw the trace of that earthquake
at one of the plots I watch.
Regards.
(re-sent in html format email)
Subject: Re: Fw: USGS
From: "Dale Hardy" photon1@...........
Date: Thu, 17 Aug 2006 12:47:48 +1000
Jon, my trace is at http://www.daleh.id.au/earthquake.html
thanks
Dale
----- Original Message -----
From: "Jón Frímann"
To:
Sent: Thursday, August 17, 2006 11:20 AM
Subject: Re: Fw: USGS
> Hi
>
> This event has also not been registerd at emsc-csem far as I can tell,
> but that is really strange occrance. I saw the trace of that earthquake
> at one of the plots I watch.
>
> Regards.
> --
> Jón Frímann
> http://www.jonfr.com
> http://www.simnet.is/jonfr500/earthquake/
>
> __________________________________________________________
>
> 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.
>
>
> --
> No virus found in this incoming message.
> Checked by AVG Free Edition.
> Version: 7.1.405 / Virus Database: 268.11.1/421 - Release Date: 16/08/2006
>
>
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: USGS
From: "Geoffrey" gmvoeth@...........
Date: Wed, 16 Aug 2006 19:51:11 -0700
Such A thing does not surprise me.
I have been watching data from the USGS for
maybe 10 years now and I feel if you
are not an insider you will not
receive any realtime reports.
They seem to want to review everything
and analyze it before reporting it.
They seem to fear the liability of being wrong.
If you want real time data you are going
to have to get a Geophysics degree and
work in the field for 20 years then if they
happen to like you, you might get a front row
seat working there analyzing EQs as they come in.
I think they man their center only with
Geophisicist who are nearing the end of their career.
It is a kind of award to have the jobs they hold
in Golden Colorado for years of commendable service.
At least that is how I envision things there
based upon my scant communications with a
Geophysicist named Willis Jacobs.
Willis Jacobs worked very hard and physical for Govmt before
he was working at Golden. He has been retired now for
quite sometime.
He was a Good Man.
Maybe one or more of you have heard of him.
Well...you have now.
Regards;
gmv
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Fw: USGS
From: =?ISO-8859-1?Q?J=F3n_Fr=EDmann?= jonfr500@.........
Date: Thu, 17 Aug 2006 07:55:16 +0000
Hi
Dale Hardy, I monitor two of your plots (trugh the gif image you provide
online) and I did see the earthquake.
However, it doesn't seems to be registered on emsc-csem, the question is
how big was this earthquake and what was the distance.
If it was smaller then mag 4.5 it might explain why the earthquake isn't
registered anywhere.
Regards.
--
Jón Frímann
http://www.jonfr.com
http://www.simnet.is/jonfr500/earthquake/
Hi
Dale Hardy, I monitor two of your plots (trugh the gif image you provide online) and I did see the earthquake.
However, it doesn't seems to be registered on emsc-csem, the question is how big was this earthquake and what was the distance.
If it was smaller then mag 4.5 it might explain why the earthquake isn't registered anywhere.
Regards.
Subject: Re: Fw: USGS
From: "Dale Hardy" photon1@...........
Date: Thu, 17 Aug 2006 18:59:34 +1000
Hello Jon
i can't pick the 'P' or 'S' times however another station
http://www.map.id.au/seismic/
recorded it approx 40secs earlier
thanks
Dale
----- Original Message -----=20
From: J=F3n Fr=EDmann=20
To: psn-l@.................
Sent: Thursday, August 17, 2006 5:55 PM
Subject: Re: Fw: USGS
Hi
Dale Hardy, I monitor two of your plots (trugh the gif image you =
provide online) and I did see the earthquake.=20
However, it doesn't seems to be registered on emsc-csem, the question =
is how big was this earthquake and what was the distance.=20
If it was smaller then mag 4.5 it might explain why the earthquake =
isn't registered anywhere.
Regards.
--=20
J=F3n Fr=EDmann
http://www.jonfr.com
http://www.simnet.is/jonfr500/earthquake/
=20
-------------------------------------------------------------------------=
-----
No virus found in this incoming message.
Checked by AVG Free Edition.
Version: 7.1.405 / Virus Database: 268.11.1/421 - Release Date: =
16/08/2006
Hello Jon
i can't pick the 'P' or 'S' times =
however another=20
station
http://www.map.id.au/seismic/<=
/FONT>
recorded it approx 40secs =
earlier
thanks
Dale
----- Original Message -----
From:=20
J=F3n =
Fr=EDmann=20
Sent: Thursday, August 17, 2006 =
5:55=20
PM
Subject: Re: Fw: USGS
Hi
Dale Hardy, I monitor two of your plots =
(trugh the=20
gif image you provide online) and I did see the earthquake. =
However, it=20
doesn't seems to be registered on emsc-csem, the question is how big =
was this=20
earthquake and what was the distance.
If it was smaller then mag =
4.5 it=20
might explain why the earthquake isn't registered=20
anywhere.
Regards.
No virus found in this incoming message.
Checked by AVG Free =
Edition.
Version: 7.1.405 / Virus Database: 268.11.1/421 - Release =
Date:=20
16/08/2006
Subject: Re: Fw: USGS
From: "Marchal van Lare" vanlare@.............
Date: Thu, 17 Aug 2006 11:08:48 +0200
Hi folks,
Probably this is the event you are looking for:
http://www.emsc-csem.org/index.php?page=3Dcurrent&sub=3Dmtsol&id=3DNF122;=
MT
WEST OF MACQUARIE ISLAND
Best regards,
Marchal van Lare
www.regioweer.info
----- Original Message -----=20
From: Dale Hardy=20
To: psn-l@.................
Sent: Thursday, August 17, 2006 10:59 AM
Subject: Re: Fw: USGS
Hello Jon
i can't pick the 'P' or 'S' times however another station
http://www.map.id.au/seismic/
recorded it approx 40secs earlier
thanks
Dale
----- Original Message -----=20
From: J=F3n Fr=EDmann=20
To: psn-l@.................
Sent: Thursday, August 17, 2006 5:55 PM
Subject: Re: Fw: USGS
Hi
Dale Hardy, I monitor two of your plots (trugh the gif image you =
provide online) and I did see the earthquake.=20
However, it doesn't seems to be registered on emsc-csem, the =
question is how big was this earthquake and what was the distance.=20
If it was smaller then mag 4.5 it might explain why the earthquake =
isn't registered anywhere.
Regards.
--=20
J=F3n Fr=EDmann
http://www.jonfr.com
http://www.simnet.is/jonfr500/earthquake/
=20
-------------------------------------------------------------------------=
---
No virus found in this incoming message.
Checked by AVG Free Edition.
Version: 7.1.405 / Virus Database: 268.11.1/421 - Release Date: =
16/08/2006
Hi folks,
Probably this is the event you are =
looking=20
for:
http://www.emsc-csem.org/index.php?page=3Dcurrent&=
;sub=3Dmtsol&id=3DNF122;MT
WEST OF MACQUARIE ISLAND
Best regards,
Marchal van Lare
----- Original Message -----
From:=20
Dale Hardy=20
Sent: Thursday, August 17, 2006 =
10:59=20
AM
Subject: Re: Fw: USGS
Hello Jon
i can't pick the 'P' or 'S' times =
however another=20
station
http://www.map.id.au/seismic/<=
/FONT>
recorded it approx 40secs =
earlier
thanks
Dale
----- Original Message -----
From:=20
J=F3n Fr=EDmann=20
Sent: Thursday, August 17, =
2006 5:55=20
PM
Subject: Re: Fw: USGS
Hi
Dale Hardy, I monitor two of your plots =
(trugh the=20
gif image you provide online) and I did see the earthquake. =
However, it=20
doesn't seems to be registered on emsc-csem, the question is how big =
was=20
this earthquake and what was the distance.
If it was smaller =
then mag=20
4.5 it might explain why the earthquake isn't registered=20
anywhere.
Regards.
No virus found in this incoming message.
Checked by AVG =
Free=20
Edition.
Version: 7.1.405 / Virus Database: 268.11.1/421 - =
Release Date:=20
16/08/2006
Subject: Re: Fw: USGS
From: =?ISO-8859-1?Q?J=F3n_Fr=EDmann?= jonfr500@.........
Date: Thu, 17 Aug 2006 09:34:52 +0000
Hi
Checking the raw message, it might be.
http://www.emsc-csem.org/index.php?page=current&sub=mtfull&id=GADH9
But I wonder why this event isn't registerd anyway, execpt in raw data.
Regards.
--
Jón Frímann
http://www.jonfr.com
http://www.simnet.is/jonfr500/earthquake/
Hi
Checking the raw message, it might be. http://www.emsc-csem.org/index.php?page=current&sub=mtfull&id=GADH9
But I wonder why this event isn't registerd anyway, execpt in raw data.
Regards.
Subject: Re: Fw: USGS
From: "Marchal van Lare" vanlare@.............
Date: Thu, 17 Aug 2006 13:01:15 +0200
Hi,
It is missing on other recent lists. Have no clue what happened with =
this event.
Regards,
Marchal van Lare
www.regioweer.info
----- Original Message -----=20
From: J=F3n Fr=EDmann=20
To: psn-l@.................
Sent: Thursday, August 17, 2006 11:34 AM
Subject: Re: Fw: USGS
Hi
Checking the raw message, it might be. =
http://www.emsc-csem.org/index.php?page=3Dcurrent&sub=3Dmtfull&id=3DGADH9=
But I wonder why this event isn't registerd anyway, execpt in raw =
data.
Regards.
--=20
J=F3n Fr=EDmann
http://www.jonfr.com
http://www.simnet.is/jonfr500/earthquake/
=20
Hi,
It is missing on other recent lists. =
Have no clue=20
what happened with this event.
Regards,
Marchal van Lare
----- Original Message -----
From:=20
J=F3n =
Fr=EDmann=20
Sent: Thursday, August 17, 2006 =
11:34=20
AM
Subject: Re: Fw: USGS
Hi
Checking the raw message, it might be. http://www.emsc-csem.org/index.php?page=3Dcurrent&s=
ub=3Dmtfull&id=3DGADH9
But=20
I wonder why this event isn't registerd anyway, execpt in raw=20
data.
Regards.
Subject: Re: Fw: USGS
From: =?ISO-8859-1?Q?J=F3n_Fr=EDmann?= jonfr500@.........
Date: Thu, 17 Aug 2006 17:14:28 +0000
Hi
emsc-csem has finally added the earthquake to there list. With data from
NEIR,
http://www.emsc-csem.org/index.php?page=current&sub=detail&id=NG644;NEIR
Regards.
--
Jón Frímann
http://www.jonfr.com
http://www.simnet.is/jonfr500/earthquake/
Hi
emsc-csem has finally added the earthquake to there list. With data from NEIR, http://www.emsc-csem.org/index.php?page=current&sub=detail&id=NG644;NEIR
Regards.
Subject: Re USGS
From: Dave Nelson davenn@...............
Date: Fri, 18 Aug 2006 06:55:50 +1000
USGA finally rerleased the data for that event ... only 2 days later :)
2006/08/16 16:53 M 5.9 MACQUARIE ISLAND Z= 10km 58.99S 149.03E
This information is provided by the USGS
National Earthquake Information Center.
(Address problems to: sedas@....................
These parameters are preliminary and subject to revision.
A magnitude 5.9 earthquake WEST OF MACQUARIE ISLAND has occurred at:
58.99S 149.03E Depth 10km Wed Aug 16 16:53:49 2006 UTC
Cheers
Dave N
--
No virus found in this outgoing message.
Checked by AVG Free Edition.
Version: 7.1.405 / Virus Database: 268.11.1/421 - Release Date: 16/08/2006
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Deteced a earthquake, can't see p and s wave
From: =?ISO-8859-1?Q?J=F3n_Fr=EDmann?= jonfr500@.........
Date: Thu, 17 Aug 2006 21:32:04 +0000
Hi all
Today I did detect the mb5.9 SAKHALIN ISLAND, RUSSIA earthquake. I don't
see the p and s wave in the trace, however when I check the fft window I
can cleary see the earthquake in the lower frequancyes as expected. I
find this unusual, but it might not be that becose I am using 4.5Hz
geophone. The question that I am wondering about, is this the earthquake
or just noise ?
Regards.
--
Jón Frímann
http://www.jonfr.com
http://www.simnet.is/jonfr500/earthquake/
Hi all
Today I did detect the mb5.9 SAKHALIN ISLAND, RUSSIA earthquake. I don't see the p and s wave in the trace, however when I check the fft window I can cleary see the earthquake in the lower frequancyes as expected. I find this unusual, but it might not be that becose I am using 4.5Hz geophone. The question that I am wondering about, is this the earthquake or just noise ?
Regards.
Subject: Frequancy of earthquake
From: =?ISO-8859-1?Q?J=F3n_Fr=EDmann?= jonfr500@.........
Date: Fri, 18 Aug 2006 01:20:51 +0000
Hi
What frequancyes can I expect to detect at the range of 500 - 2000 km ?
(Using 4.5Hz geophone)
Regards.
--
Jón Frímann
http://www.jonfr.com
http://www.simnet.is/jonfr500/earthquake/
Hi
What frequancyes can I expect to detect at the range of 500 - 2000 km ? (Using 4.5Hz geophone)
Regards.
Subject: Email addresses
From: "Stephen Hammond" shammon1@.............
Date: Fri, 18 Aug 2006 08:40:24 -0700
[Stephen Hammond] S--
Subject: Intresting earthquake swarm in Iceland
From: =?ISO-8859-1?Q?J=F3n_Fr=EDmann?= jonfr500@.........
Date: Sat, 19 Aug 2006 02:16:43 +0000
Hi all
There is a intresting earthquake swarm going on in Iceland at the
moment. The main fracture area is located near 66,023 and -18,248. The
largest earthquake recorded so far is mag 3.5 and it was followed by a
dosent or so smaller earthquakes, but there have been smaller
earthquakes happening all day and are still happening every 10 - 45 min
or so. So far there has been recored 67 earthquakes (based on IMO data).
I have been able to detect earthquakes down to ML1.8 during the night. I
subspect that there might be a larger earthquake coming, becose the
smaller earthquakes have been coming more dense and more of them since
this earthquake swarm did start yesterday. The area that is moveing
appears to be a line that is NW-SE, as it appears on the IMO maps.
Regards.
--
Jón Frímann
http://www.jonfr.com
http://www.simnet.is/jonfr500/earthquake/
Hi all
There is a intresting earthquake swarm going on in Iceland at the moment. The main fracture area is located near 66,023 and -18,248. The largest earthquake recorded so far is mag 3.5 and it was followed by a dosent or so smaller earthquakes, but there have been smaller earthquakes happening all day and are still happening every 10 - 45 min or so. So far there has been recored 67 earthquakes (based on IMO data). I have been able to detect earthquakes down to ML1.8 during the night. I subspect that there might be a larger earthquake coming, becose the smaller earthquakes have been coming more dense and more of them since this earthquake swarm did start yesterday. The area that is moveing appears to be a line that is NW-SE, as it appears on the IMO maps.
Regards.
Subject: with a Lehman
From: Mike Speed mike8s2@.........
Date: Mon, 21 Aug 2006 08:39:14 -0700 (PDT)
How much flux in the lehman?
---------------------------------
Talk is cheap. Use Yahoo! Messenger to make PC-to-Phone calls. Great rates starting at 1˘/min.
How much flux in the lehman?
Talk is cheap. Use Yahoo! Messenger to make PC-to-Phone calls. Great rates starting at 1˘/min.
Subject: Re: with a Lehman
From: "Geoffrey" gmvoeth@...........
Date: Mon, 21 Aug 2006 10:31:31 -0700
Is that ROSIN or ACID you are talking about ?
----- Original Message -----
From: "Mike Speed"
To:
Sent: Monday, August 21, 2006 8:39 AM
Subject: with a Lehman
> How much flux in the lehman?
>
>
> ---------------------------------
> Talk is cheap. Use Yahoo! Messenger to make PC-to-Phone calls. Great rates starting at 1˘/min.
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: with a Lehman
From: Dave Nelson davenn@...............
Date: Tue, 22 Aug 2006 07:06:57 +1000
or is it magnetic flux you are talking about ???
Mike
i think you need to ask a better question we alol need a better
idea of what you are
talking about and what you are wanting to know :)
cheers
Dave N
At 10:31 AM 21/08/2006 -0700, you wrote:
>Is that ROSIN or ACID you are talking about ?
>
>----- Original Message ----- From: "Mike Speed"
>To:
>Sent: Monday, August 21, 2006 8:39 AM
>Subject: with a Lehman
>>
>>How much flux in the lehman?
--
No virus found in this outgoing message.
Checked by AVG Free Edition.
Version: 7.1.405 / Virus Database: 268.11.3/423 - Release Date: 18/08/2006
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Digest from 08/21/2006 00:01:48
From: Sampeybill@.............
Date: Wed, 23 Aug 2006 15:06:17 EDT
Please discontinue.
Please discon=
tinue.
Subject: Resistive Damping
From: "Benji Johnson" Benji.Johnson@..................
Date: Wed, 23 Aug 2006 13:30:05 -0700
I would like to update my Lehman style seismometer from that of using oil =
damping to using resistive damping. I have read Sean-Thomas' very =
informative post (http://www.seismicnet.com/psnlist/991109_101841_1.html), =
but being a rank novice in such matters, I still have a few questions.
The coil that I am using is wound with #34 wire, and has a resistance of =
2,330 ohms. The leads from the coil currently terminate in an RCA jack.
My tentative plan is to: 1) Short the leads, to determine if resistive =
damping will be feasible. 2) Begin with approximately 3,000 ohms of =
resistance and begin a trial & error period to determine the appropriate =
amount of resistance.
The questions that I have before starting in on this are:
1) Is there a technique to cutting through the insulation to get to the =
wires? I get nervous thinking about working with the fine #34 wire, and =
having to rewire the RCA jack due to a careless mistake. Is it just a =
matter of careful scraping to get to the wire?
2) Once down to the wire, what is the best way to go about connecting the =
resistors to the leads? With alligator clips, which would make it easily =
removable?
3) I know that the resistors need to be wired in parallel, but what is =
the best way to connect the resistors to each other? Twist together, =
solder, or use a solderless breadboard mounted between the leads?
Thanks in advance.
Benji Johnson
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Resistive Damping
From: John Popelish jpopelish@........
Date: Wed, 23 Aug 2006 19:21:31 -0400
Benji Johnson wrote:
(snip)
> The coil that I am using is wound with #34 wire, and has a resistance of 2,330 ohms.
> 1) Is there a technique to cutting through the insulation to get to the wires?
I use a butane lighter to burn the insulation off, followed by a light
abrasion by pulling the end from a folded fine sandpaper (600 grit
silicon carbide). Then it can easily be tinned.
> 2) Once down to the wire, what is the best way to go about connecting the resistors to the leads?
I would solder to a pair of flexible lead wires that are anchored to
the coil with tape.
> 3) I know that the resistors need to be wired in parallel,
> but what is the best way to connect the resistors to each other?
> Twist together, solder, or use a solderless breadboard mounted
between the leads?
You might start with a variable resistor soldered to the lead wires.
That makes adjustment very easy. Once you have found the desired
response, select a standard resistor with about that value, to replace
the adjustable. You can connect that final resistor to the terminals
on the jack that the lead wires terminate on.
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: WinSDR fails to replay
From: "Thomas Dick" dickthomas01@.............
Date: Wed, 23 Aug 2006 18:50:54 -0500
Has anyone had this problem? The electricity was off for an hour and came
on. Then about an hour later it shut down/or spiked for a millisecond. After
that I couldn't access the replay function in WinSDR. What I mean is that if
I hit the repeat function and set a time after the "interreuptionI", I get
nothing but a blank replay screen. Before the event, the data is produced as
it normally is in the replay mode. I turn off the computer. I reinstalled
WINSDR and even Winquake. If I look at the data folder I can see the file
being updated about every minute so the data is being saved. The fact that I
could reinstall WinSDR and Winquake would indicated the hard drive is ok,
right?
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Resistive Damping
From: ChrisAtUpw@.......
Date: Wed, 23 Aug 2006 22:15:09 EDT
In a message dated 23/08/06, Benji.Johnson@.................. writes:
> I would like to update my Lehman style seismometer from that of using oil
> damping to using resistive damping
Hi Benji,
Electromagnetic damping is easy to adjust and it is not temperature
sensitive, or messy.
> 1) Is there a technique to cutting through the insulation to get to the
> wires? I get nervous thinking about working with the fine #34 wire, and having
> to rewire the RCA jack due to a careless mistake. Is it just a matter of
> careful scraping to get to the wire?
You can use a pad of wire wool to remove insulation. However, most
fine wires now have polyurethane insulation, which simply melts when you put a
hot soldering iron on it. This makes the job a lot easier! You can also burn
insulation off with a gas lighter, with some care, but this leaves the wire very
soft and you need to clean it with wire wool.
It is probably best to solder a suitable 20 turn pre-set cermet
potentiometer across the terminals on the baseplate. You need to adjust the damping
whenever you disassemble the arm and then reset the period.
However, putting a resistance in parallel with the coil does reduce
the signal. It also depends on your having a strong even magnetic field around
the coil. Commercial seismometers may have a magnet / coil setup similar to a
loudspeaker. Sean used this type, but he wound his own coils. This requires
quite a bit of skill, time and effort, in case you haven't tried it. If you are
just using a U Alnico magnet and a relay coil, you are very unlikely to get
enough output. I don't think that inexpensive NdFeB magnets were so plentiful
back in 1999, so I would now question Sean's assertion that this is the easiest /
most satisfactory method.
It is quite easy to fit the mass with a horizontal copper tongue,
maybe 2.5" long by 2" wide and use a variable position damping magnet. You can
probably 'get away' with using 32 thou Cu plate, although I use 1/16" thick for
preference. You buy 4 off NdFeB bar magnets, 1" x 1/2" x 1/4". See
http://www.kjmagnetics.com/ You need 2 off bright mild steel backing plates 2" wide x 3.5"
long x 1/4" thick and four 2.5" long zinc plated mild steel 1/4" set screws,
each with a washer and three nuts. Set screws are completely threaded. The
backing plate is sold as 2" wide rolled strip.
You mark out the 4 drill holes 5/16" in from the corners on one plate,
clamp the plates together and then drill 1/4" holes through both. This gets
the holes perfectly aligned. Mark the plates so that you know which way to
reassemble them. You put a washer on one screw, push it through a hole and fix it
in place with a nut. Then you screw on another nut to maybe 1" from the plate.
Repeat at the other corners and assemble with the magnets as shown below.
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX Backing plate
NNNNNSSSSS Magnets
<--cucucucucucucucucucucucucucucu--> Damping tongue
SSSSSNNNNN
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
The Cu tongue moves perpendicular to the 1" magnet joints. You adjust
the damping both by varying the separation of the magnets with the adjusting
nuts and by sliding the magnet block further over the Copper tongue. The Cu
tongue overlaps the magnets laterally at all times. This avoids any diamagnetic
'edge effects'.
Note that the amount of damping required decreases, as you increase
the set period. If you displace the mass by 10 mm and then release it, 0.7
critical damping allows the mass to swing ~0.5 mm past the centre balance position
before falling back.
The magnets can pick up dust particles from the air. To clean them, I
press on Gaffer tape and then peel it off. The rubbery adhesive seems to
remove dust particles very well.
Regards,
Chris Chapman
In a me=
ssage dated 23/08/06, Benji.Johnson@.................. writes:
I would like to update my Lehma=
n style seismometer from that of using oil damping to using resistive dampin=
g
Hi Benji,
Electromagnetic damping is easy to adju=
st and it is not temperature sensitive, or messy.
1) Is there a technique to cutt=
ing through the insulation to get to the wires? I get nervous thinking=
about working with the fine #34 wire, and having to rewire the RCA jack due=
to a careless mistake. Is it just a matter of careful scraping to get=
to the wire?
You can use a pad of wire wool to remov=
e insulation. However, most fine wires now have polyurethane insulation, whi=
ch simply melts when you put a hot soldering iron on it. This makes the job=20=
a lot easier! You can also burn insulation off with a gas lighter, with some=
care, but this leaves the wire very soft and you need to clean it with wire=
wool.
It is probably best to solder a suitabl=
e 20 turn pre-set cermet potentiometer across the terminals on the baseplate=
.. You need to adjust the damping whenever you disassemble the arm and then r=
eset the period.
However, putting a resistance in parall=
el with the coil does reduce the signal. It also depends on your having a st=
rong even magnetic field around the coil. Commercial seismometers may have a=
magnet / coil setup similar to a loudspeaker. Sean used this type, but he w=
ound his own coils. This requires quite a bit of skill, time and effort, in=20=
case you haven't tried it. If you are just using a U Alnico magnet and a rel=
ay coil, you are very unlikely to get enough output. I don't think that inex=
pensive NdFeB magnets were so plentiful back in 1999, so I would now questio=
n Sean's assertion that this is the easiest / most satisfactory method.
It is quite easy to fit the mass with a=
horizontal copper tongue, maybe 2.5" long by 2" wide and use a variable pos=
ition damping magnet. You can probably 'get away' with using 32 thou Cu plat=
e, although I use 1/16" thick for preference. You buy 4 off NdFeB bar magnet=
s, 1" x 1/2" x 1/4". See http://www.kjmagnetics.com/ You need 2 off bright m=
ild steel backing plates 2" wide x 3.5" long x 1/4" thick and four 2.5" long=
zinc plated mild steel 1/4" set screws, each with a washer and three nuts.=20=
Set screws are completely threaded. The backing plate is sold as 2" wide rol=
led strip.
You mark out the 4 drill holes 5/16" in=
from the corners on one plate, clamp the plates together and then drill 1/4=
" holes through both. This gets the holes perfectly aligned. Mark the plates=
so that you know which way to reassemble them. You put a washer on one scre=
w, push it through a hole and fix it in place with a nut. Then you screw on=20=
another nut to maybe 1" from the plate. Repeat at the other corners and asse=
mble with the magnets as shown below.
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX B=
acking plate
&nbs=
p; &n=
bsp; NNNNNSSSSS &=
nbsp; Magn=
ets
<--cucucucucucucuc=
ucucucucucucucu--> Damping tongue
&nbs=
p; &n=
bsp; SSSSSNNNNN
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
The Cu tongue moves perpendicular to th=
e 1" magnet joints. You adjust the damping both by varying the separation of=
the magnets with the adjusting nuts and by sliding the magnet block further=
over the Copper tongue. The Cu tongue overlaps the magnets laterally at all=
times. This avoids any diamagnetic 'edge effects'.
Note that the amount of damping require=
d decreases, as you increase the set period. If you displace t=
he mass by 10 mm and then release it, 0.7 critical damping allows the mass t=
o swing ~0.5 mm past the centre balance position before falling back.
The magnets can pick up dust particles=20=
from the air. To clean them, I press on Gaffer tape and then peel it off. Th=
e rubbery adhesive seems to remove dust particles very well.
Regards,
Chris Chapman
Subject: Re: Resistive Damping
From: John or Jan Lahr JohnJan@........
Date: Wed, 23 Aug 2006 22:12:42 -0700
Benji,
I've posted details of Chris Chapman's magnetic damping system here:
http://jclahr.com/science/psn/chapman/as1%20damping/index.html
This is for an AS-1 system, but is easily modified for a Lehman.
Chris' Lehman design is shown here:
http://jclahr.com/science/psn/chapman/lehman/index.html
Cheers,
John
At 07:15 PM 8/23/2006, you wrote:
>In a message dated 23/08/06, Benji.Johnson@.................. writes:
>
>>I would like to update my Lehman style seismometer from that of
>>using oil damping to using resistive damping
>
>
>Hi Benji,
>
> Electromagnetic damping is easy to adjust and it is not
> temperature sensitive, or messy.
....
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Resistive Damping
From: "James Hannon" jmhannon@.........
Date: Thu, 24 Aug 2006 07:05:27 -0500
There is really no reason to cut into the wires to add the damping resistor. Just connect the resistor across whatever the RCA plug is connected to.
Jim H
---------- Original Message ----------------------------------
From: John Popelish
Reply-To: psn-l@..............
Date: Wed, 23 Aug 2006 19:21:31 -0400
>Benji Johnson wrote:
>(snip)
>> The coil that I am using is wound with #34 wire, and has a resistance of 2,330 ohms.
>
>> 1) Is there a technique to cutting through the insulation to get to the wires?
>
>I use a butane lighter to burn the insulation off, followed by a light
>abrasion by pulling the end from a folded fine sandpaper (600 grit
>silicon carbide). Then it can easily be tinned.
>
>> 2) Once down to the wire, what is the best way to go about connecting the resistors to the leads?
>
>I would solder to a pair of flexible lead wires that are anchored to
>the coil with tape.
>
>> 3) I know that the resistors need to be wired in parallel,
>> but what is the best way to connect the resistors to each other?
> > Twist together, solder, or use a solderless breadboard mounted
>between the leads?
>
>You might start with a variable resistor soldered to the lead wires.
>That makes adjustment very easy. Once you have found the desired
>response, select a standard resistor with about that value, to replace
>the adjustable. You can connect that final resistor to the terminals
>on the jack that the lead wires terminate on.
>__________________________________________________________
>
>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.
>
--
Jim Hannon
http://www.fmtcs.com/web/jmhannon/
42,11.90N,91,39.26W
WB0TXL
--
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Reykjanes Ridge earthquakes today
From: Tamati chief.cook.nz@............
Date: Mon, 28 Aug 2006 00:05:02 +1200
TAMATI's WORD's OF WISDOM
FOR THE GOOD OF ALL MANKIND
HTTP://LIVE-PLANET.BLOGSPOT.COM
http://www.webspawner.com/users/chiefcooknz/index.html
Please give me feed back on what you think
chief.cook.nz.@............
NZ-021-150-33-59 or NZ-07-855-0195
Sir
Where is the Reykjanes Ridge please?? it could be very inportant if I'm
right
Cheers Tamati
From the Castle of Tamati, Hinemoa and Karauwa the Dog
From the Castle of Tom, Robyn and the Dog
I'm Just a Stone's Throw Away:- NZ-021-150-33-59 or NZ-07-855-0195
Bush Telegragh:- chief.cook.nz@............
My Regular Pitstop:- Tamati
P.O.BOX
19-356 CENTRAL
HAMILTON
NEW
ZEALAND
----- Original Message -----
From: "Jón Frímann"
To: "PSN-Postlist"
Sent: Saturday, July 29, 2006 1:21 PM
Subject: Reykjanes Ridge earthquakes today
> Hi all
>
> Today there where three earthquakes out to the Reykjanes Ridge, this is
> not the first time I have recored earthquakes from that area. But I did
> record two earthquakes from that area in Febuary this year. But then I
> didn't see the p and s wave as I did today. The only thing I have
> changed in the meantime is the cable and I have ground connected the
> cable. It surprices me that it did make such huge diffrent as it
> apperently did.
>
> Regards.
> --
> Jón Frímann
> http://www.jonfr.com
> http://www.simnet.is/jonfr500/earthquake/
>
> __________________________________________________________
>
> 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: ebay auction
From: Bob Barns royb1@...........
Date: Sun, 27 Aug 2006 10:27:59 -0400
Hi gang,
Sprengnether 3 Axis Seismometer
Item number: 220021515849
ends Sept. 2
Bob
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Reykjanes Ridge earthquakes today
From: =?ISO-8859-1?Q?J=F3n_Fr=EDmann?= jonfr500@.........
Date: Sun, 27 Aug 2006 15:19:10 +0000
Hi
Reykjanes ridge is south of Iceland.
Regards.
--
Jón Frímann
http://www.jonfr.com
http://www.simnet.is/jonfr500/earthquake/
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: ebay auction
From: "Jerry Payton" gpayton880@.......
Date: Sun, 27 Aug 2006 10:47:07 -0500
Anyone have any details on this instrument?
Examining a close-up of the photo, it seems to have a number 314/535-1682 on
it. I cannot find a website to check if that is a model number or not.
Regards,
Jerry Payton
----- Original Message -----
From: Bob Barns
To: psn mail
Sent: Sunday, August 27, 2006 9:27 AM
Subject: ebay auction
Hi gang,
Sprengnether 3 Axis Seismometer
Item number: 220021515849
ends Sept. 2
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.
Anyone have any details on this instrument?
Examining a close-up of the photo, it seems to have a number =
314/535-1682=20
on it. I cannot find a website to check if that is a model number =
or=20
not.
Regards,
Jerry Payton
----- Original Message -----
From:=20
Bob =
Barns=20
Sent: Sunday, August 27, 2006 =
9:27=20
AM
Subject: ebay auction
Hi gang,
Sprengnether 3 Axis=20
Seismometer
Item number: 220021515849
ends Sept.=20
=
2
Bob
_________________________________________________________=
_
Public=20
Seismic Network Mailing List (PSN-L)
To leave this list email =
PSN-L-REQUEST@...............
=20
with
the body of the message (first line only): unsubscribe
See =
http://www.seismicnet.co=
m/maillist.html=20
for more information.
Subject: Re: ebay auction
From: ChrisAtUpw@.......
Date: Sun, 27 Aug 2006 13:15:20 EDT
In a message dated 27/08/06, gpayton880@....... writes:
> Anyone have any details on this instrument?
>
Hi,
With this size aand shape it has to be a strong motion accelerometer.
Regards,
Chris Chapman
In a me=
ssage dated 27/08/06, gpayton880@....... writes:
Anyone have any details on this=
instrument?
