From: Karl Cunningham Subject: Re: VBB feedback current Date: Tue, 30 Jun 1998 14:57:34 -0700 Sean-Thomas -- Thanks for all the information. I think I understand what you are saying about the feedback generating a current in the coil. It seems that if an amplifier has a low input impedance (to impersonate the impedance of the feedback coil), and if its output is a current from a high-impedance source (to impersonate the high impedance of the feedback components), I don't see why it wouldn't work. In other words, if one could place an ideal CURRENT amplifier in the line to the feedback coil, to magically boost the current to the coil while keeping everything else the same, would that not work? If so, then the problem is only to construct such a device. (And there are a lot of ways to connect up an op-amp). Since G of my new vertical will be about 4.7 (N/A-kg), I am planning to experiment with a current amplifier. And I am interested in methods to verify that the response is as desired. Please understand that I mean no disrespect, and I realize that you have a LOT more experience with seismic instrumentation than I do. But being one of those head-in-the-clouds engineer types who thinks that most of the world's problems can be solved with op-amps, I tend to question things I think I understand but don't make sense to me. (And I'd be even more of a pain if I were from Missouri ;). Karl Cunningham La Mesa, CA. PSN station #40 karlc@....... _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: John Hernlund Subject: Re: Nuclear? tests? Date: Tue, 30 Jun 1998 17:34:36 -0700 (MST) On Tue, 30 Jun 1998, robert barns wrote: > Has solid evidence been presented that the Indian and/or Pakistani > "nuclear" tests were really nuclear events and not just large explosions of > conventional explosives? > Bob Barns Yes, they were nuclear. I am ashamed to admit that I can't remember who it was that posted some really cool EMPs recorded using some other device... ****************************************************************************** John Hernlund E-mail: hernlund@....... WWW: http://www.mc.maricopa.edu/academic/phy_sci/Geology/hernlund/ http://www.public.asu.edu/~hernlund/ "Enlightenment is man's emergence from his self-imposed immaturity. Immaturity is the inability to use one's understanding without guidance from another. This immaturity is self-imposed when its cause lies not in lack of understanding, but in lack of resolve and courage to use it without guidance from another. Sapere Aude! "Have courage to use your own understanding!"- that is the motto of enlightenment. -Immanuel Kant: "An Answer to the Question: What is Enlightenment?" ****************************************************************************** _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: barry lotz Subject: Re: S-G period and Q Date: Tue, 30 Jun 1998 18:09:25 -0700 Hi Ed That's the way I understand it also. Barry Edward Cranswick wrote: > > Barry- > Having been forced to examine textbooks ("Mechanics", Symon; "Physics", > Resnick & Halliday) from physics classes I failed, I think that your > statements below confirm my belief that the frequency of a simple pendulum is > independent of its mass for all angles. Please correct me if I am wrong. > -Edward > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: frankcnd@.......... (Frank Condon) Subject: Re: Nuclear? tests? Date: Tue, 30 Jun 1998 21:22:14 -0700 (PDT) Hi Guys: It was Charlie Plyler who captured those fantastic graphs with his ELF instrumentation. Yes, you can clearly see the EMP from the nuclear detonations. It is somewhat unclear as to how many indian tests were conducted from what is claimed. Frank Condon frankcnd@.......... "Located in the seismic corridor somewhere between Fontana & Mammoth Lakes" >On Tue, 30 Jun 1998, robert barns wrote: >> Has solid evidence been presented that the Indian and/or Pakistani >> "nuclear" tests were really nuclear events and not just large explosions of >> conventional explosives? >> Bob Barns > > Yes, they were nuclear. I am ashamed to admit that I can't remember who it >was that posted some really cool EMPs recorded using some other device... > >****************************************************************************** > > John Hernlund > E-mail: hernlund@....... > WWW: http://www.mc.maricopa.edu/academic/phy_sci/Geology/hernlund/ > http://www.public.asu.edu/~hernlund/ > >"Enlightenment is man's emergence from his self-imposed immaturity. >Immaturity is the inability to use one's understanding without guidance from >another. This immaturity is self-imposed when its cause lies not in lack of >understanding, but in lack of resolve and courage to use it without guidance >from another. Sapere Aude! "Have courage to use your own understanding!"- >that is the motto of enlightenment. >-Immanuel Kant: "An Answer to the Question: What is Enlightenment?" > >****************************************************************************** > > >_____________________________________________________________________ > >Public Seismic Network Mailing List (PSN-L) > >To leave this list email listserver@............. with the body of the >message: leave PSN-L > > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Greg Subject: Re: Nuclear? tests? Date: Tue, 30 Jun 1998 21:50:48 -0700 Frank Condon wrote: > It was Charlie Plyler who captured those fantastic graphs with his ELF Unless he's an employee of the Pakistan government and he faked the images ;) Conspiracy theory anyone? Encrypting my hard disk right now, Greg _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Walt Williams" Subject: SETI SOHO -- CNN Report Date: Tue, 30 Jun 1998 23:41:21 +0000 ------- Forwarded Message Follows ------- From: "Walt Williams" To: seti@....... Date: Mon, 29 Jun 1998 22:32:52 +0000 Subject: SETI SOHO -- CNN Report Hello All, On 06-29-98, CNN (TV news 'channel'), after announcing Peter Sturrock's SSE 'UFO' scientific panel review and report, reported that "controllers lost contact with the Solar and Heliospheric Observatory" (SOHO) spacecraft. See: http://www.foxnews.com:80/js_index.sml?content=/scitech/062998/lostsat ellite.sml For information on the SOHO spacecraft see: http://wholesun.nascom.nasa.gov/index-text.html Walt Williams _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: robert barns <75612.2635@..............> Subject: Re: Nuclear? tests? Date: Wed, 1 Jul 1998 11:46:37 -0400 Hi, I have little knowledge about the production of EMP by nuclear tests bu= t I'm wondering if tests, esp. such small ones, produce EMP detectable at long distances. If so, would it have been enough for Plyler to detect? The 26 June issue of Science mag. and the July issue of Physics Today (which arrived yesterday) have extensive and very interesting technical articles about the tests. They both discuss seismic data in detail and conclude that the data conflict with many of the Indian and Pakistani claims. Neither mentions EMP observations. Hurry down to your library and look these up. Physics Today has other info. of interest to seismologists. Bob Barns Wear short sleeves! Support your right to bare arms! = _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: robert barns <75612.2635@..............> Subject: Re: Nuclear? tests? Date: Wed, 1 Jul 1998 11:46:37 -0400 Hi, I have little knowledge about the production of EMP by nuclear tests bu= t I'm wondering if tests, esp. such small ones, produce EMP detectable at long distances. If so, would it have been enough for Plyler to detect? The 26 June issue of Science mag. and the July issue of Physics Today (which arrived yesterday) have extensive and very interesting technical articles about the tests. They both discuss seismic data in detail and conclude that the data conflict with many of the Indian and Pakistani claims. Neither mentions EMP observations. Hurry down to your library and look these up. Physics Today has other info. of interest to seismologists. Bob Barns Wear short sleeves! Support your right to bare arms! = _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: John Hernlund Subject: Re: Nuclear? tests? Date: Wed, 01 Jul 1998 13:03:37 -0700 (MST) On Wed, 1 Jul 1998, robert barns wrote: > I have little knowledge about the production of EMP by nuclear tests but > I'm wondering if tests, esp. such small ones, produce EMP > detectable at long distances. Yes, they sure can... > If so, would it have been enough for Plyler to detect? I think so. The problem is how the pulse is going to find its way around the globe, i.e. how will it propagate... Many portions of the earth at great depth are far too conductive to allow short wavelength propagation (must be ultra-long period), so that leaves mainly ionospheric reflection for the vast majority of the energy, similar to the transmission of strong radio. Some frequencies from the pulse will probably not behave in this manner, but EMPs are a mess that always has a matching frequency. If I had that file of Charlie Plyer's I would be interested in looking at the fourier spectrum to see how low the frequencies reach... > Neither mentions EMP observations. EMP observations are probably too often forgot by the public, however I think that they are used a lot more than we know about...and they will not appear in scientific journals much because there isn't a whole lot of prospects for exploiting it scientifically... ****************************************************************************** John Hernlund E-mail: hernlund@....... WWW: http://www.mc.maricopa.edu/academic/phy_sci/Geology/hernlund/ http://www.public.asu.edu/~hernlund/ "Enlightenment is man's emergence from his self-imposed immaturity. Immaturity is the inability to use one's understanding without guidance from another. This immaturity is self-imposed when its cause lies not in lack of understanding, but in lack of resolve and courage to use it without guidance from another. Sapere Aude! "Have courage to use your own understanding!"- that is the motto of enlightenment. -Immanuel Kant: "An Answer to the Question: What is Enlightenment?" ****************************************************************************** _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Jim Hannon Subject: Re: Nuclear? tests? Date: Wed, 01 Jul 1998 19:31:13 -0500 John Hernlund wrote: > > EMP observations are probably too often forgot by the public, however I think > that they are used a lot more than we know about...and they will not appear in > scientific journals much because there isn't a whole lot of prospects for > exploiting it scientifically... > John, This is not exactly EMP but have you heard of project HAARP? A huge HF transmitter in Alaska that can beam energy up into the ionosphere to cause local heating of the ionosphere. By proper scanning of the HF beam they expect to be able to generate ELF waves in the ionosphere. One use of the generated ELF waves is imaging of underground features, Such as faults and nuclear test facilities. An experiment using naturally occuring ELF has imaged the tunnel in Texas for the defunct accelerator project. HAARP has generated huge amounts of protests against this supposed "directed energy weapon". -- Jim Hannon http://soli.inav.net/~jmhannon/ 42,11.90N 91,39.26W WB0TXL _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "David A. Nelson" Subject: Re: Nuclear? tests? Date: Thu, 02 Jul 1998 13:29:03 +1200 Yes Jim i know of it i recorded an excellect documentary about HAARP in late 1996 off the telly and as u say all about the out cries of a weapon weather control etc. very interesting all the same Dave >John, >This is not exactly EMP but have you heard of project HAARP? >A huge HF transmitter in Alaska that can beam energy up into the >ionosphere to cause local heating of the ionosphere. By proper scanning >of the HF beam they expect to be able to generate ELF waves in the >ionosphere. One use of the generated ELF waves is imaging of underground >features, Such as faults and nuclear test facilities. An experiment >using naturally occuring ELF has imaged the tunnel in Texas for the >defunct accelerator project. >HAARP has generated huge amounts of protests against this supposed >"directed energy weapon". >Jim Hannon Co-ordinator: New Zealand Public Seismic Network Dave A. Nelson ZL4TBN 24 Jensen St., Green Is., Dunedin, South Is.. New Zealand. http://psn.quake.net/dave/home.htm IF there indeed are other parallel universes... I can now rest in the knowledge, that in at least one of them, I am filthy rich and drive a red Ferrari _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "frank murray" Subject: RE: (Fwd) SETI SOHO -- CNN Report Date: Wed, 1 Jul 1998 19:02:11 -0700 > On 06-29-98, CNN (TV news 'channel'), after announcing Peter > Sturrock's SSE 'UFO' scientific panel review and report, > reported that "controllers lost contact with the Solar and > Heliospheric Observatory" (SOHO) spacecraft. yes...the second major satellite to go bonkers, since folks started getting noisy about clinton sending satellite encryption and control tech to the chicoms...kinda looks like they're sending us a message... let's see now, how'd that intro on "the outer limits" go: "WE control the horizontal", "WE control the vertical"... frank _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: frankcnd@.......... (Frank Condon) Subject: Stovepipe Wells M4.7 Ubehebe Crater Date: Wed, 1 Jul 1998 23:31:49 -0700 (PDT) Hello All: What is your opinion about the recent seismic activity right near the old Ubehebe Crater in Death Valley? The depth was very shallow and seem to be epicentered very close to the crater. What is the historic record for the Ubehebe crater? Anything happened there over the past 500 years? Frank Condon frankcnd@.......... "Located in the Seismic Corridor Somewhere Between Fontana & Mammoth Lakes" _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: watson@................ (Charles Watson) Subject: New Mammoth EQ site Date: Wed, 01 Jul 1998 23:42:10 -0700 Fellow earthquake chasers, The Mammoth Times nespaper has asked me to put together a Seismo-Watch Earthquake Report for their web site. Before I submit it to them, I would like your comments to the following web page(s): http://www.seismo-watch.com/EQSERVICES/SeismoReports/MTSeismo/MTSeismo.html I know the graphics are a bit bulky and I will improve the bit density as time goes on. I also used a new jpg compaction method which seems to work well with my browser but I am unsure how it will work with others. Feel free to make some constructive comments and either post them here or send them to me directly. -- ---/---- Charles P. Watson, Consulting Geologist Advanced Geologic Exploration/Seismo-Watch P.O. Box 18012, Reno, Nevada 89511 Voice: 702-852-0992 / Fax: 702-852-3226 mailto:watson@................ http://www.seismo-watch.com _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: watson@................ (Charles Watson) Subject: Re: Stovepipe Wells M4.7 Ubehebe Crater Date: Thu, 02 Jul 1998 00:00:29 -0700 Yea, I saw that too, Frank. A number of years ago, I mapped some of the active faults along the Death Valley-Furnace Creek fault system. Pretty impressive. Multiple displacements along a wide zone. I forget, but I think the Ubehebe Crater is on the west for the Cottenwood Mountains. There is a promintory ridge that comes down from Tin Mountain and the crater is off the northwest side. The DV-FC fault is on the east side of Death Valley, a few miles east from the Ubehebe Crater. There are a bunch of springs along the fault trace and that's where Scottys Castle is. The epicenter for the M4.7 looks like it is southwest of Scottys Castle near the defunct(?) Mesquite Spring. Mayby it'll start flowing again, eh? Kinda erie since the northern portion of the DV-FC fault in Fish Lake Valley had that M5.1 and subsequence robust swarm. Max credable eq for the DV-FC fault is ~M8. EeeeK! -- ---/---- Charles P. Watson Seismo-Watch _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Walt Williams" Subject: The Sun Did It! Date: Thu, 2 Jul 1998 02:06:56 +0000 Frank, Please forgive me, this is off topic, one last time. The first satellite I could 'see' a possible link, whereas the SOHO is research craft which was built by the ESA and NASA to study the sun. If one were to visit the SEL archive at: gopher://proton.sec.noaa.gov:70/I9/plots/satenv/980627 gopher://proton.sec.noaa.gov:70/I9/plots/electron/980627 Maybe the sun fried it? Walt, 98.07.02 ============================================ ------- Forwarded Message Follows ------- From: "frank murray" To: "PSN-L Mailing List" Subject: RE: (Fwd) SETI SOHO -- CNN Report Date: Wed, 1 Jul 1998 19:02:11 -0700 Reply-to: PSN-L Mailing List > On 06-29-98, CNN (TV news 'channel'), after announcing Peter > Sturrock's SSE 'UFO' scientific panel review and report, > reported that "controllers lost contact with the Solar and > Heliospheric Observatory" (SOHO) spacecraft. yes...the second major satellite to go bonkers, since folks started getting noisy about clinton sending satellite encryption and control tech to the chicoms...kinda looks like they're sending us a message... let's see now, how'd that intro on "the outer limits" go: "WE control the horizontal", "WE control the vertical"... frank _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: watson@................ (Charles Watson) Subject: Re: The Sun Did It! Date: Thu, 02 Jul 1998 07:42:25 -0700 I received a Solar bulletin which said the craft was lost at 23:16 GMT 24 June. The anomalies on the GEOS Sat were on June 26. Pretty strong anomalies, though. -- ---/---- Charles P. Watson Seismo-Watch Walt Williams wrote: > > Frank, > > Please forgive me, this is off topic, one last time. > > The first satellite I could 'see' a possible link, whereas the SOHO > is research craft which was built by the ESA and NASA to > study the sun. If one were to visit the SEL archive at: > > gopher://proton.sec.noaa.gov:70/I9/plots/satenv/980627 > gopher://proton.sec.noaa.gov:70/I9/plots/electron/980627 > > Maybe the sun fried it? > > Walt, 98.07.02 > ============================================ > > ------- Forwarded Message Follows ------- > From: "frank murray" > To: "PSN-L Mailing List" > Subject: RE: (Fwd) SETI SOHO -- CNN Report > Date: Wed, 1 Jul 1998 19:02:11 -0700 > Reply-to: PSN-L Mailing List > > > On 06-29-98, CNN (TV news 'channel'), after announcing Peter > > Sturrock's SSE 'UFO' scientific panel review and report, > > reported that "controllers lost contact with the Solar and > > Heliospheric Observatory" (SOHO) spacecraft. > > yes...the second major satellite to go bonkers, since folks started > getting noisy about clinton sending satellite encryption and control > tech to the chicoms...kinda looks like they're sending us a message... > > let's see now, how'd that intro on "the outer limits" go: "WE control > the horizontal", "WE control the vertical"... > > frank > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "frank murray" Subject: RE: New Mammoth EQ site Date: Thu, 2 Jul 1998 09:38:19 -0700 hi charlie, well organized site...date is prominent, an item too often ignored...graphics are both pleasant to eye and info-rich...but one very slight problem: the depth chart gives the viewer the first impression that the recent series of quakes are within the caldera...i'm not sure that can be avoided without excessive section views or explanatory notes that would clutter up the site... good job, frank > Fellow earthquake chasers, > > The Mammoth Times nespaper has asked me to put together a Seismo-Watch > Earthquake Report for their web site. Before I submit it to them, I > would like your comments to the following web page(s): > http://www.seismo-watch.com/EQSERVICES/SeismoReports/MTSeismo/MTSeismo.html I know the graphics are a bit bulky and I will improve the bit density as time goes on. I also used a new jpg compaction method which seems to work well with my browser but I am unsure how it will work with others. Feel free to make some constructive comments and either post them here or send them to me directly. -- ---/---- Charles P. Watson, Consulting Geologist Advanced Geologic Exploration/Seismo-Watch P.O. Box 18012, Reno, Nevada 89511 Voice: 702-852-0992 / Fax: 702-852-3226 mailto:watson@................ http://www.seismo-watch.com _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "frank murray" Subject: RE: The Sun Did It! Date: Thu, 2 Jul 1998 09:56:08 -0700 walt wrote: > The first satellite I could 'see' a possible link, whereas the SOHO > is research craft which was built by the ESA and NASA to > study the sun. If one were to visit the SEL archive at: i agree that this is a bit off topic here, but on the other hand, earth watchers are likely to be decently informed on other matters of scientific interest...so i pose the question: anybody here know a source for info on the control of the SOHO??...specifically, were those same encryption algoritms used in it??... btw...i'd have thought that nasa would have hardened the craft to protect against the maximum reasonably expected sun blasts... frank _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: watson@................ (Charles Watson) Subject: Re: New Mammoth EQ site Date: Thu, 02 Jul 1998 10:03:56 -0700 Thanks for your comments, Frank. Yea, unsure how to make the activity in the Sierra terrain stand out differently than that in the caldera without a north-south x-section. maybe if I get a couple more sponsors, I can spend the extra time in making one. (hint-hint) Thanks again!! -- ---/---- Charlie Seismo-Watch _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: lahr@.................. Subject: IASPEI Web Site Date: Thu, 2 Jul 1998 13:25:24 -0600 (MDT) The International Association of Seismology and Physics of the Earth's Interior (IASPEI) home page, located at http://www.seismo.com/iaspei/ may have some items of interest to PSN members, although I have not checked it out in depth. JCLahr ################################## John C. Lahr ################################# Seismologist ################################ U.S. Geological Survey ############################### Geologic Hazards Team, MS966 ############################## PO Box 25046 #############################/############################## ############################/############################### Denver, Colorado 80225-0046 ################################ Phone: (303) 273-8596 ################################## Fax: (303) 273-8600 ################################### lahr@........ ##################################### http://giseis.alaska.edu/lahr http://lahr.org/john-jan _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Walt Williams" Subject: PSNL - Re: Nuclear? tests? - HAARP Date: Thu, 2 Jul 1998 15:59:35 +0000 Hello, FYI. Regarding HAARP, there is much blah, blah, blah, but here is some of the good stuff. High-frequency Active Auroral Research Program (HAARP). Cut to the chase: Data Index: http://www.haarp.alaska.edu/haarp/data.html My favorite data: http://server5550.itd.nrl.navy.mil/projects/haarp/rioData.html (The 98 data seems to have disappeared?) HAARP Diagnostic: http://server5550.itd.nrl.navy.mil/projects/haarp/haarpDiag.html and the Main page: http://server5550.itd.nrl.navy.mil/projects/haarp/index.html Walt, 98.07.02 p.s. I am still working the problems of my Lehman seismometer. Flexure is a problem, now I think I know why everybody went with the short plate and the bricks. ========================================================== ------- Forwarded Message Follows ------- Date: Thu, 02 Jul 1998 13:29:03 +1200 To: PSN-L Mailing List From: "David A. Nelson" Subject: Re: Nuclear? tests? Reply-to: PSN-L Mailing List Yes Jim i know of it i recorded an excellect documentary about HAARP in late 1996 off the telly and as u say all about the out cries of a weapon weather control etc. very interesting all the same Dave >John, >This is not exactly EMP but have you heard of project HAARP? >A huge HF transmitter in Alaska that can beam energy up into the >ionosphere to cause local heating of the ionosphere. By proper scanning >of the HF beam they expect to be able to generate ELF waves in the >ionosphere. One use of the generated ELF waves is imaging of underground >features, Such as faults and nuclear test facilities. An experiment >using naturally occuring ELF has imaged the tunnel in Texas for the >defunct accelerator project. >HAARP has generated huge amounts of protests against this supposed >"directed energy weapon". >Jim Hannon Co-ordinator: New Zealand Public Seismic Network Dave A. Nelson ZL4TBN 24 Jensen St., Green Is., Dunedin, South Is.. New Zealand. http://psn.quake.net/dave/home.htm IF there indeed are other parallel universes... I can now rest in the knowledge, that in at least one of them, I am filthy rich and drive a red Ferrari _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: frankcnd@.......... (Frank Condon) Subject: Re: The Sun Did It! Date: Thu, 2 Jul 1998 16:59:25 -0700 (PDT) Hi Frank: Yeah, I think so too. That is a great possibility since we are having lots of CME's and proton streams headed towards us from the Sun. Thanks for the links! Unfortunately, I've heard that it will take a few years before they can replace it with another one. Frank >Frank, > >Please forgive me, this is off topic, one last time. > >The first satellite I could 'see' a possible link, whereas the SOHO >is research craft which was built by the ESA and NASA to >study the sun. If one were to visit the SEL archive at: > >gopher://proton.sec.noaa.gov:70/I9/plots/satenv/980627 >gopher://proton.sec.noaa.gov:70/I9/plots/electron/980627 > >Maybe the sun fried it? > >Walt, 98.07.02 >============================================ > > >------- Forwarded Message Follows ------- >From: "frank murray" >To: "PSN-L Mailing List" >Subject: RE: (Fwd) SETI SOHO -- CNN Report >Date: Wed, 1 Jul 1998 19:02:11 -0700 >Reply-to: PSN-L Mailing List > > > >> On 06-29-98, CNN (TV news 'channel'), after announcing Peter >> Sturrock's SSE 'UFO' scientific panel review and report, >> reported that "controllers lost contact with the Solar and >> Heliospheric Observatory" (SOHO) spacecraft. > >yes...the second major satellite to go bonkers, since folks started >getting noisy about clinton sending satellite encryption and control >tech to the chicoms...kinda looks like they're sending us a message... > >let's see now, how'd that intro on "the outer limits" go: "WE control >the horizontal", "WE control the vertical"... > >frank > > >_____________________________________________________________________ > >Public Seismic Network Mailing List (PSN-L) > >To leave this list email listserver@............. with the body of the >message: leave PSN-L > >_____________________________________________________________________ > >Public Seismic Network Mailing List (PSN-L) > >To leave this list email listserver@............. with the body of the >message: leave PSN-L > > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: S-T Morrissey Subject: VRDT calibration Date: Thu, 2 Jul 1998 19:59:57 -0500 (CDT) Meredith, You asked about calibrating the VRDT or displacement sensor for the VBB instrument, particularly the setup I use. It is quite basic, consisting of a heavy base plate to hold the fixed coils of the sensor, and a micrometer mounted so that the moving pin of the micrometer moves parallel to the baseplate. In reality, my baseplate is a large SS pressure cap from a deep ocean seis case, about 4" in diameter with a dozen holes drilled around the perimeter. I mount the coils frame of the VRDT in one of these holes. Then I use the mounting bracket of the micrometer to set it up so that it moves across the baseplate parallel to the VRDT frame, or at a right angle to the gap of the transducer. Then I use a strip of 1/4" wide by about 1/32" thick brass shim stock to attach the moving vane of the VRDT to the moving pin of the micrometer. The strip is simply wrapped in a tight short spiral around the 1/4" dia micrometer pin (actually, it is first wrapped around a thinner rod so it will fit tightly), with the free end turned 90 degrees and the ferrous vane attached (solder or epoxy) to it. By jointly pivoting the VRDT frame and the micrometer on the baseplate, they can be adjusted so that the vane fits perfectly centered in the VRDT coils gap and moves axially within it as the micrometer is turned. This is a case where a picture is worth ,......! But I think you can figure it out. I pre-set the vane position for a maximum positive output, then turn the micrometer in small increments (10 microns with the differential Mitutoyo unit I have) through zero to the maximum negative output. I do this at the PC, so I can log the numbers (voltage at each setting) as I do it. I reverse the procedure to repeat the data set. This results in the inverted V style plot of the web page. The slightly snakey appearance of the data wrt the straight line is due to the differential thread error of the micrometer for each revolution. A similar procedure can also be used with the SG capacitive sensor, but I would leave it assembled to the boom. The micrometer could be fastened to the base so that it pushes the boom or mass as it is turned, with a small rubber band making sure that constant contact is made. On the STM vertical, the micrometer can be fastened to the central support post such that it pushes up on the boom as it is turned. If you don't have a micrometer, the space between the boom and the support post can be filled with a stack of 0.001" shim stock strips until the VRDT output is at zero, then one strip at a time can be removed or added to calibrate the displacement transducer. You also asked about the pressure case for the STM. I did buy a 20 gallon terrarium and was fitting a reinforced acryllic lid to it with a feed-through for the electrical ribbon cable through the plastic frame. But the project is on hold because I was invited to show the STM seismometer to the IRIS Education and Outreach Committee at the IRIS workshop at Santa Cruz next week. So I decided to build three "neat and tidy" copies of the second prototype, and to take the better two, one as an assembled instrument, and another to show details of the individual parts. But the first task though was to complete the mechanical drawing of the complete instrument, which required taking all the dimensions from the Beta prototype and spending lots of time using CAD to make an accurate scaled drawing of the whole unit. I am making the three new units from the dimensional information of the drawing, which, of course, brings out all the errors so I can correct them. After I am done and all the corrections are made, I will post it on the web. It is accurate enough to be scaled up with a copier to full scale to make patterns for cutting and drilling. (I will put a 1/2 scale version in the SASE you sent several months ago.) And of course, improvements are still being made, like a modification of the spring suspension that allows quite long mechanical periods (over 20 seconds). Regards, Sean-THomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: EarthQuake Subject: Re: The Sun Did It! Date: Thu, 02 Jul 1998 19:03:09 -0700 At 04:59 PM 7/2/98 -0700, Frank Condon wrote: >Hi Frank: >Yeah, I think so too. That is a great possibility since we are having lots >of CME's and proton streams headed towards us from the Sun. Thanks for the >links! This has been ongoing for years.........so why is it now just coming up as a possibility? I and others have suggested that this may be science........probable...repeatable etc...........yet we continue to call the 'fringe' group of folks eccentric????? Hello? Good Morning! Of course Frank this is nothing personal...I jsust took it as a jumping off point for myown ventures.......Always appreciate your input! As well as most of Larry group. Bob PS Yes I know this is a group message! _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Walt Williams" Subject: PSN-L Re: The Sun Did It! Date: Thu, 2 Jul 1998 19:08:52 +0000 Charles, Thanks. Since I posted the e-letter to the PSN-L I have been in touch with a SOHO team member. They are hoping to regain control of the spacecraft; not looking too good. The sun as most already know has been quite anomalous, lately. Walt, 98.07.02 dfheli@.............. http://www.pacificnet.net/~dfheli ------- Forwarded Message Follows ------- Date: Thu, 02 Jul 1998 07:42:25 -0700 From: watson@................ (Charles Watson) Organization: Advanced Geologic Exploration / Seismo-Watch To: PSN-L Mailing List Subject: Re: The Sun Did It! Reply-to: PSN-L Mailing List I received a Solar bulletin which said the craft was lost at 23:16 GMT 24 June. The anomalies on the GEOS Sat were on June 26. Pretty strong anomalies, though. -- ---/---- Charles P. Watson Seismo-Watch Walt Williams wrote: > > Frank, > > Please forgive me, this is off topic, one last time. > > The first satellite I could 'see' a possible link, whereas the SOHO > is research craft which was built by the ESA and NASA to > study the sun. If one were to visit the SEL archive at: > > gopher://proton.sec.noaa.gov:70/I9/plots/satenv/980627 > gopher://proton.sec.noaa.gov:70/I9/plots/electron/980627 > > Maybe the sun fried it? > > Walt, 98.07.02 > ============================================ > > ------- Forwarded Message Follows ------- > From: "frank murray" > To: "PSN-L Mailing List" > Subject: RE: (Fwd) SETI SOHO -- CNN Report > Date: Wed, 1 Jul 1998 19:02:11 -0700 > Reply-to: PSN-L Mailing List > > > On 06-29-98, CNN (TV news 'channel'), after announcing Peter > > Sturrock's SSE 'UFO' scientific panel review and report, > > reported that "controllers lost contact with the Solar and > > Heliospheric Observatory" (SOHO) spacecraft. > > yes...the second major satellite to go bonkers, since folks started > getting noisy about clinton sending satellite encryption and control > tech to the chicoms...kinda looks like they're sending us a message... > > let's see now, how'd that intro on "the outer limits" go: "WE control > the horizontal", "WE control the vertical"... > > frank > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: John Hernlund Subject: Re: New Mammoth EQ site Date: Thu, 02 Jul 1998 20:03:22 -0700 (MST) On Thu, 2 Jul 1998, Charles Watson wrote: > Thanks for your comments, Frank. Yea, unsure how to make the activity in > the Sierra terrain stand out differently than that in the caldera > without a north-south x-section. maybe if I get a couple more sponsors, > I can spend the extra time in making one. (hint-hint) Charles, Jonathan Lees at Yale has developed some cool software that makes viewing and constructing seismic activity cross-sections easy...you can download it from his page (I don't have the address right now but it shouldn't be difficult to find). ****************************************************************************** John Hernlund E-mail: hernlund@....... WWW: http://www.mc.maricopa.edu/academic/phy_sci/Geology/hernlund/ http://www.public.asu.edu/~hernlund/ "Enlightenment is man's emergence from his self-imposed immaturity. Immaturity is the inability to use one's understanding without guidance from another. This immaturity is self-imposed when its cause lies not in lack of understanding, but in lack of resolve and courage to use it without guidance from another. Sapere Aude! "Have courage to use your own understanding!"