Hi,
With this size aand shape it has to be=20=
a strong motion accelerometer.
Regards,
Chris Chapman
Subject: Three most active volcanos in Iceland are heating up
From: =?ISO-8859-1?Q?J=F3n_Fr=EDmann?= jonfr500@.........
Date: Thu, 31 Aug 2006 19:58:45 +0000
Hi all
According to Icelandic news it appeears that three most active volcanos
in Iceland are heating up. But that are Grimsvotn (Grimsfjall),
Myrdalsjokull, Hekla. Volcano named Bardarbunga is also starting to show
signs of incresed activite, but nothing conclusive yet. Helka has been
erupting every ten year since 1970, last eruption was in 2000.
Grimsfjall did last erupt in 2004. Myrdalsjokull last eruption was in
1918. Bardarbunga did last erupt in 1903.
When thease volcanos erupts I am problay going to see some of the
activie on my sensor, how much exacly is unkown to me. I am going to
record the eruption releated earthquakes for sure (above mag 2.8) when
the time comes.
Regards.
--
Jón Frímann
http://www.jonfr.com
http://www.simnet.is/jonfr500/earthquake/
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Out of office
From: "service01@............. henry@tenorgeo.com
Date: Thu, 31 Aug 2006 14:58:56 -0500
Hello. I'll be working in the field until Friday September 1. Should you need to contact me urgently, please call me by phone and leave a message.
Thanks,
Henry Bland
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Three most active volcanos in Iceland are heating up
From: "Geoffrey" gmvoeth@...........
Date: Thu, 31 Aug 2006 18:11:51 -0700
This is all quite interesting.
However I do not understand how magma
which has seperated from its source of
energy deep inside the Earth can be "HEATING UP"
It seems to me that from the time it begins
its bouyant travels melting through the
Earths Crust to reach the surface it
will be cooling all the way.
Maybe what you are saying here is that
the magma chamber is expanding or
something like that.
I do, however, understand the meaning of
increased activity.
Regards;
geoff
----- Original Message -----
From: "Jón Frímann"
To: "PSN-Postlist"
Sent: Thursday, August 31, 2006 12:58 PM
Subject: Three most active volcanos in Iceland are heating up
> Hi all
>
> According to Icelandic news it appeears that three most active volcanos
> in Iceland are heating up. But that are Grimsvotn (Grimsfjall),
> Myrdalsjokull, Hekla. Volcano named Bardarbunga is also starting to show
> signs of incresed activite, but nothing conclusive yet. Helka has been
> erupting every ten year since 1970, last eruption was in 2000.
> Grimsfjall did last erupt in 2004. Myrdalsjokull last eruption was in
> 1918. Bardarbunga did last erupt in 1903.
>
> When thease volcanos erupts I am problay going to see some of the
> activie on my sensor, how much exacly is unkown to me. I am going to
> record the eruption releated earthquakes for sure (above mag 2.8) when
> the time comes.
>
> Regards.
> --
> Jón Frímann
> http://www.jonfr.com
> http://www.simnet.is/jonfr500/earthquake/
>
> __________________________________________________________
>
> 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: Out of office
From: "service01@............. henry@tenorgeo.com
Date: Thu, 31 Aug 2006 20:12:12 -0500
Hello. I'll be working in the field until Friday September 1. Should you need to contact me urgently, please call me by phone and leave a message.
Thanks,
Henry Bland
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Public Seismic Network Mailing List (PSN-L)
Subject: Re: Three most active volcanos in Iceland are heating up
From: =?ISO-8859-1?Q?J=F3n_Fr=EDmann?= jonfr500@.........
Date: Fri, 01 Sep 2006 01:39:21 +0000
Hi
It's an expression, it measns that the volcanos are getting ready to
erupt, the magma it self isn't heating up. However some of it might get
a exsplosive if it has been accomulating for a long time in the magma
chamber. Hekla magma chamber is already full, according to the news,
however it might to overpressure before it erupts. It is unceartin what
exacly is happening in Myrdalsjokull but that volcano has been
collecting magma for long time now. Grimsvotn are in the early stages of
collecting magma into the magma chamber, but there are clear evidence of
that happening according to the news.
Regards.
--
Jón Frímann
http://www.jonfr.com
http://www.simnet.is/jonfr500/earthquake/
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Public Seismic Network Mailing List (PSN-L)
Subject: For sale Lehman Seismometer
From: 1goss@...........
Date: Fri, 01 Sep 2006 22:24:20 +0000
For sale Lehman Seismometer
Listed are prices I paid Larry for the electronics
Garmin GPS 18-LVC OEM Timing System $98.00
Version II Board with 26 Pin Ribbon Connector Header $180.00
2ch Independent Amplifier / Filter board $110.00
Pickup Coil and Magnet for Lehman Sensor $20.00
Complete base plates weight and vertical damping system all pictured in # 6 Jpg picture.
I would like to get at least $425.00 + shipping I will take best offer made for 425.00 or more. I do have a paypal account if preferred.
This is a good bit less than I have in it + it should not take much to get it back going again.
Misc Pics of the system
https://home.comcast.net/~bryangoss/1.jpg
https://home.comcast.net/~bryangoss/2.jpg
https://home.comcast.net/~bryangoss/3.jpg
https://home.comcast.net/~bryangoss/4.jpg
https://home.comcast.net/~bryangoss/5.jpg
https://home.comcast.net/~bryangoss/6.jpg
To contact me directly you can email me at 1goss@...........
Bryan S Goss
Corinth Ms, 38834
Phone 662-287-5341
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Public Seismic Network Mailing List (PSN-L)
Subject: Risk of a large earthquake in California soon
From: =?ISO-8859-1?Q?J=F3n_Fr=EDmann?= jonfr500@.........
Date: Sat, 02 Sep 2006 12:05:27 +0000
Hi all
I do think that there is a risk of a moderate to strong earthquake in
Northen part of California soon. I base that on sudden increase in minor
earthquakes, but I have been monitoring Larry sensors, specally the USGS
one. However, the fastest increase was today, early this morning GMT
time when several earthquakes that are below 2.5 mag did appear over a 7
hour period (as it stands now), ending with a earthquake that was mag
2.5 in size at 11:25.
I do not know how accurate this is. It is just wait and see thing.
Regards.
--
Jón Frímann
http://www.jonfr.com
http://www.simnet.is/jonfr500/earthquake/
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Risk of a large earthquake in California soon
From: Alexandr Yagodin midia@..............
Date: Sat, 02 Sep 2006 15:44:08 +0200
Dear Jon!
I can predict earthquake precisely more, than after some hours prior to the
beginning. (Time, place and force).
At me the examination of the Russian academy of sciences is made, but your
scientist and it is not necessary for government.
Alexandr Yagodin
----- Original Message -----
From: "Jón Frímann"
To: "PSN-Postlist"
Sent: Saturday, September 02, 2006 2:05 PM
Subject: Risk of a large earthquake in California soon
> Hi all
>
> I do think that there is a risk of a moderate to strong earthquake in
> Northen part of California soon. I base that on sudden increase in minor
> earthquakes, but I have been monitoring Larry sensors, specally the USGS
> one. However, the fastest increase was today, early this morning GMT
> time when several earthquakes that are below 2.5 mag did appear over a 7
> hour period (as it stands now), ending with a earthquake that was mag
> 2.5 in size at 11:25.
>
> I do not know how accurate this is. It is just wait and see thing.
>
> Regards.
> --
> Jón Frímann
> http://www.jonfr.com
> http://www.simnet.is/jonfr500/earthquake/
>
> __________________________________________________________
>
> 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: Risk of a large earthquake in California soon
From: "Geoffrey" gmvoeth@...........
Date: Sat, 2 Sep 2006 09:03:12 -0700
Why is it so important to predict EQ.
It is much more important to build for
and avoid the inevitable.
If you know where they are then you can
use your smarts to plan in dealing with them
instead of wasting valuable resources trying to predict
the inevitable.
It (Exact prediction) is sort of a misdirection in the application
of valuable resources.
This is true of all dangerous natural phenomena
and not just EQs.
----- Original Message -----
From: "Alexandr Yagodin"
To:
Sent: Saturday, September 02, 2006 6:44 AM
Subject: Re: Risk of a large earthquake in California soon
> Dear Jon!
>
> I can predict earthquake precisely more, than after some hours prior to the
> beginning. (Time, place and force).
>
> At me the examination of the Russian academy of sciences is made, but your
> scientist and it is not necessary for government.
>
> Alexandr Yagodin
>
>
>
> ----- Original Message -----
> From: "Jón Frímann"
> To: "PSN-Postlist"
> Sent: Saturday, September 02, 2006 2:05 PM
> Subject: Risk of a large earthquake in California soon
>
>
>> Hi all
>>
>> I do think that there is a risk of a moderate to strong earthquake in
>> Northen part of California soon. I base that on sudden increase in minor
>> earthquakes, but I have been monitoring Larry sensors, specally the USGS
>> one. However, the fastest increase was today, early this morning GMT
>> time when several earthquakes that are below 2.5 mag did appear over a 7
>> hour period (as it stands now), ending with a earthquake that was mag
>> 2.5 in size at 11:25.
>>
>> I do not know how accurate this is. It is just wait and see thing.
>>
>> Regards.
>> --
>> Jón Frímann
>> http://www.jonfr.com
>> http://www.simnet.is/jonfr500/earthquake/
>>
>> __________________________________________________________
>>
>> 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: Risk of a large earthquake soon
From: ChrisAtUpw@.......
Date: Sat, 2 Sep 2006 20:46:14 EDT
In a message dated 02/09/06, gmvoeth@........... writes:
> Why is it so important to predict EQ. It is much more important to build
> for
> and avoid the inevitable.
Hi Geoff,
I agree entirely of the need to plan buildings, bridges, power lines,
water supplies etc to be earthquake resistant. But there are limits to what
can be done in practice.
Do you knock down much of San Francisco and rebuild it to a higher
standard and if so, what quake level do you plan for and who pays for it? Do you
rebuild it somewhere else, where the risks are much less? Do you provide
earthquake shelters in 'at risk' private dwellings, like the bomb shelters
distributed during WW II?
> If you know where they are then you can use your smarts to plan in dealing
> with them instead of wasting valuable resources trying to predict the
> inevitable.
However, if we could get even a few minutes warning of really damaging
quakes and communicate this to people in the areas likely to be effected, a
great many lives could be saved. While the quakes are no doubt inevitable,
death and injury from them are not. It is largely falling buildings which kill
people, not the quakes themselves.
I am not entirely sure what resources are being 'wasted' at the
moment? I suspect that the total effort is 'significantly less than might be
prudent'.
> It (Exact prediction) is sort of a misdirection in the application of
> valuable resources.
This assumes that it can't be done. I don't think that seismology has
yet developed anywhere near to a stage where this can be determined. It may
also be the case that some but not all quakes will be ~predictable. We might as
well do what we can, but if we don't at least try, we can't succeed.
> This is true of all dangerous natural phenomena and not just EQs.
>
Then how do you view Hurricane and Tornado weather prediction? It
certainly isn't 100% accurate, but how much worse off would we be without it? The
catastrophy at New Orleans was at least partially due to political problems.
The authorities were not even able to fill up the available school buses and
drive them to safety! Should a bunch of them now be in jail for 'corporate
manslaughter'?
Regards,
Chris Chapman
In a me=
ssage dated 02/09/06, gmvoeth@........... writes:
Why is it so important to predi=
ct EQ. It is much more important to build for
and avoid the inevitable.
Hi Geoff,
I agree entirely of the need to plan bu=
ildings, bridges, power lines, water supplies etc to be earthquake resistant=
.. But there are limits to what can be done in practice.
Do you knock down much of San Francisco=
and rebuild it to a higher standard and if so, what quake level do you plan=
for and who pays for it? Do you rebuild it somewhere else, where the risks=20=
are much less? Do you provide earthquake shelters in 'at risk' private dwell=
ings, like the bomb shelters distributed during WW II?
If you know where they are then=
you can use your smarts to plan in dealing with them instead of wasting val=
uable resources trying to predict the inevitable.
However, if we could get even a few mi=
nutes warning of really damaging quakes and communicate this to people in th=
e areas likely to be effected, a great many lives could be saved. While the=20=
quakes are no doubt inevitable, death and injury from them are not. It is la=
rgely falling buildings which kill people, not the quakes themselves.
I am not entirely sure what resources a=
re being 'wasted' at the moment? I suspect that the total effort is 'signifi=
cantly less than might be prudent'.
It (Exact prediction) is sort o=
f a misdirection in the application of valuable resources.
This assumes that it can't be done. I=20=
don't think that seismology has yet developed anywhere near to a stage where=
this can be determined. It may also be the case that some but not all quake=
s will be ~predictable. We might as well do what we can, but if we don't at=20=
least try, we can't succeed.
This is true of all dangerous n=
atural phenomena and not just EQs.
Then how do you view Hurricane and Torn=
ado weather prediction? It certainly isn't 100% accurate, but how much worse=
off would we be without it? The catastrophy at New Orleans was at least par=
tially due to political problems. The authorities were not even able to fill=
up the available school buses and drive them to safety! Should a bunch of t=
hem now be in jail for 'corporate manslaughter'?
Regards,
Chris Chapman
Subject: Re: Risk of a large earthquake soon
From: "Geoffrey" gmvoeth@...........
Date: Sun, 3 Sep 2006 07:54:54 -0700
Hello Chris Thanks for your reply;
Yes it would be very expensive to build
properly for natural disasters but what you
do is correct the mistakes of the past
as time goes on. As buildings get old and die you
either move to a safer location or build a
better stronger building. But I have seen well
built Japanese buildings simply fall over
like a big tree and not otherwise seem damaged
in a case such as this a new location is needed
or the roots of the building need to be so deep
that liquification is irrelevent.
Peoples of the past were extremely ignorant of the universe
around them and tend to build in the most
beautiful inviting places that are the
result of on going natural disasters.
It seems the place currently known as Atlantis
was originally constructed in the very heart of
an Active volcano because for one reason or another
these folks found it out of ignorance to be an ideal place.
There exists a problem no one is willing to address
and that involves overpopulation. It is my personal belief
that all the good livable land is taken and
many people are forced by circumstances
beyond their control to live in dangerous places.
Governments should dedicate themselves to the
health safety and welfare and Education of their citizens
because that is really the primary reason for
their existance if you want to be civilized.
This means dedicating all your financial and
other resources in that direction.
Regards;
Geoff
----- Original Message -----
From:
To:
Sent: Saturday, September 02, 2006 5:46 PM
Subject: Re: Risk of a large earthquake soon
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Risk of a large earthquake in California soon
From: David Sarraf david.sarraf@............
Date: Sun, 03 Sep 2006 17:08:53 -0400
Chris, Jón
The August 21 issue of Electronic Engineering Times has a short article about an earthquake warning system that sends alerts through via cable TV. It is an extension of an existing network that provides alarms to hospitals, schools, and industry. They admit that it may not provide more than a few seconds warning in worst case scenarios but it was felt that even that amount of time was much better than nothing at all. It would be at least enough time to stop a train or find the best place to stand. For more info see www.eetimes.com, search for article ID 0405734.
Dave Sarraf
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Risk of a large earthquake in California soon
From: ChrisAtUpw@.......
Date: Sun, 3 Sep 2006 21:24:42 EDT
In a message dated 2006/09/03, david.sarraf@............ writes:
> The August 21 issue of Electronic Engineering Times has a short article
> about an earthquake warning system that sends alerts through via cable TV. They
> admit that it may not provide more than a few seconds warning in worst case
> scenarios but it was felt that even that amount of time was much better than
> nothing at all. It would be at least enough time to stop a train or find the
> best place to stand. For more info see www.eetimes.com, search for article
Hi David,
I had to sign on, but there are three articles about earthquake /
tsunami / alert warning / systems. They seem to have the most incompetent
registration system that I have yet encountered. And you are prevented from
complaining since the validation display text is not recognised!
With some thousands of sensors around Japan, it is practicable to
sense the first fast P wave. This could give some seconds warning before the
damaging surface waves reach you - maybe enough to dive under the table!
Regards,
Chris Chapman
In a me=
ssage dated 2006/09/03, david.sarraf@............ writes:
The August 21 issue of Electron=
ic Engineering Times has a short article about an earthquake warning system=20=
that sends alerts through via cable TV. They admit that it may not provide m=
ore than a few seconds warning in worst case scenarios but it was felt that=20=
even that amount of time was much better than nothing at all. It would be at=
least enough time to stop a train or find the best place to stand. Fo=
r more info see www.eetimes.com, search for article
Hi David,
I had to sign on, but there are three a=
rticles about earthquake / tsunami / alert warning / systems. They seem to h=
ave the most incompetent registration system that I have yet encountered. An=
d you are prevented from complaining since the validation display text is no=
t recognised!
With some thousands of sensors around J=
apan, it is practicable to sense the first fast P wave. This could give some=
seconds warning before the damaging surface waves reach you - maybe enough=20=
to dive under the table!
Regards,
Chris Chapman
Subject: ebay auction
From: Bob Barns royb1@...........
Date: Mon, 04 Sep 2006 10:44:30 -0400
Hi gang,
Geosonics Inc. Seismograph
Seismic and Acoustic Monitioring System Item number: 270025372888
ends Sept.10
Bob
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Public Seismic Network Mailing List (PSN-L)
Subject: Fwd: [IRIS] 8 Hz geophones, vertical and horizontal, available
From: John or Jan Lahr JohnJan@........
Date: Tue, 05 Sep 2006 14:37:10 -0700
Not too good for distant earthquakes, but the price is right, especially
if you live near Stanford University. These should NOT go into the
landfill!!!
John
>Subject: 8 Hz geophones, vertical and horizontal, available free to a
>good home
>
>
>Stanford University owns a large number of 8 Hz geophones, as used in
>conjunction with the Seismic Group Recorder (SGR-III) facility in
>many PASSCAL experiments from 1980 to 2001.
>
>We have about 200 "short" strings of 6 modified Mark Products L-10B
>vertical-component geophones (8 Hz) connected in series, with c. 1 m
>cable between each phone.
>
>We also own a larger number of "long" strings of 12 L-10B vertical
>phones, or of 12 horizontal phones, in each case with c. 15 m cable
>between each phone, one string per clip.
>
>
>These will be disposed of as scrap/landfill on October 1, unless
>anyone claims them first
>
>
>I can consider offers to take all or any part of our equipment. You
>would need to pay shipping.
>
>If you know of anyone who would want e.g. single geophones for
>teaching/demonstration purposes, please forward this message.
>
>
>~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>Simon Klemperer
>Professor of Geophysics, and of Geological and Environmental Sciences,
>Director of Undergraduate Studies in Geophysics,
>Department of Geophysics, Stanford University,
>Mitchell Building 353, 397 Panama Mall, Stanford CA 94305-2215
>telephone: (650) 723 8214 (secretary: 723 4890) fax : (650) 725
>7344
>sklemp@............ http://geo.stanford.edu/~sklemp/
>~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>
>_______________________________________________
>Bulkmail mailing list
>Bulkmail@...................
>http://www.iris.washington.edu/mailman/listinfo/bulkmail
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: [IRIS] 8 Hz geophones, vertical and horizontal, available free
From: ChrisAtUpw@.......
Date: Tue, 5 Sep 2006 18:39:18 EDT
In a message dated 2006/09/05, JohnJan@........ writes:
> Not too good for distant earthquakes, but the price is right, especially
> if you live near Stanford University. These should NOT go into the
> landfill!!!
> John
>
> >Subject: 8 Hz geophones, vertical and horizontal, available free to a
> >good home
> >Stanford University owns a large number of 8 Hz geophones, as used in
> >conjunction with the Seismic Group Recorder (SGR-III) facility in
> >many PASSCAL experiments from 1980 to 2001.
> >We have about 200 "short" strings of 6 modified Mark Products L-10B
> >vertical-component geophones (8 Hz) connected in series, with c. 1 m
> >cable between each phone.
> >We also own a larger number of "long" strings of 12 L-10B vertical
> >phones, or of 12 horizontal phones, in each case with c. 15 m cable
> >between each phone, one string per clip.
Dear Professor Klemperer,
Have you contacted anyone interested in archaeology? These string
lengths and operating frequencies sound about right for that type of surveying?
Would they be of use for monitoring volcanoes?
Regards,
Chris Chapman
In a me=
ssage dated 2006/09/05, JohnJan@........ writes:
Not too good for distant earthq=
uakes, but the price is right, especially
if you live near Stanford University. These should NOT go into the
landfill!!!
John
>Subject: 8 Hz geophones, vertical and horizontal, available free to a
>good home
>Stanford University owns a large number of 8 Hz geophones, as used in
>conjunction with the Seismic Group Recorder (SGR-III) facility in
>many PASSCAL experiments from 1980 to 2001.
>We have about 200 "short" strings of 6 modified Mark Products L-10B
>vertical-component geophones (8 Hz) connected in series, with c. 1 m
>cable between each phone.
>We also own a larger number of "long" strings of 12 L-10B vertical
>phones, or of 12 horizontal phones, in each case with c. 15 m cable
>between each phone, one string per clip.
Dear Professor Klemperer,
Have you contacted anyone interested in=
archaeology? These string lengths and operating frequencies sound about rig=
ht for that type of surveying?
Would they be of use for monitoring vol=
canoes?
Regards,
Chris Chapman
Subject: Re: [IRIS] 8 Hz geophones, vertical and horizontal, available free
From: jonfr500@.........
Date: Tue, 5 Sep 2006 23:19:58 +0000
Hi
I am not home at the moment and won't be back home until after 20th Septemb=
er. But I want to know more about those 8Hz geophones. They might be useful=
for me (if shipping is avable for them) to monitor earthquakes. I know tha=
t 4.5Hz geophone does it's job without a problem.
I am only going to be able to check the email for sure tomorrow, after that=
I don't know.
Regards.
J=F3n Fr=EDmann.
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Risk of a large earthquake in California soon
From: Alexandr Yagodin midia@..............
Date: Wed, 06 Sep 2006 10:45:22 +0200
All this - is possible. The people it does not rescue.
It is necessary to use System, which is based on opening of a wave, which
earlier иŃпоОНŃСОваНи only animals.
I while do not have English translation. Clause in Russian:
http://www.inauka.ru/blogs/article59861.html
Best regards
Alexandr Yagodin
----- Original Message -----
From: "David Sarraf"
To:
Sent: Sunday, September 03, 2006 11:08 PM
Subject: Risk of a large earthquake in California soon
> Chris, JĂłn
>
> The August 21 issue of Electronic Engineering Times has a short article
about an earthquake warning system that sends alerts through via cable TV.
It is an extension of an existing network that provides alarms to hospitals,
schools, and industry. They admit that it may not provide more than a few
seconds warning in worst case scenarios but it was felt that even that
amount of time was much better than nothing at all. It would be at least
enough time to stop a train or find the best place to stand. For more info
see www.eetimes.com, search for article ID 0405734.
>
> Dave Sarraf
>
> __________________________________________________________
>
> 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: Risk of a large earthquake in California soon
From: "Rolando Benitez" rbenitez@........
Date: Wed, 6 Sep 2006 10:50:50 -0500
Alexandr,
Do you have your document written in other language like Spanish, =
French, Italian or German?
In the blog it is referenced with the title and tables in English, does =
it exist in such language?
The anticipated animal reaction to quakes is a known story among the =
post-Maya local indigenous societies around this very seismic location.
Regards,
Rolando
Fraijanes, Guatemala.
...-----Original Message-----
...From: psn-l-request@..............
...[mailto:psn-l-request@................. Behalf Of Alexandr Yagodin
...Sent: Wednesday, September 06, 2006 3:45 AM
...To: psn-l@..............
...Subject: Re: Risk of a large earthquake in California soon
...
...
...All this - is possible. The people it does not rescue.
...
...It is necessary to use System, which is based on opening of a wave, =
which
...earlier =
=D0=B8=D1=81=D0=BF=D0=B5=D0=BE=D0=BB=D1=8C=D0=B7=D0=BE=D0=B2=D0=B0=D0=BB=D0=
=B8 only animals.
...
...I while do not have English translation. Clause in Russian:
...
...http://www.inauka.ru/blogs/article59861.html
...
...Best regards
...
...Alexandr Yagodin
...
...
...
...----- Original Message -----=20
...From: "David Sarraf"
...To:
...Sent: Sunday, September 03, 2006 11:08 PM
...Subject: Risk of a large earthquake in California soon
...
...
...> Chris, J=C3=B3n
...>
...> The August 21 issue of Electronic Engineering Times has a short =
article
...about an earthquake warning system that sends alerts through via cable =
TV.
...It is an extension of an existing network that provides alarms to=20
...hospitals,
...schools, and industry. They admit that it may not provide more than a =
few
...seconds warning in worst case scenarios but it was felt that even that
...amount of time was much better than nothing at all. It would be at =
least
...enough time to stop a train or find the best place to stand. For=20
...more info
...see www.eetimes.com, search for article ID 0405734.
...>
...> Dave Sarraf
...>
...> __________________________________________________________
...>
...> 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=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: Risk of a large earthquake in California soon
From: Alexandr Yagodin midia@..............
Date: Wed, 06 Sep 2006 21:34:55 +0200
Dear Rolando!
I have made translation on the English first part of the project, but in
clause probably there are many grammatic mistakes.
http://www.seu.ru/members/earthquakes/index.html?x=9103
Now we prepare clause together with the doctor S.Đavrodiev from Bulgaria.
He makes it in English.
Best regards.
Alexandr Yagodin.
----- Original Message -----
From: "Rolando Benitez"
To:
Sent: Wednesday, September 06, 2006 5:50 PM
Subject: RE: Risk of a large earthquake in California soon
Alexandr,
Do you have your document written in other language like Spanish, French,
Italian or German?
In the blog it is referenced with the title and tables in English, does it
exist in such language?
The anticipated animal reaction to quakes is a known story among the
post-Maya local indigenous societies around this very seismic location.
Regards,
Rolando
Fraijanes, Guatemala.
...-----Original Message-----
...From: psn-l-request@..............
...[mailto:psn-l-request@................. Behalf Of Alexandr Yagodin
...Sent: Wednesday, September 06, 2006 3:45 AM
...To: psn-l@..............
...Subject: Re: Risk of a large earthquake in California soon
...
...
...All this - is possible. The people it does not rescue.
...
...It is necessary to use System, which is based on opening of a wave, which
...earlier иŃпоОНŃСОваНи only animals.
...
...I while do not have English translation. Clause in Russian:
...
...http://www.inauka.ru/blogs/article59861.html
...
...Best regards
...
...Alexandr Yagodin
...
...
...
...----- Original Message -----
...From: "David Sarraf"
...To:
...Sent: Sunday, September 03, 2006 11:08 PM
...Subject: Risk of a large earthquake in California soon
...
...
...> Chris, JĂłn
...>
...> The August 21 issue of Electronic Engineering Times has a short article
...about an earthquake warning system that sends alerts through via cable TV.
...It is an extension of an existing network that provides alarms to
...hospitals,
...schools, and industry. They admit that it may not provide more than a few
...seconds warning in worst case scenarios but it was felt that even that
...amount of time was much better than nothing at all. It would be at least
...enough time to stop a train or find the best place to stand. For
...more info
...see www.eetimes.com, search for article ID 0405734.
...>
...> Dave Sarraf
...>
...> __________________________________________________________
...>
...> 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 a large earthquake in California soon
From: "Rolando Benitez" rbenitez@........
Date: Wed, 6 Sep 2006 16:22:39 -0500
Thank you!
...-----Original Message-----
...From: psn-l-request@..............
...[mailto:psn-l-request@................. Behalf Of Alexandr Yagodin
...Sent: Wednesday, September 06, 2006 2:35 PM
...To: psn-l@..............
...Subject: Re: Risk of a large earthquake in California soon
...
...
...Dear Rolando!
...I have made translation on the English first part of the project, but =
in
...clause probably there are many grammatic mistakes.
...
...http://www.seu.ru/members/earthquakes/index.html?x=3D9103
...
...Now we prepare clause together with the doctor S.=D0=9Cavrodiev from =
Bulgaria.
...He makes it in English.
...
...Best regards.
...
...Alexandr Yagodin.
...
...
...
...
...
...----- Original Message -----=20
...From: "Rolando Benitez"
...To:
...Sent: Wednesday, September 06, 2006 5:50 PM
...Subject: RE: Risk of a large earthquake in California soon
...
...
...Alexandr,
...Do you have your document written in other language like Spanish, =
French,
...Italian or German?
...In the blog it is referenced with the title and tables in=20
...English, does it
...exist in such language?
...The anticipated animal reaction to quakes is a known story among the
...post-Maya local indigenous societies around this very seismic =
location.
...Regards,
...Rolando
...Fraijanes, Guatemala.
...
.....-----Original Message-----
.....From: psn-l-request@..............
.....[mailto:psn-l-request@................. Behalf Of Alexandr Yagodin
.....Sent: Wednesday, September 06, 2006 3:45 AM
.....To: psn-l@..............
.....Subject: Re: Risk of a large earthquake in California soon
.....
.....
.....All this - is possible. The people it does not rescue.
.....
.....It is necessary to use System, which is based on opening of a=20
...wave, which
.....earlier =
=D0=B8=D1=81=D0=BF=D0=B5=D0=BE=D0=BB=D1=8C=D0=B7=D0=BE=D0=B2=D0=B0=D0=BB=D0=
=B8 only animals.
.....
.....I while do not have English translation. Clause in Russian:
.....
.....http://www.inauka.ru/blogs/article59861.html
.....
.....Best regards
.....
.....Alexandr Yagodin
.....
.....
.....
.....----- Original Message -----=20
.....From: "David Sarraf"
.....To:
.....Sent: Sunday, September 03, 2006 11:08 PM
.....Subject: Risk of a large earthquake in California soon
.....
.....
.....> Chris, J=C3=B3n
.....>
.....> The August 21 issue of Electronic Engineering Times has a=20
...short article
.....about an earthquake warning system that sends alerts through=20
...via cable TV.
.....It is an extension of an existing network that provides alarms to
.....hospitals,
.....schools, and industry. They admit that it may not provide more=20
...than a few
.....seconds warning in worst case scenarios but it was felt that even =
that
.....amount of time was much better than nothing at all. It would be at =
least
.....enough time to stop a train or find the best place to stand. For
.....more info
.....see www.eetimes.com, search for article ID 0405734.
.....>
.....> Dave Sarraf
.....>
.....> __________________________________________________________
.....>
.....> 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=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: Three most active volcanos in Iceland are heating up
From: Jan Froom JDarwin@.............
Date: Wed, 06 Sep 2006 16:06:05 -0700
Apparently Jón wasn't all that incorrect when he said "that three most
active volcanoes in Iceland are heating up".
An article on MSNBC Scientist Identify Volcanic Trigger
today, says.... By studying
volcanic magma, or molten rock, from erupted volcanoes they have
determined that it heats itself up as it rises from deep below the
surface -- which may provide an important trigger for an eruption. "As
the magma ascends beneath the volcano prior to an eruption, it
crystallizes in response to the drop in pressure and gets hotter at the
same time,"
Geoffrey wrote:
> This is all quite interesting.
>
> However I do not understand how magma
> which has seperated from its source of
> energy deep inside the Earth can be "HEATING UP"
>
> It seems to me that from the time it begins
> its bouyant travels melting through the
> Earths Crust to reach the surface it
> will be cooling all the way.
>
> Maybe what you are saying here is that
> the magma chamber is expanding or
> something like that.
>
> I do, however, understand the meaning of
> increased activity.
>
>
> Regards;
> geoff
>
> ----- Original Message ----- From: "Jón Frímann"
> To: "PSN-Postlist"
> Sent: Thursday, August 31, 2006 12:58 PM
> Subject: Three most active volcanos in Iceland are heating up
>
>
>> Hi all
>>
>> According to Icelandic news it appeears that three most active volcanos
>> in Iceland are heating up. But that are Grimsvotn (Grimsfjall),
>> Myrdalsjokull, Hekla. Volcano named Bardarbunga is also starting to show
>> signs of incresed activite, but nothing conclusive yet. Helka has been
>> erupting every ten year since 1970, last eruption was in 2000.
>> Grimsfjall did last erupt in 2004. Myrdalsjokull last eruption was in
>> 1918. Bardarbunga did last erupt in 1903.
>>
>> When thease volcanos erupts I am problay going to see some of the
>> activie on my sensor, how much exacly is unkown to me. I am going to
>> record the eruption releated earthquakes for sure (above mag 2.8) when
>> the time comes.
>>
>> Regards.
>> --
>> Jón Frímann
>> http://www.jonfr.com
>> http://www.simnet.is/jonfr500/earthquake/
>>
>> __________________________________________________________
>>
>> 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.
>
>
>
Apparently Jón wasn't all that
incorrect when he said "that three most active volcanoes in
Iceland are heating up".
An article on MSNBC Scientist Identify
Volcanic Trigger today, says.... By
studying volcanic magma, or molten rock, from erupted volcanoes they
have determined that it heats itself up
as it rises from deep below the
surface — which may provide an important trigger for an eruption. “As
the magma ascends beneath the volcano prior to an eruption, it
crystallizes in response to the drop in pressure
and gets hotter at the
same time,”
Geoffrey wrote:
This is all quite interesting.
However I do not understand how magma
which has seperated from its source of
energy deep inside the Earth can be "HEATING UP"
It seems to me that from the time it begins
its bouyant travels melting through the
Earths Crust to reach the surface it
will be cooling all the way.
Maybe what you are saying here is that
the magma chamber is expanding or
something like that.
I do, however, understand the meaning of
increased activity.
Regards;
geoff
----- Original Message ----- From: "Jón Frímann"
<jonfr500@.........>
To: "PSN-Postlist" <PSN-L@..............>
Sent: Thursday, August 31, 2006 12:58 PM
Subject: Three most active volcanos in Iceland are heating up
Hi all
According to Icelandic news it appeears that three most active volcanos
in Iceland are heating up. But that are Grimsvotn (Grimsfjall),
Myrdalsjokull, Hekla. Volcano named Bardarbunga is also starting to
show
signs of incresed activite, but nothing conclusive yet. Helka has been
erupting every ten year since 1970, last eruption was in 2000.
Grimsfjall did last erupt in 2004. Myrdalsjokull last eruption was in
1918. Bardarbunga did last erupt in 1903.
When thease volcanos erupts I am problay going to see some of the
activie on my sensor, how much exacly is unkown to me. I am going to
record the eruption releated earthquakes for sure (above mag 2.8) when
the time comes.
Regards.
--
Jón Frímann
http://www.jonfr.com
http://www.simnet.is/jonfr500/earthquake/
__________________________________________________________
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.
Subject: Re: Risk of a large earthquake in California soon
From: Alexandr Yagodin midia@..............
Date: Thu, 07 Sep 2006 09:59:04 +0200
http://www.inauka.ru/blogs/article59860.html
Measuring this wave it is possible precisely to predict earthquakes behind
many time up to their beginning.
The examination of the Russian academy of sciences has approved this work.
Now I begin work with firm - financier, therefore I can not inform a detail.
If there is a desire and financial opportunities to join work, inform.
Then we shall discuss it with the one who finances me.
Best regards.
Alexandr Yagodin.
----- Original Message -----
From: "Rolando Benitez"
To:
Sent: Wednesday, September 06, 2006 11:22 PM
Subject: RE: Risk of a large earthquake in California soon
Thank you!
...-----Original Message-----
...From: psn-l-request@..............
...[mailto:psn-l-request@................. Behalf Of Alexandr Yagodin
...Sent: Wednesday, September 06, 2006 2:35 PM
...To: psn-l@..............
...Subject: Re: Risk of a large earthquake in California soon
...
...
...Dear Rolando!
...I have made translation on the English first part of the project, but in
...clause probably there are many grammatic mistakes.
...
...http://www.seu.ru/members/earthquakes/index.html?x=9103
...
...Now we prepare clause together with the doctor S.Đavrodiev from Bulgaria.
...He makes it in English.
...
...Best regards.
...
...Alexandr Yagodin.
...
...
...
...
...
...----- Original Message -----
...From: "Rolando Benitez"
...To:
...Sent: Wednesday, September 06, 2006 5:50 PM
...Subject: RE: Risk of a large earthquake in California soon
...
...
...Alexandr,
...Do you have your document written in other language like Spanish, French,
...Italian or German?
...In the blog it is referenced with the title and tables in
...English, does it
...exist in such language?
...The anticipated animal reaction to quakes is a known story among the
...post-Maya local indigenous societies around this very seismic location.
...Regards,
...Rolando
...Fraijanes, Guatemala.
...
.....-----Original Message-----
.....From: psn-l-request@..............
.....[mailto:psn-l-request@................. Behalf Of Alexandr Yagodin
.....Sent: Wednesday, September 06, 2006 3:45 AM
.....To: psn-l@..............
.....Subject: Re: Risk of a large earthquake in California soon
.....
.....
.....All this - is possible. The people it does not rescue.
.....
.....It is necessary to use System, which is based on opening of a
...wave, which
.....earlier иŃпоОНŃСОваНи only animals.
.....
.....I while do not have English translation. Clause in Russian:
.....
.....http://www.inauka.ru/blogs/article59861.html
.....
.....Best regards
.....
.....Alexandr Yagodin
.....
.....
.....
.....----- Original Message -----
.....From: "David Sarraf"
.....To:
.....Sent: Sunday, September 03, 2006 11:08 PM
.....Subject: Risk of a large earthquake in California soon
.....
.....
.....> Chris, JĂłn
.....>
.....> The August 21 issue of Electronic Engineering Times has a
...short article
.....about an earthquake warning system that sends alerts through
...via cable TV.
.....It is an extension of an existing network that provides alarms to
.....hospitals,
.....schools, and industry. They admit that it may not provide more
...than a few
.....seconds warning in worst case scenarios but it was felt that even that
.....amount of time was much better than nothing at all. It would be at least
.....enough time to stop a train or find the best place to stand. For
.....more info
.....see www.eetimes.com, search for article ID 0405734.
.....>
.....> Dave Sarraf
.....>
.....> __________________________________________________________
.....>
.....> 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)
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: P2P Hard Disk System Warns of Tsunamis
From: Mark Robinson mark.robinson@...............
Date: Fri, 08 Sep 2006 09:31:50 +1200
PC hard disk system warns of Tsunamis
By John Blau, IDG News Service, 09/07/06
Governments seeking inexpensive technology to warn of tsunamis could be
interested in a free software application that monitors vibrations in the hard
disks of computers in an attempt to detect the undersea earthquakes that cause
tsunamis.
The Tsunami Harddisk Detector is the brainchild of Michael Stadler, who
demonstrated the prototype system earlier this week at the Ars Electronica
exhibition in Linz, Austria.
....
http://www.networkworld.com/news/2006/090706-pc-hard-disk-system-warns.html
http://science.slashdot.org/science/06/09/07/1922214.shtml
--
08 Sep 1893 Women's Suffrage is passed by the New Zealand legislature in Coucil
by 20 votes to 18.
08 Sep 1966 The first episode of Ster Trek is televised.
08 Sep 1991 Macedonia becomes the third Yugoslav republic to declare itself
independant.
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: P2P Hard Disk System Warns of Tsunamis
From: ChrisAtUpw@.......
Date: Thu, 7 Sep 2006 21:59:52 EDT
In a message dated 2006/09/07, mark.robinson@............... writes:
> PC hard disk system warns of Tsunamis
> By John Blau, IDG News Service, 09/07/06
>
> Governments seeking inexpensive technology to warn of tsunamis could be
> interested in a free software application that monitors vibrations in the
> hard
> disks of computers in an attempt to detect the undersea earthquakes that
> cause
> tsunamis.
>
> The Tsunami Harddisk Detector is the brainchild of Michael Stadler, who
> demonstrated the prototype system earlier this week at the Ars Electronica
> exhibition in Linz, Austria.
> http://www.networkworld.com/news/2006/090706-pc-hard-disk-system-warns.html
> http://science.slashdot.org/science/06/09/07/1922214.shtml
Hi there,
Before anyone spends money, the hard disks have a MEMS accelerometer
in them. It has a fairly high noise and a short period. This is not even
suitable for ordinary seismic detectors. For tsunami detection you need low noise
and about 300 sec period. This account is a 'late entry' - the possible seismic
application was noted and dismissed several years ago.
Regards,
Chris Chapman
In a me=
ssage dated 2006/09/07, mark.robinson@............... writes:
PC hard disk system warns of Ts=
unamis
By John Blau, IDG News Service, 09/07/06
Governments seeking inexpensive technology to warn of tsunamis could be
interested in a free software application that monitors vibrations in the ha=
rd
disks of computers in an attempt to detect the undersea earthquakes that cau=
se
tsunamis.
The Tsunami Harddisk Detector is the brainchild of Michael Stadler, who
demonstrated the prototype system earlier this week at the Ars Electronica <=
BR>
exhibition in Linz, Austria.
http://www.networkworld.com/news/2006/090706-pc-hard-disk-system-warns.html<=
BR>
http://science.slashdot.org/science/06/09/07/1922214.shtml
Hi there,
Before anyone spends money, the hard di=
sks have a MEMS accelerometer in them. It has a fairly high noise and a shor=
t period. This is not even suitable for ordinary seismic detectors. For tsun=
ami detection you need low noise and about 300 sec period. This account is a=
'late entry' - the possible seismic application was noted and dismiss=
ed several years ago.
Regards,
Chris Chapman
Subject: Earthquakes in a unusal location
From: jonfr500@.........
Date: Fri, 8 Sep 2006 18:05:04 +0000
Hi all
I am not home at the moment, so I can't give full detail. But there where t=
oday a series of earthquakes in a area that hasn't had earthquakes for at l=
east 11+ years and is not considered an active area, both in volcano activt=
ie and earthquakes. The biggest earthquake was 3.4M and was located 60 - 70=
NW of Hvammstangi, where my station is. This appears to have started with =
a earthquake that was M3.0, there where several small earthquakes following=
this, the smallest one detected by IMO was M1.9. I do not know at this mom=
ent how many earthquakes where detected in total by my system, but I can re=
cord earthquakes down to M1.4 at least at that range, problay a bit lower (=
my guess is M1.0 - M1.2).
For more info on this check IMO website here, http://hraun.vedur.is/ja/engl=
ishweb/index.html
The earthquakes can also be seen on my tremor plots, here, http://www.simne=
t.is/jonfr500/earthquake/tremoren.htm
The green star marks the location of the earthquakes. I am going to send tr=
aces of the largest earthquakes to the PSN event list when I get home, some=
times after 20th of September.
Regards.
J=F3n Fr=EDmann.
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: autolocator
From: Angel sismos@..............
Date: Sat, 9 Sep 2006 11:15:51 +0000
Hi Everyone,
I have had an auto-locator working for some time. I just did some
upgrades using google maps. I post the last one to this page
http://www.volcanbaru.com/OSOP/lastquake.html
I classify the locations into 5 categories
excellent
very good
good
ok
only a fool would trust this
I can send an auto-email to anyone that would like to then. They get generated
with a a minute or two of the event. The email is tiny and only has
the a url that points to the event.
If any would like to receive then for just drop me a note. Getting
off is just as easy.
It would be very easy to join all of the systems using Larry's WinSDR
serial card, accurate timing and a full-time internet connection into a
fast autolocating system that would do much the same thing.
Angel
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Risk of a large earthquake in California soon
From: Alexandr Yagodin midia@..............
Date: Sun, 10 Sep 2006 18:37:58 +0200
2006-09-10 14:56:08.9 26.19 N 86.80 W 40 mb 5.8 GULF OF
MEXICO
I assume, that through 24 - 25 hours (from 2006-09-10 14:56:08.9 ) can be
earthquake in California.
( Unfortunately, I do not have gauges in America...)
Best regards
Alexandr Yagodin
----- Original Message -----
From: "Rolando Benitez"
To:
Sent: Wednesday, September 06, 2006 11:22 PM
Subject: RE: Risk of a large earthquake in California soon
Thank you!
...-----Original Message-----
...From: psn-l-request@..............
...[mailto:psn-l-request@................. Behalf Of Alexandr Yagodin
...Sent: Wednesday, September 06, 2006 2:35 PM
...To: psn-l@..............
...Subject: Re: Risk of a large earthquake in California soon
...
...
...Dear Rolando!
...I have made translation on the English first part of the project, but in
...clause probably there are many grammatic mistakes.
...
...http://www.seu.ru/members/earthquakes/index.html?x=9103
...
...Now we prepare clause together with the doctor S.Đavrodiev from Bulgaria.
...He makes it in English.
...
...Best regards.
...
...Alexandr Yagodin.
...
...
...
...
...
...----- Original Message -----
...From: "Rolando Benitez"
...To:
...Sent: Wednesday, September 06, 2006 5:50 PM
...Subject: RE: Risk of a large earthquake in California soon
...
...
...Alexandr,
...Do you have your document written in other language like Spanish, French,
...Italian or German?
...In the blog it is referenced with the title and tables in
...English, does it
...exist in such language?
...The anticipated animal reaction to quakes is a known story among the
...post-Maya local indigenous societies around this very seismic location.
...Regards,
...Rolando
...Fraijanes, Guatemala.
...
.....-----Original Message-----
.....From: psn-l-request@..............
.....[mailto:psn-l-request@................. Behalf Of Alexandr Yagodin
.....Sent: Wednesday, September 06, 2006 3:45 AM
.....To: psn-l@..............
.....Subject: Re: Risk of a large earthquake in California soon
.....
.....
.....All this - is possible. The people it does not rescue.
.....
.....It is necessary to use System, which is based on opening of a
...wave, which
.....earlier иŃпоОНŃСОваНи only animals.
.....
.....I while do not have English translation. Clause in Russian:
.....
.....http://www.inauka.ru/blogs/article59861.html
.....
.....Best regards
.....
.....Alexandr Yagodin
.....
.....
.....
.....----- Original Message -----
.....From: "David Sarraf"
.....To:
.....Sent: Sunday, September 03, 2006 11:08 PM
.....Subject: Risk of a large earthquake in California soon
.....
.....
.....> Chris, JĂłn
.....>
.....> The August 21 issue of Electronic Engineering Times has a
...short article
.....about an earthquake warning system that sends alerts through
...via cable TV.
.....It is an extension of an existing network that provides alarms to
.....hospitals,
.....schools, and industry. They admit that it may not provide more
...than a few
.....seconds warning in worst case scenarios but it was felt that even that
.....amount of time was much better than nothing at all. It would be at least
.....enough time to stop a train or find the best place to stand. For
.....more info
.....see www.eetimes.com, search for article ID 0405734.
.....>
.....> Dave Sarraf
.....>
.....> __________________________________________________________
.....>
.....> 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.
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Subject: M 6.0 Event Gulf Of Mexico
From: "Bob Hancock" carpediem1@.........
Date: Mon, 11 Sep 2006 11:58:47 -0700
The recent M 6.0 event in the Gulf of Mexico has some unique features.
* 1. The event was not located near any plate boundary. It is
about 490 nm (907.5 km) north of the boundary with the Caribbean plate and
that boundary is described as a strike-slip boundary (like the San Andreas),
and not a subduction zone.
* 2. It has been over 24 hours since the event and there have
been no aftershocks.
* 3. There are significant differences in the calculated depth
of the event. According to the moment tensor solutions, the USGS plots the
depth at 4 km, and Harvard plots the depth at 31.7 km.
Here is a link to an article from a petroleum geologist about tectonics in
the gulf. I don't know how valid the comments are, but they are
interesting.
http://www.aapg.org/explorer/2002/11nov/rift_zone.cfm
Bob Hancock
Three Points, AZ
The
recent M 6.0 event in the Gulf of =
Mexico has
some unique features.
Ø =
1. &n=
bsp; The
event was not located near any plate boundary. It is about 490 nm =
(907.5
km) north of the boundary with the Caribbean plate and that boundary is
described as a strike-slip boundary (like the San Andreas), and not a
subduction zone.
Ø =
2. &n=
bsp; It
has been over 24 hours since the event and there have been no =
aftershocks.
Ø =
3. &n=
bsp; There
are significant differences in the calculated depth of the event.
According to the moment tensor solutions, the USGS plots the depth at 4 =
km, and
Harvard plots the depth at 31.7 km.
Here
is a link to an article from a petroleum geologist about tectonics in =
the
gulf. I don’t know how valid the comments are, but they are
interesting.
&nbs=
p; http://www=
..aapg.org/explorer/2002/11nov/rift_zone.cfm<=
/p>
Bob
Hancock
Three
Points, AZ
Subject: Re: M 6.0 Event Gulf Of Mexico
From: "Thomas Dick" dickthomas01@.............
Date: Mon, 11 Sep 2006 14:53:28 -0500
1. there have been NO 5+ earthquakes here in southern Indiana (Evansville,
IN is my locale) this year
2. I am sure there is an explanation but the arrival time for P this locale
(800 miles) was .11 seconds earlier than predicted (this is rare for P to be
early) -- this is my calculations but can be seen on U of Southern Indiana
as well
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: RE: M 6.0 Event Gulf Of Mexico
From: "Bob Hancock" carpediem1@.........
Date: Mon, 11 Sep 2006 12:59:19 -0700
Southern Indiana is also very close to the new Madrid zone. Both the Gulf
of Mexico event and the New Madrid events were intraplate events....
-----Original Message-----
From: psn-l-request@.............. [mailto:psn-l-request@............... On
Behalf Of Thomas Dick
Sent: Monday, September 11, 2006 12:53
To: psn-l@..............
Cc: David Dick
Subject: Re: M 6.0 Event Gulf Of Mexico
1. there have been NO 5+ earthquakes here in southern Indiana (Evansville,
IN is my locale) this year
2. I am sure there is an explanation but the arrival time for P this locale
(800 miles) was .11 seconds earlier than predicted (this is rare for P to be
early) -- this is my calculations but can be seen on U of Southern Indiana
as well
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: M 6.0 Event Gulf Of Mexico
From: "Thomas Dick" dickthomas01@.............
Date: Mon, 11 Sep 2006 15:42:47 -0500
> Southern Indiana is also very close to the new Madrid zone. Both the Gulf
> of Mexico event and the New Madrid events were intraplate events...
Yes, and since the beginning of this month there have been seven minor
quakes (1.5 to 3.3) in that immediate area (New Madrid). The number isn't
that high but this group seemed to be of excellant quality which is usual.
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Long-period vs short-period instruments
From: John or Jan Lahr JohnJan@........
Date: Tue, 12 Sep 2006 07:55:06 -0700
A few times the question has come up about which events can be seen
on short period
versus a long period instruments.
I've set up a page with images of the broad-band station COR, which
is run by the USGS
and Oregon State University: http://www.jclahr.com/science/psn/cor/index.html
Clicking on this image toggles between short-period- and
long-period-filtered versions.
There is a lot of cultural noise around Corvallis, so often the
short-period record shows
nothing while the long-period record clearly picks up a distant earthquake.
Cheers,
John
#################################/ John C. Lahr
################################/ Emeritus Seismologist
###############################/ U.S. Geological Survey
==========================/ Central Region Geologic Hazards Team
#############################//#################################
############################//##################################
PO Box 548 /###################################
Corvallis, Oregon 97339 /===============================
Phone: (541) 758-2699 /####################################
Cell: (541) 740-4844 /#####################################
Fax: (928) 569-0113 /######################################
jjpub@........ /#######################################
http://jclahr.com/science/
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Long-period vs short-period instruments
From: ChrisAtUpw@.......
Date: Tue, 12 Sep 2006 11:37:15 EDT
In a message dated 2006/09/12, JohnJan@........ writes:
> A few times the question has come up about which events can be seen
> on short period versus a long period instruments.
>
> I've set up a page with images of the broad-band station COR, which
> is run by the USGS
> and Oregon State University:
> http://www.jclahr.com/science/psn/cor/index.html
>
> Clicking on this image toggles between short-period- and
> long-period-filtered versions.
Hi John,
Not many of us have instruments which go to 1000 sec. Can you show us
what the 10 to 40 sec band looks like in comparison, please?
Regards,
Chris Chapman
In a me=
ssage dated 2006/09/12, JohnJan@........ writes:
A few times the question has co=
me up about which events can be seen
on short period versus a long period instruments.
I've set up a page with images of the broad-band station COR, which
is run by the USGS
and Oregon State University: http://www.jclahr.com/science/psn/cor/ind=
ex.html
Clicking on this image toggles between short-period- and
long-period-filtered versions.
Hi John,
Not many of us have instruments which g=
o to 1000 sec. Can you show us what the 10 to 40 sec band looks like in comp=
arison, please?
Regards,
Chris Chapman
Subject: RE: Long-period vs short-period instruments
From: "Jack Ivey" ivey@..........
Date: Tue, 12 Sep 2006 13:27:36 -0400
Most of the energy in the long period looks to be in the <45 second
range already.
=20
Jack
=20
________________________________
From: psn-l-request@.............. [mailto:psn-l-request@...............
On Behalf Of ChrisAtUpw@.......
Sent: Tuesday, September 12, 2006 11:37 AM
To: psn-l@..............
Subject: Re: Long-period vs short-period instruments
=20
In a message dated 2006/09/12, JohnJan@........ writes:
A few times the question has come up about which events can be seen=20
on short period versus a long period instruments.
I've set up a page with images of the broad-band station COR, which=20
is run by the USGS
and Oregon State University:
http://www.jclahr.com/science/psn/cor/index.html
Clicking on this image toggles between short-period- and=20
long-period-filtered versions.
Hi John,
Not many of us have instruments which go to 1000 sec. Can you
show us what the 10 to 40 sec band looks like in comparison, please?
Regards,
Chris Chapman
Most of the energy in the long =
period looks
to be in the <45 second range already.
Jack
From:
psn-l-request@.............. [mailto:psn-l-request@............... =
On Behalf Of ChrisAtUpw@.......
Sent: Tuesday, September =
12, 2006
11:37 AM
To: psn-l@..............
Subject: Re: Long-period =
vs
short-period instruments
In a message dated 2006/09/12, JohnJan@........ =
writes:
A few times the question has come up about which =
events can
be seen
on short period versus a long period instruments.
I've set up a page with images of the broad-band station COR, which
is run by the USGS
and Oregon
State University: =
http://www.jclahr.com/science/psn/cor/index.html
Clicking on this image toggles between short-period- and
long-period-filtered versions.
Hi John,
Not many of us have instruments =
which go
to 1000 sec. Can you show us what the 10 to 40 sec band looks like in
comparison, please?
Regards,
Chris Chapman
Subject: Re: M 6.0 Event Gulf Of Mexico
From: jonfr500@.........
Date: Tue, 12 Sep 2006 18:15:09 +0000
Hi
The location of the earthquake in a gulf of Mexico is intresting. There hav=
e been other earthquakes happening on the planet that where in unusual loca=
tions (see my earlyer email for details). But this one is the strongest one=
I know about at the moment. Emsc-csem puts this earthquake at 2km depth, m=
ore details here, http://www.emsc-csem.org/index.php?page=3Dcurrent&sub=3Dd=
etail&id=3D34030
Regards.
J=F3n Fr=EDmann.
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: M 6.0 Event Gulf Of Mexico
From: Ben Bradley benbradley@...............
Date: Tue, 12 Sep 2006 14:59:48 -0400
jonfr500@......... wrote:
> Hi
>
> The location of the earthquake in a gulf of Mexico is intresting.
> There have been other earthquakes happening on the planet that where
> in unusual locations (see my earlyer email for details). But this one
> is the strongest one I know about at the moment. Emsc-csem puts this
> earthquake at 2km depth, more details here,
> http://www.emsc-csem.org/index.php?page=current&sub=detail&id=34030
Firstly, let me "qualify" myself: I have at best only a layman's
knowledge of geology, and this question is an attempt to learn something.
I noticed this news report several days ago concerning a large oil
reserve found in the Gulf of Mexico. Quoting a pertinent sentence:
"...the announcement of a test well that sustained a flow rate of more
than 6,000 barrels a day is a boon to Western oil companies." Could this
have any possible relation to the gulf earthquake? Has there ever been
a correlation found between oil drilling/pumping and earthquakes?
http://www.cnn.com/2006/TECH/science/09/05/oil.discovery.ap/index.html
>
> Regards. Jón Frímann.
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: M 6.0 Event Gulf Of Mexico
From: "wildboar" wildboar@..............
Date: Tue, 12 Sep 2006 14:59:49 -0400
would you please send me your earlier email? thanks. be interested if there
is a linking thread between these unusual places.
patrick
----- Original Message -----
From:
To:
Sent: Tuesday, September 12, 2006 2:15 PM
Subject: Re: M 6.0 Event Gulf Of Mexico
Hi
The location of the earthquake in a gulf of Mexico is intresting. There have
been other earthquakes happening on the planet that where in unusual
locations (see my earlyer email for details). But this one is the strongest
one I know about at the moment. Emsc-csem puts this earthquake at 2km depth,
more details here,
http://www.emsc-csem.org/index.php?page=current&sub=detail&id=34030
Regards.
Jón Frímann.
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Long-period vs short-period instruments
From: John or Jan Lahr JohnJan@........
Date: Tue, 12 Sep 2006 12:12:59 -0700
Hi Chris,
I'm just displaying images that are generated at the USGS Albuquerque
Seismic Lab
(ASL). The 10 to 40 s band would be an interesting comparison, but I
don't have the raw data
to generate such a plot. I the data is available from
ASL: http://www.liss.org/software/connect.htm
so someone with the right filtering software could generate such a plot.
Cheers,
John
At 08:37 AM 9/12/2006, you wrote:
>In a message dated 2006/09/12, JohnJan@........ writes:
>
>>A few times the question has come up about which events can be seen
>>on short period versus a long period instruments.
>>
>>I've set up a page with images of the broad-band station COR, which
>>is run by the USGS
>>and Oregon State
>>University: http://www.jclahr.com/science/psn/cor/index.html
>>
>>Clicking on this image toggles between short-period- and
>>long-period-filtered versions.
>
>
>Hi John,
>
> Not many of us have instruments which go to 1000 sec. Can
> you show us what the 10 to 40 sec band looks like in comparison, please?
>
> Regards,
>
> Chris Chapman
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: RE: Long-period vs short-period instruments
From: "Bob Hancock" carpediem1@.........
Date: Tue, 12 Sep 2006 12:34:14 -0700
Chris -
IRIS has published software suitable for a PC that allows you to download
data from the IU and other networks. The program is written in JAVA. And
very useable although there is a learning curve for proficiency. The program
is called VASE, and the link for the program is
http://dmc.iris.washington.edu/manuals/
Another source for IRIS data is Wilber II at the following link
http://www.iris.edu/cgi-bin/wilberII_page1.pl
You can download files in SAC binary format and once downloaded you can
resave as PSN Type 4 files and filter to your heart's content.
Bob Hancock
Three Points, AZ
-----Original Message-----
From: psn-l-request@.............. [mailto:psn-l-request@............... On
Behalf Of John or Jan Lahr
Sent: Tuesday, September 12, 2006 12:13
To: psn-l@..............
Subject: Re: Long-period vs short-period instruments
Hi Chris,
I'm just displaying images that are generated at the USGS Albuquerque
Seismic Lab
(ASL). The 10 to 40 s band would be an interesting comparison, but I
don't have the raw data
to generate such a plot. I the data is available from
ASL: http://www.liss.org/software/connect.htm
so someone with the right filtering software could generate such a plot.
Cheers,
John
At 08:37 AM 9/12/2006, you wrote:
>In a message dated 2006/09/12, JohnJan@........ writes:
>
>>A few times the question has come up about which events can be seen
>>on short period versus a long period instruments.
>>
>>I've set up a page with images of the broad-band station COR, which
>>is run by the USGS
>>and Oregon State
>>University: http://www.jclahr.com/science/psn/cor/index.html
>>
>>Clicking on this image toggles between short-period- and
>>long-period-filtered versions.
>
>
>Hi John,
>
> Not many of us have instruments which go to 1000 sec. Can
> you show us what the 10 to 40 sec band looks like in comparison, please?
>
> Regards,
>
> Chris Chapman
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: M 6.0 Event Gulf Of Mexico
From: John Popelish jpopelish@........
Date: Tue, 12 Sep 2006 17:15:57 -0400
jonfr500@......... wrote:
> Hi
>
> The location of the earthquake in a gulf of Mexico is intresting.
> There have been other earthquakes happening on the planet
> that where in unusual locations
> (see my earlyer email for details).
> But this one is the strongest one I know about at the moment.
> Emsc-csem puts this earthquake at 2km depth, more details here,
> http://www.emsc-csem.org/index.php?page=current&sub=detail&id=34030
Has anyone heard a hypothesis that this is the kind of earthquake you
might expect when you pump millions of gallons of oil out of from
under the surface?
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: M 6.0 Event Gulf Of Mexico
From: jonfr500@.........
Date: Tue, 12 Sep 2006 21:15:16 +0000
> would you please send me your earlier email? thanks. be interested if th=
ere=20
> is a linking thread between these unusual places.
> patrick
Hi
I can do that after 20th of September (sorry for that), I am not home at th=
e moment.
Regards.
J=F3n Fr=EDmann.
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: RE: M 6.0 Event Gulf Of Mexico
From: "Bob Hancock" carpediem1@.........
Date: Tue, 12 Sep 2006 15:01:48 -0700
This was an intraplate event. There is no documented plate boundary nearby.
According to a seismologist at the University of Arizona that I talked to,
the North American plate is slowly moving south against the Caribbean plate
in this area; however, the initiating force has not been defined. Was there
an ancient paleo-plate boundary, or some type of pre-existing fracture zone
has not been clarified.
The moment tensor solution showed a thrust event from both the USGS and
Harvard with minor differences. This would appear to be consistent with
some type of compressive force, but there does not appear to be much
information on how this force came to be.
Here in Arizona, we have large areas of subsidence from ground water removal
so it's not improbable that there may be a relationship with the oil/gas
removal. The Arizona Geological Survey (http://www.azgs.state.az.us/) has
documented this on their web site under Earth Fissures. The fissures all
occur in the basin and range portion of the state.
Several years ago, water was pumped into oil well shafts in Colorado to get
more oil out and the water also induced many, many small earthquakes. They
subsequently stopped that practice.
Bob Hancock
-----Original Message-----
From: psn-l-request@.............. [mailto:psn-l-request@............... On
Behalf Of John Popelish
Sent: Tuesday, September 12, 2006 14:16
To: psn-l@..............
Subject: Re: M 6.0 Event Gulf Of Mexico
jonfr500@......... wrote:
> Hi
>
> The location of the earthquake in a gulf of Mexico is intresting.
> There have been other earthquakes happening on the planet
> that where in unusual locations
> (see my earlyer email for details).
> But this one is the strongest one I know about at the moment.
> Emsc-csem puts this earthquake at 2km depth, more details here,
> http://www.emsc-csem.org/index.php?page=current&sub=detail&id=34030
Has anyone heard a hypothesis that this is the kind of earthquake you
might expect when you pump millions of gallons of oil out of from
under the surface?
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: M 6.0 Event Gulf Of Mexico
From: "Thomas Dick" dickthomas01@.............
Date: Tue, 12 Sep 2006 17:53:40 -0500
> Has anyone heard a hypothesis that this is the kind of earthquake you
> might expect when you pump millions of gallons of oil out of from under
> the surface?
They haven't started pumping oil yet -- or like the earthquakes in the
Colorado area caused by pumping water back into the ground.
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: M 6.0 Event Gulf Of Mexico
From: "wildboar" wildboar@..............
Date: Wed, 13 Sep 2006 09:45:35 -0400
I'm from Florida, and your question below is exactly mine...anyone with
information on this?
Thanks,
Patrick
----- Original Message -----
From: "Ben Bradley"
To:
Sent: Tuesday, September 12, 2006 2:59 PM
Subject: Re: M 6.0 Event Gulf Of Mexico
> jonfr500@......... wrote:
>> Hi
>>
>> The location of the earthquake in a gulf of Mexico is intresting.
>> There have been other earthquakes happening on the planet that where
>> in unusual locations (see my earlyer email for details). But this one
>> is the strongest one I know about at the moment. Emsc-csem puts this
>> earthquake at 2km depth, more details here,
>> http://www.emsc-csem.org/index.php?page=current&sub=detail&id=34030
>
> Firstly, let me "qualify" myself: I have at best only a layman's
> knowledge of geology, and this question is an attempt to learn something.
>
> I noticed this news report several days ago concerning a large oil
> reserve found in the Gulf of Mexico. Quoting a pertinent sentence: "...the
> announcement of a test well that sustained a flow rate of more than 6,000
> barrels a day is a boon to Western oil companies." Could this have any
> possible relation to the gulf earthquake? Has there ever been a
> correlation found between oil drilling/pumping and earthquakes?
>
> http://www.cnn.com/2006/TECH/science/09/05/oil.discovery.ap/index.html
>
>>
>> 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)
Subject: Natural Microseismic Noise
From: "Geoffrey" gmvoeth@...........
Date: Sat, 16 Sep 2006 12:41:13 -0700
FYI,
I have noticed since early this morning the appearance
of seizable microseismic noise that seems related
to the weather disturbance in or near the Gulf Of California.
This similar thing has happened several
times before over the last 10 years or so.
Just thought I would comment on this.
This station is located in Arizona at GVA.
I am relatively sure that this type of
noise will appear each time a major storm
hits the Gulf Of California.
If I am wrong, please send me a comment.
Regards;
geoff
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Natural Microseismic Noise
From: ChrisAtUpw@.......
Date: Sun, 17 Sep 2006 02:26:10 EDT
In a message dated 2006/09/16, gmvoeth@........... writes:
> Subj:Natural Microseismic Noise
>
> I have noticed since early this morning the appearance of seizable
> microseismic noise that seems related to the weather disturbance in or near the Gulf
> Of California.
> This similar thing has happened several times before over the last 10 years
> or so.
> Just thought I would comment on this. This station is located in Arizona at
> GVA.
> I am relatively sure that this type of noise will appear each time a major
> storm
> hits the Gulf Of California.
> If I am wrong, please send me a comment.
> Regards;
> geoff
Hi Geoff,
Storms and frontal weather systems, particularly cold fronts, increase
the seismic background noise, often quiite considerably. It may tend to be
more obvious on longer period instruments like 30 sec Lehmans. You can also get
very significant wind noise, not only by the direct response of nearby trees
and buildings, but also due to mountain wave systems, some of which 'travel'
rather than staying nearly still. You may also be able to see the 'clear air
turbulence' which effects aircraft. If you have a conical mountain directly
upwind, you may see von Karman 'shedding vortices' as the air flow oscillates
around the mountain. Associated clouds can sometimes be seen on satellite photos.
These signals have tended to be rejected as 'just noise' by
seismologists, but may be worthy of study in their own right. The Pacific Coast
microseisms may vary in period quite a bit, as may the microseisms associated with
hurricanes on the east coast. You may get more than one generating centre and the
oscillations may show 'beat frequency interference'.