- that is the motto of enlightenment. -Immanuel Kant: "An Answer to the Question: What is Enlightenment?" ****************************************************************************** _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: meredith lamb Subject: STM-8 new spring suspension and etc. Date: Thu, 02 Jul 1998 23:13:30 -0600 Sean-Thomas, Thanks for the detailed reply about the vrdt calibration, it all sounds good and clear too me. On the terrarium pressure case, with the acrylic lid, I presume you plan to have the lid on top/vertical? Probably the case weight was a factor along with the structurally weaker lid and its atmospheric pressure distribution along the top rim, away from the seismo. May need an anti-slide mechanism for the adjusting screws on the glass? We'll be looking forward to the new drawings of the STM-8 on the web. Actually, I'am glad I didn't start on the beta prototype mechanically, as any changes will be in the drawing and I'd have been out of date. Will the spring suspension improvement of over 20 seconds, be incorporated into the drawing; or is it too new thus far? That would be really something.....over 20 seconds....wow! Of course you know you've got to get that "published" fast-ha. Curiosity....I presume it changes the flexures; and, is it more or less stable than the old design, or is it yet to be made, or any other data? So....with the + 20 seconds, does this extend the vbb range significantly from 600 seconds upwards too? Boom the same length? Hope the IRIS workshop (etc.) goes very well, and they bestow alot of notoriety to your very significant contributions. Of course, I hope its very enjoyable there too. Have a good trip. Thanks, Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: frankcnd@.......... (Frank Condon) Subject: Re: New Mammoth EQ site Date: Thu, 2 Jul 1998 22:44:44 -0700 (PDT) Hello: Here is the URL for the software: http://love.geology.yale.edu/~lees/lees.html#lees.software Frank Condon frankcnd@.......... "Located in the seismic corridor somewhere between fontana & Mammoth Lakes" >On Thu, 2 Jul 1998, Charles Watson wrote: >> Thanks for your comments, Frank. Yea, unsure how to make the activity in >> the Sierra terrain stand out differently than that in the caldera >> without a north-south x-section. maybe if I get a couple more sponsors, >> I can spend the extra time in making one. (hint-hint) > >Charles, > Jonathan Lees at Yale has developed some cool software that makes viewing >and constructing seismic activity cross-sections easy...you can download it >from his page (I don't have the address right now but it shouldn't be >difficult to find). > >****************************************************************************** > > John Hernlund > E-mail: hernlund@....... > WWW: http://www.mc.maricopa.edu/academic/phy_sci/Geology/hernlund/ > http://www.public.asu.edu/~hernlund/ > >"Enlightenment is man's emergence from his self-imposed immaturity. >Immaturity is the inability to use one's understanding without guidance from >another. This immaturity is self-imposed when its cause lies not in lack of >understanding, but in lack of resolve and courage to use it without guidance >from another. Sapere Aude! "Have courage to use your own understanding!"- >that is the motto of enlightenment. >-Immanuel Kant: "An Answer to the Question: What is Enlightenment?" > >****************************************************************************** _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: watson@................ (Charles Watson) Subject: Re: New Mammoth EQ site Date: Thu, 02 Jul 1998 23:36:59 -0700 Wooh-golly Frank! That's some mean 3-D GIS software! Now that I have had the chance to wipe the drool from my chin, I'll have to break out the ATM card and treat myself to a SUN Sparcstations running SUN OS-4.1.3. Gads! In my dreams! Hey, if you got another lying around, I'll pay the shipping. :> I'll keep the URL for when my ship does come in. Thanks! Nevertheless, I should show a N-S x-section. My modest Mac software can handle the data, it just takes time to generate it, which is a valuable commodity these days when there are other mountains to climb. Cheers! -- ---/---- Charlie Forever chained to a vintage Mac Performa. Frank Condon wrote: > > Hello: > Here is the URL for the software: > http://love.geology.yale.edu/~lees/lees.html#lees.software > > Frank Condon > frankcnd@.......... > "Located in the seismic corridor somewhere between fontana & Mammoth Lakes" > > >On Thu, 2 Jul 1998, Charles Watson wrote: > >> Thanks for your comments, Frank. Yea, unsure how to make the activity in > >> the Sierra terrain stand out differently than that in the caldera > >> without a north-south x-section. maybe if I get a couple more sponsors, > >> I can spend the extra time in making one. (hint-hint) > > > >Charles, > > Jonathan Lees at Yale has developed some cool software that makes viewing > >and constructing seismic activity cross-sections easy...you can download it > >from his page (I don't have the address right now but it shouldn't be > >difficult to find). > > > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Greg Subject: Re: New Mammoth EQ site Date: Fri, 03 Jul 1998 09:15:17 -0700 Charles Watson wrote: > Wooh-golly Frank! That's some mean 3-D GIS software! Now that I have had the > chance to wipe the drool from my chin, I'll have to break out the ATM card and > treat myself to a SUN Sparcstations running SUN OS-4.1.3. Gads! In my dreams! The documentation page says, "The source code will be available in the future for easy porting to any X11 UNIX environment." Which probably means that with some effort you could get it to run under Linux. I have no idea how difficult it would be and I'm not anxious to try, becuase I have no need for it, but if you really wanted it... Linux for the Mac is a lot cheaper than a Sun (even a used Sun). Worst case scenario you have to prod some other people into helping you compile it for Mac Linux and you need a little more RAM/HD space to run Linux and MacOS on the same computer. If not, I've seen used (remanufactured) Sun workstations and servers on the onsale web site for well under $10,000 ;) A $4,000 dual Pentium II would probably be just as fast but oh well. Just a thought, Greg _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: angel Rodriguez Subject: Can this gizmo work? Date: Fri, 03 Jul 1998 12:36:22 -0400 Members of the list, I live and play in Panama (8,47 N by 82,41 W) and just lately have gotten interesed in this wonderful hobby. I have a vertical instrument that works well and am building several others. I keep time by reading the output of a handheld GPS. The other morning I made a gizmo and posted its photo on http://www.chiriqui.com/photo It's a 10k jpg. It's basically a horizontal device with a vertical pendulum but could easly be a Lehman type. The hinge is a piezo element that I took out of a broken phone. With my voltmeter I get quite a range of +- millivolt even with the slightest motion. My question is: Is this use of a piezo out to lunch? Has it been done and not proven useful? I don't want to waste my time, but if I can build useful cheap devices, why not. Any comment would be very welcome. Angel Rodriguez _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: watson@................ (Charles Watson) Subject: Re: New Mammoth EQ site Date: Fri, 03 Jul 1998 13:49:46 -0700 Thanks for the suggestions. I saw the line for Linux but had never known what it was. I would like to first upgrade my work station with a new Apple G-3 300 Mhz and from there expand back into the PC platform, with a UNIX machine operating all the core data retrevial and processing. As I have read here and elsewhere, I could really use a few operating systems around the office which are networked together. Come to think of it, I could really dream of some pretty neat setups. Got to start somewhere! My earthquake reporting busines is really at the critical state where I could really use some employees, but the finacial end of it hasn't caught up with it yet. I do all the the work, sometimes putting in 6-7 days a week 10-16 hours a day. I'll need to clone myself in order to get the work for free and make the extra money to aquire the hardware/software upgrades. Newspapers really don't have any money and making the eq reporting busines to work was really just a shot in the dark anyway. I like to do it but there is little financial reward doing the work. Been there, done that, eh? So after reaching the break point a year ago, I decided to make that jump. I submitted a proposal to NEHRP this year to see if they would assist in the financial go of it. Should know in a couple weeks if I was a successful canidate. I hope so. I see a lot I could do with more resources but more importantly, getting appropriately compensated for the work. If the proposal doesn't work out, then it's back to the drawing board and consider the losses. Charlie Seismo-Watch _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: John Hernlund Subject: Re: New Mammoth EQ site Date: Fri, 03 Jul 1998 15:32:59 -0700 (MST) On Fri, 3 Jul 1998, Greg wrote: > Charles Watson wrote: > > Wooh-golly Frank! That's some mean 3-D GIS software! Now that I have had the > > chance to wipe the drool from my chin, I'll have to break out the ATM card and > > treat myself to a SUN Sparcstations running SUN OS-4.1.3. Gads! In my dreams! > The documentation page says, "The source code will be available in the > future for easy porting to any X11 UNIX environment." Which probably > means that with some effort you could get it to run under Linux. I have > no idea how difficult it would be and I'm not anxious to try, becuase I > have no need for it, but if you really wanted it... Linux for the Mac is > a lot cheaper than a Sun (even a used Sun). Worst case scenario you have > to prod some other people into helping you compile it for Mac Linux and > you need a little more RAM/HD space to run Linux and MacOS on the same > computer. Lees uses linux running some kind of xwindows platform for this program. ****************************************************************************** John Hernlund E-mail: hernlund@....... WWW: http://www.mc.maricopa.edu/academic/phy_sci/Geology/hernlund/ http://www.public.asu.edu/~hernlund/ "Enlightenment is man's emergence from his self-imposed immaturity. Immaturity is the inability to use one's understanding without guidance from another. This immaturity is self-imposed when its cause lies not in lack of understanding, but in lack of resolve and courage to use it without guidance from another. Sapere Aude! "Have courage to use your own understanding!"- that is the motto of enlightenment. -Immanuel Kant: "An Answer to the Question: What is Enlightenment?" ****************************************************************************** _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: frankcnd@.......... (Frank Condon) Subject: Re: New Mammoth EQ site Date: Fri, 3 Jul 1998 17:47:41 -0700 (PDT) Hi charlie: I guess it is a little way out there for the average user... I'm still using the freeware software authored by Dr. Alan Jones (SUNY)named "Seismic" on my PC for tracking events. It does 3d graphs, too. My favorite ones are the plots for the Northridge Earthquake & aftershocks. But, I have been known to use a defunct Delorme Windows program named "Map-Expert" (2d) for precise locations (One-step up from US Atlas). A new tool that I'm currently learning to use is Maptech's TopoScout for WIN95. But it's Not a 3d program and it gives elevation gains for hikers and burros. Sorry, I'm not sure if there is a MAC equivalent for any of these. BTW I own a Mac-Plus that is still used ocasionally. Frank... frankcnd@.......... "Located in the seismic corridor somewhere between Fontana & Mammoth Lakes" >Wooh-golly Frank! That's some mean 3-D GIS software! Now that I have had the >chance to wipe the drool from my chin, I'll have to break out the ATM card and >treat myself to a SUN Sparcstations running SUN OS-4.1.3. Gads! In my dreams! >Hey, if you got another lying around, I'll pay the shipping. :> > >I'll keep the URL for when my ship does come in. Thanks! > >Nevertheless, I should show a N-S x-section. My modest Mac software can handle >the data, it just takes time to generate it, which is a valuable commodity these >days when there are other mountains to climb. > >Cheers! > >-- >---/---- >Charlie >Forever chained to a vintage Mac Performa. > >Frank Condon wrote: >> >> Hello: >> Here is the URL for the software: >> http://love.geology.yale.edu/~lees/lees.html#lees.software >> >> Frank Condon >> frankcnd@.......... >> "Located in the seismic corridor somewhere between fontana & Mammoth Lakes" >> >> >On Thu, 2 Jul 1998, Charles Watson wrote: >> >> Thanks for your comments, Frank. Yea, unsure how to make the activity in >> >> the Sierra terrain stand out differently than that in the caldera >> >> without a north-south x-section. maybe if I get a couple more sponsors, >> >> I can spend the extra time in making one. (hint-hint) >> > >> >Charles, >> > Jonathan Lees at Yale has developed some cool software that makes viewing >> >and constructing seismic activity cross-sections easy...you can download it >> >from his page (I don't have the address right now but it shouldn't be >> >difficult to find). >> > >> > >_____________________________________________________________________ > >Public Seismic Network Mailing List (PSN-L) > >To leave this list email listserver@............. with the body of the >message: leave PSN-L > > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: bob ogburn Subject: Re: Can this gizmo work? Date: Fri, 03 Jul 1998 19:57:42 -0700 Angel, I built several piezo sensors several years ago using elements from a product called a "flutter fan". The sensors were used to detect rapid vertical displacement (P waves) and they seemed to work well. I suspect the sensor you created will also be most useful for short period events due to the 'stiffness' of the hinge. bob ogburn Daly City, CA PSN angel Rodriguez wrote: > Members of the list, > > I live and play in Panama (8,47 N by 82,41 W) and just lately have gotten > interesed in this wonderful hobby. I have a vertical instrument that works > well and am building several others. I keep time by reading the output of a > handheld GPS. > > The other morning I made a gizmo and posted its photo on > http://www.chiriqui.com/photo It's a 10k jpg. > > It's basically a horizontal device with a vertical pendulum but could easly > be a Lehman type. The hinge is a piezo element that I took out of a broken > phone. With my voltmeter I get quite a range of +- millivolt even with the > slightest motion. My question is: Is this use of a piezo out to lunch? Has > it been done and not proven useful? I don't want to waste my time, but if I > can build useful cheap devices, why not. > > Any comment would be very welcome. > > Angel Rodriguez > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: watson@................ (Charles Watson) Subject: [Fwd: Re: Daily Summary of Solar Geophysical Activity for 27 June] Date: Sat, 04 Jul 1998 11:57:25 -0700 FYI -- ---/---- cpw From: "Walt Williams" Subject: A SOHO Status Report Date: Sat, 4 Jul 1998 12:45:02 +0000 Charles, Thank you. Walt Williams, 98.07.04 Best 4th to the USAers of the List =================================== Date sent: Sat, 04 Jul 1998 11:57:25 -0700 From: watson@................ (Charles Watson) Organization: Advanced Geologic Exploration / Seismo-Watch To: Subject: Daily Sum'ry of Solar Geophysical Activity for 27 June Send reply to: PSN-L Mailing List FYI -- ---/---- cpw ======================================================= ------- Forwarded Message Follows ------- From: Cary Oler Subject: Re: Daily Summary of Solar Geophysical Activity for 27 June To: watson@................ (Charles Watson) Date: Fri, 3 Jul 1998 16:17:16 -0600 (MDT) > What is the status of SOHO. > Did they get it back up and running? Not yet, but they're hopeful. I've appended below the status report that we provided with yesterdays daily summary of solar and geophysical activity (which you should receive in the next few hours - our system is busy sending out all of the older stuff and it may take a few hours to begin posting the recent material). Best regards. -Cary Oler Oler@.................. Oler@......... Oler@............... or COler@.................. SOHO SPACECRAFT UPDATE ---------------------- Controllers are still attempting to regain contact with the Solar and Heliospheric Observatory spacecraft. Contact was lost on 24 June during routine maintenance activities. There apparently were several emergency safe modes activated on the spacecraft prior to the loss of telemetry. Controllers now believe the spacecraft is tumbling in a spin mode that is preventing sunlight from reaching the solar panels sufficiently to charge the batteries to allow the spacecraft to transmit and receive ground commands. Fortunately, if this assessment is correct and if the assumed spin is correct, the orientation of the spacecraft to the Sun may change over the next few weeks to permit enough sunlight to charge the batteries and allow ground controllers to determine the problems and possibly regain control. In the meantime, a board is being convened to investigate the loss of contact in greater detail. European Space Agency ground stations in Europe have now joined the effort to help regain telemetry from the spacecraft. This is in addition to the Deep Space Network radio telescopes which have been trying since the incident occurred. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "frank murray" Subject: RE: [Fwd: Re: Daily Summary of Solar Geophysical Activity for 27 June] Date: Sat, 4 Jul 1998 13:13:46 -0700 charlie forwarded: >....................Contact was lost on 24 June during >routine maintenance activities. There apparently were >several emergency safe modes activated on the spacecraft >prior to the loss of telemetry................. hmmm...i'd like knowing more about those "emergency safe modes" and their activation...is this a reference to self protective routines that the bird was designed to go into when subjected to heavy sun blasts, to partial system failure, or to "illegal" communication attempts??...systems i've helped install at secure institutions typically go into "emergency safe modes" when any operator attempts to access levels of the system above that operator's authorization... if this is all too far off topic for this list, i'm open to private e-mail from any that might wander across further info on what happened to either the HALO or that geo-sychro bird... thanks again, charlie frank _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Keith Payea Subject: Parts Source Date: Sun, 5 Jul 1998 18:54:19 -0400 I've been considering the construction of one of Sean Thomas's vertical units, and I "re-discovered" a source for some of the parts, especially t= he brass shim stock. The outfit is "Small Parts, Inc.", 1-800-220-4242 139= 80 NW 58th Court, PO Box 4650, Miami Lakes, FL 33014-0650. They have all o= f the aluminum extrusion shapes, stainless hardware, and the troublesome sh= im stock in sizes from 0.001" to 0.031" thick. A 6" by 9" piece of the 0.00= 5" stock is only $3.69. They have a $15.00 minimum, but that won't be a problem once you see the catalog! They even have some titanium hardware like machine screws and 1/4-20 threaded rod. Good Luck, Keith Keith Payea Port Hadlock Design Group phdg@.............. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Greg Subject: Re: Parts Source Date: Sun, 05 Jul 1998 20:20:20 -0700 Keith Payea wrote: > brass shim stock. The outfit is "Small Parts, Inc.", 1-800-220-4242 13980 I spend too much time on the internet... I found the URL for those of us not planning on visiting the store anytime soon. Not that they probably wouldn't send a catalog in the mail. ,Greg _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Erich F. Kern" Subject: Re: Parts Source Date: Sun, 5 Jul 1998 20:53:51 -0700 Greg, I've no idea what you've just said. What does spending time on the internet have to do with Greg's post???? Erich > From: Greg > To: PSN-L Mailing List > Subject: Re: Parts Source > Date: Sunday, July 05, 1998 20:20 > > Keith Payea wrote: > > > brass shim stock. The outfit is "Small Parts, Inc.", 1-800-220-4242 13980 > > I spend too much time on the internet... I found the URL for those of us > not planning on visiting the store anytime soon. Not that they probably > wouldn't send a catalog in the mail. > > ,Greg > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Greg Subject: Re: Parts Source Date: Sun, 05 Jul 1998 21:10:53 -0700 Erich F. Kern wrote: > I've no idea what you've just said. What does spending time on the internet > have to do with Greg's post???? Not a lot really. I just happen to be online when the message arrived and I read through it and searched for the company and posted all in one session. In fact, I haven't hung up yet. By the way, I'm Greg and I was only criticizing myself. It's not the first time it's happened. A while ago someone posted info about an electronics surplus compnay from Scottsdale, AZ? and I found the URL for it as well. It's probably in the mailing list archive files. Also I think I may have found the URL for Gateway Electronics. I hope that makes more sense. I should really hang up now, Greg _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Greg Subject: Re: Parts Source Date: Mon, 06 Jul 1998 10:19:58 -0700 Can I blame it on the internet as well? I was up too late? Not enough caffiene in my diet? Should have been dusting the furniture instead? http://www.smallparts.com/ http://www.gatewayelex.com/ Sorry, I forgot the name of the third one. And I didn't bookmark it. ,Greg _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: S-T Morrissey Subject: longer period of STM vertical Date: Mon, 6 Jul 1998 19:27:57 -0500 (CDT) Meredith, Regarding your questions about the longer period of the STM vertical. It turns out that the width and thickness of the original flexures of the leaf spring was limiting the mechanical period: ie. some of the rigidity of the spring ends was coupled into the system. In the BETA unit I had experimented and cut the lower flexures to 1/2" wide, and a 4 second period was obtainable as the upper spring support frame contact at the boom was moved toward the boom hinges. For the three new GAMMA units, I tried making the working width of both the upper and lower flexures only 1/4" wide (the soldering area is still 3/4" wide). Since the flexures are in tension, this is not a strength problem, but makes them easier to damage by excessive bending. THe thinner suspension further decouples the torques of the spring end as the boom moves and changes the angle of the spring restoring force. The period is adjusted by moving the upper spring support bar towards the hinges. A change of about 12 mm will vary the period from 2 seconds to infinity (ie. instability). Since the mechanical period affects the damping of the VBB system, the advantage of greater sensitivity or longer electronic period is traded off for a more stable mechanical period, like 6 to 10 seconds. There is still room for experimentation here. I am still packing up the new seismometers for the IRIS meeting at Santa Cruse, so I probably will not be able to post the new drawing of the seismometer until later in the month. Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: meredith lamb Subject: Home brew "speaker" magnetic enhancement Date: Mon, 06 Jul 1998 19:39:28 -0600 Hi all, If you're familar with speaker magnet construction, you might be interested in this approach of a homebrew speaker voice coil magnetic enhancement. Basically all speakers are shaped somewhat like a open ended can with a center pole welded inside on the bottom surface and extending up to a donut magnet with its space gap from the center post. Atop this is usually a donut shaped ferrite magnet. My unit has the same construction, but the only single change, was the addition of a neodymium magnet on the bottom of the container back plate. Then, the center post is sat on top of the neo. The strength of the 2 pole neo magnet is about 14K, while the ferrite donut magnet above is maybe less than 1K....depending on gap spacing. I plan on epoxying the center post to the magnet, but not to the back plate...this will allow movement for centering. The neo magnets power precludes any need for mechanical attachment. I do use a flat sheet metal backplate and a magnetic metal tube to extend the height of the assembly...which is normal. Of course the gap strength is really enhanced....maybe 5-10 times. No gaussmeter to check here though. The only interesting result other than the increased field I've seen, is that while normally the docut and center pole have equal attraction to metal, now; the neo takes over. So if you were to run a small screwdriver along the ferrite gap, it would stay there, but if you were to slightly space it from the ferrite the center pole would grab it. My Sprengnethers use the same basic construction. They are more adjustable than a store bought speaker unit. All parts can be dissassembled. My homebrew is of the same construction. The neodymium magnet I used is about 1/2" thick X 1" X 5/8" wide. Not a common size. I would expect that any 2 pole magnet of the neodymium (or Samarium) variety, would show a large field gap increase over just a plain ferrite gap. Obviously whether its used for a pickup or a feed back assembly, the sensitivity/power is increased for the coil....which is separate. My unit is not at a final stage. I will have to adopt to any coil and of the diameter of the center pole will also have to be found. If the above already exists somewhere...I don't know of it...yet-ha. Thanks, Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: meredith lamb Subject: Re: longer period of STM vertical Date: Mon, 06 Jul 1998 21:50:29 -0600 Sean-Thomas, Thanks for the reply on the longer period of your STM-Gamma unit. The period variation of 2 seconds too infinity really is fantastic for a vertical instrument! Well done Sean-Thomas! It almost sounds like with some electronic circuit and/or damping changes, it can attain long periods comparable too or over that of commercial units. Of course, I'am only guessing, but it would "seem" to be on the horizon. We'll be anxious to see the new drawings. Again, have a good time in Santa Cruz. Thanks, Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: meredith lamb Subject: Re: longer period of STM vertical Date: Mon, 06 Jul 1998 21:50:29 -0600 Sean-Thomas, Thanks for the reply on the longer period of your STM-Gamma unit. The period variation of 2 seconds too infinity really is fantastic for a vertical instrument! Well done Sean-Thomas! It almost sounds like with some electronic circuit and/or damping changes, it can attain long periods comparable too or over that of commercial units. Of course, I'am only guessing, but it would "seem" to be on the horizon. We'll be anxious to see the new drawings. Again, have a good time in Santa Cruz. Thanks, Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Steve Hammond Subject: Status- Geosource MD-100 geophones Date: Mon, 06 Jul 1998 21:49:50 -0700 Electronics goldmine USA 1-800-445-0697 FAX 602-661-8259 Http://www.goldmine item # G9621 MD-100 geophone $8.95 each US I received my order over the weekend and everything is as expected. They are small and they work (I ordered 3) 14-hrz, 335 ohm coil, and appear to be used. I connected each up to the Lehman amp ciruit provided in the PSN documentation (Op27 configured with a gain of 221 and coax driver) and was pleased with the generated waveform. They look like they should work well for recording local events. I would have like to seen them shipped with the coil shorted however. I have installed one inplace of my one of my hs10's and will match the data to vertical and N/S to see how they perform in operation. Post the findings as I receive the data. Regards, Steve PSN San Jose _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Peter Subject: Geophone Date: Mon, 06 Jul 1998 23:04:14 -0700 I have been recording with one of the geophones from electronics gold mine. Its buried 2 feet deep in a paint can with sand and is quite sensitive. I pick up noise from a nearby construction site as well as a mystery event every 5:50am on week days only? Pete Fleming _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Brian Subject: LPT:Analog? Date: Tue, 07 Jul 1998 02:33:27 -0400 Some time ago, a company called ADNAV Electronics, was selling a low cost A/D adapter that pluged in to the printer port. Does any one know if this is still available somewhere as the company appears to be out of business. It was called the LPT:Analog! v2.0 and sold for US$59.00. Thanx in advance! Brian. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Charlie Rond Subject: Event? Date: Tue, 07 Jul 1998 15:17:29 -0500 Something coming in at Memphis: 7/7/98 - 20:15uct. Charlie Rond -\/\--Public Seismic Network-Memphis http://gandlf.ceri.memphis.edu/~rond/psn _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Ken Navarre Subject: Re: LPT:Analog? Date: Tue, 7 Jul 1998 13:26:48 -0700 (PDT) On Tue, 7 Jul 1998, Brian wrote: > Some time ago, a company called ADNAV Electronics, was selling a low > cost A/D adapter that pluged in to the printer port. Does any one know if > this is still available somewhere as the company appears to be out of > business. It was called the LPT:Analog! v2.0 and sold for US$59.00. I have one of these lttle goodies. One problem is that is unipolar. I shoved a "D" cell battery in series with it to "load" it so I could get the semblance of a +/- data trace. Another problem is that it isn't supported by either EMON or SDR. I had to write a Qbasic program to view the data and still haven't gotten it to save the data to a file... :( So much for a "simple" portable solution for a field unit using a laptop... I'll check to see if I have the address (email or snail) for these guys. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Ken Navarre Subject: Re: LPT:Analog? Date: Tue, 7 Jul 1998 13:30:39 -0700 (PDT) Ah, here is the address for ADNAV. I had it tucked safely away in my bookmark file... David & Dorith Prutchi (409)292-0988 or mail (58 Chicory Ct, Lake Jackson,TX 77566) Ken _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Rex Klopfenstein, Jr." Subject: PSN - Adjustment Screws Source Date: Tue, 07 Jul 1998 18:14:23 -0400 After missing the cheap adjusting screws referred to in the past, I decided to use 1/4-28 screws. Last week I found a source of "relative" inexpensive adjustment screws. THORLABS, Inc sells 1/4-80 & 3/16-100 adjustment screws. These come in lengths from 1" to 3" with and without knobs. They also sell brass matching nuts. What is nice with these screws is that they have steel balls staked into the end of adjustment screws. By the way, the screws vary in price from $6 to $9 for 1/4 units and the nuts are in the $6 to $8 range. They accept MC, VISA, or AmEx THORLABS, INC. 435 Route 206, PO Box 366 Newton, NJ 07860-0366 973-579-7227 973-383-8406 (FAX) http://www.throlabs.com -- Rex Klopfenstein, Jr. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Rex Klopfenstein, Jr." Subject: Re: PSN - Adjustment Screws Source Date: Tue, 07 Jul 1998 19:16:36 -0400 Rex Klopfenstein, Jr. wrote: > > http://www.throlabs.com <----WRONG!!! The correct URL is http://www.thorlabs.com Sorry, my fingers got ahead of my brain!!! > > > -- > Rex Klopfenstein, Jr. > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: barry lotz Subject: Re: longer period of STM vertical Date: Tue, 07 Jul 1998 18:13:30 -0700 Sean Thomas Did moving the spring support closer reduce your mass much and consequently the gain. I'm sure there is a trade off in there, re. period vs gain. Barry _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Al Allworth" Subject: A Y2K compliance test program Date: Thu, 9 Jul 1998 23:26:35 -0700 Hi All A Y2K compliance test program can be found at: The manual method may not tell the whole story. Al _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Larry Cochrane Subject: RE: A Y2K compliance test program Date: Tue, 07 Jul 1998 23:54:14 -0700 >From: "Al Allworth" >To: "Larry Cochrane" >Subject: RE: A Y2K compliance test program >Date: Thu, 9 Jul 1998 23:39:19 -0700 >X-MSMail-Priority: Normal >X-Mailer: Microsoft Outlook 8.5, Build 4.71.2173.0 >Importance: Normal >X-MimeOLE: Produced By Microsoft MimeOLE V4.72.3110.1 > > > >Hi all, > >Sorry, the url should be: www.nstl.com > > Al > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "Francesco" Subject: LARGE EVENT NEAR AZORES ISLAND Date: Thu, 9 Jul 1998 17:19:51 +0200 05.19.07 UTC MB 6.1 Loc: ATLANTIC OCEAN - AZORES ISLAND 8 victims , many iniured e many material damnages I.ES.N. - PSN ITALY
05.19.07  UTC
MB 6.1
Loc: ATLANTIC OCEAN - AZORES = ISLAND
 