Regards,
Chris Chapman
In a me=
ssage dated 2006/09/16, gmvoeth@........... writes:
Subj:Natural Microseismic No=
ise
I have noticed since early this morning the appearance of seizable microseis=
mic noise that seems related to the weather disturbance in or near the Gulf=20=
Of California.
This similar thing has happened several times before over the last 10 years=20=
or so.
Just thought I would comment on this. This station is located in Arizona at=20=
GVA.
I am relatively sure that this type of noise will appear each time a major s=
torm
hits the Gulf Of California.
If I am wrong, please send me a comment.
Regards;
geoff
Hi Geoff,
Storms and frontal weather systems, par=
ticularly cold fronts, increase the seismic background noise, often quiite c=
onsiderably. It may tend to be more obvious on longer period instruments lik=
e 30 sec Lehmans. You can also get very significant wind noise, not only by=20=
the direct response of nearby trees and buildings, but also due to mountain=20=
wave systems, some of which 'travel' rather than staying nearly still. You m=
ay also be able to see the 'clear air turbulence' which effects aircraft. If=
you have a conical mountain directly upwind, you may see von Karman 'sheddi=
ng vortices' as the air flow oscillates around the mountain. Associated clou=
ds can sometimes be seen on satellite photos.
These signals have tended to be rejecte=
d as 'just noise' by seismologists, but may be worthy of study in their own=20=
right. The Pacific Coast microseisms may vary in period quite a bit, as may=20=
the microseisms associated with hurricanes on the east coast. You may get mo=
re than one generating centre and the oscillations may show 'beat frequency=20=
interference'.
Regards,
Chris Chapman
Subject: Re: Natural Microseismic Noise
From: "Geoffrey" gmvoeth@...........
Date: Sun, 17 Sep 2006 01:13:53 -0700
Thanks for your response Chris.
I understand there are industrial flow meters
relating to "von Karman 'shedding vortices' "
The higher the velocity of the flow the higher frequency caused by the vortices.
There are both obsticals and sensors located inline in the pipe.
This is used for flow control in like milk flow in a cheese processing plant.
Possibly you can tell the wind speeds aloft by
observing those indications around the mountains.
I have relatively small mountains close to here
but about 50 miles or so away is what is
called the Mogollon Rim..."Muggyon Rim" which i think
is a very high scarp relating to the Colorado Plateau.
I have never thought of it before but possibly this could be
a closer source for microseimic noises.
Regards,
geoff
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: RE: Natural Microseismic Noise
From: "Bob Hancock" carpediem1@.........
Date: Sun, 17 Sep 2006 07:28:36 -0700
Chris & Geoff -
I also picked up the microseisms yesterday, and they had a rhythmic or
cyclic appearance, with a time of about 1 minute between peaks in amplitude.
The frequency of the oscillations was between, 0.19 hz, and 0.24 hz.
I correlated yesterdays' microseisms with the winds in the area of the
Mogollon Rim. Flagstaff, AZ airport (KFLG), about 24 km north of the rim
had winds up to 20 knots at the time, but that is not uncommon for that
area. The area is flat terrain, populated with many high pine trees with a
dormant volcano on the north side of town. You can see the microseism
locally, but they do not transmit for great distances.
I also correlated the winds at Winslow, AZ airport (KINW) further east, and
about 80 km from the rim. This is high desert, flat terrain basically void
of trees and most everything else. The winds were less. The winds at Mesa,
AZ, (KFFZ), near where Geoff lives were also under 10 knots.
The microseisms were rhythmic, similar to ocean waves I have previously
observed while living in New Jersey on the East Coast of the US. At the
time of the microseisms, Hurricane Lane was in the Gulf of Baja traveling
northwest. The hurricane has subsequently moved more over land (Mexico) and
the microseisms have subsided.
One other thought - I have observed significant differences in the signature
of wind noise and wave noise. The ocean wave noise I have observed has
always been more cyclic or rhythmic where it increases and decreases in
intensity over a period of time. However, the wind noise I have observed
has always been more local in nature, and gives a more or less constant
increase in background noise without the cyclic/rhythmic increases and
decreases.
There is a strong possibility these microseisms were related to Hurricane
Lane making landfall below the tip of the Gulf of Baja.
When east coast hurricanes make land fall, they are easily observable here
in the Arizona desert.
You can check world wide ocean wave activity from this US Navy web site.
https://www.fnmoc.navy.mil/PUBLIC/WAM/all_glbl.html
You can also track hurricanes and typhoons at this web site.
http://www.nhc.noaa.gov/
You can also download a very nice conversion program for all types of
calculations at the following web site.
http://joshmadison.net/software/convert/
Bob Hancock
Three Points, AZ
-----Original Message-----
From: psn-l-request@.............. [mailto:psn-l-request@............... On
Behalf Of Geoffrey
Sent: Sunday, September 17, 2006 01:14
To: psn-l@..............
Subject: Re: Natural Microseismic Noise
Thanks for your response Chris.
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Metods for Improving SNR for events ??
From: "Jerry Payton" gpayton880@.......
Date: Sun, 17 Sep 2006 10:00:03 -0500
Is there a way or ways to improve the SNR (signal to noise ratio) of an
incoming event?
I realize that if the incoming rays are not strong enough, they will not
overcome the ambient noise of the system.
I would further assume that lowering the ambient noise is the best solution,
but I understand that can be a real challenge. Personally, I live in a
wooded area, remote from vehicle travel and most man-made noises. But,
weather and wind will affect my noise significantly......something I have to
live with.
My vertical and horizontal sensors are simply laying on a concrete floor in
an unattached garage with proper covers over each. Any gain adjustments
raise or lower the noise factor directly. I guess that finding a "happy
level" and living with it is my only solution. But, if there are any
suggestions or remedies out there, I'd appreciate knowing about it..
Best Regards,
Jerry Payton
Is there a way or ways to improve the SNR (signal to noise ratio) =
of an=20
incoming event?
I realize that if the incoming rays are not strong enough, they =
will not=20
overcome the ambient noise of the system.
I would further assume that lowering the ambient noise is the best=20
solution, but I understand that can be a real challenge. =
Personally, I=20
live in a wooded area, remote from vehicle travel and most man-made=20
noises. But, weather and wind will affect my noise=20
significantly......something I have to live with.
My vertical and horizontal sensors are simply laying on a concrete =
floor in=20
an unattached garage with proper covers over each. Any gain =
adjustments=20
raise or lower the noise factor directly. I guess that finding a =
"happy=20
level" and living with it is my only solution. But, if there are =
any=20
suggestions or remedies out there, I'd appreciate knowing about =
it..
Best Regards,
Jerry Payton
Subject: Re: Metods for Improving SNR for events ??
From: ChrisAtUpw@.......
Date: Sun, 17 Sep 2006 15:46:40 EDT
In a message dated 2006/09/17, gpayton880@....... writes:
> Is there a way or ways to improve the SNR (signal to noise ratio) of an
> incoming event?
> I realize that if the incoming rays are not strong enough, they will not
> overcome the ambient noise of the system.
> I would further assume that lowering the ambient noise is the best
> solution, but I understand that can be a real challenge. Personally, I live in a
> wooded area, remote from vehicle travel and most man-made noises. But,
> weather and wind will affect my noise significantly......something I have to live
> with.
> My vertical and horizontal sensors are simply laying on a concrete floor
> in an unattached garage with proper covers over each. Any gain adjustments
> raise or lower the noise factor directly. I guess that finding a "happy level"
> and living with it is my only solution. But, if there are any suggestions or
> remedies out there, I'd appreciate knowing about it..
Hi Jerry,
The usual ways of dealing with excessive ambient noise are to damp /
remove the noise source if practicable / desirable, or to move the equipment to
somewhere which is quieter and / or to also consider lowering the roll off of
the low pass filter. This can be reduced to 2 to 3 Hz OK for practical
purposes. Below this, the filter transmission delays may start to effect your
accuracy and the capacitors get physically bulky.
The problem with wind noise is that it can cover a very wide frequency
/ period range and the amplitude depends strongly on the wind velocity. Check
the ambient noise in quiet periods versus windy periods and take FFTs of the
recordings to see if there are any particular noise peaks involved? Check the
amplifier gain to ensure that you have a background of 100 to 300 counts with
the Lehman. You should be picking up microseisms of maybe 4 to 7 sec period
quite clearly. What sort of vertical sensor / response are you using?
The professionals avoid the surface noise problem by placing their
seismometers in deep boreholes; but in some cases they use large natural caves,
or old mine workings.
You may also want to check for noise on your ADC converter and for any
amplifier noise. Remove the connecting cable from one ADC channel, short the
input, take a recording and see how many bits of noise you have. A good 16 bit
ADC may have less than 1 bit of noise. Poor ones may have +/- 3 bits noise,
or more. Reconnect the amplifier, but put a metal film resistor across the
amplifier input with roughly the same value as the resistance of your coil and
check for amplifier noise. Reconnect your coil, but wedge the arm of the Lehman
stationary and check for EM noise pickup. If you get any, maybe pulses, try
putting an earthed steel cake tin or similar over the pickup coil, or connect a
0.01 to 0.1 mu F ceramic capacitor across the amplifier input terminals. This
is effective for RF pickup.
Am I correct in assuming that your sensor magnet is on the ground and
that the coil is mounted on the seismometer arm? Systems which use a
stationary coil and an unshielded moving magnet on the arm are sensitive to a range of
external noise problems, from pulses on the house power wiring, moving ve
hicles and changes in the Earth's magnetic field, amongst many.
What is the low pass frequency on your amplifier? If you select a
section of the trace and press the FFT button, you should get a ~spectrum and be
able to read off the filter cutoff - or look up the specification?
What quake ranges are you trying ot detect? Far regional and
teleseismic quakes mostly have P waves below 2 to 3 Hz, often about 1 Hz. Local quakes,
local quarrying and local volcanic activity may have components over 20 Hz!
Regards,
Chris Chapman
In a me=
ssage dated 2006/09/17, gpayton880@....... writes:
Is there a w=
ay or ways to improve the SNR (signal to noise ratio) of an incoming event?&=
nbsp;
I realize that if the incoming rays are not strong enough=
, they will not overcome the ambient noise of the system.
I would further assume that lowering the ambient no=
ise is the best solution, but I understand that can be a real challenge. Per=
sonally, I live in a wooded area, remote from vehicle travel and most man-ma=
de noises. But, weather and wind will affect my noise significantly......som=
ething I have to live with.
My vertical and horizontal sensors are simply laying on a=
concrete floor in an unattached garage with proper covers over each. Any ga=
in adjustments raise or lower the noise factor directly. I guess that findin=
g a "happy level" and living with it is my only solution. But, if there are=20=
any suggestions or remedies out there, I'd appreciate knowing about it..
Hi Jerry,
The usual ways of dealing with excessiv=
e ambient noise are to damp / remove the noise source if practicable / desir=
able, or to move the equipment to somewhere which is quieter and / or to als=
o consider lowering the roll off of the low pass filter. This can be reduced=
to 2 to 3 Hz OK for practical purposes. Below this, the filter transmission=
delays may start to effect your accuracy and the capacitors get physically=20=
bulky.
The problem with wind noise is that it=20=
can cover a very wide frequency / period range and the amplitude depends str=
ongly on the wind velocity. Check the ambient noise in quiet periods versus=20=
windy periods and take FFTs of the recordings to see if there are any partic=
ular noise peaks involved? Check the amplifier gain to ensure that you have=20=
a background of 100 to 300 counts with the Lehman. You should be picking up=20=
microseisms of maybe 4 to 7 sec period quite clearly. What sort of vertical=20=
sensor / response are you using?
The professionals avoid the surface noi=
se problem by placing their seismometers in deep boreholes; but in some case=
s they use large natural caves, or old mine workings.
You may also want to check for noise on=
your ADC converter and for any amplifier noise. Remove the connecting cable=
from one ADC channel, short the input, take a recording and see how many bi=
ts of noise you have. A good 16 bit ADC may have less than 1 bit of noise. P=
oor ones may have +/- 3 bits noise, or more. Reconnect the amplifier, but pu=
t a metal film resistor across the amplifier input with roughly the same val=
ue as the resistance of your coil and check for amplifier noise. Reconnect y=
our coil, but wedge the arm of the Lehman stationary and check for EM noise=20=
pickup. If you get any, maybe pulses, try putting an earthed steel cake tin=20=
or similar over the pickup coil, or connect a 0.01 to 0.1 mu F ceramic capac=
itor across the amplifier input terminals. This is effective for RF pickup.<=
BR>
Am I correct in assuming that your sens=
or magnet is on the ground and that the coil is mounted on the seismometer a=
rm? Systems which use a stationary coil and an unshielded moving magnet on t=
he arm are sensitive to a range of external noise problems, from pulses on t=
he house power wiring, moving vehicles and changes in the Earth's magnetic f=
ield, amongst many.
What is the low pass frequency on your=20=
amplifier? If you select a section of the trace and press the FFT button, yo=
u should get a ~spectrum and be able to read off the filter cutoff - or look=
up the specification?
What quake ranges are you trying ot det=
ect? Far regional and teleseismic quakes mostly have P waves below 2 to 3 Hz=
, often about 1 Hz. Local quakes, local quarrying and local volcanic activit=
y may have components over 20 Hz!
Regards,
Chris Chapman
Subject: Re: Metods for Improving SNR for events ??
From: "Connie and Jim Lehman" lehmancj@...........
Date: Sun, 17 Sep 2006 19:41:13 -0400
Jerry--improving SNR is always an ongoing effort in amateur as well as =
professional seismology. In my day of recording we worked with passive =
filters to take out 60 hz and mechanical noise from climate control =
chillers, etc. As long as microseisms were evident, we knew the system =
was working. Here in Virginia we are entertained by variations in =
microseisms from day to day, sometimes hour to hour--hurricanes hitting =
Florida and moving up the coast. Winter storms coming from Tennessee =
eastward to the coast, highs & lows in barometic readings, etc. For =
some unexplained reason, microseismic amplitudes were generally low in =
May to August--we could almost double the gain of amplification--
You speak of your systems on a concrete floor of a garage. I do not =
know your location, but here in VA we ran a long period system under =
those conditions where temperatures varied as much as 30 degrees F. from =
day to night. Not only do componets of the sensor respond, but concrete =
has an amazing way of microscopic shrinking and expanding, and these =
appeared as periodic peaks or snaps on the record. Winds are frequently =
with us, and if trees are within several hundred feet of your sensor, =
the crowns are stressed by wind and this stress is transferred to the =
root systems and propagated to the sensor.
I know there are active filters out there now that work wonders in =
minimizing noise--but I still find myself looking at the microseisms =
before and after an event to give me a frame of reference on the event.
A good day to all Jim Lehman
----- Original Message -----=20
From: Jerry Payton=20
To: PSN-L=20
Sent: Sunday, September 17, 2006 11:00 AM
Subject: Metods for Improving SNR for events ??
Is there a way or ways to improve the SNR (signal to noise ratio) of =
an incoming event? =20
I realize that if the incoming rays are not strong enough, they will =
not overcome the ambient noise of the system.
I would further assume that lowering the ambient noise is the best =
solution, but I understand that can be a real challenge. Personally, I =
live in a wooded area, remote from vehicle travel and most man-made =
noises. But, weather and wind will affect my noise =
significantly......something I have to live with.
My vertical and horizontal sensors are simply laying on a concrete =
floor in an unattached garage with proper covers over each. Any gain =
adjustments raise or lower the noise factor directly. I guess that =
finding a "happy level" and living with it is my only solution. But, if =
there are any suggestions or remedies out there, I'd appreciate knowing =
about it..
Best Regards,
Jerry Payton=20
Jerry--improving SNR is always =
an ongoing=20
effort in amateur as well as professional seismology. In my day of =
recording we worked with passive filters to take out 60 hz and =
mechanical=20
noise from climate control chillers, etc. As long as microseisms =
were=20
evident, we knew the system was working. Here in Virginia we are=20
entertained by variations in microseisms from day to day, sometimes hour =
to=20
hour--hurricanes hitting Florida and moving up the coast. Winter =
storms=20
coming from Tennessee eastward to the coast, highs & lows in =
barometic=20
readings, etc. For some unexplained reason, microseismic =
amplitudes were=20
generally low in May to August--we could almost double the gain of=20
amplification--
You speak of your =
systems on a=20
concrete floor of a garage. I do not know your location, but here =
in VA we=20
ran a long period system under those conditions where temperatures =
varied as=20
much as 30 degrees F. from day to night. Not only do componets of =
the=20
sensor respond, but concrete has an amazing way of microscopic shrinking =
and=20
expanding, and these appeared as periodic peaks or snaps on the =
record. =20
Winds are frequently with us, and if trees are within several =
hundred feet=20
of your sensor, the crowns are stressed by wind and this stress is =
transferred=20
to the root systems and propagated to the sensor.
I know there are =
active=20
filters out there now that work wonders in minimizing noise--but I still =
find=20
myself looking at the microseisms before and after an event to give me a =
frame=20
of reference on the event.
A good day to=20
all &nbs=
p; =20
Jim Lehman
----- Original Message -----
From:=20
Jerry =
Payton=20
Sent: Sunday, September 17, =
2006 11:00=20
AM
Subject: Metods for Improving =
SNR for=20
events ??
Is there a way or ways to improve the SNR (signal to noise ratio) =
of an=20
incoming event?
I realize that if the incoming rays are not strong enough, they =
will not=20
overcome the ambient noise of the system.
I would further assume that lowering the ambient noise is the =
best=20
solution, but I understand that can be a real challenge. =
Personally, I=20
live in a wooded area, remote from vehicle travel and most man-made=20
noises. But, weather and wind will affect my noise=20
significantly......something I have to live with.
My vertical and horizontal sensors are simply laying on a =
concrete floor=20
in an unattached garage with proper covers over each. Any gain=20
adjustments raise or lower the noise factor directly. I guess =
that=20
finding a "happy level" and living with it is my only solution. =
But, if=20
there are any suggestions or remedies out there, I'd appreciate =
knowing about=20
it..
Best Regards,
Jerry Payton
Subject: Re: Metods for Improving SNR for events ??
From: "Geoffrey" gmvoeth@...........
Date: Sun, 17 Sep 2006 23:53:36 -0700
Mr. Jerry Payton;
First:
I would say try to limit your bandwidth
as well make your system flat between
4 seconds and 9 Hz if possible.
Damping small as possible but an absolute necessity.
Increase your system gain until noise
is apparent in the charts.
Limiting your bandwidth to the range of
P waves only instead of everything.
The USGS seems to want only first times of arrivals
and they are looking for the station which
registers closest to the event in question.
Second would be to find an isolated piece
of ground and bury your geophone underground
about 18 inches or so and away (several feet)
from any structures. But a proper chamber is in order
to avoid moisture contamination.
Third is to somehow shield the instruments
from all kinds of disturbances such as
RFI (radio transmitters) and Static (electro static)
Charges and thermal changes.
Noise is the single most important thing
next to calibrating time marks.
But all of this is only my opinion
and not necessarily the absolute truth.
Regards;
geoff
----- Original Message -----
From: "Jerry Payton"
To: "PSN-L"
Sent: Sunday, September 17, 2006 8:00 AM
Subject: Metods for Improving SNR for events ??
> Is there a way or ways to improve the SNR (signal to noise ratio) of an
> incoming event?
>
> I realize that if the incoming rays are not strong enough, they will not
> overcome the ambient noise of the system.
>
> I would further assume that lowering the ambient noise is the best solution,
> but I understand that can be a real challenge. Personally, I live in a
> wooded area, remote from vehicle travel and most man-made noises. But,
> weather and wind will affect my noise significantly......something I have to
> live with.
>
> My vertical and horizontal sensors are simply laying on a concrete floor in
> an unattached garage with proper covers over each. Any gain adjustments
> raise or lower the noise factor directly. I guess that finding a "happy
> level" and living with it is my only solution. But, if there are any
> suggestions or remedies out there, I'd appreciate knowing about it..
>
> Best Regards,
> Jerry Payton
>
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: ebay auction
From: Bob Barns royb1@...........
Date: Wed, 20 Sep 2006 09:59:49 -0400
Hi gang,
Teledyne Geotech Accelerator Seismograph NOAA
Item number: 110035340784
ends Sept 26
Bob
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: My first Sensor
From: "tchannel" tchannel@..............
Date: Wed, 20 Sep 2006 19:49:05 -0600
Hi, I am building a horizontal pendulum sensor, my first attempt. I =
built my own amp and filter. I configured the Low pass filter to Low =
pass 2.5Hz. Before I installed the filter, the sensor would pick up =
footsteps or stomps on the concrete floor, now nothing creates a trace, =
except If I blow on the beam it develops a nice trace. No earthquakes =
since I installed the filter so I don't know if its going to work.
1 I could use some advise, if the amp and filter seem to be okay or if =
I have over done something.
2 Another issue is, I am overwhelmed with confusion about "Seconds vs =
Hz" I understand how to work with them and what they mean. But the =
more I read the more confused I get. The events come in low =
frequencies, 10 to 20seconds is that 0.1Hz. and .05Hz? Does that =
make everything above those Hz, or should I say, below those periods =
unwanted? You can see I need help.
3 Using AmaSies, what values do I set the Low pass filter, and what =
values do I set the high pass filter, for enhancing an enlarged detail =
trace? Do I use both a low and high together.........Some examples =
would be helpful. The little I have use them has just been trial and =
error, to get the best picture.
Many thank, Ted
Hi, I am building a horizontal pendulum =
sensor, my=20
first attempt. I built my own amp and filter. I configured =
the Low=20
pass filter to Low pass 2.5Hz. Before I installed the filter, the =
sensor=20
would pick up footsteps or stomps on the concrete floor, now nothing =
creates=20
a trace, except If I blow on the beam =
it develops=20
a nice trace. No earthquakes since I installed the filter so =
I don't=20
know if its going to work.
1 I could use some advise, if the =
amp and=20
filter seem to be okay or if I have over done something.
2 Another issue is, I am =
overwhelmed with=20
confusion about "Seconds vs Hz" I understand how to work with them =
and=20
what they mean. But the more I =
read the=20
more confused I get. The events come in low frequencies, 10 to=20
20seconds is that 0.1Hz. and .05Hz? Does that =
make=20
everything above those Hz, or should I say, below those periods=20
unwanted? You can see I need help.
3 Using AmaSies, what values do I =
set the Low=20
pass filter, and what values do I set the high pass filter, for =
enhancing an=20
enlarged detail trace? Do I use both a low and high =
together.........Some=20
examples would be helpful. The little I have use them has =
just been=20
trial and error, to get the best picture.
Many thank, Ted
Subject: Re: My first Sensor
From: John Popelish jpopelish@........
Date: Wed, 20 Sep 2006 22:41:33 -0400
tchannel wrote:
> 1 I could use some advise, if the amp and filter
> seem to be okay or if I have over done something.
Two open questions are the damping factor for the pendulum (how many
cycles do you see after you blow on it, before it settles?) and does
your amplifier provide enough gain?
> 2 Another issue is, I am overwhelmed with confusion about
> "Seconds vs Hz"
> I understand how to work with them and what they mean.
> But the more I read the more confused I get.
> The events come in low frequencies,
> 10 to 20seconds is that 0.1Hz. and .05Hz?
Hertz means cycles per second. Seconds can refer to the period of one
cycle (as you use it, above), but it can also refer to time constant
of a filter. Then it refers to seconds per radian. There are 2*pi
radians in a cycle.
> Does that make everything above those Hz,
> or should I say, below those periods unwanted?
> You can see I need help.
>
> 3 Using AmaSies, what values do I set the Low pass filter,
> and what values do I set the high pass filter,
> for enhancing an enlarged detail trace?
> Do I use both a low and high together.........
> Some examples would be helpful.
>
> The little I have use them has just been trial and error,
> to get the best picture.
Someone with more experience in seismology will have to help with these.
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: My first Sensor
From: ChrisAtUpw@.......
Date: Thu, 21 Sep 2006 00:26:11 EDT
In a message dated 21/09/2006, tchannel@.............. writes:
Hi, I am building a horizontal pendulum sensor, my first attempt. I built
my own amp and filter. I configured the Low pass filter to Low pass 2.5Hz.
Before I installed the filter, the sensor would pick up footsteps or stomps on
the concrete floor, now nothing creates a trace, except If I blow on the
beam it develops a nice trace. No earthquakes since I installed the filter so
I don't know if its going to work.
Hi Ted,
I always pays to ask!
What sort of period have you selected for the pendulum? Have you set up
the damping to near 0.7 critical? Are you using oil or magnetic damping?
1 I could use some advise, if the amp and filter seem to be okay or if I
have over done something.
2.5 Hz lowpass is on the low side. It is more common to use 10 Hz for
quiet locations and maybe 5 Hz for urban sites. The filter actually delays the
signal passing through it and you want to keep this to less than 0.2 sec.
What type of filter are you using and how many poles?
Teleseismic quakes usually have P waves of about 1 Hz and S waves fo
about 0.5 Hz. Regional quakes usually have P waves less than 3 Hz, but local
quakes may have components over 20 Hz. The earth absorbs the higher frequencies
preferentially.
2 Another issue is, I am overwhelmed with confusion about "Seconds vs Hz"
I understand how to work with them and what they mean. But the more I read
the more confused I get. The events come in low frequencies, 10 to 20seconds
is that 0.1Hz. and .05Hz? Does that make everything above those Hz, or
should I say, below those periods unwanted? You can see I need help.
Correct. It is just easier to use 10 sec as opposed to 0.1 Hz.
3 Using AmaSies, what values do I set the Low pass filter, and what values
do I set the high pass filter, for enhancing an enlarged detail trace? Do I
use both a low and high together.........Some examples would be helpful.
The little I have use them has just been trial and error, to get the best
picture.
Since you have a real filter at 2.5 Hz, there isn't much point setting
the lowpass filter above this.You may wish to leave the high pass filter
unselected. The P and S waves may have quite low amplitudes. It is common to pick
up the large amplitude Love waves over 10 sec and then search back for the P
and S waves.
You get a microseism background from the ocean between 4 and 8 sec, so
you may want to filter above and below this. Can you take an unfiltered trace
of background and call up an FFT plot of amplitude versus frequency? The
ocean background peak should show up clearly. The period is a bit different for
the west and east coasts. In the middle of the USA, you may see two peaks.
Regards,
Chris Chapman
In a message dated 21/09/2006, tchannel@.............. writes:
<=
FONT=20
style=3D"BACKGROUND-COLOR: transparent" face=3DArial color=3D#000000 size=
=3D2>
Hi, I am building a horizontal pendulum s=
ensor,=20
my first attempt. I built my own amp and filter. I configured=20=
the=20
Low pass filter to Low pass 2.5Hz. Before I installed the filter, th=
e=20
sensor would pick up footsteps or stomps on the concrete floor, now nothin=
g=20
creates a trace, except If I blow on th=
e beam=20
it develops a nice trace. No earthquakes since I installed the=
=20
filter so I don't know if its going to work.
Hi Ted,
I always pays to ask!
What sort of period have you selected for the=20
pendulum? Have you set up the damping to near 0.7 critical? Are you using oi=
l or=20
magnetic damping?
1 I could use som=
e advise, if=20
the amp and filter seem to be okay or if I have over done=20
something.
2.5 Hz lowpass is on the low side. I=
t is=20
more common to use 10 Hz for quiet locations and maybe 5 Hz for urban=20
sites. The filter actually delays the signal passing through it and you=
=20
want to keep this to less than 0.2 sec.=20
What type of filter are you using and how many=20
poles?
Teleseismic quakes usually have P waves of abou=
t 1=20
Hz and S waves fo about 0.5 Hz. Regional quakes usually have P waves less th=
an 3=20
Hz, but local quakes may have components over 20 Hz. The earth absorbs =
the=20
higher frequencies preferentially.
2 Another issue is, I am overwhelme=
d with=20
confusion about "Seconds vs Hz" I understand how to work with them a=
nd=20
what they mean. But the more I re=
ad the=20
more confused I get. The events come in low frequencies, 10 to=20
20seconds is that 0.1Hz. and .05Hz? Does that make=
=20
everything above those Hz, or should I say, below those periods=20
unwanted? You can see I need help.
Correct. It is just easier to use 10 sec as opp=
osed=20
to 0.1 Hz.
<=
FONT=20
style=3D"BACKGROUND-COLOR: transparent" face=3DArial color=3D#000000 size=
=3D2>
3 Using AmaSies, what values do I s=
et the=20
Low pass filter, and what values do I set the high pass filter, for enhanc=
ing=20
an enlarged detail trace? Do I use both a low and high=20
together.........Some examples would be helpful. The little I=20=
have=20
use them has just been trial and error, to get the best=20
picture.
Since you have a real filter at 2.5 Hz, there i=
sn't=20
much point setting the lowpass filter above this.You may wish to leave the h=
igh=20
pass filter unselected. The P and S waves may have quite low amplitudes.&nbs=
p;It=20
is common to pick up the large amplitude Love waves over 10 sec and then sea=
rch=20
back for the P and S waves.
You get a microseism background from the ocean=20
between 4 and 8 sec, so you may want to filter above and below this. Can you=
=20
take an unfiltered trace of background and call up an FFT plot of amplitude=20
versus frequency? The ocean background peak should show up clearly. The peri=
od=20
is a bit different for the west and east coasts. In the middle of the USA, y=
ou=20
may see two peaks.
Regards,
Chris Chapman
Subject: Re: My first Sensor
From: "tchannel" tchannel@..............
Date: Wed, 20 Sep 2006 22:31:06 -0600
Hi John, Thanks for the reply.
Presently it is not dampen at all. I know the importance of this and will
get that going directly, but when I blow on the beam it seems to return to
full stop in maybe 10 to 15 seconds by the clock, producing a nice image,
that does not go on for ever. I was hoping to prove the amp and filter were
working then address the damp. I also am not 100% sure of my natural
frequency of the horz pendulum, I will re adjust it to as close to 5,10 to
20 seconds perhaps tomorrow. When I first set it up I did not know how to
figure it, but I now think I understand the math. I have all the
dimensions, I just need to move it to the bench for a redo.
As to the amp gain, I think it is 100 not sure, The set up I have, right
or wrong, puts out a 1.5V for a low to a 7.5 volts for a high, a pot to
adjust, I set it at 2.0v. I am using the DATAQ which is happy with, 0 to
10 Volts Again the filter is a Low pass set at 2.5Hz. Before using the
same amp with no filter, I would pick up cars on the street and stomps on
the floor. Now nothing unless I blow on the beam or touching the sensor.
Doing that I get nice signal. Maybe with the addition of the filter I need
to increase the voltage to the AD converter, from 2v to 5v?????
Any advise on any issues, or things to be aware of would be of great value,,
Thanks, Ted
----- Original Message -----
From: "John Popelish"
To:
Sent: Wednesday, September 20, 2006 8:41 PM
Subject: Re: My first Sensor
> tchannel wrote:
>
>> 1 I could use some advise, if the amp and filter seem to be okay or if I
>> have over done something.
>
> Two open questions are the damping factor for the pendulum (how many
> cycles do you see after you blow on it, before it settles?) and does your
> amplifier provide enough gain?
>
>> 2 Another issue is, I am overwhelmed with confusion about "Seconds vs
>> Hz"
> > I understand how to work with them and what they mean.
> > But the more I read the more confused I get.
> > The events come in low frequencies,
> > 10 to 20seconds is that 0.1Hz. and .05Hz?
>
> Hertz means cycles per second. Seconds can refer to the period of one
> cycle (as you use it, above), but it can also refer to time constant of a
> filter. Then it refers to seconds per radian. There are 2*pi radians in
> a cycle.
>
>> Does that make everything above those Hz, or should I say, below those
>> periods unwanted?
>
> > You can see I need help.
>>
>> 3 Using AmaSies, what values do I set the Low pass filter,
> > and what values do I set the high pass filter,
> > for enhancing an enlarged detail trace?
> > Do I use both a low and high together.........
> > Some examples would be helpful.
> >
>> The little I have use them has just been trial and error, to get the best
>> picture.
>
> Someone with more experience in seismology will have to help with these.
>
>
> __________________________________________________________
>
> 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: My first Sensor
From: "tchannel" tchannel@..............
Date: Wed, 20 Sep 2006 23:00:32 -0600
Hi Chris, Thanks for the reply, =20
1 What sort of period have you selected for the pendulum? I think =
it is 5 to 15 seconds, I am still trying to fine tune it. =20
=20
2 Have you set up the damping to near 0.7 critical? No damp made =
yet, but hope to use magnets I know the importance of this but was =
hoping to prove the amp and filter first.
3 2.5 Hz lowpass is on the low side.
The amp/filter is still on the breadboard so I can change the values, =
Do you think I should use 10Hz instead of 2.5Hz?
Sorry I don't know how many poles, It goes from a op amp "the filter" =
into another op amp "the amp" with a gain of 100 I think.
and the output voltage is min. 1.4v and max 7.5 volts. I adjust it to =
2vs Into a A/D Converter DATAQ 194 which requires 0 to 10v.
4 Sorry I don't understand this part. I am in Idaho hundreds of miles =
from the ocean, could I still see these?
You get a microseism background from the ocean between 4 and 8 sec, so =
you may want to filter above and below this. Can you take an unfiltered =
trace of background and call up an FFT plot of amplitude versus =
frequency? The ocean background peak should show up clearly. The period =
is a bit different for the west and east coasts. In the middle of the =
USA, you may see two peaks.
Many Thanks, Ted
----- Original Message -----=20
From: ChrisAtUpw@..........
To: psn-l@.................
Sent: Wednesday, September 20, 2006 10:26 PM
Subject: Re: My first Sensor
In a message dated 21/09/2006, tchannel@.............. writes:
Hi, I am building a horizontal pendulum sensor, my first attempt. I =
built my own amp and filter. I configured the Low pass filter to Low =
pass 2.5Hz. Before I installed the filter, the sensor would pick up =
footsteps or stomps on the concrete floor, now nothing creates a trace, =
except If I blow on the beam it develops a nice trace. No earthquakes =
since I installed the filter so I don't know if its going to work.
Hi Ted,
I always pays to ask!=20
What sort of period have you selected for the pendulum? Have you =
set up the damping to near 0.7 critical? Are you using oil or magnetic =
damping?
1 I could use some advise, if the amp and filter seem to be okay =
or if I have over done something.
2.5 Hz lowpass is on the low side. It is more common to use 10 Hz =
for quiet locations and maybe 5 Hz for urban sites. The filter actually =
delays the signal passing through it and you want to keep this to less =
than 0.2 sec.=20
What type of filter are you using and how many poles?
Teleseismic quakes usually have P waves of about 1 Hz and S waves =
fo about 0.5 Hz. Regional quakes usually have P waves less than 3 Hz, =
but local quakes may have components over 20 Hz. The earth absorbs the =
higher frequencies preferentially. =20
2 Another issue is, I am overwhelmed with confusion about "Seconds =
vs Hz" I understand how to work with them and what they mean. But the =
more I read the more confused I get. The events come in low =
frequencies, 10 to 20seconds is that 0.1Hz. and .05Hz? Does that =
make everything above those Hz, or should I say, below those periods =
unwanted? You can see I need help.
Correct. It is just easier to use 10 sec as opposed to 0.1 Hz.
3 Using AmaSies, what values do I set the Low pass filter, and what =
values do I set the high pass filter, for enhancing an enlarged detail =
trace? Do I use both a low and high together.........Some examples =
would be helpful. The little I have use them has just been trial and =
error, to get the best picture.
Since you have a real filter at 2.5 Hz, there isn't much point =
setting the lowpass filter above this.You may wish to leave the high =
pass filter unselected. The P and S waves may have quite low amplitudes. =
It is common to pick up the large amplitude Love waves over 10 sec and =
then search back for the P and S waves.=20
You get a microseism background from the ocean between 4 and 8 =
sec, so you may want to filter above and below this. Can you take an =
unfiltered trace of background and call up an FFT plot of amplitude =
versus frequency? The ocean background peak should show up clearly. The =
period is a bit different for the west and east coasts. In the middle of =
the USA, you may see two peaks.
Regards,
Chris Chapman
Hi Chris, Thanks for the reply,
1 What sort of period have you selected for the=20
pendulum? I think it is 5 to 15 seconds, I am still =
trying to=20
fine tune it.
2 Have you set up the damping to near 0.7 =
critical? =20
No damp made yet, but hope to use magnets I know the importance of =
this=20
but was hoping to prove the amp and filter first.
3 2.5 Hz lowpass is on the low side.
The amp/filter is still on the breadboard so I can change =
the=20
values, Do you think I should use 10Hz instead of 2.5Hz?
Sorry I don't know how many poles, It goes from a op amp "the =
filter"=20
into another op amp "the amp" with a gain of 100 I think.
and the output voltage is min. 1.4v and max 7.5 volts. I =
adjust it to=20
2vs Into a A/D Converter DATAQ 194 which requires 0 to =
10v.
4 Sorry I don't understand this part. I am in Idaho =
hundreds of=20
miles from the ocean, could I still see these?
You get a microseism background from the ocean between 4 and =
8 sec,=20
so you may want to filter above and below this. Can you take an =
unfiltered trace=20
of background and call up an FFT plot of amplitude versus frequency? The =
ocean=20
background peak should show up clearly. The period is a bit different =
for the=20
west and east coasts. In the middle of the USA, you may see two =
peaks.
Many Thanks, Ted
----- Original Message -----
From:=20
ChrisAtUpw@.......
Sent: Wednesday, September 20, =
2006 10:26=20
PM
Subject: Re: My first =
Sensor
In a message dated 21/09/2006,
tchannel@..............=20
writes:Hi, I am building a horizontal =
pendulum sensor,=20
my first attempt. I built my own amp and filter. I =
configured=20
the Low pass filter to Low pass 2.5Hz. Before I installed the =
filter,=20
the sensor would pick up footsteps or stomps on the concrete floor, =
now=20
nothing creates a trace, except =
If I blow on=20
the beam it develops a nice trace. No earthquakes since =
I=20
installed the filter so I don't know if its going to=20
work.
Hi Ted,
I always pays to ask!
What sort of period have you selected for =
the=20
pendulum? Have you set up the damping to near 0.7 critical? Are you =
using oil=20
or magnetic damping?
1 I could =
use some advise,=20
if the amp and filter seem to be okay or if I have over done=20
something.
2.5 Hz lowpass is on the low =
side. It=20
is more common to use 10 Hz for quiet locations and maybe 5 Hz for =
urban=20
sites. The filter actually delays the signal passing through it =
and you=20
want to keep this to less than 0.2 sec.=20
What type of filter are you using and how =
many=20
poles?
Teleseismic quakes usually have P waves =
of about=20
1 Hz and S waves fo about 0.5 Hz. Regional quakes usually have P waves =
less=20
than 3 Hz, but local quakes may have components over 20 Hz. The earth=20
absorbs the higher frequencies =
preferentially.
2 Another issue is, I am =
overwhelmed with=20
confusion about "Seconds vs Hz" I understand how to work with =
them and=20
what they mean. But the =
more I read the=20
more confused I get. The events come in low frequencies, 10 to =
20seconds is that 0.1Hz. and .05Hz? Does =
that make=20
everything above those Hz, or should I say, below those =
periods=20
unwanted? You can see I need=20
help.
Correct. It is just easier to use 10 sec =
as=20
opposed to 0.1 Hz.
3 Using AmaSies, what values =
do I set the=20
Low pass filter, and what values do I set the high pass filter, for=20
enhancing an enlarged detail trace? Do I use both a low and =
high=20
together.........Some examples would be helpful. The =
little I=20
have use them has just been trial and error, to get the best=20
picture.
Since you have a real filter at 2.5 Hz, =
there=20
isn't much point setting the lowpass filter above this.You may wish to =
leave=20
the high pass filter unselected. The P and S waves may have quite low=20
amplitudes. It is common to pick up the large amplitude Love =
waves over=20
10 sec and then search back for the P and S waves.
You get a microseism background from the =
ocean=20
between 4 and 8 sec, so you may want to filter above and below this. =
Can you=20
take an unfiltered trace of background and call up an FFT plot of =
amplitude=20
versus frequency? The ocean background peak should show up clearly. =
The period=20
is a bit different for the west and east coasts. In the middle of the =
USA, you=20
may see two peaks.
Regards,
Chris=20
Chapman
Subject: Re: My first Sensor
From: "Geoffrey" gmvoeth@...........
Date: Wed, 20 Sep 2006 23:03:29 -0700
Hello Ted;
The only thing I can add is that
below Frq:1Hz or Per:1Sec You usually use
Period which is seconds and above that
you use Hertz. You get an infinite range
between 1 and zero for period and
1 and infinity for CPS. But if you want
to do filter calculations I find using
only HZ works just fine. Use a calculator like
the TI 36X Solar or whatever programs
to help you with the filters. I can recommend
a filter ARRL filter program as well as
as LT Spice which are both free, or used to be,
also a spectra program to analyze your noise/filters.
! Hz or !sec is a kind of natural division point
between two worlds so to keep from getting
confused just use Hz if you do any calcs.
The formulas work quite well provided you
have the decimal places to work with (10 or more).
Do not round any intermediate calcs until you
get your final answers.
If your system is set up right then damping is probably
your troubles. But any motion you can see
with the naked eye should send your signal
into saruration and cutoff (clipping)
making a square wave. Overdriving the amplifier
makes good to get first time of arrival
but you cant really see anything else.
I read where Robert Kennedy Played games
with Mr. President (Johnson) not long before
he (R.Kennedy) was Assassinated by placing a
(assumed) ultra-sonic mechinism into a brief case
and holding it on his lap so no recording could
be made. I thing the mechanism he used
Jammed the microphones in the room
driving the preamp into a square wave
essentially deafining the recorders.
This upset the secret service to no end.
Or so i read. This was back in the Early 1960s.
The time of the Buffalo Springfield song
called "For What Its Worth"
Your system should be so sensitive
just blowing on it should drive it into
clipping.
Good Luck.
Regards;
geoff
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: My first Sensor
From: "tchannel" tchannel@..............
Date: Thu, 21 Sep 2006 07:06:48 -0600
Hi, I am making my own amp and filter, what would you suggest for Gain, and
lowpass Hz?
Thanks, Ted
----- Original Message -----
From: "Geoffrey"
To:
Sent: Thursday, September 21, 2006 12:03 AM
Subject: Re: My first Sensor
> Hello Ted;
>
> The only thing I can add is that
> below Frq:1Hz or Per:1Sec You usually use
> Period which is seconds and above that
> you use Hertz. You get an infinite range
> between 1 and zero for period and
> 1 and infinity for CPS. But if you want
> to do filter calculations I find using
> only HZ works just fine. Use a calculator like
> the TI 36X Solar or whatever programs
> to help you with the filters. I can recommend
> a filter ARRL filter program as well as
> as LT Spice which are both free, or used to be,
> also a spectra program to analyze your noise/filters.
> ! Hz or !sec is a kind of natural division point
> between two worlds so to keep from getting
> confused just use Hz if you do any calcs.
> The formulas work quite well provided you
> have the decimal places to work with (10 or more).
> Do not round any intermediate calcs until you
> get your final answers.
>
> If your system is set up right then damping is probably
> your troubles. But any motion you can see
> with the naked eye should send your signal
> into saruration and cutoff (clipping)
> making a square wave. Overdriving the amplifier
> makes good to get first time of arrival
> but you cant really see anything else.
>
> I read where Robert Kennedy Played games
> with Mr. President (Johnson) not long before
> he (R.Kennedy) was Assassinated by placing a
> (assumed) ultra-sonic mechinism into a brief case
> and holding it on his lap so no recording could
> be made. I thing the mechanism he used
> Jammed the microphones in the room
> driving the preamp into a square wave
> essentially deafining the recorders.
> This upset the secret service to no end.
> Or so i read. This was back in the Early 1960s.
> The time of the Buffalo Springfield song
> called "For What Its Worth"
> Your system should be so sensitive
> just blowing on it should drive it into
> clipping.
>
> Good Luck.
>
> 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: My first Sensor
From: ChrisAtUpw@.......
Date: Thu, 21 Sep 2006 23:22:02 EDT
In a message dated 21/09/2006, tchannel@.............. writes:
2 Have you set up the damping to near 0.7 critical? No damp made yet, but
hope to use magnets I know the importance of this but was hoping to prove the
amp and filter first.
Hi Ted,
Without any damping the arm should swing freely for maybe 20 mins. You
time one complete oscillation to ge the period
I have put designs for NdFeB magnetic dampers and high output sensors at
_http://jclahr.com./science/psn/chapman/lehman/index.html_
(http://jclahr.com./science/psn/chapman/lehman/index.html) Both relay type coils and flat
rectangular high linearity coils are considered. The dampers use a horizontally
mounted plate. Copper is preferable, but soft Al will work OK.
What construction and suspension systems are you using?
It is vastly preferable to mount the whole apparatus on one base frame
which can then be adjusted and levelled. See the photo. You need only make the
arm about 2 ft long
3 2.5 Hz lowpass is on the low side.
The amp/filter is still on the breadboard so I can change the values, Do
you think I should use 10Hz instead of 2.5Hz?
I would be inclined to use at least 5 Hz. You can download a free filter
design program and application notes from
_http://focus.ti.com/docs/toolsw/folders/print/filterpro.html_
(http://focus.ti.com/docs/toolsw/folders/print/filterpro.html)
I usually use a 5 pole Bessel design, with the first pole on the
feedback resistor of the low noise input opamp. For a 10 Hz bandwidth, I set the
filter rolloff at 7 Hz.
You can also use a 10 Hz Butterworth filter, but they give about a 10%
overshoot and have extended delays at the roll off frequency.
Environmental noise, which you don't usually want to record, tends to
get serious above about 15 Hz, maybe less in an urban environment, so the
filter needs to reduce the amplitude of these signals quite drastically.
Sorry I don't know how many poles, It goes from a op amp "the filter" into
another op amp "the amp" with a gain of 100 I think.
What low noise input opamp are you using?
What circuit diagram? You need to build in a variable gain from maybe
200 up to several thousand.
I suggest that you check on the frequency and gain specification of
Larry's amplifiers at _http://psn.quake.net_ (http://psn.quake.net)
and the output voltage is min. 1.4v and max 7.5 volts. I adjust it to 2vs
into an AD Converter DATAQ 194 which requires 0 to 10v.
Have you modified your Dataq, or something? The standard DI-194 has
+/-10 V input, but it has only 10 bits resolution. Used in the way you describe,
it will only have a range of about 300 counts!! This is seriously inadequate.
Other experimenters PLEASE NOTE that Dataq are still selling off their
DI-154 +/-10V 12 bit ADCs for $39 at the moment. See _www.dataq.com_
(http://www.dataq.com) This is about the minimum resolution which is useful for
seismic recording, which requires a considerable dynamic range. They are supported
by Amaseis. 16 bit ADCs are preferable.
I am puzzled as to why your are doing this?
You need +/-12 V stabilised supply rails for your opamps!!
4 Sorry I don't understand this part. I am in Idaho hundreds of miles from
the ocean, could I still see these?
You get a microseism background from the ocean between 4 and 8 sec, so you
may want to filter above and below this. Can you take an unfiltered trace of
background and call up an FFT plot of amplitude versus frequency? The ocean
background peak should show up clearly. The period is a bit different for the
west and east coasts. In the middle of the USA, you may see two peaks.
The microseismic background can be observed anywhere on Earth and has an
amplitude of 0.5 to 15 microns, more typically about 1 to 2 microns. The
Pacific coast ones may have shorter periods of 4 to 6 seconds, whereas the
Atlantic ones are often 6 to 8 seconds. You will likely see both in Idaho.
Regards,
Chris Chapman
In a message dated 21/09/2006, tchannel@.............. writes:
<=
FONT=20
style=3D"BACKGROUND-COLOR: transparent" face=3DArial color=3D#000000 size=
=3D2>
2 Have you set up the damping to near 0.7 critical? No dam=
p=20
made yet, but hope to use magnets I know the importance of this but=20=
was=20
hoping to prove the amp and filter first.
Hi Ted,
Without any damping the arm should swing freely=
for=20
maybe 20 mins. You time one complete oscillation to ge the period
I have put designs for NdFeB magnetic dampers a=
nd=20
high output sensors at
http://jcl=
ahr.com./science/psn/chapman/lehman/index.html Both=20
relay type coils and flat rectangular high linearity coils are considered. T=
he=20
dampers use a horizontally mounted plate. Copper is preferable, but soft Al=20=
will=20
work OK.
What construction and suspension systems are yo=
u=20
using?
It is vastly preferable to mount the who=
le=20
apparatus on one base frame which can then be adjusted and levelled. See the=
=20
photo. You need only make the arm about 2 ft long
<=
FONT=20
style=3D"BACKGROUND-COLOR: transparent" face=3DArial color=3D#000000 size=
=3D2>
3 2.5 Hz lowpass is on the low side.
The amp/filter is still on the breadboard so I can change the=20
values, Do you think I should use 10Hz instead of=20
2.5Hz?
I would be inclined to use at least 5 Hz. You c=
an=20
download a free filter design program and application notes from
http:/=
/focus.ti.com/docs/toolsw/folders/print/filterpro.html I usually use a 5 pole Bessel design, with the=20
first pole on the feedback resistor of the low noise input opamp. For a 10 H=
z=20
bandwidth, I set the filter rolloff at 7 Hz.
You can also use a 10 Hz Butterworth filter, bu=
t=20
they give about a 10% overshoot and have extended delays at the roll off=20
frequency.
Environmental noise, which you don't usually wa=
nt=20
to record, tends to get serious above about 15 Hz, maybe less in an urban=20
environment, so the filter needs to reduce the amplitude of these signals qu=
ite=20
drastically.
Sorry I don't know how many poles, It goes from a op amp "the=
=20
filter" into another op amp "the amp" with a gain of 100 I think.
What low noise input opamp are you using?
What circuit diagram? You need to build in a=20
variable gain from maybe 200 up to several thousand.
I suggest that you check on the frequency=20=
and=20
gain specification of Larry's amplifiers at
http://psn.quake.netand the output voltage is min. 1.4v and max 7.5 volts. I adjust=20=
it=20
to 2vs into an AD Converter DATAQ 194 which requires 0 to=20
10v.
Have you modified your Dataq, or something? The=
=20
standard DI-194 has +/-10 V input, but it has only 10 bits resolution. Used=20=
in=20
the way you describe, it will only have a range of about 300 counts!! This i=
s=20
seriously inadequate.
Other experimenters PLEASE NOTE that Dataq are=20
still selling off their
DI-154 +/-10V 12 bit ADCs for $39 at the=20
moment. See
www.dataq.com This is a=
bout=20
the
minimum resolution which is useful for seismic recording, which=20
requires a considerable dynamic range. They are supported by Amaseis. 1=
6=20
bit ADCs are preferable.
I am puzzled as to why your are doing this?
You need +/-12 V stabilised supply rails for=
=20
your opamps!!
<=
FONT=20
style=3D"BACKGROUND-COLOR: transparent" face=3DArial color=3D#000000 size=
=3D2>
4 Sorry I don't understand this part. I am in Idaho hundre=
ds=20
of miles from the ocean, could I still see these?
You get a microseism background from the ocean between 4 and 8=20=
sec,=20
so you may want to filter above and below this. Can you take an unfiltered=
=20
trace of background and call up an FFT plot of amplitude versus frequency?=
The=20
ocean background peak should show up clearly. The period is a bit differen=
t=20
for the west and east coasts. In the middle of the USA, you may see two=20
peaks.
The microseismic background can be observed=20
anywhere on Earth and has an amplitude of 0.5 to 15 microns, more=20
typically about 1 to 2 microns. The Pacific coast ones may have shorter peri=
ods=20
of 4 to 6 seconds, whereas the Atlantic ones are often 6 to 8 seconds. You w=
ill=20
likely see both in Idaho.
Regards,
Chris Chapman
Subject: Fwd: Re: seismometer
From: John or Jan Lahr JohnJan@........
Date: Fri, 22 Sep 2006 13:18:25 -0700
Can anyone help Sebastian at the Exploratorium with an EV-17 sensor?
Thanks,
John
>From: "Sebastian Martin"
>Subject: Re: seismometer
>To: John Lahr
>X-Mailer: CommuniGate Pro WebUser Interface v.4.2.8
>Date: Fri, 22 Sep 2006 12:55:46 -0700
>X-SA-PROB: 0
>X-SA-MPREASON: sender enabled (sebastianm@..................
>
>Hello John,
>
>we are doing fine with the as1 exhibit. I am using software from
>dataq to show different time scales.
>
>We just got an ev17 force balance seismometer (electrotech) in here,
>and dont know how to connect it correctly. Seems there is only one
>input (500 ohm resistance), the other input is a short.
>
>So we dont know how to give it power and get feedback through the
>same input...
>
>Do you have any idea where to find a datasheet? I cant find anything
>on the web.
>
>Best
>Sebastian
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Long-, short- and now broad-band-record of COR
From: John or Jan Lahr JohnJan@........
Date: Fri, 22 Sep 2006 14:13:50 -0700
ASL has made an unfiltered version of the Corvallis station (COR)
available so now
one can toggle between broad band (unfiltered), short period, and long period
versions.
I think this is very instructive.
http://www.jclahr.com/science/psn/cor/index.html
Cheers,
John
#################################/ John C. Lahr
################################/ Emeritus Seismologist
###############################/ U.S. Geological Survey
==========================/ Central Region Geologic Hazards Team
#############################//#################################
############################//##################################
PO Box 548 /###################################
Corvallis, Oregon 97339 /===============================
Phone: (541) 758-2699 /####################################
Cell: (541) 740-4844 /#####################################
Fax: (928) 569-0113 /######################################
jjpub@........ /#######################################
http://jclahr.com/science/
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: seismometer
From: ChrisAtUpw@.......
Date: Fri, 22 Sep 2006 22:44:03 EDT
In a message dated 22/09/2006, JohnJan@........ writes:
>We just got an ev17 force balance seismometer (electrotech) in here,
>and don't know how to connect it correctly. Seems there is only one
>input (500 ohm resistance), the other input is a short.
Hi there,
There are EV-17 references on psn. Try typing EV-17 seismometer into
google.
As far as I can remember the EV-17 was a 1 Hz geophone type with a
calibration coil, not a full force balance system.
_http://www.seismicnet.com/psnlist/020128_160720_1.html_
(http://www.seismicnet.com/psnlist/020128_160720_1.html)
_http://www.seismicnet.com/psnlist/020128_171420_1.html_
(http://www.seismicnet.com/psnlist/020128_171420_1.html)
Regards,
Chris Chapman
In a message dated 22/09/2006, JohnJan@........ writes:
<=
FONT=20
style=3D"BACKGROUND-COLOR: transparent" face=3DArial color=3D#000000 size=
=3D2>>We=20
just got an ev17 force balance seismometer (electrotech) in here,
>=
and=20
don't know how to connect it correctly. Seems there is only one
>in=
put=20
(500 ohm resistance), the other input is a short.
<=
/DIV>
Hi there,
There are EV-17 references on psn. Try typing E=
V-17=20
seismometer into google.
As far as I can remember the EV-17 was a 1 Hz=20
geophone type with a calibration coil, not a full force balance system.
http://www.s=
eismicnet.com/psnlist/020128_160720_1.html
http://www.s=
eismicnet.com/psnlist/020128_171420_1.html
Regards,
Chris Chapman
Subject: Border Patrol Use Of Seismic Sensors
From: "Geoffrey" gmvoeth@...........
Date: Sat, 23 Sep 2006 02:33:33 -0700
I understand the US Border Patrol has used
seismic sensors for a long time now to watch
certain areas of the border for intruders/interlopers
and I was wondering what is the sensors they
are using (make and model or type or manufacturer)? Does anyone know ??
I can imagine the military doing this too
around nuclear sites and such
critical areas where sensitive
information is being collected/stored.
I happen to know that geiger counters can now
use semiconductor sensors instead of those old
delicate tubes with relatively short lives
due to the organic quenching gases.
So I can imagine there exists today
sensors we have never seen before that are
far superior to what us amateurs have been
exposed.
Why cant a seismic sensor be built into
a microchip somehow ??
Have the experts in the field of science
(scientists) ever experimented here ?
Are there any military secrets related to Geology ?
(that might help us)
Anyone here know anything about the future of
vibration sensors sensitive enough and low noise enough
down to or below the seismic
noise level ?
Regards;
Geoff
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Border Patrol Use Of Seismic Sensors
From: "Connie and Jim Lehman" lehmancj@...........
Date: Sat, 23 Sep 2006 10:27:53 -0400
Geoff--just a few thoughts here on sensitivity with proximity detectors of
motion type. I don't have a lot of experience with them, but the 3
dimensional accelerometers--that's the closest to a chip I have seen)--
highly amplified I am sure would do the trick 30 paces or more away.
Probably with regular instrumental amplifiers a buried mike at two feet
would copy surface motion within 50 ft. In our work, we were looking for
running water in underground limestone channels. Of course one has to put
up with false alarms of animals, wind,rain--(rain sounds unique 2 ft
under!!!) Etc.
Best wishes, Jim Lehman
----- Original Message -----
From: "Geoffrey"
To: "PSN"
Sent: Saturday, September 23, 2006 5:33 AM
Subject: Border Patrol Use Of Seismic Sensors
> I understand the US Border Patrol has used
> seismic sensors for a long time now to watch
> certain areas of the border for intruders/interlopers
> and I was wondering what is the sensors they
> are using (make and model or type or manufacturer)? Does anyone know ??
>
> I can imagine the military doing this too
> around nuclear sites and such
> critical areas where sensitive
> information is being collected/stored.
>
> I happen to know that geiger counters can now
> use semiconductor sensors instead of those old
> delicate tubes with relatively short lives
> due to the organic quenching gases.
> So I can imagine there exists today
> sensors we have never seen before that are
> far superior to what us amateurs have been
> exposed.
>
>
> Why cant a seismic sensor be built into
> a microchip somehow ??
>
> Have the experts in the field of science
> (scientists) ever experimented here ?
>
> Are there any military secrets related to Geology ?
> (that might help us)
>
> Anyone here know anything about the future of
> vibration sensors sensitive enough and low noise enough
> down to or below the seismic
> noise level ?
>
> 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: Seismograph for school
From: "John Patskan" jcpatskan@.........
Date: Sat, 23 Sep 2006 12:12:14 -0700
Hello,
I am thinking of trying to buid a seisomgraph for my son's school. I have
quite a bit of experience in shallow exploration geophysic's, mostly
electrical and electromagnetic, but none in seismology. I ahve searched the
internet and found quite a few resources.
I have also noticed a seismograph (or strong motion accelerameter) on sale
at e-bay, with an opening bid of $75. It is apparently an old unit that was
surplused from NOAA. It is made by Teledyne Geotech and uses a film
recorder. The seller admits to knwing nothing about it. Does anyone know
anything about these units. Would it be difficult to convert to recording
on a computer?
Thanks
John P
Hello,
I am thinking of trying to buid a seisomgraph for my son's school. I have quite a bit of experience in shallow exploration geophysic's, mostly electrical and electromagnetic, but none in seismology. I ahve searched the internet and found quite a few resources.
I have also noticed a seismograph (or strong motion accelerameter) on sale at e-bay, with an opening bid of $75. It is apparently an old unit that was surplused from NOAA. It is made by Teledyne Geotech and uses a film recorder. The seller admits to knwing nothing about it. Does anyone know anything about these units. Would it be difficult to convert to recording on a computer?
Thanks
John P
Subject: RE: Border Patrol Use Of Seismic Sensors
From: "Bob Hancock" carpediem1@.........
Date: Sat, 23 Sep 2006 13:47:21 -0700
The use of seismic sensors to find intruders dates back to the Vietnam War.
They were placed along the Ho Chi Min trail, a network of paths from North
Vietnam to South Vietnam that also crossed into Laos and Cambodia. The
sensors were modified US Navy sonobuoys, and about 20,000 were dropped along
the trail. There were two versions, one stuck into the ground like a lawn
dart, and the other was dropped by parachute, and could remain above ground.
The signals were picked up by nearby airplanes and relayed to ground
stations.
Bob Hancock
Three Points, AZ
-----Original Message-----
From: psn-l-request@.............. [mailto:psn-l-request@............... On
Behalf Of Connie and Jim Lehman
Sent: Saturday, September 23, 2006 07:28
To: psn-l@..............
Subject: Re: Border Patrol Use Of Seismic Sensors
Geoff--just a few thoughts here on sensitivity with proximity detectors of
motion type. I don't have a lot of experience with them, but the 3
dimensional accelerometers--that's the closest to a chip I have seen)--
highly amplified I am sure would do the trick 30 paces or more away.
Probably with regular instrumental amplifiers a buried mike at two feet
would copy surface motion within 50 ft. In our work, we were looking for
running water in underground limestone channels. Of course one has to put
up with false alarms of animals, wind,rain--(rain sounds unique 2 ft
under!!!) Etc.
Best wishes, Jim Lehman
----- Original Message -----
From: "Geoffrey"
To: "PSN"
Sent: Saturday, September 23, 2006 5:33 AM
Subject: Border Patrol Use Of Seismic Sensors
> I understand the US Border Patrol has used
> seismic sensors for a long time now to watch
> certain areas of the border for intruders/interlopers
> and I was wondering what is the sensors they
> are using (make and model or type or manufacturer)? Does anyone know ??
>
> I can imagine the military doing this too
> around nuclear sites and such
> critical areas where sensitive
> information is being collected/stored.
>
> I happen to know that geiger counters can now
> use semiconductor sensors instead of those old
> delicate tubes with relatively short lives
> due to the organic quenching gases.
> So I can imagine there exists today
> sensors we have never seen before that are
> far superior to what us amateurs have been
> exposed.
>
>
> Why cant a seismic sensor be built into
> a microchip somehow ??
>
> Have the experts in the field of science
> (scientists) ever experimented here ?
>
> Are there any military secrets related to Geology ?
> (that might help us)
>
> Anyone here know anything about the future of
> vibration sensors sensitive enough and low noise enough
> down to or below the seismic
> noise level ?
>
> 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)
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Seismograph for school
From: jimo17@........
Date: Sat, 23 Sep 2006 13:56:15 -0700
Hi John- That is a strong motion instrument and not much (any) value...
Try these 3 sites as I have bought systems from all 3 for schools and
they are quite good and very reliable...Jim
PS- write me off line sometime and we can talk geophysics...
Dave Saum in VA $200 seismograph
http://www.infiltec.com/seismo/infqm45a.htm
A real sophisticated system is found at Larry Cochranes site in CA for
~$500:
http://psn.quake.net/
http://psn.quake.net/#Equipment
Mauro Mariottis site in Italy
http://mariottim.interfree.it/index_e.htm
Jim O'Donnell
Geological/Geophysical Consultant
GEOTECHNICAL APPLICATIONS
702.293.5664 702.281.9081 cell
geophysics@..........
jimo17@........
On Sat, 23 Sep 2006 12:12:14 -0700 "John Patskan"
writes:
Hello,
I am thinking of trying to buid a seisomgraph for my son's school. I
have quite a bit of experience in shallow exploration geophysic's, mostly
electrical and electromagnetic, but none in seismology. I ahve searched
the internet and found quite a few resources.
I have also noticed a seismograph (or strong motion accelerameter) on
sale at e-bay, with an opening bid of $75. It is apparently an old unit
that was surplused from NOAA. It is made by Teledyne Geotech and uses a
film recorder. The seller admits to knwing nothing about it. Does anyone
know anything about these units. Would it be difficult to convert to
recording on a computer?
Thanks
John P
Hi John- That is a strong motion instrument and not much (any)=20
value...
Try these 3 sites as I have bought systems from all 3 for schools and =
they=20
are quite good and very reliable...Jim
PS- write me off line sometime and we can talk geophysics...
Dave Saum in VA $200 seismograph
http://www.infiltec.=
com/seismo/infqm45a.htm
A real sophisticated system is found at Larry Cochrane=92s site in CA for=
=20
~$500:
http://psn.quake.net/
http://psn.quake.net/#Equipment
Mauro Mariotti=92s site =
in=20
Italy
http://mariottim.=
interfree.it/index_e.htm
Jim O'Donnell
Geological/Geophysical Consultant
GEOTECHNICAL APPLICATIONS
702.293.5664 702.281.9081 cell
geophysics@..........
On Sat, 23 Sep 2006 12:12:14 -0700 "John Patskan" <
jcpatskan@.........> writes:
Hello,
I am thinking of trying to buid a seisomgraph for my =
son's=20
school. I have quite a bit of experience in shallow exploration=20
geophysic's, mostly electrical and electromagnetic, but none in =
seismology.=20
I ahve searched the internet and found quite a few resources.=20
I have also noticed a=20
seismograph (or strong motion accelerameter) on sale =
at=20
e-bay, with an opening bid of $75. It is apparently an old unit =
that was=20
surplused from NOAA. It is made by Teledyne Geotech and uses a film=
=20
recorder. The seller admits to knwing nothing about it. Does anyone=
know=20
anything about these units. Would it be difficult to convert to=20
recording on a computer?
Thanks
John P
Subject: Re: Border Patrol Use Of Seismic Sensors
From: ChrisAtUpw@.......
Date: Sat, 23 Sep 2006 17:54:00 EDT
In a message dated 23/09/2006, gmvoeth@........... writes:
I understand the US Border Patrol has used seismic sensors for a long time
now to watch certain areas of the border for intruders / interlopers and I was
wondering what is the sensors they are using (make and model or type or
manufacturer)?
Hi Geoff,
Probably 8 to 10 Hz See _http://www.geospacelp.com/industry2.shtml#geo_
(http://www.geospacelp.com/industry2.shtml#geo)
HSJ, GS20 etc, are quoted for 'intruder detection', but I have no direct
knowledge.
I can imagine the military doing this too around nuclear sites and such
critical areas where sensitive information is being collected / stored.
Why can't a seismic sensor be built into a microchip somehow ?
You can't get the low noise and the high sensitivity, partly due to gas
interactions in very small spaces and partly due to intrinsic material noise.
You also have Brownian noise / kT / frequency considerations. This may limit
you to weights of about an ounce.
Have the experts in the field of science ever experimented here ?
I would have expected them to have tried quite hard. The hysteretic
limitations of materials are fundamental and inherent, so their success is likely
to be limited.
Horizontal seismometer noise may be limited by the earth tides amongst
other disturbances, which cyclically alter the slope of the ground / angle of
gravity slightly. This noise may be 20 dB above the minimum vertical noise,
but it is fairly broadband in it's effects. See the annual noise plots from
seismic stations.