8 victims , many iniured e many = material=20 damnages
 
I.ES.N. - PSN ITALY
From: "Francesco" Subject: IRAN Date: Thu, 9 Jul 1998 17:26:17 +0200 14.18 UTC MB 6.0 Loc.: IRAN-ARMENIA-AZERBAIJAN BDR I.ES.N. - PSN ITALY
14.18  UTC
MB = 6.0
 
Loc.:  IRAN-ARMENIA-AZERBAIJAN BDR
 
I.ES.N. - PSN ITALY 
From: "David A. Nelson" Subject: LARGE Kermadec Sth PAC event Date: Fri, 10 Jul 1998 03:37:49 +1200 Hi all 15:30 utc, 9th july 98 and the surface waves are finally starting to die off S-P 3 minutes from Dunedin so event is jst Nth of the Kermadec Islands byeeeeeeee Dave Co-ordinator: New Zealand Public Seismic Network Dave A. Nelson ZL4TBN 24 Jensen St., Green Is., Dunedin, South Is.. New Zealand. http://psn.quake.net/dave/home.htm IF there indeed are other parallel universes... I can now rest in the knowledge, that in at least one of them, I am filthy rich and drive a red Ferrari _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Edward Cranswick Subject: Good luck in Santa Cruz Date: Thu, 09 Jul 1998 13:05:04 -0600 Larry & Merredith- I agree with Meredith: Good luck in Santa Cruz. meredith lamb wrote: Again, have a good time in Santa Cruz. -Edward -- Edward Cranswick Tel: 303-273-8609 US Geological Survey, MS 966 Fax: 303-273-8600 PO Box 25046, Federal Center cranswick@........ Denver, CO 80225-0046 USA E.M. Forster said, "Only connect". _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Stephen & Kathy Subject: BOOMs Date: Fri, 10 Jul 1998 18:52:41 -0700 Is there anyone in the Northern California area that is recording any Sonic Booms????? Sinse the 12 of June I have recorded, on approx 10 occasions, usually between 17:00 and 19:00 UTC, a series of 7 to 8 and on one occasion 14 BOOMs!! They are approx 15 sec apart!! I've contacted all the quarrys, the sheriffs dept., the forestry dept., the fire dept., several heavy construction contracters and no one can account for them!!! I'm still trying to determine if it could be a local mine or if I am picking up Sonic Booms from Nevada???? The last set that I recorded was this evening starting at approx (July 11, 98 00:27:40),, (July 10, 98 17:27:43 local PDT) Thanks in advance, Stephen Mortensen PSN Station #55 Pilot Hill Ca USA _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Robert Avakian Subject: Re: BOOMs Date: Fri, 10 Jul 1998 20:28:40 -0700 I understand from relatives who live near Redding that there is an artillery or munitions base which shoots off rounds about that time. I even heard on or two this spring when I was there. Could this be what you are detecting? Avakian Stephen & Kathy wrote: > > Is there anyone in the Northern California area that is recording any > Sonic Booms????? Sinse the 12 of June I have recorded, on approx 10 > occasions, usually between 17:00 and 19:00 UTC, a series of 7 to 8 > and on one occasion 14 BOOMs!! They are approx 15 sec apart!! > I've contacted all the quarrys, the sheriffs dept., the forestry dept., > the fire dept., several heavy construction contracters and no one > can account for them!!! I'm still trying to determine if it could > be a local mine or if I am picking up Sonic Booms from Nevada???? > The last set that I recorded was this evening starting at approx > (July 11, 98 00:27:40),, (July 10, 98 17:27:43 local PDT) > Thanks in advance, > Stephen Mortensen > PSN Station #55 > Pilot Hill Ca USA > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: EarthQuake Subject: Re: BOOMs Date: Fri, 10 Jul 1998 19:14:42 -0700 At 06:52 PM 7/10/98 -0700, Stephen & Kathy wrote: >Is there anyone in the Northern California area that is recording any >Sonic Booms????? >The last set that I recorded was this evening starting at approx >(July 11, 98 00:27:40),, (July 10, 98 17:27:43 local PDT) >Thanks in advance, >Stephen Mortensen >PSN Station #55 >Pilot Hill Ca USA Stephen; A very interesting scenario. Although I am not a seimso owner, this AM as my kids were about ready to go to the aquatic center in Grand Forks BC., two major and I mean major sonic booms. First time I have heard them since I moved from Cleveland in 1976! These puppies were so huge they shook my one window open and almost rattled the big sunroom windows to shatters....First came one which got me right out of my seat..then another almost as you say about 10-15 seconds later. It took a bit but we knew what they were. FYI We live at apprx. 2100 ft in the Kettle Range at 48.9 N and I forget the Long but it is close to 118. The planes were flying together from N to S which means at that speed they had to cross over from Canada! The birds came RIGHT over our octagon cabin and the noise etc...really blew us away! Bob Shannon Pinpoint EQ News _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: EarthQuake Subject: Re: BOOMs Date: Fri, 10 Jul 1998 19:33:42 -0700 At 06:52 PM 7/10/98 -0700, Stephen & Kathy wrote: >Is there anyone in the Northern California area that is recording any >Sonic Booms????? Stephen; Could you please cross-post your original on this to my list? Pinpoint@.............. Thanks Bob _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Peter Subject: Missing Quake? Date: Fri, 10 Jul 1998 19:43:54 -0700 PSN, There was a quake on the usgs page: http://quake.wr.usgs.gov/recenteqs/ It was listed as a M4.1 at about 19:18:50 (the time it arrived here) on 7/8/98. The location was just off the coast of southern CA. The map showed it as a red box so it happened within the hour and should have been on the map for 7 days? Now its gone? I think I recorded it here in San Jose on my Lehman. I would not have noticed it was gone until a friend mentioned its disappearance? Anyone know what it was or why it is gone? Thanks, Pete Fleming _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "John Krempasky" Subject: Re: Missing Quake? Date: Fri, 10 Jul 1998 22:51:02 -0400 Here's a copied section of a post from Lucy Jones of the USGS found on ca.earthquakes on USENET: A similar thing happened with the "M4.2" off San Diego. It was really a M4.8 off Baja, but with no stations nearby the automatic system mislocated it. Lucy Jones USGS/Caltech - Southern California Seismic Network speaking for myself So, it was a mislocated quake by an automatic system. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Stephen & Kathy Subject: Re: BOOMs Date: Fri, 10 Jul 1998 19:54:15 -0700 Robert Avakian wrote: > > I understand from relatives who live near Redding that there is an > artillery or munitions base which shoots off rounds about that time. I > even heard on or two this spring when I was there. Could this be what > you are detecting? > > Avakian > > Stephen & Kathy wrote: > > > > Is there anyone in the Northern California area that is recording any > > Sonic Booms????? Sinse the 12 of June I have recorded, on approx 10 > > occasions, usually between 17:00 and 19:00 UTC, a series of 7 to 8 > > and on one occasion 14 BOOMs!! They are approx 15 sec apart!! > > I've contacted all the quarrys, the sheriffs dept., the forestry dept., > > the fire dept., several heavy construction contracters and no one > > can account for them!!! I'm still trying to determine if it could > > be a local mine or if I am picking up Sonic Booms from Nevada???? > > The last set that I recorded was this evening starting at approx > > (July 11, 98 00:27:40),, (July 10, 98 17:27:43 local PDT) > > Thanks in advance, > > Stephen Mortensen > > PSN Station #55 > > Pilot Hill Ca USA At this point it could be most anything!! If no one else is recording them, then I will go back to looking for something local. If anyone needs more specific times I can give them!! Thanks for the reply, Stephen _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: EarthQuake Subject: Re: BOOMs Date: Fri, 10 Jul 1998 20:22:15 -0700 At 07:54 PM 7/10/98 -0700, Stephen & Kathy wrote: >At this point it could be most anything!! If no one else is recording >them >then I will go back to looking for something local. If anyone needs >more >specific times I can give them!! FYI My times are not specific but my wife did make mental notes, as it was such an unusual occurence. Between 11:30AM and 12:15PM PCT. I thought this was a no-no....sonic stuff over populated areas.... I realize Larry attempts and succeeds at keeping this a very focused group, but I think those who have had this happen in the past few days may find it at least indirectly related. Bob Pinpioint _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Arie Verveer Subject: One Degree ? Date: Sat, 11 Jul 1998 18:47:05 +0800 Hi, I plan to generate a Travel time table for West Australia that can be used with Winquake. I'll be using a set of tables given to me by the local geophysical observatory. (time verses distance.) But the tables used by Winquake are in degrees verses time. The question is: What is a degree? Is a degree based on the geoid height or do you need to compensate for the shape of the earth? Any help would be appreciated. Arie _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: meredith lamb Subject: Kermadec Islands Quake Lr-Lq Attenuation Date: Mon, 13 Jul 1998 09:04:29 -0600 Hi All, Am questioning the Kermadec Islands 6.3 quake of 7/9/98, which occurred at 14:45:26. Why do all the records from many amateur sources have such large P & S traces, and the LR-LQ traces have such low amplitudes? Even the records of instruments of longer period (~15 seconds up), show little amplitude. It occurred at normal depth. Alot of quakes around other ocean areas are not so affected. Thanks, Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: "David A. Nelson" Subject: Re: Kermadec Islands Quake Lr-Lq Attenuation Date: Tue, 14 Jul 1998 07:30:02 +1200 At 09:04 AM 7/13/98 -0600, you wrote: >Hi All, >Am questioning the Kermadec Islands 6.3 quake of 7/9/98, which >occurred at 14:45:26. Why do all the records from many amateur >sources have such large P & S traces, and the LR-LQ traces have >such low amplitudes? Even the records of instruments of longer >period (~15 seconds up), show little amplitude. It occurred at >normal depth. Alot of quakes around other ocean areas are not so >affected. >Thanks, Meredith Lamb Thats easy meredith, cuz the quake was not nornal depth its was ~250 km deep, the NEIC record for this event was well out, the New Zealand seismological observatory with many closer in recorders, got a far more accurate location and depth calculation here is their info which is a far better fit to the data U.T.: 1998 July 9 14:45:57 NZST: 1998 July 10 2:45:57 a.m. Lat, Long: 32.05S 176.39W Location: 341 km south-south-east of Raoul Island Focal depth: 250 km Magnitude: ML 6.5 U will also notice that there is a huge difference in location as well... 2 degrees (222km) further south and 3 degrees (333km) further west than the NEIC records. It was only when I got this data did my P and S arrivals make sense cuz I could see that the quake was somewhat closer to me that the NEIC indicated. The real problem lies in that they (NEIC) have only a few stations is this part of the world and as a result their locations, etc are often a long way out. They often locate events off shore of NZ that are really in the centre of either the North or South Island. Congrats. on ur noticing of the lack of large surface waves for such a sizeable event (Mw7.2) when I sat in front of my SDR and drum recorders and watched this event roll in, I also noted the low amplitude of the surface waves and said to myself hmmmmm a deep quake ! Take care Dave Co-ordinator: New Zealand Public Seismic Network Dave A. Nelson ZL4TBN 24 Jensen St., Green Is., Dunedin, South Is.. New Zealand. http://psn.quake.net/dave/home.htm IF there indeed are other parallel universes... I can now rest in the knowledge, that in at least one of them, I am filthy rich and drive a red Ferrari _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Stephen & Kathy Subject: major quake Date: Tue, 14 Jul 1998 21:57:16 -0700 Major Quake as I type Stephen Pilot Hill Ca USA _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Stephen & Kathy Subject: second smaller quake Date: Tue, 14 Jul 1998 22:00:28 -0700 A second smaller quake is rolling through Stephen Pilot Hill Ca _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Steve Hammond Subject: Re: second smaller quake Date: Tue, 14 Jul 1998 21:39:54 -0700 Tom's place 5.1 http://quake.usgs.gov/recenteqs/Maps/119-38.html Regards, Steve Hammond Stephen & Kathy wrote: > > A second smaller quake is rolling through > Stephen > Pilot Hill Ca > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Stephen & Kathy Subject: quake 3 Date: Tue, 14 Jul 1998 23:50:07 -0700 another small quake,,, probably about a 3.7 or 3.8 going off!! Stephen Pilot Hill _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Stephen & Kathy Subject: quake 4 Date: Tue, 14 Jul 1998 23:54:16 -0700 And another one about the same size! Stephen Pilot Hill _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Canie Brooks Subject: Re: quake 3 Date: Tue, 14 Jul 1998 23:53:37 -0700 At 11:50 PM 7/14/98 -0700, Stephen & Kathy wrote: >another small quake,,, probably about a 3.7 or 3.8 going off!! >Stephen >Pilot Hill Here it is! == PRELIMINARY EARTHQUAKE REPORT == Rapid Earthquake Location Service U.S. Geological Survey, Menlo Park, California U.C. Berkeley Seismological Laboratory, Berkeley, California Version 2: Updates lower and earlier versions of this earthquake report This is a computer-generated message -- it has not yet been reviewed by a seismologist. A LIGHT EARTHQUAKE OCCURRED AT 11:46 PM PDT Tuesday, Jul 14, 1998. THE MAGNITUDE 4.1 (ML) EVENT IS LOCATED 7 MILES WSW OF TOMS PLACE, CA THE HYPOCENTRAL DEPTH IS 3.1 MILES. PRINCIPAL EARTHQUAKE PARAMETERS _______________________________ Magnitude : 4.07 ML Event Date & Time : 07/14/1998 11:46:32 PM PDT 07/15/1998 06:46:32 UTC Location : 37.5345 N, 118.8125 W : (37 deg. 32.07 min. N, 118 deg. 48.75 min. W) Depth : 5.0 km. deep ( 3.1 miles) Location Quality : Good 12 km ( 7 miles) WSW (256 degrees) of Toms Place, CA 19 km ( 12 miles) SE (132 degrees) of Mammoth Lakes, CA 42 km ( 26 miles) WNW (297 degrees) of Bishop, CA 54 km ( 34 miles) SSE (150 degrees) of Lee Vining, CA 62 km ( 38 miles) NW (312 degrees) of Big Pine, CA ADDITIONAL EARTHQUAKE PARAMETERS ________________________________ number of phases : 160 rms misfit : 0.06 seconds horizontal location error : 0.2 km vertical location error : 0.6 km maximum azimuthal gap : 109 degrees distance to nearest station : 6. km In region 2 (098) MT. MORRISON (RSM) event ID: 51058350 ========================================================================== > >_____________________________________________________________________ > >Public Seismic Network Mailing List (PSN-L) > >To leave this list email listserver@............. with the body of the >message: leave PSN-L > > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Canie Brooks Subject: Re: quake 4 Date: Tue, 14 Jul 1998 23:57:38 -0700 At 11:54 PM 7/14/98 -0700, Stephen & Kathy wrote: >And another one about the same size! >Stephen >Pilot Hill Must be this one: == PRELIMINARY EARTHQUAKE REPORT == Rapid Earthquake Location Service U.S. Geological Survey, Menlo Park, California U.C. Berkeley Seismological Laboratory, Berkeley, California Version 2: Updates lower and earlier versions of this earthquake report This is a computer-generated message -- it has not yet been reviewed by a seismologist. A MINOR EARTHQUAKE OCCURRED AT 11:50 PM PDT Tuesday, Jul 14, 1998. THE MAGNITUDE 3.7 (ML) EVENT IS LOCATED 3 MILES E OF MAMMOTH LAKES, CA THE HYPOCENTRAL DEPTH IS 4.8 MILES. PRINCIPAL EARTHQUAKE PARAMETERS _______________________________ Magnitude : 3.69 ML Event Date & Time : 07/14/1998 11:50:56 PM PDT 07/15/1998 06:50:56 UTC Location : 37.6433 N, 118.9120 W : (37 deg. 38.60 min. N, 118 deg. 54.72 min. W) Depth : 7.8 km. deep ( 4.8 miles) Location Quality : Excellent 5 km ( 3 miles) E ( 96 degrees) of Mammoth Lakes, CA 22 km ( 14 miles) WNW (294 degrees) of Toms Place, CA 40 km ( 25 miles) SSE (152 degrees) of Lee Vining, CA 55 km ( 34 miles) NW (304 degrees) of Bishop, CA 61 km ( 38 miles) E (100 degrees) of Yosemite Village, CA ADDITIONAL EARTHQUAKE PARAMETERS ________________________________ number of phases : 142 rms misfit : 0.09 seconds horizontal location error : 0.3 km vertical location error : 0.4 km maximum azimuthal gap : 42 degrees distance to nearest station : 1. km In region 2 (090) SOUTH MOAT (LVC) event ID: 51058352 ========================================================================== > >_____________________________________________________________________ > >Public Seismic Network Mailing List (PSN-L) > >To leave this list email listserver@............. with the body of the >message: leave PSN-L > > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Fred S Subject: Re: quake 4 Date: Wed, 15 Jul 1998 17:34:04 -0700 Is it really nessecary to RE-post all the USGS reports. Seems to me anyone on this email list has web access. Just an observation as I compress my mail folder. Fred -- Gravity: It's not just a good idea. It's the LAW ! _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) From: Edward Cranswick Subject: Re: [Fwd: Re: AFTERSHOCK FORECAST] Date: Wed, 15 Jul 1998 18:52:19 -0600 Dave- The message was not sent to the Public Seismic Network (PSN), but I got my first notification of the Mammoth lakes activity from the 7 messages that PSN members posted within the first couple of hours of the quake, starting with: > Subject: > major quake > Date: > Tue, 14 Jul 1998 21:57:16 -0700 > From: > Stephen & Kathy > Reply-To: > PSN-L Mailing List > To: > PinpointEQ@........... > CC: > psn-l@............. > > > > > Major Quake as I type > Stephen > Pilot Hill Ca USA > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L > and including: > Subject: > Re: second smaller quake > Date: > Tue, 14 Jul 1998 21:39:54 -0700 > From: > Steve Hammond > Reply-To: > PSN-L Mailing List > To: > PSN-L Mailing List > References: > 1 > > > > > Tom's place 5.1 > > http://quake.usgs.gov/recenteqs/Maps/119-38.html > > Regards, Steve Hammond > > Stephen & Kathy wrote: > > > > A second smaller quake is rolling through > > Stephen > > Pilot Hill Ca > > > > _____________________________________________________________________ > > > > Public Seismic Network Mailing List (PSN-L) > > > > To leave this list email listserver@............. with the body of the > > message: leave PSN-L > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@............. with the body of the > message: leave PSN-L > > Subject: Re: AFTERSHOCK FORECAST > Date: Wed, 15 Jul 98 11:32:54 PDT > From: oppen@................ (David Oppenheimer) > To: bakun@.................... djackson@......... edward_Bortugno@........... > hfmengeo@...................... brune@............... > jdieterich@................... mori@......... > kmcnally@................. jones@....................... > reasen@.................... Rich_Eisner@........... dschwartz@......... > sieh@....................... tcasadev@................... > jdavis@.............. barbara@.................... > lind@.................... pjorgenson@......... dacox@......... > jfilson@......... cnss-list@........ beepers@.................... > warning_center@........... oppen@................... > > The NCSN/BDSN issued its first aftershock probability statement in > response to the M5.1 at Mammoth last evening. The message was issued > ~12 minutes after the mainshock. The message was sent to CA OES for > rebroadcast via their EDIS system to the wire services and was also > posted on the WWW. You can view the latter at the very bottom of the > text page for the mainshock at > > http://quake.wr.usgs.gov/recenteqs/Quakes/nc51058271.html > > So far, there have been no inquiries about the statement to either the > USGS or CA OES. Perhaps the lack of media interest was the routine > occurrence of big events at Mammoth ?? > > -David -- Edward Cranswick Tel: 303-273-8609 US Geological Survey, MS 966 Fax: 303-273-8600 PO Box 25046, Federal Center cranswick@........ Denver, CO 80225-0046 USA E.M. Forster said, "Only connect". Dave-
    The message was not sent to the Public Seismic Network (PSN), but I got my first notification of the Mammoth lakes activity from the 7 messages that PSN members posted within the first couple of hours of the quake, starting with: 
Subject: 
          major quake
     Date: 
          Tue, 14 Jul 1998 21:57:16 -0700
     From: 
          Stephen & Kathy 
 Reply-To: 
          PSN-L Mailing List 
       To: 
          PinpointEQ@...........
      CC: 
          psn-l@.............




Major Quake as I type
Stephen
Pilot Hill Ca USA

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and including:
  

Subject: 
            Re: second smaller quake
       Date: 
            Tue, 14 Jul 1998 21:39:54 -0700
      From: 
            Steve Hammond 
   Reply-To: 
            PSN-L Mailing List 
        To: 
            PSN-L Mailing List 
 References: 
            1




Tom's place 5.1 

http://quake.usgs.gov/recenteqs/Maps/119-38.html

Regards, Steve Hammond

Stephen & Kathy wrote:
> 
> A second smaller quake is rolling through
> Stephen
> Pilot Hill Ca
> 
> _____________________________________________________________________
> 
> Public Seismic Network Mailing List (PSN-L)
> 
> To leave this list email listserver@............. with the body of the
> message: leave PSN-L

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Subject: Re: AFTERSHOCK FORECAST

Date: Wed, 15 Jul 98 11:32:54 PDT

From: oppen@................ (David Oppenheimer)

To: bakun@.................... djackson@......... edward_Bortugno@...........

     hfmengeo@...................... brune@...............

     jdieterich@................... mori@.........

     kmcnally@................. jones@.......................

     reasen@.................... Rich_Eisner@...........
dschwartz@.........

     sieh@....................... tcasadev@...................

     jdavis@.............. barbara@....................

     lind@.................... pjorgenson@.........
dacox@.........

     jfilson@......... cnss-list@........ beepers@....................

     warning_center@........... oppen@...................


The NCSN/BDSN issued its first aftershock probability statement in

response to the M5.1 at Mammoth last evening.  The message was
issued

~12 minutes after the mainshock.  The message was sent to CA OES
for

rebroadcast via their EDIS system to the wire services and was also

posted on the WWW.  You can view the latter at the very bottom
of the

text page for the mainshock at


http://quake.wr.usgs.gov/recenteqs/Quakes/nc51058271.htm
l


So far, there have been no inquiries about the statement to either the

USGS or CA OES.  Perhaps the lack of media interest was the routine

occurrence of big events at Mammoth ??


-David

 

--

Edward Cranswick               
Tel: 303-273-8609

US Geological Survey, MS 966    Fax: 303-273-8600

PO Box 25046, Federal Center    cranswick@........

Denver, CO 80225-0046  USA      E.M.
Forster said, "Only connect".

 

From: Arie Verveer 
Subject: Re: Kermadec Lr-Lq Attenuation
Date: Thu, 16 Jul 1998 01:26:00 +0800

Hi Meredith,


> Am questioning the Kermadec Islands 6.3 quake of 7/9/98, which
> occurred at 14:45:26.  Why do all the records from many amateur
> sources have such large P & S traces, and the LR-LQ traces have
> such low amplitudes?

In my case I'm using a high and low frequency output from theseismometer
electronics.  I generally post the high frequency
output "AU1" + "AU3" and rarely post the low frequency "AU2"
and"AU4".  The low frequency gives a nice display on the LR-LQ
waves. Maybe I should post both on a big event?

Regards

Arie




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From: EARTHQUAKE REPORTING 
Subject: Re: [Fwd: Re: AFTERSHOCK FORECAST]
Date: Wed, 15 Jul 1998 18:46:28 -0700

At 06:52 PM 7/15/01 -0600, Edward Cranswick wrote:
>Dave-
>    The message was not sent to the Public Seismic Network (PSN), but I
got my
>first notification of the Mammoth lakes activity from the 7 messages that PSN
>members posted within the first couple of hours of the quake, starting with:

Ed etal;
The problem is net-wide and concerns both DNS lookups as well as a buried
COBAL error that has been lurking. This problem is causing multiple sends
amongst other major problems. I addressed this problem to CERN 6 weeks ago
but received no response.....BTW..It is my impression as a long time (34
years) programmer that this is another in a series of problems that will
come as a hidden scenario in this Y2K stupidity.....sort of a nested
problem but we have so many "experts" out there that nobody wants to listen
to simple logic!
Bob Shannon
Pinpoint Since 2001:->


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From: 
Subject: Re:  {EarthWaves} Re: quake  4
Date: Wed, 15 Jul 1998 22:39:18 EDT

Uh.... Fred?

We got the message -- three times. Looks like your server is hiccuping again.

:) 

Adrienne

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From: meredith lamb 
Subject: SG Electronics
Date: Wed, 15 Jul 1998 21:32:53 -0600

Hi Arie,

I'd be interested in seeing your low frequency event files
for the bigger events.  Am amazed by what I've seen in the past
for the SG response.  Your seismo is the smallest I've seen,
but it sure seems to work well for near and far quakes.

Guess I have more of a long period seismo interest. 

Do have a question.....is your electronics basically the same as
per the PSN schematic, or...is it different, or is it Larry Cochranes
commercial amplifier model?

Thanks, Meredith Lamb


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From: Karl Cunningham 
Subject: Tiltmeter Concept
Date: Thu, 16 Jul 1998 08:45:15 -0700

Greetings --

An item crossed my desk at work that has been patented (Pat no 5,632,093),
that is a tiltmeter design I hadn't seen before.  It contains an
arrangement of coils similar to that of an LVDT, but instead of having a
moving core it is partially submerged in a ferromagnetic fluid.  This fluid
provides the magnetic coupling from primary to the secondaries.  As the
apparatus is tilted (or accelerated), the fluid covers more of one
secondary and less of the other, and causes an imbalance in the output of
the pickup coils.

Cute idea.  Just thought some of you might be interested.




Karl Cunningham
La Mesa, CA.
PSN station #40
karlc@.......

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From: Doug Crice 
Subject: Re: quake  4
Date: Thu, 16 Jul 1998 09:51:07 -0700

I rather appreciate the re-posting of the USGS reports.  It's an easy
way to get the magnitude and location, which doesn't usually come
through the usual messages.  Sure, I could look it up, but I wouldn't.
-- 
Doug Crice          web site http://www.georadar.com
GeoRadar Inc.             e-mail dcrice@............
19623 Via Escuela Drive           phone 408-867-3792
Saratoga, CA 95070 USA              fax 408-867-4900


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From: Karl Cunningham 
Subject: Re: quake  4
Date: Thu, 16 Jul 1998 13:17:30 -0700

I subscribe to the Quake-L email list from LISTSERV.NODAK.EDU.  Although it
is not limited to USGS reports, there is so little other traffic it might
as well be.

I offer this as a suggestion that might satisfy some people -- one could
get the reports automatically yet not have them come through this list.


Karl Cunningham
La Mesa, CA.
PSN station #40
karlc@.......

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From: Robert Avakian 
Subject: Re: quake  4
Date: Thu, 16 Jul 1998 15:56:53 -0700

How do we subscribe to the service?  

Bob Avakian

Karl Cunningham wrote:
> 
> I subscribe to the Quake-L email list from LISTSERV.NODAK.EDU.  Although it
> is not limited to USGS reports, there is so little other traffic it might
> as well be.
> 
> I offer this as a suggestion that might satisfy some people -- one could
> get the reports automatically yet not have them come through this list.
> 
> Karl Cunningham
> La Mesa, CA.
> PSN station #40
> karlc@.......
> 
> _____________________________________________________________________
> 
> Public Seismic Network Mailing List (PSN-L)
> 
> To leave this list email listserver@............. with the body of the
> message: leave PSN-L


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From: "Francesco" 
Subject: ADRIATIC SEA   e SANTA CRUZ
Date: Thu, 16 Jul 1998 23:55:57 +0200

h 17.29   UTC
MB 4.4
Located: Central Adriatic Sea  - Greece-Albania border region

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

All italian station had registered at 14.16 Utc  Santa Cruz Island quake =
 Ms 6.6
Good S  and large LQ -  LR


Francesco Nucera
I.E.S.N.  - PSN ITALY









h 17.29   UTC


MB 4.4


Located: Central Adriatic Sea  =
-=20
Greece-Albania border region


 


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


 


All italian station had registered =
at 14.16=20
Utc  Santa Cruz Island quake  Ms 6.6


Good S  and large LQ - =20
LR


 


 


Francesco Nucera


I.E.S.N.  - PSN=20
ITALY


From: Arie Verveer 
Subject: Re: SG Electronics
Date: Fri, 17 Jul 1998 03:15:17 +0800

Hi Meredith

> I'd be interested in seeing your low frequency event files
> for the bigger events.

What luck,  the " Ms6.6 Santa Cruz Islands " is a good exampleof the low
frequency response of the seismometer. I've
just posted the event to the PSN event list.
{High frequency "AU3" ,  Low frequency "AU4"}
I haven't post filtered the data but did cut the samples down to
10 per second to save space in posting.


> Do have a question.....is your electronics basically the same as
> per the PSN schematic, or...is it different, or is it Larry Cochranes
> commercial amplifier model?
>

Its Larry's commercial amplifier. The only thing that I havechanged is the
low frequency response for the N-S seismometer.
It was made to respond to slightly higher frequency's and thus
give a reasonable "P" and "S" wave from the events that come
from the Java trench area. I left the E-W alone.
The amplifier works very well.


All the best


Arie.



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From: meredith lamb 
Subject: SG Electronics
Date: Thu, 16 Jul 1998 22:36:19 -0600

Hi Arie,

Thanks for the fast service on the Santa Cruz quake and your
low frequency seismogram response-ha.  Luck yes!

Interesting.  I put one gram behind the other up against a lamp,
and except (generally) for the short period waves amplitude,
theres not a great deal of difference overall.

Obviously, the amplifier does indeed work well.

Two more questions.  Whats the weight of your S-G mass?
Whats your hinge material, thickness, width, and distance
between hinges?  For comparison to the original on the PSN site.

...........

>From all the PSN seismograms I've seen of the Santa Cruz
Islands quake, it appears like the travel times for deeper quakes
and phases like, Lq-Lr, is obviously shorter than standard surface
quakes, as none seem to really match up as marked for their
apparent respective phases...including mine of course-ha.

Thanks, Meredith Lamb





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From: "David A. Nelson" 
Subject: ANOTHER large west Pacific event 
Date: Fri, 17 Jul 1998 21:42:42 +1200


  09:30 UTC  17 July     another large west pacific event in progress

 surface waves  now dying off for me and  tony in hawaii


Dave

Co-ordinator:
New Zealand
Public Seismic Network
			Dave A. Nelson   ZL4TBN
			24 Jensen St.,   
			Green Is., Dunedin,  
			South Is.. New Zealand.  

http://psn.quake.net/dave/home.htm   

IF there indeed are other parallel universes... I can now rest in the
knowledge, that in at least one of them, I am filthy rich and drive a red
Ferrari


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From: "Francesco" 
Subject: LARGE EVENT
Date: Fri, 17 Jul 1998 12:56:39 +0200

LARGE SURFACE WAVE
08.50 UTC
NEW GUINEA?

FRANCESCO NUCERA
I.E.S.N. PSN ITALY









LARGE SURFACE WAVE


08.50 UTC


NEW GUINEA?


 


FRANCESCO=20
NUCERA


I.E.S.N. PSN ITALY


From: barry lotz 
Subject: Re: ANOTHER large west Pacific event
Date: Fri, 17 Jul 1998 04:47:29 -0700

Hi
 Picked it up here in California also.
                             Barry


>David A. Nelson wrote:
> 
>   09:30 UTC  17 July     another large west pacific event in progress
> 
>  surface waves  now dying off for me and  tony in hawaii
> 
> Dave
>

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From: Karl Cunningham 
Subject: Re: quake  4
Date: Fri, 17 Jul 1998 10:50:34 -0700

Bob --

Here are the instructions for the QUAKE-L list:

The QUAKE-L list is for general discussions about earthquakes. The list
covers a wide range of topics from discussions of specific earthquakes and
the after-effects to various theories and scientific principles of
earthquakes and related phenomena. QUAKE-L is now on
listserv@.................. (host site is the North Dakota Higher Education
Computer Network).

To subscribe to the list send e-mail to listserv@.................. with
the command:

sub quake-l [your_first_name your_last_name]
For example: sub quake-l James Witt
You will be asked to confirm your subscription and will then be sent
further information about workings of the LISTSERV server. The QUAKE-L
owner/manager is Marty Hoag, hoag@................. 

Karl Cunningham
La Mesa, CA.
PSN station #40
karlc@.......


At 03:56 PM 7/16/98 -0700, you wrote:
>How do we subscribe to the service?  
>
>Bob Avakian
>


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From: barry lotz 
Subject: Santa Cruz vs Papua NG
Date: Fri, 17 Jul 1998 18:10:07 -0700

Dave 
   The pervious discussion about surface waves and event depth is
displayed in the difference between these two events. One at around 33k
with large surface wave component and the other at 110k w/o much surface
wave component. Both are in the same general area . Good call.
                                       Barry

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From: Arie Verveer 
Subject: Re: SG Electronics
Date: Sat, 18 Jul 1998 20:08:23 +0800

Hi Meredith,

> Two more questions.  Whats the weight of your S-G mass?
> Whats your hinge material, thickness, width, and distance
> between hinges?  For comparison to the original on the PSN site.
>

The Pendulum weighs around 70 grams. The hinge is made up oftwo separate brass hinges some
0.002" in thickens by 8 millimetres
wide and 5 mm between the hinges. The hinges are separated by
28 mm between centres. The pendulum has a natural frequency
around  1 Hertz.

Image at:

http://www.iinet.net.au/~ajbv/SG/Penbulum/Pendulum.htm

I should include these numbers in the web page. I'll put
it on the list of things to do.

All the best.

Arie.




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From: "Margarida Conde" 
Subject: SDR questions
Date: Sat, 18 Jul 1998 15:38:26 +0100

Two questions about SDR:
1) How to keep the SDR time accurate?
In the documentation I´ve found references to a short wave radio receiver.
Are there any alternatives? For instance, can I keep my PC clock accurate by
the network?
Which DOS software should I use? Can SDR do that alone?
2) Where to get the latest version of SDR? I believe that the one at
http://psn.quake.net is not the latest one. Am I wrong?
TIA
Margarida Conde
mconde@...............