So we make a highly sensitive vertical sensor, where the mass is
balanced by a spring force. The dimensions of the apparatus are temperature
dependant and the spring constant is temperature dependant, but neither are strictly
linear, or of comparable magnitude. In general, it may not be too difficult
to reduce temperature effects by a factor of 10, but any further improvement
gets progressively much more difficult. Throw in the fact that springs do not
behave truly elastically and the whole problem gets quite difficult. Springs
with a very low temperature coefficient are inherently magnetic, which can
add other sources of noise. The STS1 probably represents about the best that
can be done commercially.
Are there any military secrets related to Geology ?
Don't know of any, but I would doubt it, due to the known fundamental
limitations of the properties of materials.
Anyone here know anything about the future of vibration sensors sensitive
enough and low noise enough down to or below the seismic noise level ?
The only candidates that I know of are PZT piezoelectric crystals and simple
pendulum developments. PZT crystals have quite a high temperature
dependence. You need to hold the temperature very constant.
Since the output of coil / magnet induction sensors goes to zero as the
frequency goes to zero, the use of direct position sensors has become
commonplace. The use of very low drift / low noise / long life semiconductor
circuits is essential. Magnetic sensors (LVDT) may be limited to about 10^-10 m due
to their inherent Barkhausen (domain switching) noise. Capacitative sensors
may, with considerable effort, give another couple of orders of magnitude
sensitivity, but they still depend on the expansion rate of materials for their
stability. Fused quartz coated with various metals and silver plated Invar are
known plate materials.
Using velocity damping derived by differentiating the position signal is
inherently noisy. Providing electromagnetic damping directly is quieter and
it is relatively easy to do with NdFeB or Sm/Co magnet arrays.
The move from coil springs of the LaCoste type to leaf springs of the
Streckheisen type enabled the 'parasitic vibration' responses to be reduced. A
bent sheet of copper plate close to a leaf spring may be used to stabilise
the temperature. Small NdFeB magnets may be stuck to the leaf spring to provide
inductive damping with the copper plate.
Some additional research may well be desirable on suspension systems and
on overall designs to minimise the effects of intrinsic noise. The
realisation that seismic sensors do not follow the 'standard' damping curve has quite
profound implications. Extending the period of 'simple' vertical pendulums
may offer significant advances, but high performance linear capacitative
sensors are needed. See _http://physics.mercer.edu/hpage/peters.html_
(http://physics.mercer.edu/hpage/peters.html) We may need to provide a 'build it
yourself' general purpose design; maybe a circuit board?
Regards,
Chris Chapman
In a message dated 23/09/2006, gmvoeth@........... writes:
<=
FONT=20
style=3D"BACKGROUND-COLOR: transparent" face=3DArial color=3D#000000 size=
=3D2>I=20
understand the US Border Patrol has used seismic sensors for a long time n=
ow=20
to watch certain areas of the border for intruders / interlopers and I was=
=20
wondering what is the sensors they are using (make and model or type or=20
manufacturer)?
Hi Geoff,
Probably 8 to 10 Hz See
http://www.geospacelp=
..com/industry2.shtml#geo HSJ, GS20 etc, are quoted for 'intruder detecti=
on',=20
but I have no direct knowledge.
<=
FONT=20
style=3D"BACKGROUND-COLOR: transparent" face=3DArial color=3D#000000 size=
=3D2>I can=20
imagine the military doing this too around nuclear sites and such
criti=
cal=20
areas where sensitive information is being collected / stored.
Why=20
can't a seismic sensor be built into a microchip somehow ?
You can't get the low noise and the high=20
sensitivity, partly due to gas interactions in very small spaces and partly=20=
due=20
to intrinsic material noise. You also have Brownian noise / kT / frequency=20
considerations. This may limit you to weights of about an ounce.
<=
FONT=20
style=3D"BACKGROUND-COLOR: transparent" face=3DArial color=3D#000000 size=
=3D2>Have the=20
experts in the field of science ever experimented here ?
I would have expected them to have tried quite=20
hard. The hysteretic limitations of materials are fundamental and inher=
ent,=20
so their success is likely to be limited.
Horizontal seismometer noise may be limite=
d by=20
the earth tides amongst other disturbances, which cyclically alter the slope=
of=20
the ground / angle of gravity slightly. This noise may be 20 dB above the=20
minimum vertical noise, but it is fairly broadband in it's effects. See the=20
annual noise plots from seismic stations.
So we make a highly sensitive vertical sensor,=20
where the mass is balanced by a spring force. The dimensions of the=20
apparatus are temperature dependant and the spring constant is temperature=20
dependant, but neither are strictly linear, or of comparable magnitude. In=20
general, it may not be too difficult to reduce temperature effects by a fact=
or=20
of 10, but any further improvement gets progressively much more difficult. T=
hrow=20
in the fact that springs do not behave truly elastically and the whole probl=
em=20
gets quite difficult. Springs with a very low temperature coefficient are=20
inherently magnetic, which can add other sources of noise. The STS1=20
probably represents about the best that can be done commercially.
<=
FONT=20
style=3D"BACKGROUND-COLOR: transparent" face=3DArial color=3D#000000 size=
=3D2>Are=20
there any military secrets related to Geology ?
Don't know of any, but I would doubt it, due to=
the=20
known fundamental limitations of the properties of materials.
<=
FONT=20
style=3D"BACKGROUND-COLOR: transparent" face=3DArial color=3D#000000 size=
=3D2>Anyone=20
here know anything about the future of vibration sensors sensitive enough=20=
and=20
low noise enough down to or below the seismic noise level=20
?
The only candidates that I know of are PZT=20
piezoelectric crystals and simple pendulum developments. PZT crystals h=
ave=20
quite a high temperature dependence. You need to hold the temperature v=
ery=20
constant.
Since the output of coil / magnet induction sen=
sors=20
goes to zero as the frequency goes to zero, the use of direct position senso=
rs=20
has become commonplace. The use of very low drift / low noise / long=20
life semiconductor circuits is essential. Magnetic sensors (LVDT)=20=
may=20
be limited to about 10^-10 m due to their inherent Barkhausen (domain switch=
ing)=20
noise. Capacitative sensors may, with considerable effort, give another=
=20
couple of orders of magnitude sensitivity, but they still depend on the=20
expansion rate of materials for their stability. Fused quartz coated with=20
various metals and silver plated Invar are known plate materials.
Using velocity damping derived by=20
differentiating the position signal is inherently noisy. Providing=20
electromagnetic damping directly is quieter and it is relatively easy to do=20=
with=20
NdFeB or Sm/Co magnet arrays.
The move from coil springs of the LaCoste type=20=
to=20
leaf springs of the Streckheisen type enabled the 'parasitic vibration'=20
responses to be reduced. A bent sheet of copper plate close to a leaf spring=
may=20
be used to stabilise the temperature. Small NdFeB magnets may be stuck to th=
e=20
leaf spring to provide inductive damping with the copper plate.
Some additional research may well be desirable=20=
on=20
suspension systems and on overall designs to minimise the effects of intrins=
ic=20
noise. The realisation that seismic sensors do not follow the 'standard' dam=
ping=20
curve has quite profound implications. Extending the period of 'simple' vert=
ical=20
pendulums may offer significant advances, but high performance linear=20
capacitative sensors are needed. See
http://physics.mercer.e=
du/hpage/peters.html =20
We may need to provide a 'build it yourself' general purpose design; maybe a=
=20
circuit board?
Regards,
Chris Chapman
Subject: RE: Border Patrol Use Of Seismic Sensors
From: "Bob Hancock" carpediem1@.........
Date: Sat, 23 Sep 2006 15:33:38 -0700
Chris / Geoff -
The KS-36000 tri-axle, bore-hole seismometer was developed to detect
underground nuclear explosions. The follow-on instrument is the KS-54000.
This is one method of detecting violations of the Nuclear Test Ban Treaty,
so I guess you could say that Department of Defense has an interest in
seismology.
Bob Hancock
Three Points, AZ
_____
From: psn-l-request@.............. [mailto:psn-l-request@............... On
Behalf Of ChrisAtUpw@.......
Sent: Saturday, September 23, 2006 14:54
To: psn-l@..............
Subject: Re: Border Patrol Use Of Seismic Sensors
In a message dated 23/09/2006, gmvoeth@........... writes:
I understand the US Border Patrol has used seismic sensors for a long time
now to watch certain areas of the border for intruders / interlopers and I
was wondering what is the sensors they are using (make and model or type or
manufacturer)?
Hi Geoff,
Probably 8 to 10 Hz See http://www.geospacelp.com/industry2.shtml#geo
HSJ, GS20 etc, are quoted for 'intruder detection', but I have no direct
knowledge.
I can imagine the military doing this too around nuclear sites and such
critical areas where sensitive information is being collected / stored.
Why can't a seismic sensor be built into a microchip somehow ?
You can't get the low noise and the high sensitivity, partly due to gas
interactions in very small spaces and partly due to intrinsic material
noise. You also have Brownian noise / kT / frequency considerations. This
may limit you to weights of about an ounce.
Have the experts in the field of science ever experimented here ?
I would have expected them to have tried quite hard. The hysteretic
limitations of materials are fundamental and inherent, so their success is
likely to be limited.
Horizontal seismometer noise may be limited by the earth tides amongst
other disturbances, which cyclically alter the slope of the ground / angle
of gravity slightly. This noise may be 20 dB above the minimum vertical
noise, but it is fairly broadband in it's effects. See the annual noise
plots from seismic stations.
So we make a highly sensitive vertical sensor, where the mass is
balanced by a spring force. The dimensions of the apparatus are temperature
dependant and the spring constant is temperature dependant, but neither are
strictly linear, or of comparable magnitude. In general, it may not be too
difficult to reduce temperature effects by a factor of 10, but any further
improvement gets progressively much more difficult. Throw in the fact that
springs do not behave truly elastically and the whole problem gets quite
difficult. Springs with a very low temperature coefficient are inherently
magnetic, which can add other sources of noise. The STS1 probably represents
about the best that can be done commercially.
Are there any military secrets related to Geology ?
Don't know of any, but I would doubt it, due to the known fundamental
limitations of the properties of materials.
Anyone here know anything about the future of vibration sensors sensitive
enough and low noise enough down to or below the seismic noise level ?
The only candidates that I know of are PZT piezoelectric crystals and
simple pendulum developments. PZT crystals have quite a high temperature
dependence. You need to hold the temperature very constant.
Since the output of coil / magnet induction sensors goes to zero as the
frequency goes to zero, the use of direct position sensors has become
commonplace. The use of very low drift / low noise / long life semiconductor
circuits is essential. Magnetic sensors (LVDT) may be limited to about
10^-10 m due to their inherent Barkhausen (domain switching) noise.
Capacitative sensors may, with considerable effort, give another couple of
orders of magnitude sensitivity, but they still depend on the expansion rate
of materials for their stability. Fused quartz coated with various metals
and silver plated Invar are known plate materials.
Using velocity damping derived by differentiating the position signal is
inherently noisy. Providing electromagnetic damping directly is quieter and
it is relatively easy to do with NdFeB or Sm/Co magnet arrays.
The move from coil springs of the LaCoste type to leaf springs of the
Streckheisen type enabled the 'parasitic vibration' responses to be reduced.
A bent sheet of copper plate close to a leaf spring may be used to stabilise
the temperature. Small NdFeB magnets may be stuck to the leaf spring to
provide inductive damping with the copper plate.
Some additional research may well be desirable on suspension systems and
on overall designs to minimise the effects of intrinsic noise. The
realisation that seismic sensors do not follow the 'standard' damping curve
has quite profound implications. Extending the period of 'simple' vertical
pendulums may offer significant advances, but high performance linear
capacitative sensors are needed. See
http://physics.mercer.edu/hpage/peters.html We may need to provide a 'build
it yourself' general purpose design; maybe a circuit board?
Regards,
Chris Chapman
Chris / Geoff =
–
The KS-36000 tri-axle, bore-hole
seismometer was developed to detect underground nuclear =
explosions. The
follow-on instrument is the KS-54000. This is one method of =
detecting
violations of the Nuclear Test Ban Treaty, so I guess you could say that =
Department
of Defense has an interest in seismology.
Bob =
Hancock
Three Points, =
AZ
From:
psn-l-request@.............. [mailto:psn-l-request@............... =
On Behalf Of =
ChrisAtUpw@.......
Sent: Saturday, September =
23, 2006
14:54
To: psn-l@..............
Subject: Re: Border =
Patrol Use Of
Seismic Sensors
In a message dated 23/09/2006,
gmvoeth@........... writes:
I understand the US Border Patrol =
has
used seismic sensors for a long time now to watch certain areas of the =
border
for intruders / interlopers and I was wondering what is the sensors they =
are
using (make and model or type or =
manufacturer)?
HSJ, GS20 =
etc,
are quoted for 'intruder detection', but I have no direct =
knowledge.
I can imagine the military doing =
this too
around nuclear sites and such
critical areas where sensitive information is being collected / =
stored.
Why can't a seismic sensor be built into a microchip somehow =
?
You can't =
get the
low noise and the high sensitivity, partly due to gas interactions in =
very
small spaces and partly due to intrinsic material noise. You also have =
Brownian
noise / kT / frequency considerations. This may limit you to weights of =
about
an ounce.
Have the experts in the field of =
science
ever experimented here ?
I would =
have
expected them to have tried quite hard. The hysteretic limitations of =
materials
are fundamental and inherent, so their success is likely to be =
limited.
Horizontal
seismometer noise may be limited by the earth tides amongst other
disturbances, which cyclically alter the slope of the ground / angle of =
gravity
slightly. This noise may be 20 dB above the minimum vertical noise, but =
it is
fairly broadband in it's effects. See the annual noise plots from =
seismic
stations.
So we make =
a
highly sensitive vertical sensor, where the mass is balanced by a =
spring
force. The dimensions of the apparatus are temperature dependant and the =
spring
constant is temperature dependant, but neither are strictly linear, or =
of
comparable magnitude. In general, it may not be too difficult to reduce
temperature effects by a factor of 10, but any further improvement gets
progressively much more difficult. Throw in the fact that springs do not =
behave
truly elastically and the whole problem gets quite difficult. Springs =
with a
very low temperature coefficient are inherently magnetic, which can add =
other
sources of noise. The STS1 probably represents about the best that =
can be
done commercially.
Are there any military secrets =
related to
Geology ?
Don't know =
of
any, but I would doubt it, due to the known fundamental limitations of =
the
properties of materials.
Anyone here know anything about =
the
future of vibration sensors sensitive enough and low noise enough down =
to or
below the seismic noise level ?
The only
candidates that I know of are PZT piezoelectric crystals and simple =
pendulum
developments. PZT crystals have quite a high temperature =
dependence.
You need to hold the temperature very =
constant.
Since the =
output
of coil / magnet induction sensors goes to zero as the frequency goes to =
zero,
the use of direct position sensors has become commonplace. The use of =
very low
drift / low noise / long life semiconductor circuits is =
essential. Magnetic
sensors (LVDT) may be limited to about 10^-10 m due to their inherent
Barkhausen (domain switching) noise. Capacitative sensors may, with
considerable effort, give another couple of orders of magnitude
sensitivity, but they still depend on the expansion rate of materials =
for their
stability. Fused quartz coated with various metals and silver plated =
Invar are
known plate materials.
Using =
velocity
damping derived by differentiating the position signal is =
inherently
noisy. Providing electromagnetic damping directly is quieter and it is
relatively easy to do with NdFeB or Sm/Co magnet =
arrays.
The move =
from
coil springs of the LaCoste type to leaf springs of the Streckheisen =
type
enabled the 'parasitic vibration' responses to be reduced. A bent sheet =
of
copper plate close to a leaf spring may be used to stabilise the =
temperature.
Small NdFeB magnets may be stuck to the leaf spring to provide inductive
damping with the copper plate.
Some =
additional
research may well be desirable on suspension systems and on overall =
designs to
minimise the effects of intrinsic noise. The realisation that seismic =
sensors
do not follow the 'standard' damping curve has quite profound =
implications.
Extending the period of 'simple' vertical pendulums may offer =
significant
advances, but high performance linear capacitative sensors are needed. =
See http://physics.merce=
r.edu/hpage/peters.html
We may need to provide a 'build it yourself' general purpose design; =
maybe a
circuit board?
Subject: Re: Seismograph for school
From: ChrisAtUpw@.......
Date: Sat, 23 Sep 2006 19:09:33 EDT
In a message dated 23/09/2006, jcpatskan@......... writes:
I am thinking of trying to build a seismograph for my son's school. I have
quite a bit of experience in shallow exploration geophysic's, mostly
electrical and electromagnetic, but none in seismology. I have searched the internet
and found quite a few resources.
Hi John,
You might consider making a medium sized Lehman - about 2 ft long? Say
about 1.5 sec period that can be extended to 20 sec?
You will need +/-12V stabilised power supplies of you may buy an
amplifier and transformer from Larry at _http://psn.quake.net_ (http://psn.quake.net)
Since it will be used with other school systems, I suggest that you use
Amaseis and buy a DI-154 12 bit ADC still at just $39! _www.dataq.com_
(http://www.dataq.com) Amaseis supports this ADC.
See _http://jclahr.com/science/psn/as1/index.html_
(http://jclahr.com/science/psn/as1/index.html)
Use magnetic damping, NOT oil.
Use an all metal braced single unit costruction - NO plastic structural
components - NO separated sections.
Your choice of suspension system is critical. NEITHER a point on a plane
NOR knife edge systems are satisfactory - avoid them like the plague. Most
other systems are OK to good. You need to be able to get a period of at least
20 seconds.
Have a look at _http://jclahr.com/science/psn/chapman/lehman/index.html_
(http://jclahr.com/science/psn/chapman/lehman/index.html)
and _http://jclahr.com/science/psn/chapman/index.html_
(http://jclahr.com/science/psn/chapman/index.html)
and _http://www.jclahr.com/science/psn/cor_psn.html_
(http://www.jclahr.com/science/psn/cor_psn.html)
and _http://jclahr.com/science/psn/_ (http://jclahr.com/science/psn/)
ALSO _http://www.mgm.monschau.de/seismic/english/artikel/artikel_1_4.php_
(http://www.mgm.monschau.de/seismic/english/artikel/artikel_1_4.php) and
sequels
I have also noticed a seismograph (or strong motion accelerometer) on
sale at e-bay, with an opening bid of $75.
I suggest that you forget this one! You do not need a strong motion
sensor - or the headaches of converting an optical one. This might be called
'buying trouble'!
Good Luck!
Chris Chapman
In a message dated 23/09/2006, jcpatskan@......... writes:
<=
FONT=20
style=3D"BACKGROUND-COLOR: transparent" face=3DArial color=3D#000000 size=
=3D2>I am=20
thinking of trying to build a seismograph for my son's school. I have=
=20
quite a bit of experience in shallow exploration geophysic's, mostly=20
electrical and electromagnetic, but none in seismology. I have searc=
hed=20
the internet and found quite a few resources.
Hi John,
You might consider making a medium sized Lehman=
-=20
about 2 ft long? Say about 1.5 sec period that can be extended to 20 sec?
You will need +/-12V stabilised power supplies=20=
of=20
you may buy an amplifier and transformer from Larry at
http://psn.quake.net
Since it will be used with other school systems=
, I=20
suggest that you use
Amaseis and buy a DI-154 12 bit A=
DC=20
still at just $39! www.dataq.com Amaseis supports this ADC.
See
http://jclahr.com/scie=
nce/psn/as1/index.html
Use magnetic damping, NOT oil.
Use an all metal braced single unit costruction=
-=20
NO plastic structural components - NO separated sections.
Your choice of suspension system is critical. NEITHE=
R a=20
point on a plane NOR knife edge systems are satisfactory - avoid them like t=
he=20
plague. Most other systems are OK to good. You need to be able to get a peri=
od=20
of at least 20 seconds.
Have a look at
http://jcla=
hr.com/science/psn/chapman/lehman/index.html and
http://jclahr.com/=
science/psn/chapman/index.html and
http://www.jclahr.co=
m/science/psn/cor_psn.html and
http://jclahr.com/science/psn/
ALSO
=
http://www.mgm.monschau.de/seismic/english/artikel/artikel_1_4.php =
and=20
sequels
I have also noticed a=20
seismograph (or strong motion accelerometer) on sale at=20
e-bay, with an opening bid of $75.
I suggest that you forget=20=
this=20
one! You do not need a strong motion sensor - or the headaches of=20
converting an optical one. This might be called 'buying trouble'!
Good Luck!
Chris Chapman
Subject: Re: Seismograph for school
From: "tchannel" tchannel@..............
Date: Sat, 23 Sep 2006 20:40:36 -0600
Hi Chris, What sort of "choice of suspension system" would you =
recommend? Is there a detail I can look at?=20
I have only seen the knife edge style.
Thanks, Ted
----- Original Message -----=20
From: ChrisAtUpw@..........
To: psn-l@.................
Sent: Saturday, September 23, 2006 5:09 PM
Subject: Re: Seismograph for school
In a message dated 23/09/2006, jcpatskan@......... writes:
I am thinking of trying to build a seismograph for my son's school. =
I have quite a bit of experience in shallow exploration geophysic's, =
mostly electrical and electromagnetic, but none in seismology. I have =
searched the internet and found quite a few resources.=20
Hi John,
You might consider making a medium sized Lehman - about 2 ft long? =
Say about 1.5 sec period that can be extended to 20 sec?
You will need +/-12V stabilised power supplies of you may buy an =
amplifier and transformer from Larry at http://psn.quake.net
Since it will be used with other school systems, I suggest that =
you use Amaseis and buy a DI-154 12 bit ADC still at just $39! =
www.dataq.com Amaseis supports this ADC.
See http://jclahr.com/science/psn/as1/index.html
Use magnetic damping, NOT oil.
Use an all metal braced single unit costruction - NO plastic =
structural components - NO separated sections.
Your choice of suspension system is critical. NEITHER a point on a =
plane NOR knife edge systems are satisfactory - avoid them like the =
plague. Most other systems are OK to good. You need to be able to get a =
period of at least 20 seconds.
Have a look at =
http://jclahr.com/science/psn/chapman/lehman/index.html
and http://jclahr.com/science/psn/chapman/index.html
and http://www.jclahr.com/science/psn/cor_psn.html
and http://jclahr.com/science/psn/
ALSO =
http://www.mgm.monschau.de/seismic/english/artikel/artikel_1_4.php and =
sequels
I have also noticed a seismograph (or strong motion accelerometer) =
on sale at e-bay, with an opening bid of $75. =20
I suggest that you forget this one! You do not need a strong =
motion sensor - or the headaches of converting an optical one. This =
might be called 'buying trouble'!
Good Luck!
Chris Chapman
Hi Chris, What sort of "choice of suspension system" would =
you=20
recommend? Is there a detail I can look at?
I have only seen the knife edge style.
Thanks, Ted
----- Original Message -----
From:=20
ChrisAtUpw@.......
Sent: Saturday, September 23, =
2006 5:09=20
PM
Subject: Re: Seismograph for =
school
In a message dated 23/09/2006,
jcpatskan@......... =
writes:Hi John,
You might consider making a medium sized =
Lehman -=20
about 2 ft long? Say about 1.5 sec period that can be extended to 20=20
sec?
You will need +/-12V stabilised power =
supplies of=20
you may buy an amplifier and transformer from Larry at
http://psn.quake.net
Since it will be used with other school =
systems,=20
I suggest that you use
Amaseis and buy a DI-154 =
12 bit=20
ADC
still at just $39! www.dataq.com Amaseis supports this =
ADC. See
http://jclahr.com/s=
cience/psn/as1/index.html
Use magnetic damping, NOT oil.
Use an all metal braced single unit =
costruction -=20
NO plastic structural components - NO separated sections.
Your choice of suspension system is critical. =
NEITHER=20
a point on a plane NOR knife edge systems are satisfactory - avoid =
them like=20
the plague. Most other systems are OK to good. You need to be able to =
get a=20
period of at least 20 seconds.
Have a look at
http://j=
clahr.com/science/psn/chapman/lehman/index.html and
http://jclahr.c=
om/science/psn/chapman/index.html and
http://www.jclahr=
..com/science/psn/cor_psn.html and
http://jclahr.com/science/psn/
ALSO
http://www.mgm.monschau.de/seismic/english/artikel/artikel_1_4.php=
and=20
sequels
I have also noticed a=20
seismograph (or strong motion accelerometer) on =
sale at=20
e-bay, with an opening bid of $75.
I suggest that you =
forget=20
this one! You do not need a strong motion sensor - or the =
headaches of=20
converting an optical one. This might be called 'buying =
trouble'!
Good Luck!
Chris Chapman
Subject: Re: Border Patrol Use Of Seismic Sensors
From: "Geoffrey" gmvoeth@...........
Date: Sun, 24 Sep 2006 13:02:55 -0700
Hello Bob Hancock;
This all makes common sense.
What types of sensors were used ?
Piezo, Magnetic, Something we never heard of before ?
Who manufactured these devices ?
Could they sense seismic events as well as human disturbances ?
Maybe someone could show us a readout that an
operator/technician might see ??
US Sonobuoys were only monitored for spectrum content
then threats were determined through identifying
the various components of a given spectrum
with whatever. Such a database was the calassified
part of the works and thats not what I am looking for
here. Just want a new idea to get first time of arrivals
for P waves.
It seems to me that in the military calibration and intelligence
was more impoirtant to them then hardware alone.
They gave meanings to things that if I were to say the
same thing to a civilian that civilian would call me crazy
and lock me away.
We need details about their hardware.
Especially the sensors.
Like some sonar elements are what you
call magnetostrictive which is simply
a block of nickle surrounded in a coil of
wire and when you put that metal in a
magnetic field it will change in dimension.
I have never heard of magnetostrictive devices
being used in seismology ???
Are there sensors suitable for seismology that
us amateures have never heard of before ??
Michealson interferometers, electron microscopes ???
Magnetic Levatation ??
Any knowledge there beyond us amateures ?
Regards;
geoff
----- Original Message -----
From: "Bob Hancock"
To:
Sent: Saturday, September 23, 2006 1:47 PM
Subject: RE: Border Patrol Use Of Seismic Sensors
> The use of seismic sensors to find intruders dates back to the Vietnam War.
> They were placed along the Ho Chi Min trail, a network of paths from North
> Vietnam to South Vietnam that also crossed into Laos and Cambodia. The
> sensors were modified US Navy sonobuoys, and about 20,000 were dropped along
> the trail. There were two versions, one stuck into the ground like a lawn
> dart, and the other was dropped by parachute, and could remain above ground.
> The signals were picked up by nearby airplanes and relayed to ground
> stations.
>
> Bob Hancock
> Three Points, AZ
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Border Patrol Use Of Seismic Sensors
From: "Geoffrey" gmvoeth@...........
Date: Sun, 24 Sep 2006 13:47:15 -0700
Hi Bob;
I suspect those devices cost thousands of dollars
because it is the drive of most people who
deal with Government to rip Uncle Sam off.
Because Uncle Sams makeup is always changing
they seem able to get away with it.
These items if they are borehole need to be 100
or more feet down and who has the money
in the amateur world to get a driller
to drill such a hole.
I cant even afford to get a new drywell
if I might ever need one.
Maybe I should have included the idea
in my original thought as being something
we might build or obtain for our own use.
The USGS had these 500# seismometers that are
quite good and used to put them all over
the earth. If I had a decent place to keep one
Id try to get one of those.
They are quite large and need to be kept
out of the dampness and away from temp changes.
You cant easily move one from one place to another.
I think these 500# devices were used for that
nuclear thing you talk about.
You should have special underground building
just for this seismometer.
Regards;
Geoff
----- Original Message -----
From: "Bob Hancock"
To:
Sent: Saturday, September 23, 2006 3:33 PM
Subject: RE: Border Patrol Use Of Seismic Sensors
>
>
> Chris / Geoff -
>
>
>
> The KS-36000 tri-axle, bore-hole seismometer was developed to detect
> underground nuclear explosions. The follow-on instrument is the KS-54000.
> This is one method of detecting violations of the Nuclear Test Ban Treaty,
> so I guess you could say that Department of Defense has an interest in
> seismology.
>
>
>
> Bob Hancock
>
> Three Points, AZ
>
>
>
> _____
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Border Patrol Use Of Seismic Sensors
From: "Geoffrey" gmvoeth@...........
Date: Sun, 24 Sep 2006 13:34:34 -0700
> Probably 8 to 10 Hz See _http://www.geospacelp.com/industry2.shtml#geo_
> (http://www.geospacelp.com/industry2.shtml#geo)
> HSJ, GS20 etc, are quoted for 'intruder detection', but I have no direct
> knowledge.
I have an HS 10 similar to the one shown
and like it best of any other I have tried.
You can get them down to 0.75Hz I believe
But they cost like $3000 USD new. You might get one used
and in questionable shape for 1/10 that cost.
> Why can't a seismic sensor be built into a microchip somehow ?
> You can't get the low noise and the high sensitivity, partly due to gas
> interactions in very small spaces and partly due to intrinsic material noise.
> You also have Brownian noise / kT / frequency considerations. This may limit
> you to weights of about an ounce.
Im not sure this is true, You can create a vacuum
and eliminate all brownian motion I think
Like the old vacuum tubes you create the best
vacuum mechanically possible then use a "getter"
to eliminate as much as possible the remaining gasses.
then, Use some form of damping not involving brownian motions.
>
> So we make a highly sensitive vertical sensor, where the mass is
> balanced by a spring force. The dimensions of the apparatus are temperature
> dependant and the spring constant is temperature dependant, but neither are strictly
> linear, or of comparable magnitude. In general, it may not be too difficult
> to reduce temperature effects by a factor of 10, but any further improvement
> gets progressively much more difficult. Throw in the fact that springs do not
> behave truly elastically and the whole problem gets quite difficult. Springs
> with a very low temperature coefficient are inherently magnetic, which can
> add other sources of noise. The STS1 probably represents about the best that
> can be done commercially.
All we are looking for here is an unquestionable mark
for first time of arrival and not the whole seismic signal.
That would be the Pn wave for regional/local I think.
P or Pp waves for teleseismic events.
One would have to coordinate/compare with others
to determine the validity of any received signals.
> Using velocity damping derived by differentiating the position signal is
> inherently noisy. Providing electromagnetic damping directly is quieter and
> it is relatively easy to do with NdFeB or Sm/Co magnet arrays.
Yes, I like this way too.
>
> The move from coil springs of the LaCoste type to leaf springs of the
> Streckheisen type enabled the 'parasitic vibration' responses to be reduced. A
> bent sheet of copper plate close to a leaf spring may be used to stabilise
> the temperature. Small NdFeB magnets may be stuck to the leaf spring to provide
> inductive damping with the copper plate.
You are getting way too complex for what i call amateure here.
Amateures do not make money off their sport and may be only a layman
with an interest in whatever area.
What you talk about here is in the relm of the physicist
or his loyal engineers.
>
> Some additional research may well be desirable on suspension systems and
> on overall designs to minimise the effects of intrinsic noise. The
> realisation that seismic sensors do not follow the 'standard' damping curve has quite
> profound implications. Extending the period of 'simple' vertical pendulums
> may offer significant advances, but high performance linear capacitative
> sensors are needed. See _http://physics.mercer.edu/hpage/peters.html_
> (http://physics.mercer.edu/hpage/peters.html) We may need to provide a 'build it
> yourself' general purpose design; maybe a circuit board?
>
> Regards,
>
> Chris Chapman
Whatever happened to that scientific idea that simpler is better and more reliable ?
Thanks for your response;
Regards;
geoff
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: RE: Border Patrol Use Of Seismic Sensors
From: "Bob Hancock" carpediem1@.........
Date: Sun, 24 Sep 2006 15:03:29 -0700
Hi Geoff -
I know the USGS has ordered a large number of receivers from Guralp. I
believe they are CMG 3 series, but I am not certain what sub series. They
are part of a project which will place sensors all over the country in a
grid format, and then periodically move the sensors to another area.
Bob Hancock
Three Points, AZ
-----Original Message-----
From: psn-l-request@.............. [mailto:psn-l-request@............... On
Behalf Of Geoffrey
Sent: Sunday, September 24, 2006 13:47
To: psn-l@..............
Subject: Re: Border Patrol Use Of Seismic Sensors
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Border Patrol Use Of Seismic Sensors
From: ChrisAtUpw@.......
Date: Sun, 24 Sep 2006 21:37:45 EDT
In a message dated 24/09/2006 22:06:39 GMT Daylight Time,
gmvoeth@........... writes:
> Why can't a seismic sensor be built into a microchip somehow ?
> You can't get the low noise and the high sensitivity, partly due to gas
> interactions in very small spaces and partly due to intrinsic material
noise.
> You also have Brownian noise / kT / frequency considerations. This may
limit
> you to weights of about an ounce.
I'm not sure this is true, You can create a vacuum
and eliminate all brownian motion I think
Hi Geoff,
You need some gas present to cool the silicon wafers and you may also
need to ~damp the response. The Brownian motion is caused by the seismometer
being at room temperature. You are 'stuck' with it. To get rid of it, you would
need to cool the seismometer to absolute zero -273C.
I understand that trying to minaturise accelerometers down to silicon
chip size has several problems, one of which is that their properties don't
quite 'scale' as simple calculations.
> So we make a highly sensitive vertical sensor, where the mass is
> balanced by a spring force. The dimensions of the apparatus are
temperature
> dependant and the spring constant is temperature dependant, but neither
are strictly
> linear, or of comparable magnitude. In general, it may not be too
difficult
> to reduce temperature effects by a factor of 10, but any further
improvement
> gets progressively much more difficult. Throw in the fact that springs do
not
> behave truly elastically and the whole problem gets quite difficult.