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From: bob ogburn 
Subject: Re: SDR questions
Date: Sat, 18 Jul 1998 09:10:57 -0700

In response to Q1:
The method used here is to synchronize the local clock using the SNTP (pr=
otocol)
as described in RFC 1796.
It is important to select a time server that has the most consistent path=
 as
determined by using trace route.
This technique is not automatic, you must periodically run a time synch t=
o
correct your local clock.
In Windows, I use the time sync routine in a program called NetScanTools
(shareware from Kirk Thomas), a very useful suite.
To obtain a DOS compatible program, search for SNTP at the shareware site=
s.

An alternative, real-time method would be to recover the UTC information =
from a
GPS receiver and record it using your data collection routine.

bob ogburn PSN Daly City California E-W SG

Margarida Conde wrote:

> Two questions about SDR:
> 1) How to keep the SDR time accurate?
> In the documentation I=B4ve found references to a short wave radio rece=
iver.
> Are there any alternatives? For instance, can I keep my PC clock accura=
te by
> the network?
> Which DOS software should I use? Can SDR do that alone?
> 2) Where to get the latest version of SDR? I believe that the one at
> http://psn.quake.net is not the latest one. Am I wrong?
> TIA
> Margarida Conde
> mconde@...............
>
> _____________________________________________________________________
>
> Public Seismic Network Mailing List (PSN-L)
>
> To leave this list email listserver@............. with the body of the
> message: leave PSN-L




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From: "David A. Nelson" 
Subject: 3RD BIG SW Pacific quake
Date: Sun, 19 Jul 1998 08:30:02 +1200

hi all
           the 3rd big quake in this pa4rt of the world in as many days

  Ms6.0  in the Vanuatu Islands


 BTW  the Mw7.1  from the nth coast of  PNG  caused a 7 metre   (~22ft)
tsunami  drowning at least 70 ppl  as it wiped out coastal villages in this
VERY remote part of the country.

Dave


Co-ordinator:
New Zealand
Public Seismic Network
			Dave A. Nelson   ZL4TBN
			24 Jensen St.,   
			Green Is., Dunedin,  
			South Is.. New Zealand.  

http://psn.quake.net/dave/home.htm   

IF there indeed are other parallel universes... I can now rest in the
knowledge, that in at least one of them, I am filthy rich and drive a red
Ferrari


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From: Larry Cochrane 
Subject: Re: SDR questions
Date: Sun, 19 Jul 1998 15:21:30 -0700

Hi Margarida,

At 03:38 PM 7/18/98 +0100, you wrote:
>Two questions about SDR:
>1) How to keep the SDR time accurate?
>In the documentation I´ve found references to a short wave radio receiver.
>Are there any alternatives? For instance, can I keep my PC clock accurate by
>the network?
>Which DOS software should I use? Can SDR do that alone?

Here in the lower United States (from what I hear WWV does not work very
well in Alaska, and Hawaii has WWVH so it should work very well there) SDR
users can use WWV, or WWVB with the new release of SDR coming out soon. It
can also use the serial port that is connected up to another system that
can send out accurate time. The serial port can be use to daisy chain
several SDR systems together, if you need more than 6 channels, or it can
be connected up to a system that is using NTP (Network Time Protocol) or
some other means to keep its clock accurate. SDR then checks the time on
the other system every 15 minutes and uses this info for its internal time
keeping.  

NTP should work fine if the time server system is connected up to a high
speed link into the Internet. With a 28k modem there can be several 100ths
of milliseconds latency, so the time jumps around a lot.

I think the way to go for people who can not receive WWV/WWVB or don't want
to setup another system to act as time server, is to use GPS. One of the
main drawbacks too using GPS is cost. Too get a GPS receiver with accurate
time output, one needs a special unit. The off the shelf GPS receivers are
not designed with accurate timing output in mind. If someone knows of a
commercial unit that does have good time (< 10Ms) output please let me /
the group know. 

I am working with Ray (sorry I don't know Ray's last name) at
rayv@............................ He has purchased a unit that has the 1
pulse per second output need for accurate time keeping. He will be sending
the unit to me this week so I can add the code need to use it with SDR.
Maybe Ray can tell us more about the cost and where he got it. I believe
the cost is around $250.00. The receiver costs around 180.00 but you still
need an antenna, box and power supply etc.

One more thing about SDR. SDR does not use the computers time except when
it first start up. After reading the systems time at startup of the
program, SDR keeps track of the time by using the 1 ms interrupt generated
by the A/D card. This is why running TSRs like RIGHTTIME does not help. In
fact, they can cause problems by disabling interrupts too long and causing
SDR to miss interrupts.

>2) Where to get the latest version of SDR? I believe that the one at
>http://psn.quake.net is not the latest one. Am I wrong?
>TIA

The version I have on my site is very old. I am shipping version 2.2 with
my A/D card and I have the next release almost ready. I want to add the GPS
code before I release the next version.  I will send Margarida, and anyone
else who would like to have it, the current release and the current beta
release.

Regards,
Larry Cochrane
Redwood City, PSN




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From: Greg 
Subject: Re: SDR questions
Date: Sun, 19 Jul 1998 16:12:41 -0700

Larry Cochrane wrote:

> If someone knows of a
> commercial unit that does have good time (< 10Ms) output please let me =
/
> the group know.

I metioned this before. I don't think it went to the list though.
http://www.tapr.org/ has lots of GPS and timing stuff. However it's all
in a kit form. The recievers are probably like Ray's with the seperate
antenna. They have some software TAC-32 (Totally Accurate Clock) that
shows the time and the number of satellites and signal strength and
stuff, but I don't think it acts as a time server. It does adjust the
hardware clock though. If there was a Windows 95 based network time
server, it would be pretty good. I don't know of any.

From the web page:
"The software can automatically reset the PC=EDs internal clock with 25
msec accuracy."
It's not 10ms but I doubt WWV is either.

TAPR (Tucson Amateur Packet Radio) is a ham club of sorts, but I doubt
you'd need a license to buy the recievers. There is a discount to
members, of which I am not. Which is not unreasonable since I am now a
ham in Tucson. The club is somewhat nationally (at least) known.

I did a lot of searching for commercial time servers and WWV recievers
and everything I found was too expensive to even look at. For me at
least. I did see some equipment under $3,000. I think that this would be
a decent place for a Linux time server with a GPS receiver plugged into
the serial port and a network card in it. Of course that means 2
computers running 24 hours. If one computer could handle the GPS and the
SDR, that would be ideal.

Sorry about the short choppy sentences,
Greg

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From: Steve Hammond 
Subject: Re: SDR questions
Date: Sun, 19 Jul 1998 20:09:27 -0700

Larry Cochrane wrote:
>=20
> Hi Margarida,
>=20
> At 03:38 PM 7/18/98 +0100, you wrote:
> >Two questions about SDR:
> >1) How to keep the SDR time accurate?
> >In the documentation I=B4ve found references to a short wave radio rec=
eiver.


Here is a WWV clock for $99.95 with a serial interface. I was thinking
about getting this and giving it a try. It keeps time if WWV is lost.=20
http://www.feist.com/~bodegroup/arc5.html=20

Regards, steve Hammond PSN San Jose

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From: Bob Fryer 
Subject: Quake sensitives on PBS
Date: Mon, 20 Jul 1998 18:21:57 -0700

Hello folks,

Saw "Savage Earth" part 1 and 2 last night on PBS, and it was well done.

Tonight's episodes, parts 3 and 4, should have some of my earthquake
sensitive friends.  Ali Rhoden of SoCal, who was interviewed for the show,
is one of the more sensitive of them.  I have spent several weeks with her
family.

Am really curious to see how they treat the subject.  Many of us were
interviewed or taped for another show that will air in Britain in
September, here later, on Discovery Channel.

Also, enjoyed the too brief meeting with Larry Cochrane at the IRIS seminar.

Take care,
Bob Fryer


----- earthquake WARNING research -----
--- animals, people, scientific evidence ---
---  http://www.teleport.com/~bfryer ---



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From: "Rex Klopfenstein, Jr." 
Subject: PSN-SDR Board & PC Power Saving Functions
Date: Mon, 20 Jul 1998 21:27:37 -0400

I have just upgraded an old 386 minitower to a 166MHz Pent.  I bought
the mother board and CPU for about $170 (since the Pent II came out, the
Pent equipment has really dropped in price!!).  I have my SDR board in
it running WIN98 without any problems.

These new boards have provisions to power down the monitor and spin down
the hard drive.  This would be nice for a machine that sets there doing
nothing but watching incoming signals for most of the time.

My questions to the low level system wizards are as follows:

Will the SDR software let the monitor and disk drive shut down or will
it see activity that keeps the equipment active?

Will I lose any data if I let the system shutdown the disk drive?  My
gut feeling is it shouldn't because there should be enough buffer to
queue data until disk gets up and running.

Thanks in advance

Rex Klopfenstein, Jr
Bowling Green, OH


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From: Pinpoint 
Subject: Re: Quake sensitives on PBS
Date: Mon, 20 Jul 1998 18:31:00 -0700

At 06:21 PM 7/20/98 -0700, Bob Fryer wrote:
>Hello folks,
>
>Saw "Savage Earth" part 1 and 2 last night on PBS, and it was well done.

It is still on here in the PNW at 49 degrees but obvious that Ali and
Kathys parts are over... A number of things struck me...

 #1 It must have cost a lot of money to do a show like this...lots and
lots...Ali spent much time worrying and thinking about he taping crew which
came in, but only had a few seconds on a big long show...Of course that
part of timing is understood, but imagine the amount of money that must
have gone into this production. I think the show as a whole was very
dynamic and VERY VERY Good!

  #2...To You Kathy F. You must have been a looker cus you still ARE!:->
And I say that with all honesty. What an honest, youthfull and enjoyable
few seconds I had seeing you! I am so glad your feeling a bit better!

    Now having said that Ali----Of course you and Larry were too cool....as
were the pics of the Punchbowl....I fell so very priviledged to know you
both! And thank you also for your support and help over the years! What a
great show!

>Also, enjoyed the too brief meeting with Larry Cochrane at the IRIS seminar.

Add to that Bob F. that you might have seen Steve Malone the author of the
software for Iris..Did you get to see him? I have only talked with him via
email and once in a great while.........What a group! I am now totally
impressed!
Again!
Bob

 
>Take care,
>Bob Fryer
>
>
>----- earthquake WARNING research -----
>--- animals, people, scientific evidence ---
>---  http://www.teleport.com/~bfryer ---
>
>
>
>_____________________________________________________________________
>
>Public Seismic Network Mailing List (PSN-L)
>
>To leave this list email listserver@............. with the body of the 
>message: leave PSN-L
>
>

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From: Larry Cochrane 
Subject: IRIS workshop earlier this month
Date: Mon, 20 Jul 1998 23:42:42 -0700

Hi Everyone,

Sorry for not writing about this sooner. The last few weeks have been very
hectic...

The workshop entitled "Teaching Seismology Using Education Software" went
very well. I presented WinQuake and also talked about the PSN and our web
sites. There where 10 presentations, and about 20 other people, each
lasting about 30 minutes. The first few presentations where Web based
teaching tools and information / data sites.

Bob Woodward, from Albuquerque Seismological Laboratory, talked about their
LISS service. LISS stands for Live Internet Seismic Server. What they have
done is place some, currently 29 of the 115, broadband seismic stations on
the Internet. The data from these stations are sent to Albuquerque using
the Internet and then re broadcasted, again using the Internet, to anyone
who wants the data in near real time. There is about 30 to 60 seconds of
latency from the time the sensor records the data and to when you get it.
More info about LISS can be found at
http://aslwww.cr.usgs.gov/Seismic_Data/liss.htm.

After the web based talks there was only one person who present a Mac based
software package. All of the rest where PC based. The Mac based program is
called Wiggles. It is similar to WinQuake in that it is used to analyze
event files. It can read / write SAC binary files.

One program called DIMAS was interesting. Bob Woodward also presented this
one.  DIMAS is used to analyze seismograms. They pass it out to their
remote station operators so they can look at the data produced by the
seismometer and do some simple analyses. This program can try and locate
the event using one three component station. The azimuth is determined by
the partial motion based on the P wave and the distance using the P and S
wave. Since the azimuth and distance are known, the approximate location
can be determined. It can also locate the event based on multiple station P
and S wave distances. It also has the ability to display the information on
a map. What's nice about DIMAS is they supply the source code, in "C"!!!

I have already added two new features to WinQuake. One uses the travel time
table used by DIMAS. The file is similar to the JB travel time tables
currently used by WinQuake, but contain more phases and all of the data is
located in one 2 Meg file (it zips down to around 400K). It seems to be
only useful for teleseismic events. The regional JB travel time tables seem
to work better for local events, so I will not be removing the JB table
support. The other thing I am playing around with is the mapping feature. I
currently have WinQuake displaying a map with the stations and distance
circles based on the event file windows and the placement of the P and S
markers in each window. What I need to do before I get too far into this is
to make sure that I can use the data and code from their program. I hope to
add other features from DIMAS if I get permission and as I can find time to
do it.

Michelle HallWallace, she hosted the event, has created a web page at
http://www.geo.arizona.edu/K-12/azpepp/education/software/IRIS.software.html
.. The page has links to all of the information presented at the workshop.
This page may move to somewhere under www.iris.edu at some point.

One thing that was a little strange, and several people pointed this out,
was the no one from PEPP (Princeton Earth Physics Project) was there. Since
their organization is based on placing seismometers in high schools, one
would think they would have someone there showing their software and
learning about what others are doing. Several people came up to me and ask
if we (PSN) are doing anything with PEPP. I had to say very little. I
explained that several of their members are using WinQuake and that John
Taber, from the Victoria University of Wellington in New Zealand, is using
some of the PSN hardware/software and incorporating the course work from
the PEPP.

Regards,
Larry Cochrane
Redwood City, PSN
  




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From: "William Combs" 
Subject: RE: IRIS workshop earlier this month
Date: Tue, 21 Jul 1998 13:41:00 -0500



Larry,

I do not know what happened to PEPP but I heard a hacker got into their
server and I have not been able to upload files since. Here in central
Indiana I have been able to pick up most M6.0 quakes on their seismograph.
M5.5 or greater out of Central America. I hopefully will get a webpage up on
the school server this fall.

One thing that was a little strange, and several people pointed this out,
was the no one from PEPP (Princeton Earth Physics Project) was there. Since
their organization is based on placing seismometers in high schools, one
would think they would have someone there showing their software and
learning about what others are doing. Several people came up to me and ask
if we (PSN) are doing anything with PEPP. I had to say very little. I
explained that several of their members are using WinQuake and that John
Taber, from the Victoria University of Wellington in New Zealand, is using
some of the PSN hardware/software and incorporating the course work from
the PEPP.

Regards,
Larry Cochrane
Redwood City, PSN





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From: S-T Morrissey 
Subject: STM seis at IRIS workshop
Date: Tue, 21 Jul 1998 14:08:10 -0500 (CDT)

Re. IRIS workshop at Santa Cruz

To answer some queries about the presentations at the IRIS workshop
at Santa Cruz July 8 to 11. I unfortunately did not meet Larry C,
since his seminar was Wednesday morning and I finally found the 
right location about 5 PM (the maps were really cryptic) where the 
posters were to be set up. I was asked to present a working STM seis
as well as one to have hands-on contact. Of course the working seis
had limited stability on a table top, but everyone got the idea.
The presentations were up for all three days, and interest in the
seis led others to help with the explanations while I attended
other formal presentations of the workshop.

The poster portion was the calibration and noise data from the March
presentation at the SSA (Seismological Society of America) meeting 
in Boulder; nothing new, but the comparisons of the STM data
with regional commercial VBB sensors (the Streckeisen STS-1) had
many asking why they were paying around $15k for the STS-1. Many
wanted to sign up for a "production" copy of the sensor, or at least
for the electronics box.  I had used the Validyne electronics for the 
VRDT displacement transducer and a completely "passive" feedback
(no amplifiers and a R-C-R integrator) for the demo, which greatly 
reduced the high frequency response as expected, but made the 
feedback seem quite simple for a response that was flat from 1 hz
to 50 seconds or so.

The most consistent concerns were about the physical size, which
complicates the pressure containment of the vertical, and the 
thermal response, which needs some serious study. The size can be
reduced if the boom is shortened, which requires a lot more clearance
of the coil within the magnet (of the 10" speaker). THis brings
up the options of modifying the magnet gap (with a machine lathe)
or winding a coil less than about 0.5mm thick.  The thermal response
of the leaf spring may need some active compensation.

The few copies of the current mechanical drawing of the seis 
disappeared; I will hopefully scan it and post it on the web 
later this week.

I had hoped to see more of the PEPP (Princeton Earth Physics Project)
program, but there was not much presented. There was a poster 
about adding a capacitive displacement sensor to a 4.5hz geophone, 
requiring complicated machining. I have recently successfully
added a VRDT to a 4.5 hz phone in a much simpler fashion, but have
not implemented it with a VBB response ... yet. (Such a VBB sensor
will have an inherently high noise level because the mass is only
22 grams.)

Regards,
Sean-Thomas.

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From: Larry Cochrane 
Subject: Re: PSN-SDR Board & PC Power Saving Functions
Date: Tue, 21 Jul 1998 23:02:21 -0700

At 09:27 PM 7/20/98 -0400, Rex Klopfenstein, Jr wrote:
>I have just upgraded an old 386 minitower to a 166MHz Pent.  I bought
>the mother board and CPU for about $170 (since the Pent II came out, the
>Pent equipment has really dropped in price!!).  I have my SDR board in
>it running WIN98 without any problems.

SDR will have problems with time keeping if it is run inside of a DOS box.
Does Win98 have a DOS only mode similar to Win95?

>
>These new boards have provisions to power down the monitor and spin down
>the hard drive.  This would be nice for a machine that sets there doing
>nothing but watching incoming signals for most of the time.

I recommend that all of the motherboard Green power monitoring stuff be
disabled. I ran into problems with SDR dropping interrupts do to the
interrupt monitoring done by the power monitoring. Also, SDR is not just
sitting there waiting for an event. It is constantly saving all of the data
it records too disk. This gives it the ability to replay the data to see
what you got at a particular time and not rely only on triggered data.

>
>My questions to the low level system wizards are as follows:
>
>Will the SDR software let the monitor and disk drive shut down or will
>it see activity that keeps the equipment active?

Since SDR is saving data too disk every minute, you don't want to start and
stop the motor that often. I really don't think the few cents, if that,
saved each month is worth the trouble. Starting and stopping a motor
constantly will cut down on the life of the drive. The few cents save would
be lost if you need to buy a new drive. With portable computers it make
more sense to save every watt....

The monitor is another story. It uses a lot more power than a motor and
turning it on and off makes more sense.

>
>Will I lose any data if I let the system shutdown the disk drive?  My
>gut feeling is it shouldn't because there should be enough buffer to
>queue data until disk gets up and running.

Again, SDR uses the disk drive too often to turn it on and off.

-Larry Cochrane
Redwood City, PSN


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From: Fred S 
Subject: Re: PSN-SDR Board & PC Power Saving Functions
Date: Tue, 21 Jul 1998 23:09:01 -0700

Win 98 Power save functions may have some bugs.  My system and 2 other's
at my company all lock up periodicly when the monitor powers down. 

Just a warning

Fred
-- 
Gravity:  It's not just a good idea.  It's the LAW !

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From: Larry Cochrane 
Subject: Re: PSN-SDR Board & PC Power Saving Functions
Date: Tue, 21 Jul 1998 23:32:58 -0700

A bug in Win98??? Unbelievable...

-Larry

At 11:09 PM 7/21/98 -0700, Fred S wrote:
>Win 98 Power save functions may have some bugs.  My system and 2 other's
>at my company all lock up periodicly when the monitor powers down. 
>
>Just a warning
>
>Fred
>-- 
>Gravity:  It's not just a good idea.  It's the LAW !
>
>_____________________________________________________________________
>
>Public Seismic Network Mailing List (PSN-L)
>
>To leave this list email listserver@............. with the body of the 
>message: leave PSN-L
>

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From: Jim Hannon 
Subject: Re: PSN-SDR Board & PC Power Saving Functions
Date: Wed, 22 Jul 1998 06:11:35 -0500

Larry Cochrane wrote:
> 
> 
> SDR will have problems with time keeping if it is run inside of a DOS box.
> Does Win98 have a DOS only mode similar to Win95?
> 
Win98 has the same DOS only mode as Win95. In fact overall Win98 is so
similar to Win95 that I question calling it a new OS :)


-- 
Jim Hannon
http://soli.inav.net/~jmhannon/
42,11.90N 91,39.26W
WB0TXL


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From: watson@................ (Charles Watson)
Subject: Re: IRIS workshop earlier this month
Date: Wed, 22 Jul 1998 07:51:25 -0700

Thanks for the IRIS report. A lot of useful stuff. Could you send me a 
contact for the Mac based Wiggles program?

-- 
---/----
Charles P. Watson
Seismo-Watch

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From: watson@................ (Charles Watson)
Subject: Larry, I found it..
Date: Wed, 22 Jul 1998 07:54:22 -0700

Larry, I found more info about the Wiggles program at Michelle 
HallWallace's web page. 

Thanks again for your report!

-- 
---/----
Charles P. Watson
Seismo-Watch

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From: meredith lamb 
Subject: Re: STM seis at IRIS workshop & Magnet reworking concern
Date: Wed, 22 Jul 1998 14:16:54 -0600

Sean-Thomas,

With your message it sounds like the STM-8 was a big success,
and drew alot of interest at the IRIS workshop.  Congratulations!

In regards to reworking the magnet (as is) on a machine lathe, it
might ruin the ferrite on clamping of the lathe head, as its pretty
fragile stuff.  The chips from any successful cutting will also be a
problem of removal.  Even if the center pole washer edge is
clamped and cutting commences, the ferrite may still shatter from
the cutting pressure on the upper washer.  The steel is tough stuff.

Had the bad experience of trying drilling a hole on the center pole
side, tapping, and using a 1/4-20 bolt to force the washers apart,
with the idea of washers/ferrite separation.  Turns out the ferrite
is securely glued to the washers, and the glue held, but the ferrite
didn't....ugh!  The width of the ferrite from the outer edge to the
inner ID edge is .950".  I also misjudged the width of the magnet
and promptly learned that ferrite readily dulls drills..from that,
it would appear that trying to rework ferrite alone is a tough task.

Aside from the cost of machining and the risk of the voice coil
magnet destruction, offhand, it would not appear to be the better
choice of approach.  The choices would seem to be...

1.  Leave it as is.
2.  Find another commercial speaker thats workable.
3.  Homebrew a speaker magnet assembly and/or borrow a
    coil from a commercial speaker,etc, or make your own coil.

FB magnets/coils rule...seismometrists drool-ha.  Ahem....

Anyway...will be looking forward to your new mechanical drawing.

Meredith Lamb


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From: "Rex Klopfenstein, Jr." 
Subject: Re: PSN-SDR Board & PC Power Saving Functions
Date: Wed, 22 Jul 1998 17:54:41 -0400



Larry Cochrane wrote:

> >SDR will have problems with time keeping if it is run inside of a DOS box.
> >Does Win98 have a DOS only mode similar to Win95?
>

Yes, from what I understand WIN98 is better described as a service release than
new program.  When I load SDR I generated a DOS shortcut and there is a DOS box
in WIN98.


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From: barry lotz 
Subject: Re: STM seis at IRIS workshop & Magnet reworking concern
Date: Wed, 22 Jul 1998 16:37:35 -0700

Hi
 I bought two ceramic grade 5 ring magnets from an outfit in Calif a few
years ago. The Dowling Miner Magnets corp.(1-800-magnet-1) 707-935-0352.
they were 4.33" OD and 1.77" ID  0.425" thick and cost around $10 ea.
They had a pretty good selection of ring magnets.
                                           Barry

meredith lamb wrote:
> ....
> In regards to reworking the magnet (as is) on a machine lathe, it
> might ruin the ferrite on clamping of the lathe head, as its pretty
> fragile stuff.  The chips from any successful cutting will also be a
> problem of removal.  Even if the center pole washer edge is
> clamped and cutting commences, the ferrite may still shatter from
> the cutting pressure on the upper washer.  The steel is tough stuff.
> 
> Had the bad experience of trying drilling a hole on the center pole
> side, tapping, and using a 1/4-20 bolt to force the washers apart,
> with the idea of washers/ferrite separation.  Turns out the ferrite
> is securely glued to the washers, and the glue held, but the ferrite
> didn't....ugh!  The width of the ferrite from the outer edge to the
> inner ID edge is .950".  I also misjudged the width of the magnet
> and promptly learned that ferrite readily dulls drills..from that,
> it would appear that trying to rework ferrite alone is a tough task.
> 
> Aside from the cost of machining and the risk of the voice coil
> magnet destruction, offhand, it would not appear to be the better
> choice of approach.  The choices would seem to be...
> 
> 1.  Leave it as is.
> 2.  Find another commercial speaker thats workable.
> 3.  Homebrew a speaker magnet assembly and/or borrow a
>     coil from a commercial speaker,etc, or make your own coil.
>

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From: barry lotz 
Subject: Owens Valley
Date: Wed, 22 Jul 1998 19:20:19 -0700

I was listening to NPR with regards to the restoring water to the
Owens Valley. That area has been awfully quiet since the 1872 event. Has
anyone heard about the potential affect of the restoring water to the
valley and it's affect on potential earthquakes? 
                                  Barry

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From: Greg 
Subject: Re: Owens Valley
Date: Wed, 22 Jul 1998 20:27:44 -0700

barry lotz wrote:

> anyone heard about the potential affect of the restoring water to the
> valley and it's affect on potential earthquakes?

In Tucson, Arizona the city is supposedly "recharging the water supply"
with water routed from somewhere else? I'm somewhat new here and I don't
know all of the facts, but no earthquakes yet ;) I doubt the water is
being forced in under any pressure like the Denver deal.

,Greg

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From: Jim Hannon 
Subject: Re: STM seis at IRIS workshop & Magnet reworking concern
Date: Wed, 22 Jul 1998 22:44:06 -0500

meredith lamb wrote:
> 
> In regards to reworking the magnet (as is) on a machine lathe, it
> might ruin the ferrite on clamping of the lathe head, as its pretty
> fragile stuff.  The chips from any successful cutting will also be a
> problem of removal.  Even if the center pole washer edge is
> clamped and cutting commences, the ferrite may still shatter from
> the cutting pressure on the upper washer.  The steel is tough stuff.
> 
> Had the bad experience of trying drilling a hole on the center pole
> side, tapping, and using a 1/4-20 bolt to force the washers apart,
> with the idea of washers/ferrite separation.  Turns out the ferrite
> is securely glued to the washers, and the glue held, but the ferrite
> didn't....ugh!  The width of the ferrite from the outer edge to the
> inner ID edge is .950".  I also misjudged the width of the magnet
> and promptly learned that ferrite readily dulls drills..from that,
> it would appear that trying to rework ferrite alone is a tough task.
> 
I have successfully enlarged the gap in a speaker manget assembly on a
lathe. The magnet holds all the cuttings in the gap, this makes it hard
to see what you are doing and cut smoothly. Also the soft iron is gummy
and cuts more like copper than steel. It however can be done with light
cuts and a lot of patience.

The way to spearate the glue is with heat. If you are careful you can
soften the glue before you reach the Curie temp. of the ferrite.

Ferrite is really hard. I dulled a carbide drill enlarging a hole in a
ferrite bead that I was using for a flux gate magnetometer.
-- 
Jim Hannon
http://soli.inav.net/~jmhannon/
42,11.90N 91,39.26W
WB0TXL


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From: bschafer@.........
Subject: KFWB news clip
Date: Wed, 22 Jul 1998 23:58:57 -0500 (CDT)

Here is something that I heard on the news and thought it might be of 
interest.  I ran and got my tape recorder and got exactly what was said.  
Here it is following.


"Your greatest risk may not be from the San Andreas or the big 
mountain-building thrust faults.  KFWB's Jack Popejoy reports the study
combined GPS data with traditional geology.
Study co-author Dr. James Dolan of the Southern California Earthquake 
Center tells KFWb this doesn't change the overall seismic risk just our 
understanding of the risk the smaller surface faults running right 
through the urban area present.  "A lot more energy is being stored up 
on certain faults that we call strike slip faults--more than we thought 
in the past.  The flip side of that is that that energy that is being 
stored up on the strike slip faults isn't being stored on the big thrust 
faults that are building our mountains."  "The four leading strike slip
fault candidates in the study are the Verdugel fault, the Raymond,
the San Josae, and the Chino fault.  You can find them through the KFWB
web service at kfwb.com.  Just go to our news page."

Anyway, thought that was very interesting.  I thought that most faults 
in the Southern California area are strike slip faults.

Also, please forgive my spelling on some of these names.



Bonnie
the crafty crafter

 



Bonnie
the crafty crafter


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From: Norman Davis WB6SHI 
Subject: Re: Owens Valley
Date: Thu, 23 Jul 1998 07:35:15

At 07:20 PM 7/22/98 -0700, you wrote:
>I was listening to NPR with regards to the restoring water to the
>Owens Valley. That area has been awfully quiet since the 1872 event. Has
>anyone heard about the potential affect of the restoring water to the
>valley and it's affect on potential earthquakes? 
>                                  Barry

 The big deal in the owens goes back to the 20's. LA water and power
purcased all the land and then sold it without water rights. then took all
they wanted for use in LA. They also created lakes in the sierra and take
all that too. It has been at times a war like environment between the folks
up there and LA. That may be what they are talking about.

 BTW: Just came back from a drive from big pin to bridgport. Lots of water.
No shaking. Rats....

Norman Davis WB6SHI
Shingle Springs, Ca
normd@.............
http://www.directcon.net/normd/index.htm


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From: Robert Avakian 
Subject: Re: Owens Valley
Date: Thu, 23 Jul 1998 10:47:46 -0700

This may be off the subject a bit but, Mono Lake is one of, if not the
last of the unique rangefront lakes not dired out by LAPW and a very
significant breeding area for various birds.  I first encountered the
lake in 1970 doing field work as a grad student.  It is a very
impressive and magical place.  Locals fought the water people and won a
landmark decision protecting the lake.  However, the LAPW people are
trying any number of ways to slip out of the decision and subsequent
agreements.  The lake is a real treat as are the Mono craters nearby.  

The Mono Lake Committee (the white hats) are at PO Box 29, Lee Vining,
CA, 93541.  They are also on the web, i believe.
Bob Avakian


Norman Davis WB6SHI wrote:
> 
> At 07:20 PM 7/22/98 -0700, you wrote:
> >I was listening to NPR with regards to the restoring water to the
> >Owens Valley. That area has been awfully quiet since the 1872 event. Has
> >anyone heard about the potential affect of the restoring water to the
> >valley and it's affect on potential earthquakes?
> >                                  Barry
> 
>  The big deal in the owens goes back to the 20's. LA water and power
> purcased all the land and then sold it without water rights. then took all
> they wanted for use in LA. They also created lakes in the sierra and take
> all that too. It has been at times a war like environment between the folks
> up there and LA. That may be what they are talking about.
> 
>  BTW: Just came back from a drive from big pin to bridgport. Lots of water.
> No shaking. Rats....
> 
> Norman Davis WB6SHI
> Shingle Springs, Ca
> normd@.............
> http://www.directcon.net/normd/index.htm
> 
> _____________________________________________________________________
> 
> Public Seismic Network Mailing List (PSN-L)
> 
> To leave this list email listserver@............. with the body of the
> message: leave PSN-L


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From: Edward Cranswick 
Subject: [Fwd: Santa Cruz Seismic Instruction Software]
Date: Thu, 23 Jul 1998 16:51:16 -0600



--
Edward Cranswick                Tel: 303-273-8609
US Geological Survey, MS 966    Fax: 303-273-8600
PO Box 25046, Federal Center    cranswick@........
Denver, CO 80225-0046  USA      E.M. Forster said, "Only connect".

Jan-
	I thought that you, Steve, and Ted might do something, and I think that
I forwarded some kind of info to the PSN-L.  However, I was not really
connected with it myself, and I wasn't going to try to tell you guys
what you should do (what maybe I should have helped to do myself).  In
any case, the IRIS meeting does not get as much coverage as the AGU
meetin in San Francisco in December which Larry and Ted attended last
year with me.  So I think it would be a great idea to pursue the idea
that you and Ted talked about last year of having a bunch of students
submit a poster for the AGU meeting 6-10 December this year
. You guys can write the
abstract and prepare the poster and I, as an AGU member, can sponsor it
and get the USGS to pay for it. The abstract deadline for that is: 

	August 26, 1998		(Postal/express mail submissions)

        September 2, 1998	(Interactive Web Form submissions) 

	Because we only have about a month, please let me know ASAP what you
think and also CC a copy to me at  which what
I am trying to make my address for PSN-related activities.
-Edward

Jan Froom wrote:
> 
> It's a shame that we couldn't have gone to this conference, since I think
> Steve, Ted & I  are about the only ones in this area that are actually working
> with schools.... well Elementary, Middle & High.  I tried, and got a note from
> a lady in Arizona that forwarded my request to a lady in Santa Cruz....  but
> after that I got no answer.
> ---------------------- Forwarded by Jan Froom/San Jose/IBM on 07-22-98 11:26 AM
> ---------------------------
> 
> Ted Blank
> 07-21-98 01:13 PM
> To: Jan Froom/San Jose/IBM@IBMUS
> cc:
> From: Ted Blank/Santa Teresa/IBM @ IBMUS
> Subject: Re: Santa Cruz Seismic Instruction Software
> 
> I tried to get the information from Larry but it was all very vague.  Finally
> he called me the night before to say it was the next day but by that time I had
> other plans.  Oh well.
> 
> Regards, Ted
> DB2 Performance, IBM Santa Teresa Lab, San Jose, California
> 
> Ted Blank/Santa Teresa/IBM .....(from Notes)
> IBMUSM50(TED) .............................(from PROFS/VM)
> ted@.......... ..............................(from internet sites)
> STLVM6(BLANK) .............................(for LIST3820 files etc.)
> Tie: 8-543-3589    Ext:  (408) 463-3589   Fax:  (xxx-2614)

-- 
Edward Cranswick                Tel: 303-273-8609
US Geological Survey, MS 966    Fax: 303-273-8600
PO Box 25046, Federal Center    cranswick@........
Denver, CO 80225-0046  USA      E.M. Forster said, "Only connect".


From: Edward Cranswick 
Subject: Papua New Guinea tsunami
Date: Thu, 23 Jul 1998 17:12:12 -0600

PSN-
    Here are three interesting and instructive websites about the Papua
New Guinea tsunami:

    http://omzg.sscc.ru/tsulab

    http://walrus.wr.usgs.gov/docs/tsunami/PNGhome.html

    http://www.theage.com.au/special/png/index.html

The human suffering in PNG is beginning to sound horrible.
-Edward
--
Edward Cranswick                Tel: 303-273-8609
US Geological Survey, MS 966    Fax: 303-273-8600
PO Box 25046, Federal Center    cranswick@........
Denver, CO 80225-0046  USA      E.M. Forster said, "Only connect".




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From: barry lotz 
Subject: Re: Owens Valley
Date: Thu, 23 Jul 1998 17:17:21 -0700

Greg
   The reason it came to mind was that I had heard of the increase in
seismic activity with the construction of certain dams(I don't remember
which). However dams do produce a much larger static head.
                                        Barry
 
Greg wrote:
> 
> barry lotz wrote:
> 
> > anyone heard about the potential affect of the restoring water to the
> > valley and it's affect on potential earthquakes?
> 
> In Tucson, Arizona the city is supposedly "recharging the water supply"
> with water routed from somewhere else? I'm somewhat new here and I don't
> know all of the facts, but no earthquakes yet ;) I doubt the water is
> being forced in under any pressure like the Denver deal.
> 
> ,Greg
>

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From: Robert Avakian 
Subject: Re: Owens Valley
Date: Thu, 23 Jul 1998 20:01:04 -0700

As I remeber, the seismic activity was atrtributed to the loading of the
water, too.


barry lotz wrote:
> 
> Greg
>    The reason it came to mind was that I had heard of the increase in
> seismic activity with the construction of certain dams(I don't remember
> which). However dams do produce a much larger static head.
>                                         Barry
> 
> Greg wrote:
> >
> > barry lotz wrote:
> >
> > > anyone heard about the potential affect of the restoring water to the
> > > valley and it's affect on potential earthquakes?
> >
> > In Tucson, Arizona the city is supposedly "recharging the water supply"
> > with water routed from somewhere else? I'm somewhat new here and I don't
> > know all of the facts, but no earthquakes yet ;) I doubt the water is
> > being forced in under any pressure like the Denver deal.
> >
> > ,Greg
> >
> 
> _____________________________________________________________________
> 
> Public Seismic Network Mailing List (PSN-L)
> 
> To leave this list email listserver@............. with the body of the
> message: leave PSN-L



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From: Mike Lozano 
Subject: Re: Owens Valley
Date: Fri, 24 Jul 1998 06:49:40 -0500



barry lotz wrote:

> Greg
>    The reason it came to mind was that I had heard of the increase in
> seismic activity with the construction of certain dams(I don't remember
> which). However dams do produce a much larger static head.
>                                         Barry
>
> Greg wrote:
> >
> > barry lotz wrote:
> >
> > > anyone heard about the potential affect of the restoring water to the
> > > valley and it's affect on potential earthquakes?
> >
> > In Tucson, Arizona the city is supposedly "recharging the water supply"
> > with water routed from somewhere else? I'm somewhat new here and I don't
> > know all of the facts, but no earthquakes yet ;) I doubt the water is
> > being forced in under any pressure like the Denver deal.
> >
> >

Barry,

A few dams suffering increased seismic activity after filling are:  Hoover Dam
had a 5.0 in 1940.  Since that time, reportedly, seismicity has decreased.
All the quakes were on the east side of the dam, with a focal depth of less
than 8 km.

Lake Kariba in Zambia (filled in 1958) had a 5.8 in 1963, and decreased
activity since.
It was the last quake in a series of 2000 minor tremors.

Koyna, India had a 6.5 in 1967 which killed 200 and injured 1500.  Seismic
activity has generally followed rainfall patterns.

The filling of the Aswan High Dam on Lake Nasser has set off numerous quakes,
the heaviest of which, happened in 1981.

Funny, I was just browsing through Bruce Bolt's 'Earthquake' when your email
comment popped up on my screen.

Regards, Mikel Lozano



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From: barry lotz 
Subject: Re: Owens Valley
Date: Thu, 23 Jul 1998 19:21:14 -0700

Mike & Greg
    Thanks for the feedback.
                 Barry

>Mike Lozano wrote:
> 
> Barry,
> 
> A few dams suffering increased seismic activity after filling are:  Hoover Dam
> had a 5.0 in 1940.  Since that time, reportedly, seismicity has decreased.
> All the quakes were on the east side of the dam, with a focal depth of less
> than 8 km.
> 
> Lake Kariba in Zambia (filled in 1958) had a 5.8 in 1963, and decreased
> activity since.
> It was the last quake in a series of 2000 minor tremors.
> 
> Koyna, India had a 6.5 in 1967 which killed 200 and injured 1500.  Seismic
> activity has generally followed rainfall patterns.
> 
> The filling of the Aswan High Dam on Lake Nasser has set off numerous quakes,
> the heaviest of which, happened in 1981.
> 
> Funny, I was just browsing through Bruce Bolt's 'Earthquake' when your email
> comment popped up on my screen.
> 
> Regards, Mikel Lozano

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From: frankcnd@.......... (Frank Condon)
Subject: Re: Owens Valley
Date: Thu, 23 Jul 1998 22:06:42 -0700 (PDT)

From what I've heard the Owens River Valley was kind of like the bread 
basket of the Eastern Sierras in it's heyday before the LA aqueduct.

Frank Condon
"Located in the Seismic Corridor Somewhere Between Fontana & Mammoth Lakes"

>At 07:20 PM 7/22/98 -0700, you wrote:
>>I was listening to NPR with regards to the restoring water to the
>>Owens Valley. That area has been awfully quiet since the 1872 event. Has
>>anyone heard about the potential affect of the restoring water to the
>>valley and it's affect on potential earthquakes? 
>>                                  Barry
>
> The big deal in the owens goes back to the 20's. LA water and power
>purcased all the land and then sold it without water rights. then took all
>they wanted for use in LA. They also created lakes in the sierra and take
>all that too. It has been at times a war like environment between the folks
>up there and LA. That may be what they are talking about.
>
> BTW: Just came back from a drive from big pin to bridgport. Lots of water.
>No shaking. Rats....
>
>Norman Davis WB6SHI
>Shingle Springs, Ca
>normd@.............
>http://www.directcon.net/normd/index.htm
>
>
>_____________________________________________________________________
>
>Public Seismic Network Mailing List (PSN-L)
>
>To leave this list email listserver@............. with the body of the 
>message: leave PSN-L
>
>


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From: Edward Cranswick 
Subject: is there anybody out there?
Date: Fri, 24 Jul 1998 12:51:13 -0600

Larry-
    I posted two messages to the PSN-L yesterday and have received no
acknowlegement that they were received and neither have been posted.  Is it me
or you or both of us?
--
Edward Cranswick                Tel: 303-273-8609
US Geological Survey, MS 966    Fax: 303-273-8600
PO Box 25046, Federal Center    cranswick@........
Denver, CO 80225-0046  USA      E.M. Forster said, "Only connect".




_____________________________________________________________________

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From: Canie Brooks 
Subject: Re: is there anybody out there?
Date: Fri, 24 Jul 1998 11:56:21 -0700

They are there!  I've gotten them - one on AGU and seismic instruction
software and another on the PNG tsunamis...

Canie

At 12:51 PM 7/24/98 -0600, Edward Cranswick wrote:
>Larry-
>    I posted two messages to the PSN-L yesterday and have received no
>acknowlegement that they were received and neither have been posted.  Is
it me
>or you or both of us?
>--
>Edward Cranswick                Tel: 303-273-8609
>US Geological Survey, MS 966    Fax: 303-273-8600
>PO Box 25046, Federal Center    cranswick@........
>Denver, CO 80225-0046  USA      E.M. Forster said, "Only connect".
>
>
>
>
>_____________________________________________________________________
>
>Public Seismic Network Mailing List (PSN-L)
>
>To leave this list email listserver@............. with the body of the 
>message: leave PSN-L
> 

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From: S-T Morrissey 
Subject: Re: Owens Valley
Date: Fri, 24 Jul 1998 19:14:40 -0500 (CDT)

Re induced seismicity from reservoirs:

I had the opportunity of working in the USSR exchange program in
the late '70s on installing seismic telemetry around large reservoirs
that had the potential of inducing seismicity or modifying the
release of accumulating slip potential. The first was the 350 meter
high Nurek reservoir near Dushanbe in Tadjikistan on the Naryn
river just west of the Hindu Kush ranges. The other was at Totugul
in Kirgisia, on the Talas-Fergana fault system. The Nurek reservoir
would cause quakes anytime the level was rapidly dropped, like more
than 10 meters per day. This would unburden the pressure on the 
faults, alowing the high pore pressure induced  by the impoundment
to lubricate the faults. Raising the water level would turn off
the quakes.
A general rule of thumb for induced seismicity is that the impoundment
has to exceed 100 meters in depth. The general concept is that the
hydrostatic pore pressure increase and/or the vertical load do not
of themselves cause earthquakes, but modify the way accumulating
regional stress is released.
I doubt if refilling Mono lake would in itself induce seismicity;
The Owens valley has enough potential of its own.

Regards,
Sean-Thomas

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From: bschafer@.........
Subject: cranswick@......................
Date: Fri, 24 Jul 1998 19:27:59 -0500 (CDT)

is there anybody out there?
  
Hi, just got this message loud and clear and thought I would let you 
know.

Just got a very good book written by Bruce Bolt called "Earthquakes."  A 
very good and well written book for the person who doesn't know much 
about seismology.  He had another one there but didn't have enough cash 
to get it right then.  I saw it at Borders bookstore.


Bonnie
the crafty crafter


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From: S-T Morrissey 
Subject: STM-8 drawings
Date: Fri, 24 Jul 1998 20:17:15 -0500 (CDT)

I have finally posted the latest drawings of the hardware-
store seismometer on the web site at:

http://www.eas.slu.edu/People/STMorrissey/index.html

under the "figures and drawings" page. The seismometer
drawings are of two dimensions only; the overhead view
can generally be deduced from the side view because of
the natural symmetry of the design.

Regards,
Sean-Thomas

_____________________________________________________________________

Public Seismic Network Mailing List (PSN-L)


From: Edward Cranswick 
Subject: Include PSN in seismic network survey?
Date: Fri, 24 Jul 1998 21:33:27 -0600

PSN-
    As usual, I am passing this on a bit late, but I am still trying to
unravel the enigmatic link or lack thereof I have with the PSN-L.  So I
am sending this out to see our response.
-Edward

********************************************************************
Subject:
         Request for network information
   Date:
         Wed, 8 Jul 1998 10:23:28 -0700 (PDT)
   From:
         Steve Malone 

I have sent e-mail to all of the official CNSS network representatives
and
alternates regarding the need for information for an "Assessment of
Seismic Monitoring in the US" and a contribution to an IASPEI
publication.
If anyone associated with a regional network who should have gotten
this notice but did not you may find it posted on the WEB at URL:

        http://www.cnss.org/NETS/request.survey.txt

Please try to make sure that any seismic network you are associated with

will be responding to this request.

        Thanks,


        Steve Malone                    E-mail:
steve@......................
        Geophysics Program              Phone: (206) 685-3811
        University of Washington        FAX: (206)543-0489
        Box 351650                      Office: ATG-226
        Seattle, WA 98195       http://www.geophys.washington.edu



--
Edward Cranswick                Tel: 303-273-8609
US Geological Survey, MS 966    Fax: 303-273-8600
PO Box 25046, Federal Center    cranswick@........
Denver, CO 80225-0046  USA      E.M. Forster said, "Only connect".




_____________________________________________________________________

Public Seismic Network Mailing List (PSN-L)


From: meredith lamb 
Subject: Re: STM-8 drawings
Date: Fri, 24 Jul 1998 23:00:15 -0600



S-T Morrissey wrote:

> I have finally posted the latest drawings of the hardware-
> store seismometer on the web site at:
>
> http://www.eas.slu.edu/People/STMorrissey/index.html
>
> under the "figures and drawings" page. The seismometer
> drawings are of two dimensions only; the overhead view
> can generally be deduced from the side view because of
> the natural symmetry of the design.
>
> Regards,
> Sean-Thomas
>

Thanks for posting the new drawings on the web site.  Took off
3 drawings: Leafspring 4, Vertseis 5 & 6 drawings with no problem.
The enhanced Vertseis 6, seemed to be much clearer here.

A magnificent public contribution....

Thanks, Meredith Lamb




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From: meredith lamb 
Subject: Re: Papua New Guinea tsunami
Date: Fri, 24 Jul 1998 23:03:27 -0600

Edward Cranswick wrote:

> PSN-
>     Here are three interesting and instructive websites about the Papua
> New Guinea tsunami:
>
>     http://omzg.sscc.ru/tsulab
>
>     http://walrus.wr.usgs.gov/docs/tsunami/PNGhome.html
>
>     http://www.theage.com.au/special/png/index.html
>
> The human suffering in PNG is beginning to sound horrible.
> -Edward
> --

It indeed does appear to be a big disaster.  Perhaps a part of
the replication is the economics, life span, life style, education,
etc.  Sad results that are more a fact of life in alot of parts of the
world, and hard to write about.

Makes me wish that there was perhaps some form of a cheap
seismic instrumentation available that might help save some lives.
For remote and electrical powerless locations like that, solar
sun cells would work for rechargeables....but the cost just for
those items would be prohibitive in their economy, and there
likely isn't any real knowleable and responsible party in every
village.  True, for this quake, some 12 odd miles/kilometers
offshore they would have felt it strongly; but for more distant
quakes, they may not, and yet....get the same results.

I'am not aware of any government promotion of earthquake
awareness outside the U.S., Japan, and China.  Its possible
they simply can't afford even simple equipment to distrubute
over numerious villages etc.  Communication equipment is not
likely even considered, due to higher cost, and also it is not
automated in response or alarm.

For power saving features, it would almost seem to be essential
to use power saving items like eddy current damping of the
seismometer.  Any circuit would have to operate on minimum
battery draw.  Such a circuit would likely have to have some kind
of audio alarm for threshold exceeded limits.  Waterproof.  Likely
buried for long term.  Geophones are probably the most
attractive candidates for such a scheme.....if there is any undertaken
.....wherever...and if ever...

I know you're strong on earthquake safety and awareness.  Perhaps with
time, better and cheaper instrumentation can assist in reducing any
quake loss results due to limited budgets, and; increase more critical
concerned public personnel like yourself.  Here or abroad.


Meredith Lamb


_____________________________________________________________________

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From: meredith lamb 
Subject: Re: Include PSN in seismic network survey?
Date: Sat, 25 Jul 1998 00:31:14 -0600

Hi Edward,

Seems too me, you "enigmatic" (puzzling) link to PSN has been
around about 15 years-ha.  Guess you will have to accept the
fact of your convictions, that a wider arena (PSN), has brought
both enlightenment to yourself and mostly to us....as students.

Summertime silence on PSN.  Happens every year is my guess.

Anyway....checked out the survey list.  Do have a question or
two.  I can't quite believe they list Wood-Andersons horizontal
seismometers thereon?  I thought that went out with the great
extinctions-ha.  Probably the simplest design ever created.  Hmmm,
maybe with newer sensors attached it could come back........
like...with a vrdt or ?   No joke meant here.  Simpler is better.
Equipment is always a major hurdle with anybody, government
or private amateur.

The survey looks like it is a re-creation of a much older document.
Photo recording?  No one I know of....    The 24 bit recording is
a possible future dream.....

The survey is revealing, interesting, puzzling with the abbreviations,
kind of elongated with mystic reasoning redish tape, and etc.
Uhhh......YOU... do... understand all that stuff don't you?-ha.

Alot of things have changed in your 15 years, there weren't there
before.  More things will change in the future...and you'll be there to
be a part of it...

Thanks for the survey surprise.

Meredith Lamb



_____________________________________________________________________

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From: watson@................ (Charles Watson)
Subject: Re: Papua New Guinea tsunami
Date: Sat, 25 Jul 1998 08:46:24 -0700

Meredith -

Noble words. It was following last year's NE Venezuela 7.1 earthquake that 
my bell rang. In reporting on the event, I was in constant contact with a 
Venezuela Newspaper, radio station and the University. I heard first hand of 
the rescue efforts for two schools which totally collasped killing all or 
most the children and their teachers inside. It wrenched my guts out as the 
radio station broadcasted live over the internet a rescue team's failed 
attempts to save a small child trapped in the school rubble. Just as they 
broke an openning to reach her, an aftershock hit and brought more rubble 
down, sealing the childs fate and injuring some of the rescue workers. 
Really, really horrible. 

But what's really sad is these losses could have been prevented by better 
building codes and improved siting of critical structures like schools, 
hospitals, etc. It was a known area of strong earthquake activity and yet 
they continued to build in the soft sediments around the bay. Unfortuantely, 
this kind of disaster is not restricted to the third world. I pray when the 
Hayward or Seattle faults (just to name a pair) rupture that they are of 
modest magnitudes rather that their maximum crediable.

Prior to the Venezuela earthquake, I had almost a boyish passion to tracking 
earthquake activity. The larger the better and I wished I could be there to 
feel the energy released from the rupture. While the passion is still there, 
it is tempered with the reality that some of these large earthquakes will 
occur on land and cause extreme trauma to the region. My role in the seismic 
reporting world has changed and I emphasis early detection and warning, 
along with preparedness before, during and after the earthquake.

There has been much descussion about the early warning systems but none 
implimented here in the States. Anyone know of the progress towards 
establishing these systems?

-- 
---/----
Charles P. Watson
Seismo-Watch

meredith lamb wrote:
> 
> Edward Cranswick wrote:
> 
> > PSN-
> >     Here are three interesting and instructive websites about the Papua
> > New Guinea tsunami:
> >
> >     http://omzg.sscc.ru/tsulab
> >
> >     http://walrus.wr.usgs.gov/docs/tsunami/PNGhome.html
> >
> >     http://www.theage.com.au/special/png/index.html
> >
> > The human suffering in PNG is beginning to sound horrible.
> > -Edward
> > --
> 
> It indeed does appear to be a big disaster.  Perhaps a part of
> the replication is the economics, life span, life style, education,
> etc.  Sad results that are more a fact of life in alot of parts of the
> world, and hard to write about.
> 
> Makes me wish that there was perhaps some form of a cheap
> seismic instrumentation available that might help save some lives.
> For remote and electrical powerless locations like that, solar
> sun cells would work for rechargeables....but the cost just for
> those items would be prohibitive in their economy, and there
> likely isn't any real knowleable and responsible party in every
> village.  True, for this quake, some 12 odd miles/kilometers
> offshore they would have felt it strongly; but for more distant
> quakes, they may not, and yet....get the same results.
> 
> I'am not aware of any government promotion of earthquake
> awareness outside the U.S., Japan, and China.  Its possible
> they simply can't afford even simple equipment to distrubute
> over numerious villages etc.  Communication equipment is not
> likely even considered, due to higher cost, and also it is not
> automated in response or alarm.
> 
> For power saving features, it would almost seem to be essential
> to use power saving items like eddy current damping of the
> seismometer.  Any circuit would have to operate on minimum
> battery draw.  Such a circuit would likely have to have some kind
> of audio alarm for threshold exceeded limits.  Waterproof.  Likely
> buried for long term.  Geophones are probably the most
> attractive candidates for such a scheme.....if there is any undertaken
> ....wherever...and if ever...
> 
> I know you're strong on earthquake safety and awareness.  Perhaps with
> time, better and cheaper instrumentation can assist in reducing any
> quake loss results due to limited budgets, and; increase more critical
> concerned public personnel like yourself.  Here or abroad.
> 
> Meredith Lamb
> 
> _____________________________________________________________________
> 
> Public Seismic Network Mailing List (PSN-L)
> 
> To leave this list email listserver@............. with the body of the
> message: leave PSN-L

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From: Mike Lozano 
Subject: Re: Papua New Guinea tsunami
Date: Fri, 24 Jul 1998 19:05:47 -0500

Charles & Meredith & everyone else,

It was with a great deal of interest that I read both of your messages.  It's so
true that every time we see a gigantic squiggle, someone else pays the price.  I
face the same thing in my field of meteorology.  Everytime there's a microburst
or tornado or hail, etc.,etc... someone pays the price; but the years of
intrepreting data and drawing conclusions has begun to pay off in the earlier
warnings we're seeing now.  Just 2 weeks ago, the Des Moines area was hit with a
large tornado.  Due to the early warning generated by doppler radar and
mesoscale analysis algorithms (some of which I had a miniscule part in
developing), no one died.  Hopefully, at some time in the future, earthquakes
and tsunami will be as predictable.

On your other note, a few years ago, I developed a lahar warning device that is
so cheap it's considered expendable.  It's solar charged, consumes 50
microamperes, and is pretty much fail-safe.  I even got a patent on it (mostly
for my own vanity), and offered it to a university (I now forget if it was the
Univ. of Michigan) for free.  Guess what?  I never even received a reply to my
offer.  So much for the advancement of affordable warning devices.  I hope I'm
not stepping on any toes, but sometimes the "not invented here" syndrome is
alive and well - unfortunately, the cost is to those who don't wind up alive and
well.

comments?

Mikel Lozano
-0-


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From: Fred S 
Subject: Re: Papua New Guinea tsunami
Date: Sat, 25 Jul 1998 12:36:37 -0700

Meredith, In a situation like PNG or any other place 
of poor economy and high risk. It seems a low cost GO/NO GO 
system could be implimented. The actual magnitude and location 
is not so important as just an indication of an event exceeding a
pre-set threshold. 

What about low cost geophones like the type used in oil exploration. I
have been using these to monitor local activity with good results.
Coupled with some low power CMOS electronics and a simple burst type
transmitter. This could be a low cost alternative to a complicated
network.

Fred

-- 
Gravity:  It's not just a good idea.  It's the LAW !

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From: watson@................ (Charles Watson)
Subject: Re: Papua New Guinea tsunami
Date: Sat, 25 Jul 1998 14:23:30 -0700

Mikel -

I have mixed feelings too. Sometimes I have looked at the squiggles on =

the seismograph and wondered: Wow, that=B9s a big one! where was it! =

surface fault ruptures?... But then reality sets in: who was =

effected?...who suffered?...who died this time?... At almost the same =

time, my scientific side of me is charged with excitement, but the other =

is sadden by the potential loss and suffering.

Perhaps under different situations the value of human life would be =

elevated. In some situations we, as a species, are willing to risk one =

life in order save an other. But in the harsh world of global economics =

and product development, the amount of lives saved is factored into the =

financial cost. Product cost vs. lives saves - and erie thought on its =

own, the price of human life vs. product development. If life is so =

valuable, why are willing to expend the ultimate sacrifice, another =

human life, just to save one other. But when thousands of lives could be =

save at a profit in product development, we jump on the campaign and =

indeed it is done. Or sadly in turn, not choose a product because it =

does not save enough lives for the amount spent.

And then there is art, science, and medicine. There is a fine line an =

artist, scientist, or physician must walk in order to do their job - to =

compose the emotional distraught scene, determine the answers to some =

pretty tough questions, or perform a difficult procedure in surgery - =

some of which may mean maybe one or hundreds of human lives were either =

lost or saved. I admire the experts in their fields, yet understand the =

pain they must have endured to achieve their status. Wise people must =

endure suffering, therefore, wisdom comes at a valuable cost, one beyond =

financial measure. =


I often look at the PSN group as people with wisdom beyond their years. =

The potential is greater than the current sum, knowing the mean will =

satisfy the many. =



                                       - Charlie



-- =

---/----
Charles P. Watson, Consulting Geologist
Advanced Geologic Exploration/Seismo-Watch
P.O. Box 18012, Reno, Nevada 89511
Voice: 702-852-0992  /  Fax: 702-852-3226 =

mailto:watson@................
http://www.seismo-watch.com

_____________________________________________________________________

Public Seismic Network Mailing List (PSN-L)


From: Steve Hammond 
Subject: Re: Include PSN in seismic network survey?
Date: Sat, 25 Jul 1998 13:44:18 -0700

I think it is important for use to be included in this listing. We
contribute to the international record and have been contributing for
eight years. I took the liberty of going to Dave=92s WEB site and
downloading the text list of all the stations. We have the data together
it just needs to be formatted. Does anybody feel we should not submit
this to the Office of CNSS?If not I need just a little help to assemble
Dave=92s New Zealand station PSN station Site listing into the proper
format. Can you look at this URL

http://www.iris.washington.edu/manuals/acrobat/SEED_A_only.pdf

and define the shackle-ford-gundersen, Lehman, geophone <10 sec
response. I want to make sure I get it right-- And anybody with good
eye=92s might look over our station list and add other=92s like the AS-1.
Please look over these items and contribute. Also, if you don=92t want to
be included please tell me.

----Hey Larry! ---- how much data do we have on-line and off-line now? I
have 500MB or so on CD-ROM from the original BBS network.

The deadline is the end of July folks--

Regards, Steve Hammond   PSN San Jose, California



Edward Cranswick wrote:
>=20
> PSN-
>     As usual, I am passing this on a bit late, but I am still trying to
> unravel the enigmatic link or lack thereof I have with the PSN-L.  So I
> am sending this out to see our response.
> -Edward
>=20
> ********************************************************************
> Subject:
>          Request for network information
>    Date:
>          Wed, 8 Jul 1998 10:23:28 -0700 (PDT)
>    From:
>          Steve Malone 
>=20
> I have sent e-mail to all of the official CNSS network representatives
> and
> alternates regarding the need for information for an "Assessment of
> Seismic Monitoring in the US" and a contribution to an IASPEI
> publication.
> If anyone associated with a regional network who should have gotten
> this notice but did not you may find it posted on the WEB at URL:
>=20
>         http://www.cnss.org/NETS/request.survey.txt
>=20
> Please try to make sure that any seismic network you are associated wit=
h
>=20
> will be responding to this request.
>=20
>         Thanks,
>=20
>         Steve Malone                    E-mail:
> steve@......................
>         Geophysics Program              Phone: (206) 685-3811
>         University of Washington        FAX: (206)543-0489
>         Box 351650                      Office: ATG-226
>         Seattle, WA 98195       http://www.geophys.washington.edu
>=20
> --
> Edward Cranswick                Tel: 303-273-8609
> US Geological Survey, MS 966    Fax: 303-273-8600
> PO Box 25046, Federal Center    cranswick@........
> Denver, CO 80225-0046  USA      E.M. Forster said, "Only connect".
>=20
> _____________________________________________________________________
>=20
> Public Seismic Network Mailing List (PSN-L)
>=20
> To leave this list email listserver@............. with the body of the
> message: leave PSN-L

_____________________________________________________________________

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From: Greg 
Subject: Re: Papua New Guinea tsunami
Date: Sat, 25 Jul 1998 15:37:48 -0700

I noticed nobody mentioned the Tsunami Warning Center(s) yet. 

I found this site while poking around the internet today:
http://www.unesco.org/ioc/oceserv/itsu/itic.htm

Maybe the earthquake happened too close to give enough warning? There's
not really too much you can do if you have any warning, except try to
leave? If everyone knew the instant the earthquake happened that there's
was a tsunami coming would it have been enough time? I think the only
way this can be prevented is if the earthquake and tsunami are expected
well in advance of the actual event. 