Springs
> with a very low temperature coefficient are inherently magnetic, which
can
> add other sources of noise. The STS1 probably represents about the best
that
> can be done commercially.
All we are looking for here is an unquestionable mark
for first time of arrival and not the whole seismic signal.
No, we need to be able to record the whole seismic signal. I am just
pointing out that the 'simple' mechanical properties are not quite linear, so
when you try to compensate them out, the non linear bits become of major
importance.
> The move from coil springs of the LaCoste type to leaf springs of the
> Streckheisen type enabled the 'parasitic vibration' responses to be
reduced. A
> bent sheet of copper plate close to a leaf spring may be used to
stabilise
> the temperature. Small NdFeB magnets may be stuck to the leaf spring to
provide
> inductive damping with the copper plate.
You are getting way too complex for what I call amateurs here.
Amateurs do not make money off their sport and may be only a layman
with an interest in whatever area.
Some amateurs have tried and succeeded very well! Have a look at
_http://www.bryantlabs.net/seismo.html_ (http://www.bryantlabs.net/seismo.html) and
_http://www.eas.slu.edu/People/STMorrissey/index.html_
(http://www.eas.slu.edu/People/STMorrissey/index.html)
Whatever happened to that scientific idea that simpler is better and more
reliable ?
Alive and well, but we have to take the world as we find it, not as we
would wish it to be! Mathematicians may describe simple harmonic motion quite
clearly, but your average pendulum seems to be rather deaf!
Regards,
Chris Chapman
In a message dated 24/09/2006 22:06:39 GMT Daylight Time,=20
gmvoeth@........... writes:
<=
FONT=20
style=3D"BACKGROUND-COLOR: transparent" face=3DArial color=3D#000000 size=
=3D2>>=20
Why can't a seismic sensor be built into a microchip somehow=20
?
> You can't get the low noise and the high sensitivit=
y,=20
partly due to gas
> interactions in very small spaces and partly du=
e to=20
intrinsic material noise.
> You also have Brownian noise / kT /=20
frequency considerations. This may limit
> you to weights of about=20=
an=20
ounce.
I'm not sure this is true, You can create a vacuum
and=20
eliminate all brownian motion I think
Hi Geoff,
You need some gas present to cool the sili=
con=20
wafers and you may also need to ~damp the response. The Brownian motion=
is=20
caused by the seismometer being at room temperature. You are 'stuck' with it=
.. To=20
get rid of it, you would need to cool the seismometer to absolute=20=
zero=20
-273C.
I understand that trying to minaturise=20
accelerometers down to silicon chip size has several problems, one of which=20=
is=20
that their properties don't quite 'scale' as simple calculations.
<=
FONT=20
style=3D"BACKGROUND-COLOR: transparent" face=3DArial color=3D#000000=20
size=3D2>> So we make a highly sensitive vertical sensor,&=
nbsp;=20
where the mass is
> balanced by a spring force. The dimensions of=20
the apparatus are temperature
> dependant and the spring cons=
tant=20
is temperature dependant, but neither are strictly
> linear,=20=
or=20
of comparable magnitude. In general, it may not be too difficult=20
> to reduce temperature effects by a factor of 10, but any=20
further improvement
> gets progressively much more difficult. Throw=
in=20
the fact that springs do not
> behave truly elastically and the who=
le=20
problem gets quite difficult. Springs
> with a very low temperature=
=20
coefficient are inherently magnetic, which can
> add other=20
sources of noise. The STS1 probably represents about the best that
>=
;=20
can be done commercially.
All we are looking for here is an=20
unquestionable mark
for first time of arrival and not the whole seismic=
=20
signal.
No, we need to be able to record the whole seis=
mic=20
signal. I am just pointing out that the 'simple' mechanical properties are n=
ot=20
quite linear, so when you try to compensate them out, the non linear bits be=
come=20
of major importance.
<=
FONT=20
style=3D"BACKGROUND-COLOR: transparent" face=3DArial color=3D#000000=20
size=3D2>> The move from coil springs of the LaCoste type=20
to leaf springs of the
> Streckheisen type enabled the 'paras=
itic=20
vibration' responses to be reduced. A
> bent sheet of copper=20
plate close to a leaf spring may be used to stabilise
> the=20
temperature. Small NdFeB magnets may be stuck to the leaf spring to=20
provide
> inductive damping with the copper plate.
You are=20
getting way too complex for what I call amateurs here.
Amateurs do not=20=
make=20
money off their sport and may be only a layman
with an interest in what=
ever=20
area.
Some amateurs have tried and succeeded very wel=
l!=20
Have a look at
http://www.bryantlabs.net/sei=
smo.html and=20
http://www.eas=
..slu.edu/People/STMorrissey/index.html Alive and well, but we have to take the world a=
s we=20
find it, not as we would wish it to be! Mathematicians may describe simple=20
harmonic motion quite clearly, but your average pendulum seems to be rather=20
deaf!=20
Regards,
Chris Chapman
Thanks for the tips.
I believe I will try to build the Lehaman style unit.
This is actually an elementary school. It used to be an Environmental Science magnet school, and they still have room they call the Eco-Lab. Each class goes in there once a week and the teachers have them work on some project. This year the teachers decided on a Geology theme. I thought a seismograph would be nice to have in the lab. Actually I think the homemade one would be better because the kids could get a better idea of how it works. They wouldn't be doing anything in depth but I thought seeing there own siesmograph records may spark some interest in science. I Haven't approached the teachers yet as I want to make sure I can pull it off first.
John P
On 9/23/06, tchannel <tchannel@..............> wrote:
Hi Chris, What sort of "choice of suspension system" would you recommend? Is there a detail I can look at?
I have only seen the knife edge style.
Thanks, Ted
----- Original Message -----
Sent: Saturday, September 23, 2006 5:09 PM
Subject: Re: Seismograph for school
I am thinking of trying to build a seismograph for my son's school. I have quite a bit of experience in shallow exploration geophysic's, mostly electrical and electromagnetic, but none in seismology. I have searched the internet and found quite a few resources.
Hi John,
You might consider making a medium sized Lehman - about 2 ft long? Say about 1.5 sec period that can be extended to 20 sec?
You will need +/-12V stabilised power supplies of you may buy an amplifier and transformer from Larry at
http://psn.quake.net
Since it will be used with other school systems, I suggest that you use
Amaseis and buy a DI-154 12 bit ADC
still at just $39! www.dataq.com Amaseis supports this ADC.
Use magnetic damping, NOT oil.
Use an all metal braced single unit costruction - NO plastic structural components - NO separated sections.
Your choice of suspension system is critical. NEITHER a point on a plane NOR knife edge systems are satisfactory - avoid them like the plague. Most other systems are OK to good. You need to be able to get a period of at least 20 seconds.
I have also noticed a seismograph (or strong motion accelerometer) on sale at e-bay, with an opening bid of $75.
I suggest that you forget this one! You do not need a strong motion sensor - or the headaches of converting an optical one. This might be called 'buying trouble'!
Good Luck!
Chris Chapman
Subject: Re: Seismograph for school
From: "tchannel" tchannel@..............
Date: Tue, 26 Sep 2006 08:38:22 -0600
Hi John, Ted here, and I am one month into a similar project, using my =
own money, for a non profit organization.
We are having a lot of fun on the project, but the electronics are =
challenging, even though I have worked on circuits, I thought I was up =
to it electronic task, but now I am not sure. I have made some =
progress however, so I think I am getting closer.
I am happy to share my successes and failures if you would like to =
correspond. Ted
----- Original Message -----=20
From: John Patskan=20
To: psn-l@.................
Sent: Monday, September 25, 2006 11:11 PM
Subject: Re: Seismograph for school
Hello everyone,
Thanks for the tips.
I believe I will try to build the Lehaman style unit.
This is actually an elementary school. It used to be an Environmental =
Science magnet school, and they still have room they call the Eco-Lab. =
Each class goes in there once a week and the teachers have them work on =
some project. This year the teachers decided on a Geology theme. I =
thought a seismograph would be nice to have in the lab. Actually I =
think the homemade one would be better because the kids could get a =
better idea of how it works. They wouldn't be doing anything in depth =
but I thought seeing there own siesmograph records may spark some =
interest in science. I Haven't approached the teachers yet as I want to =
make sure I can pull it off first.=20
John P
On 9/23/06, tchannel wrote:
Hi Chris, What sort of "choice of suspension system" would you =
recommend? Is there a detail I can look at?=20
I have only seen the knife edge style.=20
Thanks, Ted
----- Original Message -----=20
From: ChrisAtUpw@..........
To: psn-l@.................
Sent: Saturday, September 23, 2006 5:09 PM
Subject: Re: Seismograph for school=20
In a message dated 23/09/2006, jcpatskan@......... writes:
I am thinking of trying to build a seismograph for my son's =
school. I have quite a bit of experience in shallow exploration =
geophysic's, mostly electrical and electromagnetic, but none in =
seismology. I have searched the internet and found quite a few =
resources.=20
Hi John,
You might consider making a medium sized Lehman - about 2 ft =
long? Say about 1.5 sec period that can be extended to 20 sec?
You will need +/-12V stabilised power supplies of you may buy =
an amplifier and transformer from Larry at http://psn.quake.net
Since it will be used with other school systems, I suggest =
that you use Amaseis and buy a DI-154 12 bit ADC still at just $39! =
www.dataq.com Amaseis supports this ADC.=20
See http://jclahr.com/science/psn/as1/index.html
Use magnetic damping, NOT oil.=20
Use an all metal braced single unit costruction - NO plastic =
structural components - NO separated sections.
Your choice of suspension system is critical. NEITHER a point =
on a plane NOR knife edge systems are satisfactory - avoid them like the =
plague. Most other systems are OK to good. You need to be able to get a =
period of at least 20 seconds.=20
Have a look at =
http://jclahr.com/science/psn/chapman/lehman/index.html=20
and http://jclahr.com/science/psn/chapman/index.html
and http://www.jclahr.com/science/psn/cor_psn.html
and http://jclahr.com/science/psn/
ALSO =
http://www.mgm.monschau.de/seismic/english/artikel/artikel_1_4.php and =
sequels
I have also noticed a seismograph (or strong motion =
accelerometer) on sale at e-bay, with an opening bid of $75. =20
I suggest that you forget this one! You do not need a strong =
motion sensor - or the headaches of converting an optical one. This =
might be called 'buying trouble'!
Good Luck!
Chris Chapman
Hi John, Ted here, and I am one =
month into a=20
similar project, using my own money, for a non profit =
organization.
We are having a lot of fun on the =
project, but the=20
electronics are challenging, even though I have worked on circuits, I =
thought I=20
was up to it electronic task, but now I am not sure. I have =
made=20
some progress however, so I think I am getting closer.
I am happy to share my successes and =
failures if=20
you would like to correspond. Ted
----- Original Message -----
From:=20
John=20
Patskan Sent: Monday, September 25, =
2006 11:11=20
PM
Subject: Re: Seismograph for =
school
Hello everyone,
Thanks for the tips.
I =
believe I=20
will try to build the Lehaman style unit.
This is actually an=20
elementary school. It used to be an Environmental Science magnet =
school,=20
and they still have room they call the Eco-Lab. Each class goes =
in there=20
once a week and the teachers have them work on some project. =
This year=20
the teachers decided on a Geology theme. I thought a seismograph =
would=20
be nice to have in the lab. Actually I think the homemade one =
would be=20
better because the kids could get a better idea of how it works. =
They=20
wouldn't be doing anything in depth but I thought seeing there own =
siesmograph=20
records may spark some interest in science. I Haven't approached =
the=20
teachers yet as I want to make sure I can pull it off first. =
John=20
P
On 9/23/06, tchannel <tchannel@..............>=20
wrote:
Hi Chris, What sort of "choice of suspension system" =
would you=20
recommend? Is there a detail I can look at?
I have only seen the knife edge style.
Thanks, Ted
----- Original Message ----- =
From: ChrisAtUpw@.......=20
Sent: Saturday, =
September 23,=20
2006 5:09 PM
Subject: Re: =
Seismograph for=20
school
In a message dated 23/09/2006,
jcpatskan@............
writes:
Hi John,
You might consider making a medium =
sized=20
Lehman - about 2 ft long? Say about 1.5 sec period that can be =
extended to=20
20 sec?
You will need +/-12V stabilised power =
supplies of you may buy an amplifier and transformer from Larry at =
http://psn.quake.net
Since it will be used with other =
school=20
systems, I suggest that you use
Amaseis and =
buy a=20
DI-154 12 bit ADC
still at just $39! www.dataq.com =
Amaseis=20
supports this ADC. See
http://jclahr.com/science/psn/as1/index.html
Use magnetic damping, NOT oil.
Use an all metal braced single unit=20
costruction - NO plastic structural components - NO separated=20
sections.
Your choice of suspension system is =
critical.=20
NEITHER a point on a plane NOR knife edge systems are satisfactory =
- avoid=20
them like the plague. Most other systems are OK to good. You need =
to be=20
able to get a period of at least 20 seconds.
Have a look at
http://jclahr.com/science/psn/chapman/lehman/index.html=20
and
http://jclahr.com/science/psn/chapman/index.html
and
http://www.jclahr.com/science/psn/cor_psn.html and
http://jclahr.com/science/psn/
ALSO
http://www.mgm.monschau.de/seismic/english/artikel/artike=
l_1_4.php=20
and sequels
I have also noticed a=20
seismograph (or strong motion accelerometer) =
on sale=20
at e-bay, with an opening bid of $75.
I suggest that you=20
forget this one! You do not need a strong =
motion=20
sensor - or the headaches of converting an optical one. This might =
be=20
called 'buying trouble'!
Good Luck!
Chris Chapman
=
Subject: Earthquake swarm
From: =?ISO-8859-1?Q?J=F3n_Fr=EDmann?= jonfr500@.........
Date: Tue, 26 Sep 2006 15:12:32 +0000
Hi all
There is a earthquake swarm going on in the Bardarbungu volcano fissure
system. So far ~125 earthquakes have been recorded, two largest onces
where M3.92 and M3.5. I have been recording earthquakes down to M2.4 (in
that range) on my station. I have so far seen 5 - 6 earthquakes from
this swarm, that is at distance of approx 188 - 192 km away from me.
Regards.
--
Jón Frímann
http://www.jonfr.com
http://www.simnet.is/jonfr500/earthquake/
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: RE: Seismograph for school
From: "Stephen Hammond" shammon1@.............
Date: Tue, 26 Sep 2006 10:38:03 -0700
Hi, I would like to add a few thoughts. There are some simple plans on the
PSN San Jose website. http://pw2.netcom.com/~shammon1/equip.htm#Plans
however, I strongly suggest that you look at Larry's WINSDR software /
equipment because in the classroom, the software environment is one of the
most important attributes you need to consider. The stability of the system
hardware and software and the quality of the information provided
significantly improves the students interaction and learning outcome from
using the system. For example, if you look at the PSN San Jose main page
http://www.PublicSeismicNetwork.com you will find two links at the bottom
left of the page to South Valley Middle School and Los Altos High School.
Both schools are using WINSDR and Larry's hardware. Initially when we built
the system at Los Altos we provided a PC, sensors and simple amp. At South
Valley, Jan Froom went though several steps getting to the current system
configuration you see today. With the evolution of the Internet, there is a
real need to incorporate the seismic data into the classroom websites. This
simplifies the teachers interaction with the system and helps to generate
significant student/parent interest in the project. As you can see from the
examples, by using the automatic upload feature of Larry's WINSDR, the
sensor data is uploaded continuously during the 24 hour period. Another
benefit is the amount of interest the system generates outside of the
classroom. Look back at the Los Alto page and you will see there have been
over 24,000 trips to Greg Stoehr's seismic science page at Los Altos High in
the last two years. Considering that he has about 300 students per semester,
this provides a 40-trip / student page access ratio which is a significant
amount of return on investment. Greg keeps the system in his classroom and
his students take part in operating the system during the class year. Greg
is extremely limited on the amount of time he can spend on the system and
WINSDR has significantly improved his productivity. With a minimal
investment, you will see a vast improvement over a simple classroom sensor
and amp.
Regards, Steve Hammond PSN San Jose, Aptos California
-----Original Message-----
From: psn-l-request@.............. [mailto:psn-l-request@.................
Behalf Of tchannel
Sent: Tuesday, September 26, 2006 7:38 AM
To: psn-l@..............
Subject: Re: Seismograph for school
Hi John, Ted here, and I am one month into a similar project, using my
own money, for a non profit organization.
We are having a lot of fun on the project, but the electronics are
challenging, even though I have worked on circuits, I thought I was up to it
electronic task, but now I am not sure. I have made some progress however,
so I think I am getting closer.
I am happy to share my successes and failures if you would like to
correspond. Ted
----- Original Message -----
From: John Patskan
To: psn-l@..............
Sent: Monday, September 25, 2006 11:11 PM
Subject: Re: Seismograph for school
Hello everyone,
Thanks for the tips.
I believe I will try to build the Lehaman style unit.
This is actually an elementary school. It used to be an Environmental
Science magnet school, and they still have room they call the Eco-Lab. Each
class goes in there once a week and the teachers have them work on some
project. This year the teachers decided on a Geology theme. I thought a
seismograph would be nice to have in the lab. Actually I think the homemade
one would be better because the kids could get a better idea of how it
works. They wouldn't be doing anything in depth but I thought seeing there
own siesmograph records may spark some interest in science. I Haven't
approached the teachers yet as I want to make sure I can pull it off first.
John P
On 9/23/06, tchannel
wrote:
Hi Chris, What sort of "choice of suspension system" would you
recommend? Is there a detail I can look at?
I have only seen the knife edge style.
Thanks, Ted
----- Original Message -----
From: ChrisAtUpw@.......
To: psn-l@..............
Sent: Saturday, September 23, 2006 5:09 PM
Subject: Re: Seismograph for school
In a message dated 23/09/2006, jcpatskan@......... writes:
I am thinking of trying to build a seismograph for my son's
school. I have quite a bit of experience in shallow exploration geophysic's,
mostly electrical and electromagnetic, but none in seismology. I have
searched the internet and found quite a few resources.
Hi John,
You might consider making a medium sized Lehman - about 2 ft
long? Say about 1.5 sec period that can be extended to 20 sec?
You will need +/-12V stabilised power supplies of you may buy an
amplifier and transformer from Larry at http://psn.quake.net
Since it will be used with other school systems, I suggest that
you use Amaseis and buy a DI-154 12 bit ADC still at just $39! www.dataq.com
Amaseis supports this ADC.
See http://jclahr.com/science/psn/as1/index.html
Use magnetic damping, NOT oil.
Use an all metal braced single unit costruction - NO plastic
structural components - NO separated sections.
Your choice of suspension system is critical. NEITHER a point on
a plane NOR knife edge systems are satisfactory - avoid them like the
plague. Most other systems are OK to good. You need to be able to get a
period of at least 20 seconds.
Have a look at
http://jclahr.com/science/psn/chapman/lehman/index.html
and http://jclahr.com/science/psn/chapman/index.html
and http://www.jclahr.com/science/psn/cor_psn.html
and http://jclahr.com/science/psn/
ALSO
http://www.mgm.monschau.de/seismic/english/artikel/artikel_1_4.php and
sequels
I have also noticed a seismograph (or strong motion
accelerometer) on sale at e-bay, with an opening bid of $75.
I suggest that you forget this one! You do not need a strong
motion sensor - or the headaches of converting an optical one. This might be
called 'buying trouble'!
Good Luck!
Chris Chapman
Hi, I=20
would like to add a few thoughts. There are some simple plans on the PSN =
San=20
Jose website. http://pw2.netco=
m.com/~shammon1/equip.htm#Plans
however, I strongly suggest that you look at Larry's WINSDR =
software /=20
equipment because in the classroom, the software environment is one of =
the most=20
important attributes you need to consider. The stability of=20
the system hardware and software and the quality of the information =
provided=20
significantly improves the students interaction and learning outcome =
from=20
using the system. For example, if you look at the PSN San Jose main =
page http://www.PublicSeismicNet=
work.com you=20
will find two links at the bottom left of the page to South Valley =
Middle=20
School and Los Altos High School. Both schools are using WINSDR and =
Larry's=20
hardware. Initially when we built the system at Los Altos we =
provided a PC,=20
sensors and simple amp. At South Valley, Jan Froom went though several =
steps=20
getting to the current system configuration you see today. With=20
the evolution of the Internet, there is a real need to incorporate =
the=20
seismic data into the classroom websites. This simplifies the teachers=20
interaction with the system and helps to generate significant =
student/parent=20
interest in the project. As you can see from the examples, by using the=20
automatic upload feature of Larry's WINSDR, the sensor data is uploaded=20
continuously during the 24 hour period. Another benefit is the amount of =
interest the system generates outside of the classroom. Look back at the =
Los=20
Alto page and you will see there have been over 24,000 trips to =
Greg=20
Stoehr's seismic science page at Los Altos High in the last two years.=20
Considering that he has about 300 students per semester, this provides a =
40-trip=20
/ student page access ratio which is a significant amount of return =
on=20
investment. Greg keeps the system in his classroom and his students =
take=20
part in operating the system during the class year. Greg is extremely =
limited on=20
the amount of time he can spend on the system and WINSDR has =
significantly=20
improved his productivity. With a minimal investment, you will see a =
vast=20
improvement over a simple classroom sensor and amp.
Regards, Steve Hammond PSN San Jose, Aptos=20
California
Hi John, Ted here, and I am one =
month into=20
a similar project, using my own money, for a non profit=20
organization.
We are having a lot of fun on the =
project, but=20
the electronics are challenging, even though I have worked on =
circuits, I=20
thought I was up to it electronic task, but now I am not =
sure. I=20
have made some progress however, so I think I am getting =
closer.
I am happy to share my successes and =
failures if=20
you would like to correspond. Ted
----- Original Message -----
From:=20
John=20
Patskan
Sent: Monday, September 25, =
2006 11:11=20
PM
Subject: Re: Seismograph for=20
school
Hello everyone,
Thanks for the tips.
I =
believe=20
I will try to build the Lehaman style unit.
This is actually =
an=20
elementary school. It used to be an Environmental Science =
magnet=20
school, and they still have room they call the Eco-Lab. Each =
class=20
goes in there once a week and the teachers have them work on some =
project.=20
This year the teachers decided on a Geology theme. I =
thought a=20
seismograph would be nice to have in the lab. Actually I think =
the=20
homemade one would be better because the kids could get a better =
idea of how=20
it works. They wouldn't be doing anything in depth but I =
thought=20
seeing there own siesmograph records may spark some interest in =
science.=20
I Haven't approached the teachers yet as I want to make sure I =
can=20
pull it off first.
John P
On 9/23/06, tchannel <tchannel@..............>=20
wrote:=20
Hi Chris, What sort of "choice of suspension system" =
would you=20
recommend? Is there a detail I can look at?
I have only seen the knife edge style.
Thanks, Ted
----- Original Message ----- =
From: ChrisAtUpw@.......=20
Sent: Saturday, =
September 23,=20
2006 5:09 PM
Subject: Re: =
Seismograph for=20
school
In a message dated 23/09/2006,
jcpatskan@............
writes:
Hi John,
You might consider making a medium =
sized=20
Lehman - about 2 ft long? Say about 1.5 sec period that can be =
extended=20
to 20 sec?
You will need +/-12V stabilised =
power=20
supplies of you may buy an amplifier and transformer from Larry =
at
http://psn.quake.net
Since it will be used with other =
school=20
systems, I suggest that you use =
Amaseis and buy a=20
DI-154 12 bit ADC
still at just $39! =
www.dataq.com =
Amaseis=20
supports this ADC. See
http://jclahr.com/science/psn/as1/index.html
Use magnetic damping, NOT oil.
Use an all metal braced single unit =
costruction - NO plastic structural components - NO separated=20
sections.
Your choice of suspension system is =
critical.=20
NEITHER a point on a plane NOR knife edge systems are =
satisfactory -=20
avoid them like the plague. Most other systems are OK to good. =
You need=20
to be able to get a period of at least 20 seconds.
Have a look at
http://jclahr.com/science/psn/chapman/lehman/index.html=20
and
http://jclahr.com/science/psn/chapman/index.html
and
http://www.jclahr.com/science/psn/cor_psn.html and
http://jclahr.com/science/psn/
ALSO
http://www.mgm.monschau.de/seismic/english/artikel/artike=
l_1_4.php=20
and sequels
I have also =
noticed a=20
seismograph (or strong motion accelerometer) =
on sale=20
at e-bay, with an opening bid of $75.
I suggest that you=20
forget this one! You do not need a strong =
motion=20
sensor - or the headaches of converting an optical one. This =
might be=20
called 'buying trouble'!
Good Luck!
Chris Chapman
=
Subject: Earthquake swarm
From: =?ISO-8859-1?Q?J=F3n_Fr=EDmann?= jonfr500@.........
Date: Tue, 26 Sep 2006 16:13:43 +0000
Hi all
There is a earthquake swarm going on in the Bardarbungu volcano fissure
system. So far ~125 earthquakes have been recorded, two largest onces
where M3.92 and M3.5. I have been recording earthquakes down to M2.4 (in
that range) on my station. I have so far seen 5 - 6 earthquakes from
this swarm, that is at distance of approx 188 - 192 km away from me.
Regards.
--
Jón Frímann
http://www.jonfr.com
http://www.simnet.is/jonfr500/earthquake/
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Seismograph for school
From: "tchannel" tchannel@..............
Date: Tue, 26 Sep 2006 19:20:13 -0600
Hi Stephen, Thanks for this recommended site...I could not enlarge the =
PSN Preamp and PSN filter Amp by Pete Rowe, to see the values on the =
drawings. I searched the net but could not find any other site for =
them. Do you know where I might be abe to find these, large enough to =
print? Thanks, Ted
----- Original Message -----=20
From: Stephen Hammond=20
To: psn-l@.................
Sent: Tuesday, September 26, 2006 11:38 AM
Subject: RE: Seismograph for school
Hi, I would like to add a few thoughts. There are some simple plans on =
the PSN San Jose website. =
http://pw2.netcom.com/~shammon1/equip.htm#Plans
however, I strongly suggest that you look at Larry's WINSDR software / =
equipment because in the classroom, the software environment is one of =
the most important attributes you need to consider. The stability of the =
system hardware and software and the quality of the information provided =
significantly improves the students interaction and learning outcome =
from using the system. For example, if you look at the PSN San Jose main =
page http://www.PublicSeismicNetwork.com you will find two links at the =
bottom left of the page to South Valley Middle School and Los Altos High =
School. Both schools are using WINSDR and Larry's hardware. Initially =
when we built the system at Los Altos we provided a PC, sensors and =
simple amp. At South Valley, Jan Froom went though several steps getting =
to the current system configuration you see today. With the evolution of =
the Internet, there is a real need to incorporate the seismic data into =
the classroom websites. This simplifies the teachers interaction with =
the system and helps to generate significant student/parent interest in =
the project. As you can see from the examples, by using the automatic =
upload feature of Larry's WINSDR, the sensor data is uploaded =
continuously during the 24 hour period. Another benefit is the amount of =
interest the system generates outside of the classroom. Look back at the =
Los Alto page and you will see there have been over 24,000 trips to Greg =
Stoehr's seismic science page at Los Altos High in the last two years. =
Considering that he has about 300 students per semester, this provides a =
40-trip / student page access ratio which is a significant amount of =
return on investment. Greg keeps the system in his classroom and his =
students take part in operating the system during the class year. Greg =
is extremely limited on the amount of time he can spend on the system =
and WINSDR has significantly improved his productivity. With a minimal =
investment, you will see a vast improvement over a simple classroom =
sensor and amp.=20
Regards, Steve Hammond PSN San Jose, Aptos California=20
-----Original Message-----
From: psn-l-request@.............. =
[mailto:psn-l-request@................. Behalf Of tchannel
Sent: Tuesday, September 26, 2006 7:38 AM
To: psn-l@..............
Subject: Re: Seismograph for school
Hi John, Ted here, and I am one month into a similar project, using =
my own money, for a non profit organization.
We are having a lot of fun on the project, but the electronics are =
challenging, even though I have worked on circuits, I thought I was up =
to it electronic task, but now I am not sure. I have made some =
progress however, so I think I am getting closer.
I am happy to share my successes and failures if you would like to =
correspond. Ted
----- Original Message -----=20
From: John Patskan=20
To: psn-l@.................
Sent: Monday, September 25, 2006 11:11 PM
Subject: Re: Seismograph for school
Hello everyone,
Thanks for the tips.
I believe I will try to build the Lehaman style unit.
This is actually an elementary school. It used to be an =
Environmental Science magnet school, and they still have room they call =
the Eco-Lab. Each class goes in there once a week and the teachers have =
them work on some project. This year the teachers decided on a Geology =
theme. I thought a seismograph would be nice to have in the lab. =
Actually I think the homemade one would be better because the kids could =
get a better idea of how it works. They wouldn't be doing anything in =
depth but I thought seeing there own siesmograph records may spark some =
interest in science. I Haven't approached the teachers yet as I want to =
make sure I can pull it off first.=20
John P
On 9/23/06, tchannel
wrote:=20
Hi Chris, What sort of "choice of suspension system" would you =
recommend? Is there a detail I can look at?=20
I have only seen the knife edge style.=20
Thanks, Ted
----- Original Message -----=20
From: ChrisAtUpw@..........
To: psn-l@.................
Sent: Saturday, September 23, 2006 5:09 PM
Subject: Re: Seismograph for school=20
In a message dated 23/09/2006, jcpatskan@......... writes:
I am thinking of trying to build a seismograph for my son's =
school. I have quite a bit of experience in shallow exploration =
geophysic's, mostly electrical and electromagnetic, but none in =
seismology. I have searched the internet and found quite a few =
resources.=20
Hi John,
You might consider making a medium sized Lehman - about 2 =
ft long? Say about 1.5 sec period that can be extended to 20 sec?
You will need +/-12V stabilised power supplies of you may =
buy an amplifier and transformer from Larry at http://psn.quake.net
Since it will be used with other school systems, I suggest =
that you use Amaseis and buy a DI-154 12 bit ADC still at just $39! =
www.dataq.com Amaseis supports this ADC.=20
See http://jclahr.com/science/psn/as1/index.html
Use magnetic damping, NOT oil.=20
Use an all metal braced single unit costruction - NO =
plastic structural components - NO separated sections.
Your choice of suspension system is critical. NEITHER a =
point on a plane NOR knife edge systems are satisfactory - avoid them =
like the plague. Most other systems are OK to good. You need to be able =
to get a period of at least 20 seconds.=20
Have a look at =
http://jclahr.com/science/psn/chapman/lehman/index.html=20
and http://jclahr.com/science/psn/chapman/index.html
and http://www.jclahr.com/science/psn/cor_psn.html
and http://jclahr.com/science/psn/
ALSO =
http://www.mgm.monschau.de/seismic/english/artikel/artikel_1_4.php and =
sequels
I have also noticed a seismograph (or strong motion =
accelerometer) on sale at e-bay, with an opening bid of $75. =20
I suggest that you forget this one! You do not need a =
strong motion sensor - or the headaches of converting an optical one. =
This might be called 'buying trouble'!
Good Luck!
Chris Chapman
Hi Stephen, Thanks for this =
recommended=20
site...I could not enlarge the PSN Preamp and PSN filter Amp by Pete =
Rowe, to=20
see the values on the drawings. I searched the net but could not =
find any=20
other site for them. Do you know where I might be abe to find =
these, large=20
enough to print? Thanks, Ted
----- Original Message -----
From:=20
Stephen=20
Hammond
Sent: Tuesday, September 26, =
2006 11:38=20
AM
Subject: RE: Seismograph for =
school
Hi,=20
I would like to add a few thoughts. There are some simple plans on the =
PSN San=20
Jose website. http://pw2.netco=
m.com/~shammon1/equip.htm#Plans
however, I strongly suggest that you look at Larry's WINSDR =
software /=20
equipment because in the classroom, the software environment is one of =
the=20
most important attributes you need to consider. The stability=20
of the system hardware and software and the quality of the information =
provided significantly improves the students interaction and learning =
outcome=20
from using the system. For example, if you look at the PSN San =
Jose main=20
page http://www.PublicSeismicNet=
work.com you=20
will find two links at the bottom left of the page to South =
Valley Middle=20
School and Los Altos High School. Both schools are using WINSDR and =
Larry's=20
hardware. Initially when we built the system at Los Altos we =
provided a=20
PC, sensors and simple amp. At South Valley, Jan Froom went though =
several=20
steps getting to the current system configuration you see =
today. With=20
the evolution of the Internet, there is a real need to =
incorporate the=20
seismic data into the classroom websites. This simplifies the teachers =
interaction with the system and helps to generate significant =
student/parent=20
interest in the project. As you can see from the examples, by using =
the=20
automatic upload feature of Larry's WINSDR, the sensor data is =
uploaded=20
continuously during the 24 hour period. Another benefit is the amount =
of=20
interest the system generates outside of the classroom. Look back at =
the Los=20
Alto page and you will see there have been over 24,000 trips to =
Greg=20
Stoehr's seismic science page at Los Altos High in the last two years. =
Considering that he has about 300 students per semester, this provides =
a=20
40-trip / student page access ratio which is a significant amount =
of=20
return on investment. Greg keeps the system in his classroom and =
his=20
students take part in operating the system during the class year. Greg =
is=20
extremely limited on the amount of time he can spend on the system and =
WINSDR=20
has significantly improved his productivity. With a minimal =
investment, you=20
will see a vast improvement over a simple classroom sensor and amp.=20
Regards, Steve Hammond PSN San Jose, Aptos=20
California
Hi John, Ted here, and I am =
one month=20
into a similar project, using my own money, for a non profit=20
organization.