,Greg

_____________________________________________________________________

Public Seismic Network Mailing List (PSN-L)


From: Jim Hannon 
Subject: Re: Papua New Guinea tsunami
Date: Sat, 25 Jul 1998 21:27:15 -0500

Mike Lozano wrote:
> 
> Charles & Meredith & everyone else,
> 
> It was with a great deal of interest that I read both of your messages.  It's so
> true that every time we see a gigantic squiggle, someone else pays the price.  I
> face the same thing in my field of meteorology.  Everytime there's a microburst
> or tornado or hail, etc.,etc... someone pays the price; but the years of
> intrepreting data and drawing conclusions has begun to pay off in the earlier
> warnings we're seeing now.  Just 2 weeks ago, the Des Moines area was hit with a
> large tornado.  Due to the early warning generated by doppler radar and
> mesoscale analysis algorithms (some of which I had a miniscule part in
> developing), no one died.  Hopefully, at some time in the future, earthquakes
> and tsunami will be as predictable.
> 
> On your other note, a few years ago, I developed a lahar warning device that is
> so cheap it's considered expendable.  It's solar charged, consumes 50
> microamperes, and is pretty much fail-safe.  I even got a patent on it (mostly
> for my own vanity), and offered it to a university (I now forget if it was the
> Univ. of Michigan) for free.  Guess what?  I never even received a reply to my
> offer.  So much for the advancement of affordable warning devices.  I hope I'm
> not stepping on any toes, but sometimes the "not invented here" syndrome is
> alive and well - unfortunately, the cost is to those who don't wind up alive and
> well.
> 
> comments?
> 
> Mikel Lozano
> -0-
I had to look up "lahar" to see what it was. :)

The death and destruction caused by human activity such as war causes me
much more pain that that caused by natural disasters.
-- 
Jim Hannon
http://soli.inav.net/~jmhannon/
42,11.90N 91,39.26W
WB0TXL


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From: S-T Morrissey 
Subject: period/mass etc of STM
Date: Sat, 25 Jul 1998 22:43:35 -0500 (CDT)

Barry,
To finally answer your question about the period adjustment of the
STM seis vs the mass. Moving the leaf spring contact point
along the boom toward the hinges does increase the period 
while requiring a slight reduction of the mass. However, the
adjustment from a period of several seconds to instability is 
only about 10 mm, so the change in the mass is relatively minor,
and was accomplished by moving the 20 gram brass trim mass.
This is because the adjustment is within the range of the 
"zero length" behavior of the spring, where the restoring
force is relatively constant over a small change of the spring
length, or opening in the case of the leaf spring.
The change in the mechanical period does affect the damping
of the VBB feedback configuration.

Regarding a change in the sensitivity with a change in the mass:
the value of the mass appears in most of the terms of the 
transfer function, so changing it does affect the shape of the overall
response. However, this effect of a 10% change on the shape of the
response is not serious. But the mass value is also part of the
constant term, so a 10% increase of the mass does produce a 10% 
increase in the output sensitivity (in volts/meter/second).

In the drawing of the seis that I have posted, the dimensions
indicated result in  a mechanical period of about 10 seconds, 
(with the base level and with the reduced dimensions of the flexures)
which is fine for a VBB feedback configuration of 90 seconds.

Regards,
Sean-Thomas

_____________________________________________________________________

Public Seismic Network Mailing List (PSN-L)


From: Edward Cranswick 
Subject: Re: is there anybody out there?
Date: Sat, 25 Jul 1998 21:58:46 -0600

Larry, John, Canie & Jim-
    Thank you for your responses which I am receiving.  However, I am not
receiving notification that my mail has been received by PSN-L nor I am
receiving the messages themselves from PSN-L that I send even though I am
receiving the messages others, e.g., like yours.
-Edward

Larry Cochrane wrote:

> Your messages are coming through just fine. Let me know if you get this.
>
> -Larry
>
> At 12:51 PM 7/24/98 -0600, you wrote:
> >Larry-
> >    I posted two messages to the PSN-L yesterday and have received no
> >acknowlegement that they were received and neither have been posted.  Is
> it me
> >or you or both of us?
> >--
> >Edward Cranswick                Tel: 303-273-8609
> >US Geological Survey, MS 966    Fax: 303-273-8600
> >PO Box 25046, Federal Center    cranswick@........
> >Denver, CO 80225-0046  USA      E.M. Forster said, "Only connect".
> >
> >
> >
> >
> >_____________________________________________________________________
> >
> >Public Seismic Network Mailing List (PSN-L)
> >
> >To leave this list email listserver@............. with the body of the
> >message: leave PSN-L
> >



--
Edward Cranswick                Tel: 303-273-8609
US Geological Survey, MS 966    Fax: 303-273-8600
PO Box 25046, Federal Center    cranswick@........
Denver, CO 80225-0046  USA      E.M. Forster said, "Only connect".




_____________________________________________________________________

Public Seismic Network Mailing List (PSN-L)


From: Edward Cranswick 
Subject: Re: cranswick@......................
Date: Sat, 25 Jul 1998 22:13:49 -0600

Bonnie-
    Thank you for your message telling me it's all OK. I have not read the
Bolt book though I have heard good things about it.  I wish I had had a copy
of it or one of his other introductory texts when I taught a course at the
American University of Armenia in Yerevan in 1992 entitled, "Introduction to
High-frequency Digital Seismic Data Acquisition, Processing and Analysis for
Strong Ground Motion Studies", that was supposed to be a warmup for the
seismology class he taught later that year.  I  drank alot of vodka instead
to try to compensate for my ignorance of some seismological fundamentals.
-Edward

bschafer@......... wrote:

> is there anybody out there?
>
> Hi, just got this message loud and clear and thought I would let you
> know.
>
> Just got a very good book written by Bruce Bolt called "Earthquakes."  A
> very good and well written book for the person who doesn't know much
> about seismology.  He had another one there but didn't have enough cash
> to get it right then.  I saw it at Borders bookstore.
>
> Bonnie
> the crafty crafter
>
> _____________________________________________________________________
>
> Public Seismic Network Mailing List (PSN-L)
>
> To leave this list email listserver@............. with the body of the
> message: leave PSN-L



--
Edward Cranswick                Tel: 303-273-8609
US Geological Survey, MS 966    Fax: 303-273-8600
PO Box 25046, Federal Center    cranswick@........
Denver, CO 80225-0046  USA      E.M. Forster said, "Only connect".




_____________________________________________________________________

Public Seismic Network Mailing List (PSN-L)


From: "Walt Williams" 
Subject: Re: Papua New Guinea tsunami
Date: Sat, 25 Jul 1998 22:56:10 +0000

Hello Mike,

Pardon my ignorance, but is a:
"lahar warning device"?

Thank you.

Walt Williams, 98.07.25
dfheli@..............
========================================

------- Forwarded Message Follows -------
Date:          Fri, 24 Jul 1998 19:05:47 -0500
From:          Mike Lozano 
Reply-to:      PSN-L Mailing List 
Organization:  Applied Sciences, Ltd.
To:            PSN-L Mailing List 
Subject:       Re: Papua New Guinea tsunami

Charles & Meredith & everyone else,

It was with a great deal of interest that I read both of your
messages.  It's so true that every time we see a gigantic squiggle,
someone else pays the price.  I face the same thing in my field of
meteorology.  Everytime there's a microburst or tornado or hail,
etc.,etc... someone pays the price; but the years of intrepreting data
and drawing conclusions has begun to pay off in the earlier warnings
we're seeing now.  Just 2 weeks ago, the Des Moines area was hit with
a large tornado.  Due to the early warning generated by doppler radar
and mesoscale analysis algorithms (some of which I had a miniscule
part in developing), no one died.  Hopefully, at some time in the
future, earthquakes and tsunami will be as predictable.

On your other note, a few years ago, I developed a lahar warning
device that is so cheap it's considered expendable.  It's solar
charged, consumes 50 microamperes, and is pretty much fail-safe.  I
even got a patent on it (mostly for my own vanity), and offered it to
a university (I now forget if it was the Univ. of Michigan) for free. 
Guess what?  I never even received a reply to my offer.  So much for
the advancement of affordable warning devices.  I hope I'm not
stepping on any toes, but sometimes the "not invented here" syndrome
is alive and well - unfortunately, the cost is to those who don't wind
up alive and well.

comments?

Mikel Lozano
-0-


_____________________________________________________________________

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_____________________________________________________________________

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From: "David A. Nelson" 
Subject: Re: (Fwd) Re: Papua New Guinea tsunami
Date: Sun, 26 Jul 1998 20:00:05 +1200

At 10:56 PM 7/25/98 +0000, you wrote:
>Hello Mike,
>Pardon my ignorance, but is a:
>"lahar warning device"?
>Thank you.
>Walt Williams, 98.07.25
>dfheli@..............


 Hi Walt,
                Lahars  =  mud flows,   usually referring to ones  from the
sides of volcanoes.
 since the loss of a passenger train and 153 lives on Xmas eve1953 when a
lahar washed out the rail bridge,   warning devices are now in place along
parts of the several rivers that come off Mt Ruapehu.   This mountain being
one of the active volcanoes in the Nth Island of New Zealand.    
   the lahar in 1953 was not caused by an eruption... rather the fragile
crater wall collapsed allowing the crater lake to partly empty as a huge mud
laden flow into the river channel down the mountain.   
   the detectors that have now been installed give early warning to road and
rail traffic approaching bridges in the area  b4 those bridges are crossed.

  dave

Co-ordinator:
New Zealand
Public Seismic Network
			Dave A. Nelson   ZL4TBN
			24 Jensen St.,   
			Green Is., Dunedin,  
			South Is.. New Zealand.  

http://psn.quake.net/dave/home.htm   

IF there indeed are other parallel universes... I can now rest in the
knowledge, that in at least one of them, I am filthy rich and drive a red
Ferrari


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From: Bob Fryer 
Subject: Re: Papua New Guinea tsunami
Date: Sun, 26 Jul 1998 01:12:54 -0700

Hello Greg,

For those within 50 to 100 miles of a quake, the quake itself is the
warning.  On July 12, 1993 at Okushiri Island, Japan, an M7.8 struck 44
miles offshore.  Many of those who immediately headed for high ground from
the fishing port of Aonae were spared from the tsunami which first struck
about 5 minutes later, as warnings were being issued on Hokkaido.  At least
160 people died on the island, including the 35 fatalities in a hotel
struck by a landslide.

A major complication in the New Guinea event was that many of the villages
were on a sand spit -- there was no escape.

The town of Seaside, Oregon faces a similar problem -- the bridges needed
for escape will likely be destroyed by the quake which is expected sometime
in the next hundred years.  Wide areas of the Northwest coast, from
northern California to Vancouver Island, were inundated by the massive
tsunamis generated by the estimated M9.2 quake in January of 1700.  The
expected quake will likely range from M8.0 to 8.5.

Bob Fryer  -- on the Cascadia Subduction Zone


>I noticed nobody mentioned the Tsunami Warning Center(s) yet.
>
>I found this site while poking around the internet today:
>http://www.unesco.org/ioc/oceserv/itsu/itic.htm
>
>Maybe the earthquake happened too close to give enough warning? There's
>not really too much you can do if you have any warning, except try to
>leave? If everyone knew the instant the earthquake happened that there's
>was a tsunami coming would it have been enough time? I think the only
>way this can be prevented is if the earthquake and tsunami are expected
>well in advance of the actual event.
>
>,Greg

----- earthquake WARNING research -----
--- animals, people, scientific evidence ---
---  http://www.teleport.com/~bfryer ---



_____________________________________________________________________

Public Seismic Network Mailing List (PSN-L)


From: barry lotz 
Subject: Re: period/mass etc of STM
Date: Sun, 26 Jul 1998 06:56:11 -0700

S-T Morrissey wrote:
Sean Thomas
   Thanks for getting back to me. Last week I ran a calibration on my
capacitive displacement transducer and the sensitivity was high and
linear. the problem I had was over a 20+ sec the output would drift. It
might have been mechanical but it seemed more like electrical. I am
trying an LVDT now. There was a thread back a while regarding LVDT vs
Capacitive sensor verses VRDT. I can't remember the particular result of
that discussion. I will get around to testing all three to convince
myself which works for me. I'm trying to keep the electronics as simple
as possible and yet get the sensitivity. I haven't looked at your recent
updated site yet. Looking forward to it.
                                        
Regards                               
                                         Barry

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Public Seismic Network Mailing List (PSN-L)


From: barry lotz 
Subject: Re: Papua New Guinea tsunami
Date: Sun, 26 Jul 1998 07:03:40 -0700

Bob,Greg
   I think Hawaii have a similar warning system when a large event is
recorded from around the rim.
                          Barry

Bob Fryer wrote:
> 
> Hello Greg,
> 
> For those within 50 to 100 miles of a quake, the quake itself is the
> warning.  On July 12, 1993 at Okushiri Island, Japan, an M7.8 struck 44
> miles offshore.  Many of those who immediately headed for high ground from
> the fishing port of Aonae were spared from the tsunami which first struck
> about 5 minutes later, as warnings were being issued on Hokkaido.  At least
> 160 people died on the island, including the 35 fatalities in a hotel
> struck by a landslide.
> 
> A major complication in the New Guinea event was that many of the villages
> were on a sand spit -- there was no escape.
> 
> The town of Seaside, Oregon faces a similar problem -- the bridges needed
> for escape will likely be destroyed by the quake which is expected sometime
> in the next hundred years.  Wide areas of the Northwest coast, from
> northern California to Vancouver Island, were inundated by the massive
> tsunamis generated by the estimated M9.2 quake in January of 1700.  The
> expected quake will likely range from M8.0 to 8.5.
> 
> Bob Fryer  -- on the Cascadia Subduction Zone
>

_____________________________________________________________________

Public Seismic Network Mailing List (PSN-L)


From: Greg 
Subject: Re: Papua New Guinea tsunami
Date: Sun, 26 Jul 1998 11:22:07 -0700

barry lotz wrote:
 
> Bob,Greg
>    I think Hawaii have a similar warning system when a large event is

http://www.unesco.org/ioc/oceserv/itsu/itic.htm

The link I sent to the list is for the International Tsunami Information
Center (ITIC) is in Hawaii. I think there is also a U.S. only Tsunami
Warning Center in Hawaii. I found links for one in Alaska and one in
British Columbia. There was also something about Kamchatka, but I don't
remember. I wouldn't doubt that Japan has it's own as well. My guess is
they all coordinate with the international one. Not to sound too
insulting but there are lots of typos on the page and it hasn't been
updated since November 1996. 

Pacific Tsunami Warning Center
91-270 Fort Weaver Road
Ewa Beach, Oahu, HI 96706

International Tsunami Information Center
737 Bishop Street, Suite 2200
Honolulu, HI 96813-3213

,Greg

_____________________________________________________________________

Public Seismic Network Mailing List (PSN-L)


From: Karl Cunningham 
Subject: Re: STM-8 drawings
Date: Sun, 26 Jul 1998 12:47:52 -0700

Sean-Thomas --

I downloaded the new drawings on your STM-8.  They look great!  To view
them, I saved the images to disk and printed them with LView (a shareware
graphics program).  Printed at 600dpi, there is very little loss in quality
and they are quite easily read.

Thank you for taking the time to make these drawings and making them
available to us.

Karl Cunningham
La Mesa, CA.
PSN Station #40
karlc@.......


At 08:17 PM 7/24/98 -0500, you wrote:
>I have finally posted the latest drawings of the hardware-
>store seismometer on the web site at:
>
>http://www.eas.slu.edu/People/STMorrissey/index.html
>
>under the "figures and drawings" page. The seismometer
>drawings are of two dimensions only; the overhead view
>can generally be deduced from the side view because of
>the natural symmetry of the design.


_____________________________________________________________________

Public Seismic Network Mailing List (PSN-L)


From: Ted Blank 
Subject: Re: [Fwd: Santa Cruz Seismic Instruction Software]
Date: Sun, 26 Jul 1998 18:22:41 -0700 (PDT)


I will speak to my son's science teacher.  When I mentioned it to her 
last year she was very excited about the idea.  Thanks for proposing to 
sponsor us.  



Ted Blank
San Jose, California

On Thu, 23 Jul 1998, Edward Cranswick wrote:

> 
> 
> --
> Edward Cranswick                Tel: 303-273-8609
> US Geological Survey, MS 966    Fax: 303-273-8600
> PO Box 25046, Federal Center    cranswick@........
> Denver, CO 80225-0046  USA      E.M. Forster said, "Only connect".
> 
> 
Jan-
	I thought that you, Steve, and Ted might do something, and I think that
I forwarded some kind of info to the PSN-L.  However, I was not really
connected with it myself, and I wasn't going to try to tell you guys
what you should do (what maybe I should have helped to do myself).  In
any case, the IRIS meeting does not get as much coverage as the AGU
meetin in San Francisco in December which Larry and Ted attended last
year with me.  So I think it would be a great idea to pursue the idea
that you and Ted talked about last year of having a bunch of students
submit a poster for the AGU meeting 6-10 December this year
. You guys can write the
abstract and prepare the poster and I, as an AGU member, can sponsor it
and get the USGS to pay for it. The abstract deadline for that is: 

	August 26, 1998		(Postal/express mail submissions)

        September 2, 1998	(Interactive Web Form submissions) 

	Because we only have about a month, please let me know ASAP what you
think and also CC a copy to me at  which what
I am trying to make my address for PSN-related activities.
-Edward

Jan Froom wrote:
> 
> It's a shame that we couldn't have gone to this conference, since I think
> Steve, Ted & I  are about the only ones in this area that are actually working
> with schools.... well Elementary, Middle & High.  I tried, and got a note from
> a lady in Arizona that forwarded my request to a lady in Santa Cruz....  but
> after that I got no answer.
> ---------------------- Forwarded by Jan Froom/San Jose/IBM on 07-22-98 11:26 AM
> ---------------------------
> 
> Ted Blank
> 07-21-98 01:13 PM
> To: Jan Froom/San Jose/IBM@IBMUS
> cc:
> From: Ted Blank/Santa Teresa/IBM @ IBMUS
> Subject: Re: Santa Cruz Seismic Instruction Software
> 
> I tried to get the information from Larry but it was all very vague.  Finally
> he called me the night before to say it was the next day but by that time I had
> other plans.  Oh well.
> 
> Regards, Ted
> DB2 Performance, IBM Santa Teresa Lab, San Jose, California
> 
> Ted Blank/Santa Teresa/IBM .....(from Notes)
> IBMUSM50(TED) .............................(from PROFS/VM)
> ted@.......... ..............................(from internet sites)
> STLVM6(BLANK) .............................(for LIST3820 files etc.)
> Tie: 8-543-3589    Ext:  (408) 463-3589   Fax:  (xxx-2614)

-- 
Edward Cranswick                Tel: 303-273-8609
US Geological Survey, MS 966    Fax: 303-273-8600
PO Box 25046, Federal Center    cranswick@........
Denver, CO 80225-0046  USA      E.M. Forster said, "Only connect".


From: Peter 
Subject: Re: Papua New Guinea tsunami
Date: Sun, 26 Jul 1998 23:32:14 -0700

Here is a page that has a cheap warning device, I don't know if it would
work in some cases?

http://www.pacifier.com/~sunmanh/edd_tws.html

Pete Fleming


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Public Seismic Network Mailing List (PSN-L)


From: lahr@..................
Subject: Re: Papua New Guinea tsunami
Date: Mon, 27 Jul 1998 10:39:15 -0600 (MDT)

Pete,

I would say that the device is of no help!  Where the ball would fall, if indeed
the ball of the entire divice didn't land on the floor, would depend on the focal 
mechanism of the earthquake.  If the EQ is offshore and the first motion at the home is a 
compression, then the ground would move up and landward.  If the first motion was
a dilation, then the ground would move down and seaward.  Therefore, the direction
the ball falls would not give information about the location of the earthquake.

If I were located at sea level in a tectonically active area, I would head for high
ground right after feeling a strong earthquake.  It could be a false alarm, but
why take a chance?

JCLahr
################################## John C. Lahr
################################# Seismologist
################################ U.S. Geological Survey
############################### Geologic Hazards Team, MS966
############################## PO Box 25046
#############################/##############################
############################/###############################
Denver, Colorado 80225-0046 ################################
    Phone: (303) 273-8596 ##################################
     Fax: (303) 273-8600 ###################################
         lahr@........ #####################################
                http://giseis.alaska.edu/lahr
               http://lahr.org/john-jan


> Date: Sun, 26 Jul 1998 23:32:14 -0700
> From: Peter 
> 
> Here is a page that has a cheap warning device, I don't know if it would
> work in some cases?
> 
> http://www.pacifier.com/~sunmanh/edd_tws.html
> 
> Pete Fleming
> 
> 
> _____________________________________________________________________
> 


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Public Seismic Network Mailing List (PSN-L)


From: "Walt Williams" 
Subject: PSN-L: Papua New Guinea tsunami
Date: Mon, 27 Jul 1998 10:32:54 +0000

Hello Greg and All,

Recently presented on the 'Discovery Channel' was a three hour 
show about Tsunamis, their destructive power, warning systems, 
mechanical tsunami break-wall systems (Japan). Japan does have full 
time tsunami center. I did not view the beginning nor the end of the 
show. It was an excellent presentation. I am in the Los Angeles area, 
and the show was last month.

Walt Williams, 98.07.27 
=========================================================


------- Forwarded Message Follows -------
Date:          Sun, 26 Jul 1998 11:22:07 -0700
From:          Greg 
To:            PSN-L Mailing List 
Subject:       Re: Papua New Guinea tsunami
Reply-to:      PSN-L Mailing List 

barry lotz wrote:

> Bob,Greg
>    I think Hawaii have a similar warning system when a large event is

http://www.unesco.org/ioc/oceserv/itsu/itic.htm

The link I sent to the list is for the International Tsunami
Information Center (ITIC) is in Hawaii. I think there is also a U.S.
only Tsunami Warning Center in Hawaii. I found links for one in Alaska
and one in British Columbia. There was also something about Kamchatka,
but I don't remember. I wouldn't doubt that Japan has it's own as
well. My guess is they all coordinate with the international one. Not
to sound too insulting but there are lots of typos on the page and it
hasn't been updated since November 1996. 

Pacific Tsunami Warning Center
91-270 Fort Weaver Road
Ewa Beach, Oahu, HI 96706

International Tsunami Information Center
737 Bishop Street, Suite 2200
Honolulu, HI 96813-3213

,Greg

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From: Hubert Vroomen 
Subject: Re: period/mass etc of STM
Date: Mon, 27 Jul 1998 13:49:35 +0200

Dear Sean-Thomas and others,

I have been following the discussion around the development of the STM-8
with great interest. Altough not actively involved in real seismology
(neither as an amateur nor professional, yet), I am interested in its
aspects of precise instrument construction. I have been involved however,
for a very short period, in gravity measurement and the development of an
airborne gravimeter based on the GWR superconducting gravimeter.=20

(By the way, if someone happens to have some information or even a (copied)
handbook of a Askania/Bodenseewerke GSS2 or GSS-20 ship-borne gravimeter,
which she/he could make available to me, I would be much obliged. I have
such a piece of mechanical art here and besides a cruel electrical
schematic I have almost no substantial information on the beast (if someone
is interested, I can give more information in a later post).)

But now for the reason of this post. I have been thinking about the
possibilities of recentering the STM-8 beam, as the method you proposed,
using a thread with a small weight, seems to me not the most elegant way. I
would think, that a method that is not using some moving parts on the beam
would be preferred above a method which is. Your post on the adjustment of
the period brought me the following idea:

If you could change the moment of the spring-force, which you are doing
when changing the point of attachment of the spring along the beam, one
would be able to recenter. To even improve the elegance of the system, one
could try to change the position of the attachment to the BASE, instead of
changing its BEAM-position. Doing this with a slow, gentle motion would
result in a (possible) elegant way of recentering.

I have thought of using a piece of aluminium wire or rod for this, and
using a controlled current through it to control its temperature and
therewith the length of the part, which can be used (either direct or via a
lever-system) to change the base-position of the spring. But after some
after-tought :-), I came to the conclusion that using a
differential-temperature actuator in a temperature sensible system like a
seismometer would not be the smartest idea, but the basic priciple stands,
and one could try to use a small electric motor to change the position as
well.

In fact, one could also use the spring itself as an actuator as well,
running some fine heating wires along the spring-surface, but I could
imagine that the resulting differential movement of these wires along the
surface could result in substantial damping, which is not good off-course.

I must admit, that the overall design and concept of the STM-8 amazes me
because of its simple and natural beauty, and putting an electrical motor
on the beam seems to me like putting a ski-rack on a Porsche (or, for you
US-guys, on a Camaro). That is the reason I came up with this new
recentering concept. I have no proof of it being better (or worse), just my
intuition as a mechanical engineer and precision instrument freak. I have a
lot of other potential ideas in which to improve the STM-design in detail,
but the basic thought behind it is just marvelous and could really bring
amateur-seismology a lot further.

Just some of my neurons that didn't want to sit still,

Hubert


Ir. Hubert Vroomen
Heinz Nixdorf Institut
Universit=E4t-GH Paderborn
Paderborn, Germany

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From: lahr@..................
Subject: Re: PNG Tsunami
Date: Mon, 27 Jul 1998 12:43:59 -0600 (MDT)

Speaking of the PNG disaster, I just received this Email message and decided
to send a small check. 

JCLahr

Better to light a candle than to curse the darkness.

> ===============$$$$$$$$$$$$$$$$$===============###############========@@@@
> 
> Date: Mon, 27 Jul 1998 11:35:15 -0400
> From: Rick Wunderman 
> Subject: [NAT-DSR:452] Papua New Guinea: Tsunami [PNG Embassy: 23-Jul-98]
> To: jon.fink@.......
> 
> >Subject: [NAT-DSR:452] Papua New Guinea: Tsunami [PNG Embassy: 23-Jul-98]
> >
> >Embassy of Papua New Guinea
> >Washington, DC
> >Disaster Relief Fund Appeal
> >23 July 1998
> >
> >
> >Dear Friends/Wantoks/Relatives of Papua New Guinea
> >
> >You would have already been informed through the international media
> >on the tsunami (tidal wave) which brought catastrophe upon three
> >Aitape sub-district villages in the northwestern part of Papua New
> >Guinea on the night of Friday, July 17, 1998.  The Embassy of Papua
> >New Guinea staff and their families are saddened by this latest
> >tragedy and are appealing for combined prayers and support for those
> >country-folks affected.
> >
> >
> >GENERAL BACKGROUND
> >
> >The tsunami, in three successions of waves towering approximately 30
> >feet (10 meters), resulted from a 7.0 magnitude shallow underwater
> >earthquake 18 miles (30 Kilometers) off the coast.  The three
> >villages, Arop, Nimas, and Waropu were completely destroyed whilst
> >neighboring Sissano, Malol, Aitape, and seven others received
> >extensive damages.
> >
> >Unofficial death toll stands at approximately 700 with possible
> >figures reaching between 2500 and 3000.  The three devastated
> >villages have a population of over 8000 inhabitants and thus far 6000
> >are unaccounted for. Reports received indicated that the elderly and
> >children were mostly killed in the disaster.
> >
> >The tsunami is the latest of a series of natural disasters striking
> >Papua New Guinea in the last three and a half years.  The volcano
> >eruption in Rabaul, cyclone Justin's destruction in the Milne Bay
> >area, and the El Nino-induced drought in most parts of the country,
> >have caused a horrendous burden on the Government and the people of
> >Papua New Guinea.
> >
> >
> >CURRENT RELIEF OPERATIONS
> >
> >At present, the Government, with assistance from the Australian and
> >New Zealand Defence forces, are working around the clock to bring
> >relief supplies and medical attention to the affected areas.  Relief
> >efforts are currently at phases one and two of the post-disaster
> >exercise.
> >
> >Phase one efforts include identifying the missing, recovering bodies,
> >cremation or burial, and evacuating survivors to medical centers.
> >Phase two will be to deal with the traumatized survivors and
> >relatives, and to sanitize the affected areas from diseases resulting
> >from the tsunami.  Concurrent on- site medical attention and
> >evacuation of survivors and villagers from nearby are part of the
> >phase two exercise.
> >
> >
> >EMBASSY OF PAPUA NEW GUINEA RELIEF FUND
> >
> >The Embassy is embarking, through this letter, to announce its relief
> >assistance efforts from the Americas by setting up a disaster relief
> >account to solicit donations for the people of Aitape sub-district
> >who are currently in distress.  The funds will assist in phase three
> >of the relief exercise which will include resettling of survivors
> >into new village dwellings and assisting them rebuild their lives.
> >Donations should be made to:
> >
> >               "Aitape Disaster Relief Fund"
> >               The Embassy of Papua New Guinea
> >               1615 New Hampshire Avenue, N.W.
> >               Suite 300
> >               Washington D.C., 20009
> >               United States of America
> >
> >
> >Due to the Embassy's incapacity to receive and handle volumes of
> >relief materials and supplies, it is requesting individual and group
> >donors to channel their items through legitimate or qualified
> >international organizations such as the Red Cross (in the U.S. and
> >Canada), Counterpart International Inc., Doctors Without Borders,
> >Habitat for Humanity, Oxfam America, Project Hope, and others.  The
> >materials and supplies referred to include shelter, medical supplies,
> >clothing, sanitary water, and logistic systems.  Specialists such as
> >doctors, trauma counselors, and other humanitarian-related agencies
> >willing to provide services, should also seek programs that are
> >sponsored by these organizations.
> >
> >
> >CONTACTS FOR DISASTER RELIEF EFFORTS
> >
> >The Embassy of Papua New Guinea's contacts on the relief exercise is
> >Mr Graham Michael, Counsellor, and Ms. Barbara Age, Second Secretary.
> >They will be available to facilitate any enquiries on relief efforts
> >and donations, provide media guidance on the latest, and co-ordinate
> >with international disaster relief organizations on programs
> >associated with the Aitape disaster. They can be reached on
> >Ph: 202 745 3680, Fax: 202 745 3679, or through
> >E-Mail: kunduwash@.......
> >
> >The Embassy will keep you updated should further information becomes
> >available.
> >
> >
> >
> >H.E. Nagora Y. Bogan, KBE
> >Ambassador
> >
> >
> >
> >
> >distributed by
> >- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
> >Volunteers in Technical Assistance
> >Disaster Information Center                   lists: listproc@........
> >                                                     sitreps   nat-dsr
> >      web: www.vita.org                              appeal    fireline
> >- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
> >comments/suggestions/requests to incident@........
> ###########################################################################
> 


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From: Ashley Neal Hornbeck 
Subject: What is the destructive range of an earthquake?
Date: Mon, 27 Jul 1998 15:43:42 -0500

Hello All,

I'm one of the silent reader of this list.  I've lived in Texas my entire
life.  Because I have practically no experience with earthquakes I have a
question.

Is there a rule-of-thumb attenuation equation for earthquakes?

In other words:
If I'm x miles away from the epicenter of M7.0.
That would be equivalent to being directly above the epicenter of a M y.
Where:
 x is distance
 y is magnitude

While this may not be the proper way of describing the force at some
distance, x, away from the epicenter I believe you can understand my question.

Would someone mind helping with this?

Thanks,
Ash

 -----------------------------------------------
| Ashley Neal Hornbeck - Hornbeck@............. |
 -----------------------------------------------
| iiSys Corporation                             |
| 12777 Jones Road, Suite 195                   |
| Houston, TX  77070                            |
 -----------------------------------------------
| (281) 894 1674                                |
 -----------------------------------------------

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From: Edward Cranswick 
Subject: Re: Include PSN in seismic network survey?
Date: Mon, 27 Jul 1998 17:14:10 -0600

Steve-
    I agree with you, I admire your energy, and by coincidence, I received
another request for this information today from Steve Malone (see below).  I
think it would be a good idea to include the PSN info in the CNSS directory as
you and he both suggest because it will give the PSN more access to the world,
and the vice versa; that I think is one of the main rationales for the PSN in
the first place.
-Edward

*********************************************************************
[Steve Malone wrote:]

        Also, on a different subject, since I know you are interested and
involved in the Peoples Seismograph Network I have a question.  I have
been tasked with doing an inventory of seismic networks in the US and am
getting a response from most of the regional networks (ie members of the
CNSS).  The `PSN' has never been an actual part of the CNSS since it is a
pretty ad hoc group with no central authority (as it should).  However,
for this inventory (and maybe just to increase its visability it might be
nice to include stations form the PSN in what I am doing.  You may find a
descritpion of what I need on the WEB at:
        http://www.cnss.org/NETS/request.survey.txt

Any ideas you might have on how I could do this, please let me know.