We are having a lot of fun on the =
project, but=20
the electronics are challenging, even though I have worked on =
circuits, I=20
thought I was up to it electronic task, but now I am not =
sure. I=20
have made some progress however, so I think I am getting=20
closer.
I am happy to share my successes =
and failures=20
if you would like to correspond. Ted
----- Original Message ----- =
From:=20
John=20
Patskan
Sent: Monday, September 25, =
2006=20
11:11 PM
Subject: Re: Seismograph =
for=20
school
Hello everyone,
Thanks for the =
tips.
I=20
believe I will try to build the Lehaman style unit.
This is =
actually an elementary school. It used to be an =
Environmental=20
Science magnet school, and they still have room they call the =
Eco-Lab.=20
Each class goes in there once a week and the teachers have =
them work=20
on some project. This year the teachers decided on a Geology =
theme.=20
I thought a seismograph would be nice to have in the lab.=20
Actually I think the homemade one would be better because =
the kids=20
could get a better idea of how it works. They wouldn't be =
doing=20
anything in depth but I thought seeing there own siesmograph =
records may=20
spark some interest in science. I Haven't approached the =
teachers=20
yet as I want to make sure I can pull it off first.
John =
P
On 9/23/06, tchannel <tchannel@..............>=20
wrote:=20
Hi Chris, What sort of "choice of suspension system" =
would=20
you recommend? Is there a detail I can look at?
I have only seen the knife edge style.
Thanks, Ted
----- Original Message =
-----
From: ChrisAtUpw@.......=20
Sent: Saturday, =
September 23,=20
2006 5:09 PM
Subject: Re: =
Seismograph for=20
school
In a message dated 23/09/2006,
jcpatskan@............
writes:
Hi John,
You might consider making a =
medium sized=20
Lehman - about 2 ft long? Say about 1.5 sec period that can be =
extended to 20 sec?
You will need +/-12V stabilised =
power=20
supplies of you may buy an amplifier and transformer from =
Larry at
http://psn.quake.net
Since it will be used with other =
school=20
systems, I suggest that you use =
Amaseis and buy=20
a DI-154 12 bit ADC
still at just $39! =
www.dataq.com Amaseis=20
supports this ADC. See
http://jclahr.com/science/psn/as1/index.html
Use magnetic damping, NOT oil.
Use an all metal braced single =
unit=20
costruction - NO plastic structural components - NO separated=20
sections.
Your choice of suspension system is =
critical.=20
NEITHER a point on a plane NOR knife edge systems are =
satisfactory -=20
avoid them like the plague. Most other systems are OK to good. =
You=20
need to be able to get a period of at least 20 seconds.
Have a look at
http://jclahr.com/science/psn/chapman/lehman/index.html=20
and
http://jclahr.com/science/psn/chapman/index.html
and
http://www.jclahr.com/science/psn/cor_psn.html and
http://jclahr.com/science/psn/
ALSO
http://www.mgm.monschau.de/seismic/english/artikel/artike=
l_1_4.php=20
and sequels
I have also =
noticed a=20
=
seismograph (or strong motion accelerometer) on=20
sale at e-bay, with an opening bid of $75. =
I suggest that you=20
forget this one! You do not need a =
strong motion=20
sensor - or the headaches of converting an optical one. This =
might be=20
called 'buying trouble'!
Good Luck!
Chris Chapman
=
Subject: Re: Seismograph for school
From: "Geoffrey" gmvoeth@...........
Date: Tue, 26 Sep 2006 18:36:25 -0700
I think if you search the sites for ZIP files
you may find they contain the images you are seeking.
I noticed that the design might work better
if you can somehow reverse the positions
of the damper and main sensor.
The sensor should really be located on the tip
of the lever for maximum mechanical amplification
of velocity.
But i think you should shoot for the vertical
version of this same kind of model.
Regards;
geoff
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Seismograph for school
From: Pete Rowe ptrowe@.........
Date: Tue, 26 Sep 2006 21:30:10 -0700 (PDT)
Ted
I'll be glad to send you PDF files of my schematics.
Let me know
Pete Rowe
San Jose, CA
ptrowe@.........
--- tchannel
wrote:
> Hi Stephen, Thanks for this recommended site...I
> could not enlarge the PSN Preamp and PSN filter Amp
> by Pete Rowe, to see the values on the drawings. I
> searched the net but could not find any other site
> for them. Do you know where I might be abe to find
> these, large enough to print? Thanks, Ted
> ----- Original Message -----
> From: Stephen Hammond
> To: psn-l@..............
> Sent: Tuesday, September 26, 2006 11:38 AM
> Subject: RE: Seismograph for school
>
>
> Hi, I would like to add a few thoughts. There are
> some simple plans on the PSN San Jose website.
> http://pw2.netcom.com/~shammon1/equip.htm#Plans
> however, I strongly suggest that you look at
> Larry's WINSDR software / equipment because in the
> classroom, the software environment is one of the
> most important attributes you need to consider. The
> stability of the system hardware and software and
> the quality of the information provided
> significantly improves the students interaction and
> learning outcome from using the system. For example,
> if you look at the PSN San Jose main page
> http://www.PublicSeismicNetwork.com you will find
> two links at the bottom left of the page to South
> Valley Middle School and Los Altos High School. Both
> schools are using WINSDR and Larry's hardware.
> Initially when we built the system at Los Altos we
> provided a PC, sensors and simple amp. At South
> Valley, Jan Froom went though several steps getting
> to the current system configuration you see today.
> With the evolution of the Internet, there is a real
> need to incorporate the seismic data into the
> classroom websites. This simplifies the teachers
> interaction with the system and helps to generate
> significant student/parent interest in the project.
> As you can see from the examples, by using the
> automatic upload feature of Larry's WINSDR, the
> sensor data is uploaded continuously during the 24
> hour period. Another benefit is the amount of
> interest the system generates outside of the
> classroom. Look back at the Los Alto page and you
> will see there have been over 24,000 trips to Greg
> Stoehr's seismic science page at Los Altos High in
> the last two years. Considering that he has about
> 300 students per semester, this provides a 40-trip /
> student page access ratio which is a significant
> amount of return on investment. Greg keeps the
> system in his classroom and his students take part
> in operating the system during the class year. Greg
> is extremely limited on the amount of time he can
> spend on the system and WINSDR has significantly
> improved his productivity. With a minimal
> investment, you will see a vast improvement over a
> simple classroom sensor and amp.
> Regards, Steve Hammond PSN San Jose, Aptos
> California
>
> -----Original Message-----
> From: psn-l-request@..............
> [mailto:psn-l-request@................. Behalf Of
> tchannel
> Sent: Tuesday, September 26, 2006 7:38 AM
> To: psn-l@..............
> Subject: Re: Seismograph for school
>
>
> Hi John, Ted here, and I am one month into a
> similar project, using my own money, for a non
> profit organization.
> We are having a lot of fun on the project, but
> the electronics are challenging, even though I have
> worked on circuits, I thought I was up to it
> electronic task, but now I am not sure. I have
> made some progress however, so I think I am getting
> closer.
> I am happy to share my successes and failures if
> you would like to correspond. Ted
> ----- Original Message -----
> From: John Patskan
> To: psn-l@..............
> Sent: Monday, September 25, 2006 11:11 PM
> Subject: Re: Seismograph for school
>
>
> Hello everyone,
>
> Thanks for the tips.
>
> I believe I will try to build the Lehaman
> style unit.
>
> This is actually an elementary school. It
> used to be an Environmental Science magnet school,
> and they still have room they call the Eco-Lab.
> Each class goes in there once a week and the
> teachers have them work on some project. This year
> the teachers decided on a Geology theme. I thought
> a seismograph would be nice to have in the lab.
> Actually I think the homemade one would be better
> because the kids could get a better idea of how it
> works. They wouldn't be doing anything in depth but
> I thought seeing there own siesmograph records may
> spark some interest in science. I Haven't
> approached the teachers yet as I want to make sure I
> can pull it off first.
>
> John P
>
>
> On 9/23/06, tchannel
> wrote:
> Hi Chris, What sort of "choice of
> suspension system" would you recommend? Is there a
> detail I can look at?
> I have only seen the knife edge style.
> Thanks, Ted
> ----- Original Message -----
> From: ChrisAtUpw@.......
> To: psn-l@..............
> Sent: Saturday, September 23, 2006 5:09 PM
> Subject: Re: Seismograph for school
>
>
> In a message dated 23/09/2006,
> jcpatskan@......... writes:
> I am thinking of trying to build a
> seismograph for my son's school. I have quite a bit
> of experience in shallow exploration geophysic's,
> mostly electrical and electromagnetic, but none in
> seismology. I have searched the internet and found
> quite a few resources.
> Hi John,
>
> You might consider making a medium
> sized Lehman - about 2 ft long? Say about 1.5 sec
> period that can be extended to 20 sec?
>
> You will need +/-12V stabilised power
> supplies of you may buy an amplifier and transformer
> from Larry at http://psn.quake.net
>
> Since it will be used with other
> school systems, I suggest that you use Amaseis and
> buy a DI-154 12 bit ADC still at just $39!
> www.dataq.com Amaseis supports this ADC.
> See
> http://jclahr.com/science/psn/as1/index.html
>
> Use magnetic damping, NOT oil.
>
> Use an all metal braced single unit
> costruction - NO plastic structural components - NO
> separated sections.
>
> Your choice of suspension system is
> critical. NEITHER a point on a plane NOR knife edge
> systems are satisfactory - avoid them like the
> plague. Most other systems are OK to good. You need
> to be able to get a period of at least 20 seconds.
>
> Have a look at
>
http://jclahr.com/science/psn/chapman/lehman/index.html
>
> and
> http://jclahr.com/science/psn/chapman/index.html
> and
> http://www.jclahr.com/science/psn/cor_psn.html
> and http://jclahr.com/science/psn/
>
> ALSO
>
http://www.mgm.monschau.de/seismic/english/artikel/artikel_1_4.php
> and sequels
>
> I have also noticed a seismograph (or
> strong motion accelerometer) on sale at e-bay, with
> an opening bid of $75.
> I suggest that you forget this one!
> You do not need a strong motion sensor - or the
> headaches of converting an optical one. This might
> be called 'buying trouble'!
>
> Good Luck!
>
> Chris Chapman
>
>
>
__________________________________________________
Do You Yahoo!?
Tired of spam? Yahoo! Mail has the best spam protection around
http://mail.yahoo.com
__________________________________________________________
Public Seismic Network Mailing List (PSN-L)
Subject: Re: Seismograph for school
From: John or Jan Lahr JohnJan@........
Date: Tue, 26 Sep 2006 21:56:42 -0700
Ted,
Larry Cochrane has given me permission to post his seismic
amplifier/circuit, which is a well designed and proven to work well.
http://jclahr.com/science/psn/cochrane/
The easiest route is to purchase one from Larry:
http://psn.quake.net/eqamp.html
A simpler design is posted here:
http://jclahr.com/science/psn/amp_filt/
John
At 06:20 PM 9/26/2006, you wrote:
Hi Stephen,
Thanks for this recommended site...I could not enlarge the PSN Preamp and
PSN filter Amp by Pete Rowe, to see the values on the drawings. I
searched the net but could not find any other site for them. Do you
know where I might be abe to find these, large enough to print?
Thanks, Ted
Subject: RE: Seismograph for school
From: "Stephen Hammond" shammon1@.............
Date: Wed, 27 Sep 2006 09:20:37 -0700
Hi Pete, Ted, Chris, others-- I'll defer to Pete Rowe as he is the circuit
designer of the original PSN amp that I use in my system with Larry's serial
data collection board and WINSDR and as he can send you the PDF of his
original handout I'll defer to him. BTW, this is the drawing that served as
the source for the machine drawings on my site. Pete, if you would, please
send a copy of the PDF to me at the adders below. I'll add it to my PSN San
Jose site. Thanks--
I also received a couple of notes from Chris Chapman (thanks Chris) that
have some details that I was not aware of and you may not have seen. So,
here is that text. " There is now a network of school sites all over the USA
on SpiNet and on some sites outside. There are two in the UK and this is
expected to increase very significantly in the next couple of years. See
www.scieds.com/spinet for details. They all use a free recording program
called Amaseis and AboutTime time clock updates. For details see the Iris
website under 'outreach' or http://jclahr.com/science/psn/as1/index.html.
Amaseis does support Dataq ADCs and their DI-154 12 bit +/-10V model is now
reduced in price to $39 + pp. www.dataq.com This is about the minimum
resolution which is useful for seismic recording. The same resolution is
used on the school AS-1 seismometers, distributed by Iris. "
Chris also shared a link to John Lahr's web page with a sensor picture I had
not seen http://jclahr.com/science/psn/chapman/lehman/index.html and I can
only be described it as "very cool" and I want two...
Regards, Steve Hammond PSN San Jose, Aptos California
shammon1@.............
-----Original Message-----
From: psn-l-request@..............
[mailto:psn-l-request@................. Behalf Of Pete Rowe
Sent: Tuesday, September 26, 2006 9:30 PM
To: psn-l@..............
Subject: Re: Seismograph for school
Ted
I'll be glad to send you PDF files of my schematics.
Let me know
Pete Rowe
San Jose, CA
ptrowe@.........
--- tchannel wrote:
> Hi Stephen, Thanks for this recommended site...I
> could not enlarge the PSN Preamp and PSN filter Amp
> by Pete Rowe, to see the values on the drawings. I
> searched the net but could not find any other site
> for them. Do you know where I might be abe to find
> these, large enough to print? Thanks, Ted
> ----- Original Message -----
> From: Stephen Hammond
> To: psn-l@..............
> Sent: Tuesday, September 26, 2006 11:38 AM
> Subject: RE: Seismograph for school
>
>
> Hi, I would like to add a few thoughts. There are
> some simple plans on the PSN San Jose website.
> http://pw2.netcom.com/~shammon1/equip.htm#Plans
> however, I strongly suggest that you look at
> Larry's WINSDR software / equipment because in the
> classroom, the software environment is one of the
> most important attributes you need to consider. The
> stability of the system hardware and software and
> the quality of the information provided
> significantly improves the students interaction and
> learning outcome from using the system. For example,
> if you look at the PSN San Jose main page
> http://www.PublicSeismicNetwork.com you will find
> two links at the bottom left of the page to South
> Valley Middle School and Los Altos High School. Both
> schools are using WINSDR and Larry's hardware.
> Initially when we built the system at Los Altos we
> provided a PC, sensors and simple amp. At South
> Valley, Jan Froom went though several steps getting
> to the current system configuration you see today.
> With the evolution of the Internet, there is a real
> need to incorporate the seismic data into the
> classroom websites. This simplifies the teachers
> interaction with the system and helps to generate
> significant student/parent interest in the project.
> As you can see from the examples, by using the
> automatic upload feature of Larry's WINSDR, the
> sensor data is uploaded continuously during the 24
> hour period. Another benefit is the amount of
> interest the system generates outside of the
> classroom. Look back at the Los Alto page and you
> will see there have been over 24,000 trips to Greg
> Stoehr's seismic science page at Los Altos High in
> the last two years. Considering that he has about
> 300 students per semester, this provides a 40-trip /
> student page access ratio which is a significant
> amount of return on investment. Greg keeps the
> system in his classroom and his students take part
> in operating the system during the class year. Greg
> is extremely limited on the amount of time he can
> spend on the system and WINSDR has significantly
> improved his productivity. With a minimal
> investment, you will see a vast improvement over a
> simple classroom sensor and amp.
> Regards, Steve Hammond PSN San Jose, Aptos
> California
>
> -----Original Message-----
> From: psn-l-request@..............
> [mailto:psn-l-request@................. Behalf Of
> tchannel
> Sent: Tuesday, September 26, 2006 7:38 AM
> To: psn-l@..............
> Subject: Re: Seismograph for school
>
>
> Hi John, Ted here, and I am one month into a
> similar project, using my own money, for a non
> profit organization.
> We are having a lot of fun on the project, but
> the electronics are challenging, even though I have
> worked on circuits, I thought I was up to it
> electronic task, but now I am not sure. I have
> made some progress however, so I think I am getting
> closer.
> I am happy to share my successes and failures if
> you would like to correspond. Ted
> ----- Original Message -----
> From: John Patskan
> To: psn-l@..............
> Sent: Monday, September 25, 2006 11:11 PM
> Subject: Re: Seismograph for school
>
>
> Hello everyone,
>
> Thanks for the tips.
>
> I believe I will try to build the Lehaman
> style unit.
>
> This is actually an elementary school. It
> used to be an Environmental Science magnet school,
> and they still have room they call the Eco-Lab.
> Each class goes in there once a week and the
> teachers have them work on some project. This year
> the teachers decided on a Geology theme. I thought
> a seismograph would be nice to have in the lab.
> Actually I think the homemade one would be better
> because the kids could get a better idea of how it
> works. They wouldn't be doing anything in depth but
> I thought seeing there own siesmograph records may
> spark some interest in science. I Haven't
> approached the teachers yet as I want to make sure I
> can pull it off first.
>
> John P
>
>
> On 9/23/06, tchannel
> wrote:
> Hi Chris, What sort of "choice of
> suspension system" would you recommend? Is there a
> detail I can look at?
> I have only seen the knife edge style.
> Thanks, Ted
> ----- Original Message -----
> From: ChrisAtUpw@.......
> To: psn-l@..............
> Sent: Saturday, September 23, 2006 5:09 PM
> Subject: Re: Seismograph for school
>
>
> In a message dated 23/09/2006,
> jcpatskan@......... writes:
> I am thinking of trying to build a
> seismograph for my son's school. I have quite a bit
> of experience in shallow exploration geophysic's,
> mostly electrical and electromagnetic, but none in
> seismology. I have searched the internet and found
> quite a few resources.
> Hi John,
>
> You might consider making a medium
> sized Lehman - about 2 ft long? Say about 1.5 sec
> period that can be extended to 20 sec?
>
> You will need +/-12V stabilised power
> supplies of you may buy an amplifier and transformer
> from Larry at http://psn.quake.net
>
> Since it will be used with other
> school systems, I suggest that you use Amaseis and
> buy a DI-154 12 bit ADC still at just $39!
> www.dataq.com Amaseis supports this ADC.
> See
> http://jclahr.com/science/psn/as1/index.html
>
> Use magnetic damping, NOT oil.
>
> Use an all metal braced single unit
> costruction - NO plastic structural components - NO
> separated sections.
>
> Your choice of suspension system is
> critical. NEITHER a point on a plane NOR knife edge
> systems are satisfactory - avoid them like the
> plague. Most other systems are OK to good. You need
> to be able to get a period of at least 20 seconds.
>
> Have a look at
>
http://jclahr.com/science/psn/chapman/lehman/index.html
>
> and
> http://jclahr.com/science/psn/chapman/index.html
> and
> http://www.jclahr.com/science/psn/cor_psn.html
> and http://jclahr.com/science/psn/
>
> ALSO
>
http://www.mgm.monschau.de/seismic/english/artikel/artikel_1_4.php
> and sequels
>
> I have also noticed a seismograph (or
> strong motion accelerometer) on sale at e-bay, with
> an opening bid of $75.
> I suggest that you forget this one!
> You do not need a strong motion sensor - or the
> headaches of converting an optical one. This might
> be called 'buying trouble'!
>
> Good Luck!
>
> Chris Chapman
>
>
>
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Subject: Re: Seismograph for school
From: "Geoffrey" gmvoeth@...........
Date: Wed, 27 Sep 2006 10:23:48 -0700
A suggestion only and a few observations:
You can also design and build your own using basic circuits that are well known in the radio (ARRL) community because frequency
seems to have no effect in results provided you can find the right components to meet your needs. There are free softwares out there
to help you do this. You just need to have some basic curiosity above the level of playing follow the leader. I hate to think that
amateures are so single minded as to be unwilling to dabble in fields other than geology. Some things are fixed and proven and for
those ideas just buy kits and modify them to your needs. Homebuilt sensors lack uniformity so the related electronics must be
flexable to accomidate the differences. If you are forced to buy premade equipment to use in combination with third party sensors I
think your results will be less than desirable. Only if you buy the entire system between sensor and recorder including the sensor
do i accept what results.
I will not accept copy rights for things like op amp circutry or computer programs because there exists more than just one way to
arrive at given results. Two different peoples can arrive at the very same through in independent research and unlike the law I
would damn no one for such results. Whatever works for you is alright by me as an amateur seeking only knowledge.
Please teach your kids to think for themselves and have an imagination in resolving problems.
Americas imagination seems to have been sold to other places
and i just do not see good imaginations anymore in our society.
But then I have never imagined anything myself that I believe to be original, it seems I can never top those who came before me. All
I can do is mix and match in artistic ways to get what i want some of the time.
What we really need is a standard system that can be thoroughly understood for Amateurs whatever field so that the field can have a
kind of uniformity. You go into the field and buy the standard system then you can experiment on the side to improve results if at
all possible.
But as far as I know no group of GeoPhysicist have agreed on any kind of standards for us.
The peoples who take an interest in us are more than likely only security peoples keeping a close eye on potential renagade
sciences. Or potential Entrepreneuers trying to make money.
There seems to be an effort on the part of security minded peoples to destroy or keep disorganized any groups that have not arisen
through formal education and/or have no leadership.
Also that thing called religion is the ancient enemy of science.
We must all be on our guard for novel ways to destroy us.
You must teach your kids more than just the sciences to really know the discipline.
Regards;
geoff
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Public Seismic Network Mailing List (PSN-L)
Subject: Re: Seismograph for school
From: "tchannel" tchannel@..............
Date: Thu, 28 Sep 2006 16:55:54 -0600
Hi John and Others, We all heard about the 6.7 SAMOA ISLANDS REGION at =
28 Sep 2006 06:22:11. After checking my station first thing this =
morning, "Like a kid on Christmas morning" I saw a signal, or what I =
hoped was a signal. I checked the internet and found this 6.7, was in =
the same time area. I was able to expand my trace and look for the P =
and S......I use local Helicorder and PSN's from the net so I could look =
for similar parts of the event, not really knowing where to start. My =
station is primitive but I am improving it everyday. Working on a new =
Amp and Filter. If someone has some free time to correspond with me on =
this issue, please email me and I can send screenshots of what I did and =
where I think the P and S are. I am a bit confused because the P look =
like the same time it should have arrived, in Boise, but what I think =
is the S is too early. Where the S should be, I don't see it. I don't =
wish to bother the group, but if someone would like to help me, I would =
be grateful. Anyhow I think I recorded my first Earthquake.
My wife was not nearly as impressed, as I was.
Thanks, Ted
----- Original Message -----=20
From: John or Jan Lahr=20
To: psn-l@.................
Sent: Tuesday, September 26, 2006 10:56 PM
Subject: Re: Seismograph for school
Ted,
Larry Cochrane has given me permission to post his seismic =
amplifier/circuit, which is a well designed and proven to work well.
http://jclahr.com/science/psn/cochrane/
The easiest route is to purchase one from Larry: =
http://psn.quake.net/eqamp.html
A simpler design is posted here:
http://jclahr.com/science/psn/amp_filt/
John
At 06:20 PM 9/26/2006, you wrote:
Hi Stephen, Thanks for this recommended site...I could not enlarge =
the PSN Preamp and PSN filter Amp by Pete Rowe, to see the values on the =
drawings. I searched the net but could not find any other site for =
them. Do you know where I might be abe to find these, large enough to =
print? Thanks, Ted
Hi John and Others, We all heard =
about the=20
6.7 SAMOA ISLANDS REGION at 28 Sep 2006 06:22:11. After checking =
my=20
station first thing this morning, "Like a kid on Christmas morning" I =
saw a=20
signal, or what I hoped was a signal. I checked the internet =
and=20
found this 6.7, was in the same time area. I was able to =
expand my=20
trace and look for the P and S......I use local Helicorder and PSN's =
from the=20
net so I could look for similar parts of the event, not really knowing =
where to=20
start. My station is primitive but I am improving it =
everyday. =20
Working on a new Amp and Filter. If someone has some free =
time to=20
correspond with me on this issue, please email me and I can send =
screenshots of=20
what I did and where I think the P and S are. I am a bit =
confused=20
because the P look like the same time it should have arrived, in Boise,=20
but what I think is the S is too early. Where the S should =
be, I=20
don't see it. I don't wish to bother the group, but if =
someone would=20
like to help me, I would be grateful. Anyhow I think I recorded my =
first=20
Earthquake.
My wife was not nearly as impressed, as =
I=20
was.
Thanks, Ted
----- Original Message -----
From:=20
John or =
Jan Lahr=20
Sent: Tuesday, September 26, =
2006 10:56=20
PM
Subject: Re: Seismograph for =
school
Ted,
Larry Cochrane has given me permission to =
post his=20
seismic amplifier/circuit, which is a well designed and proven to work =
well.
http://jclahr.com/science/psn/cochrane/
The =
easiest=20
route is to purchase one from Larry: http://psn.quake.net/eqamp.html
A =
simpler design=20
is posted here:
http://jclahr.com/science/psn/amp_filt/
Joh=
n
At=20
06:20 PM 9/26/2006, you wrote:
Hi =
Stephen, =20
Thanks for this recommended site...I could not enlarge the PSN =
Preamp and=20
PSN filter Amp by Pete Rowe, to see the values on the =
drawings. I=20
searched the net but could not find any other site for them. =
Do you=20
know where I might be abe to find these, large enough to =
print? =20
Thanks, Ted
Subject: Re: Seismograph for school
From: "tchannel" tchannel@..............
Date: Fri, 29 Sep 2006 12:07:14 -0600
Hi Pete, I have started the boards,
1. Is the 5k pot a trim for gain?
2. What is the 50k pot "offset" for and when and how is it tweaked.
3. The C4, 4.4uF or 2.2 par.x2 are to be Non-polar, is this
Non-polarized? or the type without the +and - on the can.
I have 2.2uF I think non-polarized, If these work would I place the - toward
ground? I could not find Ceramic.
4. On the .018uF could I sub .02uF?
5. On the 1.5uF could I sub 1.47uF
I understand sometimes these value are critical, and sometimes not. If any
of them are ratio (as an example like this) Fc=1/6.2832x R1xC1 I could
adj the R's easier then the C's
Thanks, Ted
----- Original Message -----
From: "Pete Rowe"
To:
Sent: Tuesday, September 26, 2006 10:30 PM
Subject: Re: Seismograph for school
> Ted
> I'll be glad to send you PDF files of my schematics.
> Let me know
> Pete Rowe
> San Jose, CA
> ptrowe@.........
>
> --- tchannel wrote:
>
>> Hi Stephen, Thanks for this recommended site...I
>> could not enlarge the PSN Preamp and PSN filter Amp
>> by Pete Rowe, to see the values on the drawings. I
>> searched the net but could not find any other site
>> for them. Do you know where I might be abe to find
>> these, large enough to print? Thanks, Ted
>> ----- Original Message -----
>> From: Stephen Hammond
>> To: psn-l@..............
>> Sent: Tuesday, September 26, 2006 11:38 AM
>> Subject: RE: Seismograph for school
>>
>>
>> Hi, I would like to add a few thoughts. There are
>> some simple plans on the PSN San Jose website.
>> http://pw2.netcom.com/~shammon1/equip.htm#Plans
>> however, I strongly suggest that you look at
>> Larry's WINSDR software / equipment because in the
>> classroom, the software environment is one of the
>> most important attributes you need to consider. The
>> stability of the system hardware and software and
>> the quality of the information provided
>> significantly improves the students interaction and
>> learning outcome from using the system. For example,
>> if you look at the PSN San Jose main page
>> http://www.PublicSeismicNetwork.com you will find
>> two links at the bottom left of the page to South
>> Valley Middle School and Los Altos High School. Both
>> schools are using WINSDR and Larry's hardware.
>> Initially when we built the system at Los Altos we
>> provided a PC, sensors and simple amp. At South
>> Valley, Jan Froom went though several steps getting
>> to the current system configuration you see today.
>> With the evolution of the Internet, there is a real
>> need to incorporate the seismic data into the
>> classroom websites. This simplifies the teachers
>> interaction with the system and helps to generate
>> significant student/parent interest in the project.
>> As you can see from the examples, by using the
>> automatic upload feature of Larry's WINSDR, the
>> sensor data is uploaded continuously during the 24
>> hour period. Another benefit is the amount of
>> interest the system generates outside of the
>> classroom. Look back at the Los Alto page and you
>> will see there have been over 24,000 trips to Greg
>> Stoehr's seismic science page at Los Altos High in
>> the last two years. Considering that he has about
>> 300 students per semester, this provides a 40-trip /
>> student page access ratio which is a significant
>> amount of return on investment. Greg keeps the
>> system in his classroom and his students take part
>> in operating the system during the class year. Greg
>> is extremely limited on the amount of time he can
>> spend on the system and WINSDR has significantly
>> improved his productivity. With a minimal
>> investment, you will see a vast improvement over a
>> simple classroom sensor and amp.
>> Regards, Steve Hammond PSN San Jose, Aptos
>> California
>>
>> -----Original Message-----
>> From: psn-l-request@..............
>> [mailto:psn-l-request@................. Behalf Of
>> tchannel
>> Sent: Tuesday, September 26, 2006 7:38 AM
>> To: psn-l@..............
>> Subject: Re: Seismograph for school
>>
>>
>> Hi John, Ted here, and I am one month into a
>> similar project, using my own money, for a non
>> profit organization.
>> We are having a lot of fun on the project, but
>> the electronics are challenging, even though I have
>> worked on circuits, I thought I was up to it
>> electronic task, but now I am not sure. I have
>> made some progress however, so I think I am getting
>> closer.
>> I am happy to share my successes and failures if
>> you would like to correspond. Ted
>> ----- Original Message -----
>> From: John Patskan
>> To: psn-l@..............
>> Sent: Monday, September 25, 2006 11:11 PM
>> Subject: Re: Seismograph for school
>>
>>
>> Hello everyone,
>>
>> Thanks for the tips.
>>
>> I believe I will try to build the Lehaman
>> style unit.
>>
>> This is actually an elementary school. It
>> used to be an Environmental Science magnet school,
>> and they still have room they call the Eco-Lab.
>> Each class goes in there once a week and the
>> teachers have them work on some project. This year
>> the teachers decided on a Geology theme. I thought
>> a seismograph would be nice to have in the lab.
>> Actually I think the homemade one would be better
>> because the kids could get a better idea of how it
>> works. They wouldn't be doing anything in depth but
>> I thought seeing there own siesmograph records may
>> spark some interest in science. I Haven't
>> approached the teachers yet as I want to make sure I
>> can pull it off first.
>>
>> John P
>>
>>
>> On 9/23/06, tchannel
>> wrote:
>> Hi Chris, What sort of "choice of
>> suspension system" would you recommend? Is there a
>> detail I can look at?
>> I have only seen the knife edge style.
>> Thanks, Ted
>> ----- Original Message -----
>> From: ChrisAtUpw@.......
>> To: psn-l@..............
>> Sent: Saturday, September 23, 2006 5:09 PM
>> Subject: Re: Seismograph for school
>>
>>
>> In a message dated 23/09/2006,
>> jcpatskan@......... writes:
>> I am thinking of trying to build a
>> seismograph for my son's school. I have quite a bit
>> of experience in shallow exploration geophysic's,
>> mostly electrical and electromagnetic, but none in
>> seismology. I have searched the internet and found
>> quite a few resources.
>> Hi John,
>>
>> You might consider making a medium
>> sized Lehman - about 2 ft long? Say about 1.5 sec
>> period that can be extended to 20 sec?
>>
>> You will need +/-12V stabilised power
>> supplies of you may buy an amplifier and transformer
>> from Larry at http://psn.quake.net
>>
>> Since it will be used with other
>> school systems, I suggest that you use Amaseis and
>> buy a DI-154 12 bit ADC still at just $39!
>> www.dataq.com Amaseis supports this ADC.
>> See
>> http://jclahr.com/science/psn/as1/index.html
>>
>> Use magnetic damping, NOT oil.
>>
>> Use an all metal braced single unit
>> costruction - NO plastic structural components - NO
>> separated sections.
>>
>> Your choice of suspension system is
>> critical. NEITHER a point on a plane NOR knife edge
>> systems are satisfactory - avoid them like the
>> plague. Most other systems are OK to good. You need
>> to be able to get a period of at least 20 seconds.
>>
>> Have a look at
>>
> http://jclahr.com/science/psn/chapman/lehman/index.html
>>
>> and
>> http://jclahr.com/science/psn/chapman/index.html
>> and
>> http://www.jclahr.com/science/psn/cor_psn.html
>> and http://jclahr.com/science/psn/
>>
>> ALSO
>>
> http://www.mgm.monschau.de/seismic/english/artikel/artikel_1_4.php
>> and sequels
>>
>> I have also noticed a seismograph (or
>> strong motion accelerometer) on sale at e-bay, with
>> an opening bid of $75.
>> I suggest that you forget this one!
>> You do not need a strong motion sensor - or the
>> headaches of converting an optical one. This might
>> be called 'buying trouble'!
>>
>> Good Luck!
>>
>> Chris Chapman
>>
>>
>>
>
>
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