        Steve Malone                    E-mail: steve@......................
        Geophysics Program              Phone: (206) 685-3811
        University of Washington        FAX: (206)543-0489
        Box 351650                      Office: ATG-226
        Seattle, WA 98195       http://www.geophys.washington.edu

*********************************************************************

Steve Hammond wrote:

> I think it is important for use to be included in this listing. We
> contribute to the international record and have been contributing for
> eight years. I took the liberty of going to Dave’s WEB site and
> downloading the text list of all the stations. We have the data together
> it just needs to be formatted. Does anybody feel we should not submit
> this to the Office of CNSS?If not I need just a little help to assemble
> Dave’s New Zealand station PSN station Site listing into the proper
> format. Can you look at this URL
>
> http://www.iris.washington.edu/manuals/acrobat/SEED_A_only.pdf
>
> and define the shackle-ford-gundersen, Lehman, geophone <10 sec
> response. I want to make sure I get it right-- And anybody with good
> eye’s might look over our station list and add other’s like the AS-1.
> Please look over these items and contribute. Also, if you don’t want to
> be included please tell me.
>
> ----Hey Larry! ---- how much data do we have on-line and off-line now? I
> have 500MB or so on CD-ROM from the original BBS network.
>
> The deadline is the end of July folks--
>
> Regards, Steve Hammond   PSN San Jose, California
>
> Edward Cranswick wrote:
> >
> > PSN-
> >     As usual, I am passing this on a bit late, but I am still trying to
> > unravel the enigmatic link or lack thereof I have with the PSN-L.  So I
> > am sending this out to see our response.
> > -Edward
> >
> > ********************************************************************
> > Subject:
> >          Request for network information
> >    Date:
> >          Wed, 8 Jul 1998 10:23:28 -0700 (PDT)
> >    From:
> >          Steve Malone 
> >
> > I have sent e-mail to all of the official CNSS network representatives
> > and
> > alternates regarding the need for information for an "Assessment of
> > Seismic Monitoring in the US" and a contribution to an IASPEI
> > publication.
> > If anyone associated with a regional network who should have gotten
> > this notice but did not you may find it posted on the WEB at URL:
> >
> >         http://www.cnss.org/NETS/request.survey.txt
> >
> > Please try to make sure that any seismic network you are associated with
> >
> > will be responding to this request.
> >
> >         Thanks,
> >
> >         Steve Malone                    E-mail:
> > steve@......................
> >         Geophysics Program              Phone: (206) 685-3811
> >         University of Washington        FAX: (206)543-0489
> >         Box 351650                      Office: ATG-226
> >         Seattle, WA 98195       http://www.geophys.washington.edu
> >
> > --
> > Edward Cranswick                Tel: 303-273-8609
> > US Geological Survey, MS 966    Fax: 303-273-8600
> > PO Box 25046, Federal Center    cranswick@........
> > Denver, CO 80225-0046  USA      E.M. Forster said, "Only connect".
> >
> > _____________________________________________________________________
> >
> > Public Seismic Network Mailing List (PSN-L)
> >
> > To leave this list email listserver@............. with the body of the
> > message: leave PSN-L
>
> _____________________________________________________________________
>
> Public Seismic Network Mailing List (PSN-L)
>
> To leave this list email listserver@............. with the body of the
> message: leave PSN-L



--
Edward Cranswick                Tel: 303-273-8609
US Geological Survey, MS 966    Fax: 303-273-8600
PO Box 25046, Federal Center    cranswick@........
Denver, CO 80225-0046  USA      E.M. Forster said, "Only connect".




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From: S-T Morrissey 
Subject: centering and temp comp of STM seis
Date: Mon, 27 Jul 1998 18:27:59 -0500 (CDT)

Hubert,
Thanks for your observations about the recentering of the STM-8
vertical seis. I do believe that using a small DC (9volt,5 ma)
gearmotor (2 RPM) (Edmund Scientific number 41331, $25) to
turn a thin threaded rod (6-32) attached to its output shaft 
to translate a small mass (10grams, with a larger 10-32 hole)
in parallel with the boom is going to be hard to beat for elegance
and simplicity. I wouldn't worry about the asthetics of it any
more than I worried about the ski rack on the back of my old
'70 Corvette: one has to do what has to be done. And the motor
and shaft are completely passive when not in use. A full scale
recentering takes about 5 minutes, introducing about 50 milliwatts
of heat in the motor case, which I do not think I can later see
in the output. I guess I need to get a photo of it to the web site.

The motor is just about balanced at its mounting flange with the 
weight of the 10 cm stainless steel or brass shaft extension ,
so mounting it to a corner of the aluminum angle at the moving side 
of the main hinges only slightly increases the moment of the boom.
This reduces the effective "reduced pendulum" length ( where not all 
the mass is at the end as in an ideal pendulum) which slightly 
shortens the mechanical period. Since this is a VBB fedback
system, this slightly affects the damping term.  However, the effect 
IS slight, and the change is not observable above the noise in the 
output of a step calibration with the sensor operating at 90 seconds. 

And the adjustment of the period itself is really not critical,
with 6 to 10 seconds being a convenient value. Longer mechanical periods
are more unstable, which adds to the thermal problem of the large
leaf spring, which currently contributes about 200 microns of 
displacement (at the VRDT) per degree C with the feedback off. 
This is about ten times the effect calculated from the thermal
coefficients of the hinge support, VRDT and vane support, etc.

This temperature effect of the leaf spring is still a serious 
problem that needs to be solved in an elegant way. An additional 
complexity is that the spring has what might be called a negative 
thermal coefficient. Ie, it gets stiffer with a temperature decrease, 
which raises the boom.  This would suggest that some thermo-elastic 
elememt that contracts when cooled could be used to compensate the 
expansion of the leaf spring. I am currently experimenting with
a very fine coil spring (100 turns wound at 5mm diameter of #36 drawn
copper) installed from the boom to the base. It is too early to
determine its effectiveness. 

The only really successful thermal compensation has been electronic,
 using the LM35 thermometer chip and the 25-turn auxillary coil
 at the magnet. This can contribute noise in the passband, so it
 is low-pass filtered at 5000 seconds. It is another complication
 though, with additional electronics, and not the "set it and 
 forget it" compensation that I would prefer.

 Regards,
 Sean-Thomas


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From: meredith lamb 
Subject: More surplus geophones & etc.
Date: Mon, 27 Jul 1998 18:07:52 -0600

Hi all,

My brother Robert (Bob) has alerted me to a new geophone source
(I think,... besides Gateway & Startronics in recent past).

http://www.allcorp.com/

The web site seems to cover alot of territory over other surplus
sources.  Magnets (afew 1/4" thick variety neo....cheap
compared to alot of other sources...if you don't have any, this
is the place to buy).  Looks like 2 pole & likely 4 pole varietys
per catalog. Relays etc, etc., 96 pages catalog which
you can download via free acrobat reader (3.191 meg for catalog).
Or you can request a mail copy per site.

Anyway...the geophone (pg 96), cat GP-1, $8.00 plus minimum
of $5.00 shipping and handling; doesn't go into details, nor is
there any indication they are all the same model (presumed).
LED indicator circuit schematic enclosed, which Bob says works.
Foreign purchase ok, if drawn on U.S. bank...see details.

Bobs purchase geophone was a 10hz, 600 ohm, which he
claims are much more sensitive than the Startronics (Arizona) model
(14hz) ...roughly by ~8X signal.  Size, 1.6" height X 1.2" diameter.
Bob is a retired electronics engineer.

Visit the web site for more info.  Los Angeles & Van Nuys, California
stores.

I think this surplus source has been around for quite a number of years,
but I've never bought anything from them myself.  Bob has several
times, so I presume they are OK.

Am no geophone user myself, strictly teleseimometrist....unless I
lived in California, or was visiting Yellowstone National Park-ha.

Meredith Lamb


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From: S-T Morrissey 
Subject: eq magnitude range
Date: Mon, 27 Jul 1998 19:17:43 -0500 (CDT)

Ash,

What you feel from a given quake of a given size depends on
what part of the country you live in and what your local geology
consists of. There are really no exact formulas, and the matter
is complicated by the use of two (in general) earthquake scales.

The Richter scale indicates the total energy released by an event,
and generally everyone gets the same magnitude from their seismic
data regardless of their distance from the quake (unless, of course,
they are in dire need of funding, which moves the quake closer to
their area of study and increases the magnitude.) Magnitudes do not
relate directly to what is felt because a deep earthquake will be
felt weakly over a larger area that a stronger shallow event. Several
years ago there was a large (7.0+)  quake 600 km deep below Bolivia
that was felt from Panama to Buenos Aires, but did little damage.
Magnitudes are listed as arabic numbers with a decimal point, eg 5.5.

The Mercalli intensity scale relates what physically happens in
the epicenter area, from a MMI of being sensed by sensitives to
a MMXII being total devastation. It is pretty subjective, and needs
input of local geology, what the local population has recently
inhaled, etc, to relate it to the Richter magnitude.
(There is a listing of it on our Earthquake Center web site,
//www.eas.slu.edu/Earthquake_Center/mercalli.html).
Intensities are listed as Roman numerals, with no decimal point.

Here in the USA, it generally takes a (Richter) magnitude 3.0 to
be felt, and a 5.0 to throw things off shelves in the epicentral area,
a 6.0 to crack buildings and bridges, and a 7.0 to throw them down.

But if you are not at the epicenter, then local and regional geology
will control the Mercalli intensity you feel. Here in the midwest, a
magnitude 5 can be felt over 100 km away, but in California, in the 
mountainous regions, it may only be felt 10 km away , and even less
near the freeways. But often the most destruction (higher intensity)
is in soft alluvial valleys, which amplify the ground motion, as in
Mexico city,  and the areas near the San Francisco bay in the Loma 
Prieta quake several years ago. In the Aleutians, we could feel
magnitude 4.0 events 50 km away because of the solid volcanics.

Regards,
Sean-Thomas

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From: Fred S 
Subject: Re: Papua New Guinea tsunami
Date: Mon, 27 Jul 1998 17:40:00 -0700

Pete,  This reminds me of a device I saw in a history book used in China
around 1200AD.  A ball would drop in the oppisite direction. Pretty cool
idea for such a long time ago.

-- 
Gravity:  It's not just a good idea.  It's the LAW !

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From: barry lotz 
Subject: Re: centering and temp comp of STM seis
Date: Mon, 27 Jul 1998 16:58:04 -0700

Sean Thomas
 $0.02
   It has been my belief that besides the possible affect of temperature
on the spring length/stiffness,  the main reason that the beam moved up
was that the air is more dense at lower temperatures. Since the bouyancy
force is the weight of the medium displaced there is a larger bouyancy
force at lower temperatures.

                                      Barry

PS I found the approximate volume of my sensor using the unit weight of
aluminum. I then calculated the uplift(air density change) for a 10
degree temperature change. For a given temperature change I measured the
voltage change(drift)of my sensor. It agreed  reasonably well with the
vts/gm calibration factor I had obtained previously.


>S-T Morrissey wrote:
> ....
> This temperature effect of the leaf spring is still a serious
> problem that needs to be solved in an elegant way. An additional
> complexity is that the spring has what might be called a negative
> thermal coefficient. Ie, it gets stiffer with a temperature decrease,
> which raises the boom.

_____________________________________________________________________

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From: "Walt Williams" 
Subject: PSN-L: (Fwd) More surplus geophones & etc.
Date: Mon, 27 Jul 1998 18:30:43 +0000

Hi Meredith & All,

I recently bought several Geosource MD-81, 10 Hz geophones from the
Van Nuys, California, USA, store. They are packaged exactly the same
as the Gateway supplier, but are slightly less expensive. Mostly
same type. They have same diagram and a little perfboard with a LM393
quad comparator and some resistors. You solder together to make
simple circuit with red LED.

I put my Tek-465B with x1 probe, 5 mv channel setting directly on
geophone pins, place on rug (simple low-pass filter :-), lots of 60
Hz, but works pretty good! I can see cars and trucks passing maybe
60 meters from house. Can see cat walking in kitchen, making din din
run -- no amplifier, surprisingly sensitive! One of the nice folks 
(Roger Sorenson) on PSN sent me TurboCAD layout for geophone amp he 
built, I have hacked that up and made a simple test circuit, works 
well. This is very interesting, lots of good ways to spend boring 
nights!

Cheers,

Walt Williams, 98.07.27
dfheli@..............

------- Forwarded Message Follows -------
Date:          Mon, 27 Jul 1998 18:07:52 -0600
From:          meredith lamb 
To:            psn-l mailing list 
Subject:       More surplus geophones & etc.
Reply-to:      PSN-L Mailing List 

Hi all,

My brother Robert (Bob) has alerted me to a new geophone source
(I think,... besides Gateway & Startronics in recent past).

http://www.allcorp.com/

The web site seems to cover alot of territory over other surplus
sources.  Magnets (afew 1/4" thick variety neo....cheap
compared to alot of other sources...if you don't have any, this
is the place to buy).  Looks like 2 pole & likely 4 pole varietys per
catalog. Relays etc, etc., 96 pages catalog which you can download via
free acrobat reader (3.191 meg for catalog). Or you can request a mail
copy per site.

Anyway...the geophone (pg 96), cat GP-1, $8.00 plus minimum
of $5.00 shipping and handling; doesn't go into details, nor is
there any indication they are all the same model (presumed).
LED indicator circuit schematic enclosed, which Bob says works.
Foreign purchase ok, if drawn on U.S. bank...see details.

Bobs purchase geophone was a 10hz, 600 ohm, which he
claims are much more sensitive than the Startronics (Arizona) model
(14hz) ...roughly by ~8X signal.  Size, 1.6" height X 1.2" diameter.
Bob is a retired electronics engineer.

Visit the web site for more info.  Los Angeles & Van Nuys, California
stores.

I think this surplus source has been around for quite a number of
years, but I've never bought anything from them myself.  Bob has
several times, so I presume they are OK.

Am no geophone user myself, strictly teleseimometrist....unless I
lived in California, or was visiting Yellowstone National Park-ha.

Meredith Lamb


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From: meredith lamb 
Subject: MEK to remove glue
Date: Mon, 27 Jul 1998 20:44:54 -0600

Hi All,

Bob Lamb recently suggested using MEK solvent to assist in
dissolving glue holding magnets and metal washers from speakers;
and of course for other parts desired.  It will remove paint and
ruin plastic of course.

Bob Lamb:  "Over the years I have had alot of success with "MEK"
solvent - especially leaving things for a day or so; even softens some
epoxy-like cements.  Very volatile bad stuff, so its a strictly a
outdoors use item, with a breeze in the right direction."  Keep out
of reach of children, pets, etc.   "MEK, is the same ingredient in
PVC cement."

The original goal was too remove a ring or donut ferrite magnet
from a speaker magnet assembly, for possible further machining.
The item I tried it with was a broken Radio Shack speaker,
originally for the STM-8 vertical seismometer.  After 3 days of
soaking, it was apparent that the fluid was not penetrating very
well, as it still could not be removed.  It may work if its allowed
to soak for a much longer period of indeterminate time.  The
visual side glue was softened within hours and easily was removed.
No harm was done to the steel or ferrite by the chemical.

Probably not the route to go, if one is in a hurry.

Meredith Lamb









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From: Pinpoint 
Subject: Re: MEK to remove glue
Date: Mon, 27 Jul 1998 21:13:32 -0700


>Bob Lamb recently suggested using MEK solvent to assist in
>dissolving glue holding magnets and metal washers from speakers;
>and of course for other parts desired.  It will remove paint and
>ruin plastic of course.

Acetone works well also and has same problems.....
   I worked with 50-50 acetone water in a fine spray mist for 2 years
inside of a very closed environment. The results was major brain and liver
damage and to this day I receive disability because of it...Watch out for
solvents!


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From: Fred S 
Subject: Re: period/mass etc of STM
Date: Mon, 27 Jul 1998 23:56:19 -0700

I like this idea Hubert. There is a material called Nitinol wire might
work well for this. I think Edmund Sceintific and Mondo Electronics both
carry it. It has a very predictable contraction with application of
current. They also have spring type actuators Another good idea might be
some kind of insulation such as teflon tubing to reduce the effect of
air currents. I have never used the stuff but was thinking about
designing a simple shaker table for calibrating sensors.  Anyone else
have any experience with this material ?

Fred  
-- 
Gravity:  It's not just a good idea.  It's the LAW !

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From: Hubert Vroomen 
Subject: Re: centering and temp comp of STM seis/ bouyancy effect
Date: Wed, 29 Jul 1998 00:33:02 +0200

Hello Sean-Thomas and others,

regarding my idea of centering through spring movement:

you wrote
>and simplicity. I wouldn't worry about the asthetics of it any
>more than I worried about the ski rack on the back of my old
>'70 Corvette: one has to do what has to be done. And the motor

whoa, a corvette, cool (drool). Sorry, had to say this, I know it is of
topic. But still, that ski-rack bothers me :-).

I was wondering, as Barry Lotz told in another mail of his calculations of
the bouyancy-effect, if you could give some more precise numbers of this
"negative temperature spring effect". If I remember well, you did some
experiments with pill-jars to compensate for a bouyancy effect, wasn't it.
I do not remember whether it was a succes or not, just curious to see if
bouyancy might give a rather large or small error-contribution. I mean, it
would not only help in temperature correction, but in pressure correction
as well.

thanks in advance for a interesting discussion,

Hubert

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From: Hubert Vroomen 
Subject: Re: period/mass etc of STM/ Nitinol actuators
Date: Wed, 29 Jul 1998 00:23:05 +0200

dear Fred and others,

the use of Nitinol and other so-called SMA (for shape-memory-alloys) is not
new. It has been done for about twenty years (if my memory serves me well)
and is also known under the name of artificial muscles. In fact, you can
find some coincidence with the behaviour of real muscles.

Regarding your idea of building a shaker table with SMA-actuators, it
definitely depends on the frequency range you are planning to use. SMA is
not good at higher frequencies (don't ask for a number, my intuition says
definitely bad above 1 Hz. or so), especially because of the thermal
problems concidering rapid heating and cooling. It is just pretty difficult
to heat a wire over a temperature range of several degrees with a frequency
of more then a several tenth's of a Herz, and it is even more difficult to
cool it at a frequency like that. 

In my, humble, opinion, I would go for a simple crank with a fixed
amplitude if building a shaker table. Just by variing the rotational speed
of the crank you change the frequency of vabration, and making a crank turn
very slow is not so difficult (stepping motor, DC motor with proper
gearing). To determing the speed at higher frequency you can use a
stroboscope or an electronic speed counter. For lower speeds, just mount a
piece of cardboard on the crank that "flaps" agains some fixed structure
and count the number of flaps during a certain time.

Someone on thit list has build a shaker table for a school project using an
electrical hand-drill, if I remember well. I think that it was Bob Hammond
in Alaska, but I am not sure (have difficulties with all those Bob's and
Hammonds on the list, to much german beer I suppose :-)).

Please don't hessitate to ask if you have any more questions.

Hubert

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From: S-T Morrissey 
Subject: mass buoyancy
Date: Tue, 28 Jul 1998 18:46:58 -0500 (CDT)

Barry,

I saw but cannot find your previous calculations for the buoyancy change
of the mass due to air density change due to air temperature change.

In general, we do not see this effect with the commercial VBB
seismometers; their temperature behavior is the same whether they
are evacuated or not. This seems to also be true for the "sealed"
sensors such as the STS-2 and the Guralp series, where any change
in temperature would actually change the density and consequently
the pressure of the air contained in the enclosure.

So I looked into the physics involved. Since density r falls out of the
ideal gas law PV = NkT, (P = pressure, V = volume, N = moles, k = constant,)
and r = N/V = P/kT, where T is the temperature in degrees Kelvin.
A 1 degree C change is actually a change from 298 to 299 deg. K (at 20
deg. C), or a change of about 0,336% in the density. Since the density of
air (at 20 deg C> )is 1.2047 MILLIgrams / cm^3. a change of 0.336% 
is 0.00404 milligrams.
When this is multiplied by the volume of the mass of the STM seis 
(about 50 cm^3), the buoyancy force is 0.202 milligrams. This is about
one-thousandth of the change in mass that is needed to correct the
leaf spring expansion for a 1 degree C temperature change.

Over a larger range of 10 to 20 deg. C (which my prototypes will
not operate over), the densities of air at STP can be found in the 
CRC handbook and are 1.2472 and 1.2047 mg/cm^3 at each temperature.
The difference is 0.0425 mg/cm^3, or a buoyancy of the mass of 2.125
milligrams. Again, this is a very small number compared to the mass
adjustment needed.

While we are discussing buoyancy problems, the CRC tables show an air
density change from 760 to 770 mm (hg) of 0.0159 milligrams/cm^3, or a
buoyancy force of about 0.0604 milligrams/millibar pressure change on
a mass of 50 cm^3 (which is why we should use lead on vertical sensors). 
This is the major noise source we have to deal with from the vertical 
sensor, assuming that good thermal insulation will keep the period 
of the thermal noise well out of our data passband.

Regards,
Sean-Thomas

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From: "Charles R. Patton" 
Subject: Re: period/mass etc of STM/ Nitinol actuators
Date: Tue, 28 Jul 1998 17:00:10 -0700

Nitinol, aka "muscle wire"; shape memory alloys; Dynalloy; Flexinol,
Titinol;  has some very nice characteristics including work-density
(being capable of large amounts of work vs volume but unfortunately it
would probably be unsuitable for this application.  The main drawback is
that it is not linear.  There is almost no change until it hits its
phase transition temperature, whereupon it goes through a large change
in strain strength (getting larger with increase of temperature)
together with significant hysteresis.  Typical numbers for Flexinol are
3% change in length from about 68 to 75 degrees Centigrade and then
returning through that 3% from 50 to 41 degrees Centigrade. Over the
whole 25 to 80 degree range it went through about a 5% change.  Note the
comment about strain strength =96 in order to use it to its best ability
it has to work against a preload such as a spring.  So in order to use
this you would have to preheat the wire to the transition range and hold
it there while controlling it.  That along with significant hysteresis
would make the control tough.

I still think that maybe the earlier post I made about controlling the
temperature of the spring itself might be the easiest, anyway just a
note to the discussion.

Charles R. Patton
Please change email to:  charles.r.patton@........

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From: Hubert Vroomen 
Subject: Re: mass buoyancy
Date: Wed, 29 Jul 1998 02:48:50 +0200

Hello Sean-Thomas and others,

I just did not completely understand the following part:

>In general, we do not see this effect with the commercial VBB
>seismometers; their temperature behavior is the same whether they
>are evacuated or not. This seems to also be true for the "sealed"
>sensors such as the STS-2 and the Guralp series, where any change
>in temperature would actually change the density and consequently
>the pressure of the air contained in the enclosure.

In my opinion, in a sealed container the mass of the enclosed air will not
change. So, a temperature change will result in a pressure change, but not
(in my opinion) in a change of density. The only reason I can imagine some
effect like this (in a sealed container) would be if you account for the
flexure or thermal contraction/elongation of the container, thereby
changing its inner volume. But because the thermal coefficients of air and
metals a different by several orders of magnitude this last term should not
be very important. In my feeling, only a changing density of the air inside
will result in a changing bouyancy, so this might be a reason for the fact
you do not see this effect in sealed seismometers.

But, to be honest, I have not done any calculations on this, so I might as
well be on the wrong side of the track.

>While we are discussing buoyancy problems, the CRC tables show an air
>density change from 760 to 770 mm (hg) of 0.0159 milligrams/cm^3, or a
>buoyancy force of about 0.0604 milligrams/millibar pressure change on
>a mass of 50 cm^3 (which is why we should use lead on vertical sensors). 
>This is the major noise source we have to deal with from the vertical 
>sensor, assuming that good thermal insulation will keep the period 
>of the thermal noise well out of our data passband.

this was the reason of your pill-jar experiment, wasn't it. Just a
question, can you separate between pressure and temperature effects? Here
in Europe (should be the same in the US) high pressure is often connected
to high temperature (and less rain, which makes correcting gravity
measurements a very interesting hobby :-)). I mean, do you see some diurnal
effect because of temperature, independent of the pressure-signal.

regards,

Hubert

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From: Hubert Vroomen 
Subject: Re: period/mass etc of STM/ Nitinol actuators
Date: Wed, 29 Jul 1998 02:34:57 +0200

Hello Charles and others,

my post on this subject was meant to be as a bit of information on Nitinol.
I totally agree with your analysis of its behaviour, that was one of the
reasons I discouraged it for the use in a shake-table. I think however,
that a non-SMA material with linear temperature behaviour (like brass, or
aluminium or simple steel) could be a nice actuator for large forces over
small strokes. And the fact that it is easily controlled via electric
current makes it even more interesting.

I just have some bad feelings with the usage of a heated part in a
seismometer, as we all are trying to keep these instruments on a as stable
temperature as possible. This would be indeed a pro for temperature
controlling of the spring. But, if you start controllng the
spring-temperature, it is not far away from controlling the temperature of
the whole instrument's enclosure, which has the added benefit of reducing
differential temperature effect because of different materials used in the
construction.

My idea of using the spring as an temperature-actuator is nearly the same
as your idea of controlling its temperature, but with the added benefit
that not only temperature might be controlled, but also (perhaps)
air-density/bouyancy effects.

It stays interesting this way, and somehow, a better world will result from
this :-)

Hubert


PS. Pardon my irony, just am finishing my PhD.-thesis and not much else
besides this list is giving me reason to smile these days, so pardon again.


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From: S-T Morrissey 
Subject: Re: centering and temp comp of STM seis/ bouyancy effect
Date: Tue, 28 Jul 1998 19:57:53 -0500 (CDT)

Hubert,
The old corvette has been parked in what has become the "seismometer
shop" since 1978 when the 4-piston brake calipers all started to
leak (bad castings) and I didn't have $1k per to replace them, and
I was spenting all my summers in Alaska. So how does one "antique" 
a corvette: park it in a garage and bury it with interesting "stuff";
we can still get in the drivers' door to play Gordon Lightfoot on 
the 8-track.

Re the seis barometric compensation with sealed pill jars installed
on the back side of the hinges: again, an experiment with an 
indefinite result. It seemed to help, but not notably; I suspect 
that they were actually flexing (plastic caps) with small changes 
of pressure. And figuring the correct volume*moment wrt. the boom
and the seis mass was an ambiguous endeavor.  I have thought of 
trying a copper toilet tank float if a real lightweight could be 
found. Or even some very low density but impervious solid.

In the mean time, the terraraium awaits being fitted out as a
pressure containment; not to be evacuated, but just to lengthen
the pressure time constant to several hours. I am working on a
way to pass the support of the seis through the glass bottom to
the pier in such a way that pressure flexing of the bottom does
not move the seis vertically. The other problem is a tight seal:
a small pinhole leak will breathe and blow the mass around.

The other idea is to shrink the design by at least 1/2 so it will
fit inside a large old fashioned pressure canner (Sears sells them).
They are cast aluminum and will hold a vacuum.

Regarding the leaf spring behavior of getting stiffer and extending
as the temperature decreases: I have no numbers on it, since the
effect in the seis depends on the mechanical period. I do observe
that the 4-second unit needs about a 1 cm shift (near the center of 
the boom) of the 10-gram trim mass to overcome a 1 deg. C temperature
change. The motor driven weight of 20 grams needs about 10 turns
(at 32tpi) to compensate for about half the temperature range, 
which causes a 7-volt offset of the mass position output, or 
about 200 microns with the feedback turned off. I need to modify
the 4-second (BETA) unit with the period adjustment feature of the
Gamma units to study this effect at longer periods. It may make
matters worse. Longer mechanical periods of a VBB fedback system
allow a better defined response, but are not necessary unless one
wants an extremely long period response. I have found that the VBB
period can be more than 20 times the mechanical period.

regards,
Sean-Thomas

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From: S-T Morrissey 
Subject: aquarium heater?
Date: Tue, 28 Jul 1998 20:08:01 -0500 (CDT)

Hubert,
I forgot to mention the plan C for temperature: to put an
aquarium heater in a large (liter+) jar of water inside the
seis case. They control within a degree F, and the jar of
water would average out the cycling of the heater. Maaybe
the heater can be broken into to refine its sensitivity.

I should do this on the prototype, because the 1000 second high
pass to the old drum recorder allows some DC drift through, so
the traces crowd or spread apart as the mass wanders around
over periods of hours or more.
 
Regards,
Sean-thomas

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From: S-T Morrissey 
Subject: Re: mass buoyancy
Date: Tue, 28 Jul 1998 20:35:27 -0500 (CDT)

Hubert,

I said it wrong about the sealed containers; you are right.
The density (mass per volume) cannot change because the mass
of air is held constant, except for the (probable) flexing
you noted. The pressure will change with temperature per 
the gas law.

Regarding diurnal pressure/temperature/tides/etc. I have
done some short manual logging of the mass position of the
VBB seismometer when the atmospherics were quiet (high 
pressure), and it seems to be earth tidal. But until I get 
the pressure and temperature under control, logging such 
would be useless. Then I will connect up the miniature strip 
chart recorders we use for tiltmeter data.

Speaking of which, you might be interested that I have been
operating a very old Geodynamics Recording Gravimeter here since I
arrived in '69. It is a quartz suspension, with capacitive
displacement output, using double active thermal jackets and
passive pressure control (a sealed acryllic case). Not the 
current superconducting art, but a good teaching/interest aid.
I have closely followed these instruments; we have a NIST? site
in our basement that they periodically occupy with the lasar+
corner-cube + "superspring" instrument.

Regards,
Sean-Thomas


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From: Fred Gibson 
Subject: Re: MEK to remove glue
Date: Wed, 29 Jul 1998 01:11:54 -0400

Hello all,

Being a former adhesive chemist, thought a few tricks might be helpful.  It
would be less effective, but isopropyl alcohol, IPA, will slowly soften
many adhesives.  IPA will be less likely to destroy a plastic part, but can
fog some clear panels.  Best to try a small spot to see.  From a safety
point of view, gloves and ventilation is the key with anything other than
water.  I havn't looked at the recent bottles of fingernail polish remover
(they once used Acetone) but it may work as well since nail polish is a
coating.


Fred

09:13 PM 7/27/98 -0700, you wrote:
>
>>Bob Lamb recently suggested using MEK solvent to assist in
>>dissolving glue holding magnets and metal washers from speakers;
>>and of course for other parts desired.  It will remove paint and
>>ruin plastic of course.
>
>Acetone works well also and has same problems.....
>   I worked with 50-50 acetone water in a fine spray mist for 2 years
>inside of a very closed environment. The results was major brain and liver
>damage and to this day I receive disability because of it...Watch out for
>solvents!
>
>
>_____________________________________________________________________
>
>Public Seismic Network Mailing List (PSN-L)
>
>To leave this list email listserver@............. with the body of the 
>message: leave PSN-L
>


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From: Steve Hammond 
Subject: Re: Include PSN in seismic network survey?
Date: Tue, 28 Jul 1998 21:13:01 -0700

Here is the station list for the Assesmrnt and IASPEI Handbook that
Steve Malone, the CNSS Chair is requesting. Please review your station
information as "I" (as in there is danger here...) defined your station
SEED-LIKE type based on the inputs you gave to Dave some time back. If
you don't agree please cut-out the line and send the old line and new
inputs to me in a note at:
 
Shammon1@.............  

Alos, if you don't want to be included you must tell me now. What you
see is what you get--  

You have until Wed. JULY 29 to make your comments because the deadline
for submission is July 31. 
 
_____________________________  Legend
_________________________________________________
Field 1
	Station Operator
Field 2
	Latitude	Longitude
Field 3
	XXX  see legend  (1st,2nd,3rd charachter

1st charachter

	J = Short period <10 seconds
	O = Long-period >10 seconds
	E = Accelerometer

2nd charachter
	S = Short period corner <10 seconds
	B = Broad Band 10 to 89 seconds corner > 10 seconds
	H = smoke / chart recorder >80 seconds

3rd charachter

	Number of orientations (ie 1-single channel, 2..,  3... )

Field 4 Network Name (PSN NetWork)

_____________________________ LIST starts
_____________________________________________

"Name:            Grayling School, Alaska "							GRY	62.8	-160.1	JS1
PSN
"Name:            HSC;  Fairbanks, Alaska"							HSC	62.8	-160.1	JS1	PSN
"Name:            McGrath School, Alaska"							MCG	62.9	-155.6	JS1	PSN
"Name:            Pearl Creek School, Alaska"							PCK	64.9	-147.8	JS1
PSN
"Name:            SRA,  Fairbanks, Alaska"							SRA	62.8	-160.1	JS1	PSN
"Name:           Al Allworth    
W7PXX                                                   (51)							AA1
42.51	-124.33	JS1	PSN
"Name:           Albert Judge 
(Alby)                                                    (37)							AJ1
-32	115	OB1	PSN
"Name:           Almaden Country School, Middle School Science Class  
(48)"							ACS	37.12	-121.5	OB1	PSN
NAME:           Arie 
Verveer                                                          
(59)							AV1	-32.0083	116.1346	OB2	PSN
NAME:           Barry
Lotz                                                             
(15)							BL1	39.23	-121.07	OB1	PSN
NAME:           Bill
Scolnik                                                           
(28)							BS1	41.05	-74.25	JS1	PSN
NAME:           Bill
Scolnik                                                            (28)
		BS2	33.5	-74.25	OB2	PSN
NAME:           Bob
Hammond                                                            
(13)							BH1	64.921	-147.937	JH1	PSN
NAME:           Bob
Hammond                                                            
(13)							BH2	64.921	-147.937	OH1	PSN
NAME:           Bob Lewis   
WB5FDF                                                   (39)							FD1
33.1	-96.43	OB1	PSN
NAME:           Bob Lewis   
WB5FDF                                                   (39)							FD2
33.1	-96.43	JS1	PSN
NAME:           Bob
Teller                                                             
(9)							BT1	46.19	-111.3	OB3	PSN
NAME:           Brian
Zimmerman                                                        
(16)							BZ1	41.875	-80.125	JS1	PSN
NAME:           Brian
Zimmerman                                                        
(16)							BZ2	41.875	-80.125	OB2	PSN
NAME:           Bruce Kinney
			BK1	37.24	-121.839	OB1	PSN
NAME:           Charlie
Rond                                                           
(35)							CR1	35.041	-89.84	OB1	PSN
NAME:           Charlie
Thompson                                                       
(10)							BUE	30.112	-97.891	OB2	PSN
Name:           Clark
Wockner                                                          
(43)							CW1	40.78	-87.75	OB1	PSN
NAME:           Claudio
Conti                                                          
(58)							CC1	37.035	15.135	OB1	PSN
NAME:           Claudio
Conti                                                          
(58)							CC2	37.035	15.135	SJ3	PSN
NAME:           Darrell
Collins                                                        
(27)							DC1	33.5	-111.9	JS1	PSN
NAME:           Darrell
Collins                                                        
(27)							DC2	33.5	-111.9	OB2	PSN
NAME:           Dave Nelson    
ZL4TBN                                                  (4)							DN1
-45.8	170.3	JS1	PSN
NAME:           Dave Nelson    
ZL4TBN                                                  (4)							DN2
-45.8	170.3	JS1	PSN
NAME:           Dave Nelson    
ZL4TBN                                                  (4)							DN3
-45.8	170.3	JS1	PSN
NAME:           Dave Nelson    
ZL4TBN                                                  (4)							DN4
-45.8	170.3	OB1	PSN
NAME:           David
Wolny                                                            
(34)							DW1	39.091	-108.487	OB1	PSN
NAME:           Dennis
Leatart                                                         
(8)							DL1	34.1	-118.88	JS1	PSN
NAME:           Dick
Webb                                                              
(30)							RW1	35.54	-78.39	OB1	PSN
Name:           Donald Sieber
(retired)                                                 (47)							DS1
43.61	-116.21	JS1	PSN
NAME:           Douglas
McConnell                                                      
(49)							DM1	-30.317	149.988	OH1	PSN
NAME:           Francesco
Nucera                                                        (53)						
FN1	43.48	13.48	ES1	PSN
NAME:           Francesco
Nucera                                                        (53)						
FN2	39.96	-82.98	OB1	PSN
NAME:           Frank Cooper   
W5VID                                                   (20)							FC1
29.52	-95.17	OB1	PSN
NAME:           Fred
Bruenjes                                                          
(2)							FB1	32.822	-117.084	OB1	PSN
NAME:           Fred
Bruenjes                                                          
(2)							FB2	32.822	-117.084	OB1	PSN
NAME:           George
Bush                                                            
(14)							TSR	38.74	-123.5	ES3	PSN
NAME:           Giovanni
Rotta                                                         
(45)							GR1	46.22	13.18	OB1	PSN
NAME:           Gregory A.
Lyzenga                                                      (7)						
GL1	34.20N	-118.13	OB1	PSN
NAME:           Jack
Sandgathe                                                         
(23)							JS1	49.35	-119.62	OB1	PSN
NAME:           Jan Froom	
			GC1	37.5	-121.1	OB2	PSN
NAME:           Jan Froom	
			GC2	37.5	-121.1	JS1	PSN
NAME:           Jean-Jacques
Hunsinger                                                (41)							JCH
47.5	7	OB1	PSN
"NAME:           Jeff Batten  ( Caltech Seismo Lab. Pasadena, Ca.)    
(25)"							JB1	34.13	-118.12	JS2	PSN
"NAME:           Jeff Batten  ( Caltech Seismo Lab. Pasadena, Ca.)    
(25)"							JB2	34.13	-118.12	OB1	PSN
"NAME:           Jeff Batten  ( Caltech Seismo Lab. Pasadena, Ca.)    
(25)"							JB3	34.13	-118.12	JH1	PSN
NAME:           Jim
Lovell                                                             
(22)							JL1	-43.52	172.61	OS1	PSN
NAME:           Karl
Cunningham                                                        
(40)							KC1	32.7705	-116.978	JS1	PSN
NAME:           Karl
Cunningham                                                        
(40)							KC2	32.7705	-116.978	ES1	PSN
NAME:           Kees
Verbeek                                                           
(12)							KV1	51.26	5.3	JH1	PSN
NAME:           Ken
Navarre                                                            
(21)							KN1	37.39	-121.99	OB1	PSN
NAME:           Larry
Cochrane                                                         
(1)							LC1	37.496	-122.241	OB1	PSN
NAME:           Larry
Cochrane                                                         
(1)							LC2	37.496	-122.241	JS3	PSN
NAME:           Larry
Cochrane                                                         
(1)							LC3	37.496	-122.241	OB1	PSN
NAME:           Liberio
Rossi                                                          
(56)							LR1	43.54	10.34	JS3	PSN
NAME:           Lucas
Haag                                                             
(11)							LH1	40.13N	-100.29	JS1	PSN
NAME:           Malcolm
Sinclair                                                       
(32)							DHQ	-45.6	170.4	JH1	PSN
NAME:           Malcolm
Sinclair                                                       
(32)							MS1	-43.55	172.68	JH1	PSN
NAME:           Mark
Halliday                                                          
(5)							MH1	37.085	-122.106	JS1	PSN
NAME:           Mark
Halliday                                                          
(5)							MH2	37.085	-122.106	OB1	PSN
Name:           Martin S.
Brewer                                                        (44)						
MB1	32.278	-64.793	OB2	PSN
NAME:           Meredith
Lamb                                                          
(52)							ML1	39.703	-105.006	OB3	PSN
NAME:           Paolo
Frediani                                                         
(57)							PF1	44.13	10.06	SJ2	PSN
NAME:           Paolo
Frediani                                                         
(57)							PF2	44.13	10.06	OB1	PSN
"NAME:           Peter Styles, Sam
Toon                                                (36)"							ST1	53.4
-2.96	JS1	PSN
NAME:           Phil
Giannini                                                          
(17)							SFX	37.72	-122.416	OB2	PSN
NAME:           Phil
Giannini                                                          
(17)							SFZ	37.72	-122.416	JS1	PSN
NAME:           Phil
Giannini                                                          
(17)							SMX	37.75	-122.2	JN3	PSN
NAME:           Phil
Giannini                                                          
(17)							SMZ	37.75	-122.2	JN3	PSN
NAME:           Phil
Giannini                                                          
(17)							TVN	37.75	-122.2	OB1	PSN
NAME:           Phil
Giannini                                                          
(17)							TVZ	37.75	-122.2	JS1	PSN
NAME:           Richard Chelberg
			RC1	37.24	-121.845	OB1	PSN
NAME:           Robert (Bob) L.
Barns                                                   (3)							RB1
40.6802N	-74.4142	OB1	PSN
NAME:           Robert L.
Laney                                                         (50)						
RL1	38.902	-77.38	OB2	PSN
NAME:           Roberto E.
Pozzo                                                        (38)						
RP1	44.46	8.21	OB1	PSN
NAME:           Roberto E.
Pozzo                                                        (38)						
RP2	44.46	8.21	JS1	PSN
NAME:           Roger
Griggs                                                           
(6)							RG1	37.98	-121.72	OB1	PSN
NAME:           Roger
Sorensen                                                         
(19)							RS1	34.16	-118.36	ES2	PSN
NAME:           Roger
Sorensen                                                         
(19)							RS2	34.16	-118.36	JS3	PSN
Name:           Ron
Westfall                                                           
(42)							RW1	49.325	-122.996	OB2	PSN
NAME:           Southland Boys High
School                                         (60)							SHS	-46.5
168.2	SJ1	PSN
NAME:           Stephen
Mortensen                                                      
(55)							SM1	38.828	-120.978	OB1	PSN
NAME:           Steve
Clark                                                            
(24)							SC1	44.99	-122.96	JS1	PSN
NAME:           Steve
Hammond                                                          
(18)							FSX	37.245	-121.815	OB2	PSN
NAME:           Steve
Hammond                                                          
(18)							FSZ	37.245	-121.815	JS3	PSN
NAME:           Tom
Frey                                                               
(26)							LK1	47.17	-122.49	OB1	PSN
NAME:           Tony
Potenzo                                                           
(46)							TP1	19.723	-155.991	OB1	PSN
NAME:           Tony
Potenzo                                                           
(46)							TP2	19.723	-155.991	JS1	PSN
NAME:           Walt
Catino                                                            
(29)							WC1	45.42	-123.04	SL2	PSN

_____________________________________________________________________

Public Seismic Network Mailing List (PSN-L)


From: "Al Allworth" 
Subject: RE: MEK to remove glue
Date: Tue, 28 Jul 1998 23:11:56 -0700

Hi All,

The last speaker I tried to take apart was assembled with epoxy. It was so
strong that the
magnet broke. A thin layer of magnet material stayed on the frame. I don't
know if there is anything that will soften epoxy. I know alcohol or acetone
has no effect.

> -----Original Message-----
> From: Fred Gibson [mailto:fgibson@.......
> Sent: Tuesday, July 28, 1998 10:12 PM
> To: PSN-L Mailing List
> Subject: Re: MEK to remove glue
>
>
> Hello all,
>
> Being a former adhesive chemist, thought a few tricks might be
> helpful.  It
> would be less effective, but isopropyl alcohol, IPA, will slowly soften
> many adhesives.  IPA will be less likely to destroy a plastic
> part, but can
> fog some clear panels.  Best to try a small spot to see.  From a safety
> point of view, gloves and ventilation is the key with anything other than
> water.  I havn't looked at the recent bottles of fingernail polish remover
> (they once used Acetone) but it may work as well since nail polish is a
> coating.
>
>
> Fred
>
> 09:13 PM 7/27/98 -0700, you wrote:
> >
> >>Bob Lamb recently suggested using MEK solvent to assist in
> >>dissolving glue holding magnets and metal washers from speakers;
> >>and of course for other parts desired.  It will remove paint and
> >>ruin plastic of course.
> >
> >Acetone works well also and has same problems.....
> >   I worked with 50-50 acetone water in a fine spray mist for 2 years
> >inside of a very closed environment. The results was major brain
> and liver
> >damage and to this day I receive disability because of it...Watch out for
> >solvents!
> >
> >
> >_____________________________________________________________________
> >
> >Public Seismic Network Mailing List (PSN-L)
> >
> >To leave this list email listserver@............. with the body of the
> >message: leave PSN-L
> >
>
>
> _____________________________________________________________________
>
> Public Seismic Network Mailing List (PSN-L)
>
> To leave this list email listserver@............. with the body of the
> message: leave PSN-L
>


_____________________________________________________________________

Public Seismic Network Mailing List (PSN-L)


From: Hubert Vroomen 
Subject: several points regarding thermal, pressure and bouyancy
Date: Wed, 29 Jul 1998 12:45:36 +0200

Hello Sean-Thomas and others,

Thanks for your answers regarding bouyancy effects and temperature
compensation.

BTW, what do you mean by antiqueing your corvette? At this side of the
ocean, a corvette is considered a classic (as probably a BMW or Porsche at
your side), so you do not have to make it an antique to have a special car
:-).

>Re the seis barometric compensation with sealed pill jars installed
>on the back side of the hinges: again, an experiment with an 
>indefinite result. It seemed to help, but not notably; I suspect 
>that they were actually flexing (plastic caps) with small changes 
>of pressure. And figuring the correct volume*moment wrt. the boom
>and the seis mass was an ambiguous endeavor.  I have thought of 
>trying a copper toilet tank float if a real lightweight could be 
>found. Or even some very low density but impervious solid.

I am thinking about a material that would fullfil these requirements, but
have not found anything. he closest I have come is using a glass jar with a
small glass plate waxed over the opening (should be stiffer than a plastic
cap). But to be honest, I doubt if the flexing of the caps would be so
notable, we are talking small pressure differences here, and the plasic
caps I know are pretty stiff, but one should rather try to calculate this
effect than theorise (mea culpa)! To tune the volume you could use a glass
tube of the correct lenght and seal both end with waxed glass plates. 

Determination of the volume of a irregular object is easy (as long as you
do not mind drying it afterwards). Just take a basket of water filled to
the rim, place it on a scale and write down the weight, place the object to
be measured in the basket (it should sink!) and take care that the spilling
water does not enter the scale. Remove the object and measure the weight
again, the difference with the first number is the mass of the water that
was spilled because of the volume of the object. Divide this mass by the
specific mass of the water at the measuring temperature, and you have the
volume of the object.

Measuring the volume-moment around a certain axis is much more difficult,
you could do volume measurements of parts of the same material, and
multiply these volumes with the lever arms of the center of gravity (which
is also the center of volume of homogeneous materials/objects) around the
axis. Much more work but doable, rather inconvenient if you have already
assembled the seismometer.

>In the mean time, the terraraium awaits being fitted out as a
>pressure containment; not to be evacuated, but just to lengthen
>the pressure time constant to several hours. I am working on a
>way to pass the support of the seis through the glass bottom to
>the pier in such a way that pressure flexing of the bottom does
>not move the seis vertically. The other problem is a tight seal:
>a small pinhole leak will breathe and blow the mass around.

Have you thought about using the terrarium upside-down, putting a generous
bead of silicone on your pier around the seismometer, pressing the cables
in this bead (with more silicone to follow) and pressing the terrarium
upside-down in this bead. If the tiles of your pier are close enough, this
concept might work and could give you a simple solution. This way, the
seismometer could still stand on the original pier with unmodified support.

>The other idea is to shrink the design by at least 1/2 so it will
>fit inside a large old fashioned pressure canner (Sears sells them).
>They are cast aluminum and will hold a vacuum.

I have some ideas in which the base of the seismometer is also the pressure
containment (I am very into exostructures). But it would need a rather
large chunk of stainless steel (expensive) or aluminium (cheaper but not
ideal because of the different thermal expansion compared to the
leaf-spring) and could still be to weak to stand larger pressure changes.
If my time permits (end of october or so) I will try to make a drawing of
it, at this moment it only exists in my head.

>I forgot to mention the plan C for temperature: to put an
>aquarium heater in a large (liter+) jar of water inside the
>seis case. They control within a degree F, and the jar of
>water would average out the cycling of the heater. Maaybe
>the heater can be broken into to refine its sensitivity.

good idea, water is a good thermal buffer. The only disadvantage I see is
the possible corrosion danger and the problem of local condensation, which
would lead to changes of the weight of the mass/beam structure (funny jumps
in the output would be the result). Both problems can be countered by
sealing the heated jar vapourtight.

>Speaking of which, you might be interested that I have been
>operating a very old Geodynamics Recording Gravimeter here since I
>arrived in '69. It is a quartz suspension, with capacitive
>displacement output, using double active thermal jackets and
>passive pressure control (a sealed acryllic case). Not the 
>current superconducting art, but a good teaching/interest aid.

Is this a follow-up of the old Worden gravimeter (it was optical if I
remember well)? I know that in Australia or New Zealand a new quartz
suspension gravimeter has been build by Hugill (beginning of the 80-ties)
that also uses capacitive displacement sensoring. It is marketed by a
Canadian company I believe.

>I have closely followed these instruments; we have a NIST? site
>in our basement that they periodically occupy with the lasar+
>corner-cube + "superspring" instrument.

really? Well, that probably means no hip-hop parties then, isn't it? I have
read some papers by those guys and it is a really marvelous instrument.
With proper electronics, the "superspring" concept could also be a
candidate for a vertical seismometer (like every vertically swinging object
with sufficiently large period).

BTW, Walt Williams asked in a seperate post about calibration of
gravimeters. This NIST instrument is one of the absolute gravimeters
(free-fall instrument) that is used to map gravity calibration ranges
around the world.


regards,

Hubert


PS Sean-Thomas, as you have some years of experience in this field. Do you
have any information about the bodenseewerke GSS20 respectively askania
GSS2/KSS2 ship-born gravity sensor. I am in desperate need for
documentation on this instrument and the original manufacturer
(Bodenseewerke in Meersburg, Germany) could not help me anymore.

_____________________________________________________________________

Public Seismic Network Mailing List (PSN-L)


From: Edward Cranswick 
Subject: Re: Include PSN in seismic network survey?
Date: Wed, 29 Jul 1998 11:59:53 -0600

Steve-
    I think your list is great!  You could just go ahead and send a copy to Steve Malone directly when you think it is ready (t
onight
being the deadline for changes as you suggested), and CC a copy to the PSN-L and me.  Include the note he sent to me and that I

forwarded to you and PSN-L so he knows where it is coming from.  Thank you very much for putting this together.
    Regards to the family.
-Edward

Steve Hammond wrote:

> Hi Steve,
> I have the station list together for the Public Seismic Network and it
> is out for review on the PSN mail list. The group has until Wed. to
> reply. At that point I will cut off the Station operator field and send
> you the station list as requested. Items 1 - 13 for the handbook will
> follow ASAP. Here is a Sample. We currently have 94 stations in the
> list.
> Regards, Steve Hammond PSN San Jose
>
> ----------- legend -------------
> Field 1
>         Station Operator
> Field 2
>         Latitude        Longitude
> Field 3
>         XXX  see legend  (1st,2nd,3rd charachter
>
> 1st charachter
>
>         J = Short period <10 seconds
>         O = Long-period >10 seconds
>         E = Accelerometer
>
> 2nd charachter
>         S = Short period corner <10 seconds
>         B = Broad Band 10 to 89 seconds
>         H = smoke / chart recorder >80 seconds
>
> 3rd charachter
>
>         Number of orientations (ie 1-single channel)
>
> Field 4 Network Name
>
> ------------------ Sample data ----------------------------------
>
> "Name:            Grayling School, Alaska "                                                     GRY     62.8    -160.1  JS1
> PSN
> "Name:            HSC;  Fairbanks, Alaska"                                                      HSC     62.8    -160.1  JS1  
   PSN
> "Name:            McGrath School, Alaska"                                                       MCG     62.9    -155.6  JS1  
   PSN
> "Name:            Pearl Creek School, Alaska"                                                   PCK     64.9    -147.8  JS1
> PSN
> "Name:            SRA,  Fairbanks, Alaska"                                                      SRA     62.8    -160.1  JS1  
   PSN
> "Name:           Al Allworth
> W7PXX                                                   (51)                                                    AA1
> 42.51   -124.33 JS1     PSN
> "Name:           Albert Judge
> (Alby)                                                    (37)                                                  AJ1
> -32     115     OB1     PSN
> "Name:           Almaden Country School, Middle School Science Class
> (48)"
> ----------------------------  snip snip  -------------------------------
> > *********************************************************************
> > [Steve Malone wrote:]
> >
> >         Also, on a different subject, since I know you are interested and
> > involved in the Peoples Seismograph Network I have a question.  I have
> > been tasked with doing an inventory of seismic networks in the US and am
> > getting a response from most of the regional networks (ie members of the
> > CNSS).  The `PSN' has never been an actual part of the CNSS since it is a
> > pretty ad hoc group with no central authority (as it should).  However,
> > for this inventory (and maybe just to increase its visability it might be



--
Edward Cranswick                Tel: 303-273-8609
US Geological Survey, MS 966    Fax: 303-273-8600
PO Box 25046, Federal Center    cranswick@........
Denver, CO 80225-0046  USA      E.M. Forster said, "Only connect".




_____________________________________________________________________

Public Seismic Network Mailing List (PSN-L)


From: "Giovanni Rotta" 
Subject: R: Include PSN in seismic network survey?
Date: Wed, 29 Jul 1998 19:47:10 +0200

Hi Steve !
Please, tell me how many time we have to send you the requested data.
Have my best regards,
Giovanni

Giovanni Rotta
rottag@..........
Via F. Pizzigoni, 10
33010 Resia (Udine) Italy
Lat. 46.373N   Long. 13.305E
QTH Locator JN66PI

----------
> Da: Steve Hammond 
> A: PSN-L Mailing List 
> Cc: steve@......................
> Oggetto: Re: Include PSN in seismic network survey?
> Data: mercoledì 29 luglio 1998 6.13
> 
> Here is the station list for the Assesmrnt and IASPEI Handbook that
> Steve Malone, the CNSS Chair is requesting. Please review your station
> information as "I" (as in there is danger here...) defined your station
> SEED-LIKE type based on the inputs you gave to Dave some time back. If
> you don't agree please cut-out the line and send the old line and new
> inputs to me in a note at:
>  
> Shammon1@.............  
> 
> Alos, if you don't want to be included you must tell me now. What you
> see is what you get--  
> 
> You have until Wed. JULY 29 to make your comments because the deadline
> for submission is July 31. 
>  
> _____________________________  Legend
> _________________________________________________
> Field 1
> 	Station Operator
> Field 2
> 	Latitude	Longitude
> Field 3
> 	XXX  see legend  (1st,2nd,3rd charachter
> 
> 1st charachter
> 
> 	J = Short period <10 seconds
> 	O = Long-period >10 seconds
> 	E = Accelerometer
> 
> 2nd charachter
> 	S = Short period corner <10 seconds
> 	B = Broad Band 10 to 89 seconds corner > 10 seconds
> 	H = smoke / chart recorder >80 seconds
> 
> 3rd charachter
> 
> 	Number of orientations (ie 1-single channel, 2..,  3... )
> 
> Field 4 Network Name (PSN NetWork)
> 
> _____________________________ LIST starts
> _____________________________________________
> 
> "Name:            Grayling School, Alaska "							GRY	62.8	-160.1	JS1
> PSN
> "Name:            HSC;  Fairbanks, Alaska"							HSC	62.8	-160.1	JS1	PSN
> "Name:            McGrath School, Alaska"							MCG	62.9	-155.6	JS1	PSN
> "Name:            Pearl Creek School, Alaska"							PCK	64.9	-147.8	JS1
> PSN
> "Name:            SRA,  Fairbanks, Alaska"							SRA	62.8	-160.1	JS1	PSN
> "Name:           Al Allworth    
> W7PXX                                                   (51)							AA1
> 42.51	-124.33	JS1	PSN
> "Name:           Albert Judge 
> (Alby)                                                    (37)							AJ1
> -32	115	OB1	PSN
> "Name:           Almaden Country School, Middle School Science Class  
> (48)"							ACS	37.12	-121.5	OB1	PSN
> NAME:           Arie 
> Verveer                                                          
> (59)							AV1	-32.0083	116.1346	OB2	PSN
> NAME:           Barry
> Lotz                                                             
> (15)							BL1	39.23	-121.07	OB1	PSN
> NAME:           Bill
> Scolnik                                                           
> (28)							BS1	41.05	-74.25	JS1	PSN
> NAME:           Bill
> Scolnik                                                            (28)
> 		BS2	33.5	-74.25	OB2	PSN
> NAME:           Bob
> Hammond                                                            
> (13)							BH1	64.921	-147.937	JH1	PSN
> NAME:           Bob
> Hammond                                                            
> (13)							BH2	64.921	-147.937	OH1	PSN
> NAME:           Bob Lewis   
> WB5FDF                                                   (39)							FD1
> 33.1	-96.43	OB1	PSN
> NAME:           Bob Lewis   
> WB5FDF                                                   (39)							FD2
> 33.1	-96.43	JS1	PSN
> NAME:           Bob
> Teller                                                             
> (9)							BT1	46.19	-111.3	OB3	PSN
> NAME:           Brian
> Zimmerman                                                        
> (16)							BZ1	41.875	-80.125	JS1	PSN
> NAME:           Brian
> Zimmerman                                                        
> (16)							BZ2	41.875	-80.125	OB2	PSN
> NAME:           Bruce Kinney
> 			BK1	37.24	-121.839	OB1	PSN
> NAME:           Charlie
> Rond                                                           
> (35)							CR1	35.041	-89.84	OB1	PSN
> NAME:           Charlie
> Thompson                                                       
> (10)							BUE	30.112	-97.891	OB2	PSN
> Name:           Clark
> Wockner                                                          
> (43)							CW1	40.78	-87.75	OB1	PSN
> NAME:           Claudio
> Conti                                                          
> (58)							CC1	37.035	15.135	OB1	PSN
> NAME:           Claudio
> Conti                                                          
> (58)							CC2	37.035	15.135	SJ3	PSN
> NAME:           Darrell
> Collins                                                        
> (27)							DC1	33.5	-111.9	JS1	PSN
> NAME:           Darrell
> Collins                                                        
> (27)							DC2	33.5	-111.9	OB2	PSN
> NAME:           Dave Nelson    
> ZL4TBN                                                  (4)							DN1
> -45.8	170.3	JS1	PSN
> NAME:           Dave Nelson    
> ZL4TBN                                                  (4)							DN2
> -45.8	170.3	JS1	PSN
> NAME:           Dave Nelson    
> ZL4TBN                                                  (4)							DN3
> -45.8	170.3	JS1	PSN
> NAME:           Dave Nelson    
> ZL4TBN                                                  (4)							DN4
> -45.8	170.3	OB1	PSN
> NAME:           David
> Wolny                                                            
> (34)							DW1	39.091	-108.487	OB1	PSN
> NAME:           Dennis
> Leatart                                                         
> (8)							DL1	34.1	-118.88	JS1	PSN
> NAME:           Dick
> Webb                                                              
> (30)							RW1	35.54	-78.39	OB1	PSN
> Name:           Donald Sieber
> (retired)                                                 (47)							DS1
> 43.61	-116.21	JS1	PSN
> NAME:           Douglas
> McConnell                                                      
> (49)							DM1	-30.317	149.988	OH1	PSN
> NAME:           Francesco
> Nucera                                                        (53)						
> FN1	43.48	13.48	ES1	PSN
> NAME:           Francesco
> Nucera                                                        (53)						
> FN2	39.96	-82.98	OB1	PSN
> NAME:           Frank Cooper   
> W5VID                                                   (20)							FC1
> 29.52	-95.17	OB1	PSN
> NAME:           Fred
> Bruenjes                                                          
> (2)							FB1	32.822	-117.084	OB1	PSN
> NAME:           Fred
> Bruenjes                                                          
> (2)							FB2	32.822	-117.084	OB1	PSN
> NAME:           George
> Bush                                                            
> (14)							TSR	38.74	-123.5	ES3	PSN
> NAME:           Giovanni
> Rotta                                                         
> (45)							GR1	46.22	13.18	OB1	PSN
> NAME:           Gregory A.
> Lyzenga                                                      (7)						
> GL1	34.20N	-118.13	OB1	PSN
> NAME:           Jack
> Sandgathe                                                         
> (23)							JS1	49.35	-119.62	OB1	PSN
> NAME:           Jan Froom	
> 			GC1	37.5	-121.1	OB2	PSN
> NAME:           Jan Froom	
> 			GC2	37.5	-121.1	JS1	PSN
> NAME:           Jean-Jacques
> Hunsinger                                                (41)							JCH
> 47.5	7	OB1	PSN
> "NAME:           Jeff Batten  ( Caltech Seismo Lab. Pasadena, Ca.)    
> (25)"							JB1	34.13	-118.12	JS2	PSN
> "NAME:           Jeff Batten  ( Caltech Seismo Lab. Pasadena, Ca.)    
> (25)"							JB2	34.13	-118.12	OB1	PSN
> "NAME:           Jeff Batten  ( Caltech Seismo Lab. Pasadena, Ca.)    
> (25)"							JB3	34.13	-118.12	JH1	PSN
> NAME:           Jim
> Lovell                                                             
> (22)							JL1	-43.52	172.61	OS1	PSN
> NAME:           Karl
> Cunningham                                                        
> (40)							KC1	32.7705	-116.978	JS1	PSN
> NAME:           Karl
> Cunningham                                                        
> (40)							KC2	32.7705	-116.978	ES1	PSN
> NAME:           Kees
> Verbeek                                                           
> (12)							KV1	51.26	5.3	JH1	PSN
> NAME:           Ken
> Navarre                                                            
> (21)							KN1	37.39	-121.99	OB1	PSN
> NAME:           Larry
> Cochrane                                                         
> (1)							LC1	37.496	-122.241	OB1	PSN
> NAME:           Larry
> Cochrane                                                         
> (1)							LC2	37.496	-122.241	JS3	PSN
> NAME:           Larry
> Cochrane                                                         
> (1)							LC3	37.496	-122.241	OB1	PSN
> NAME:           Liberio
> Rossi                                                          
> (56)							LR1	43.54	10.34	JS3	PSN
> NAME:           Lucas
> Haag                                                             
> (11)							LH1	40.13N	-100.29	JS1	PSN
> NAME:           Malcolm
> Sinclair                                                       
> (32)							DHQ	-45.6	170.4	JH1	PSN
> NAME:           Malcolm
> Sinclair                                                       
> (32)							MS1	-43.55	172.68	JH1	PSN
> NAME:           Mark
> Halliday                                                          
> (5)							MH1	37.085	-122.106	JS1	PSN
> NAME:           Mark
> Halliday                                                          
> (5)							MH2	37.085	-122.106	OB1	PSN
> Name:           Martin S.
> Brewer                                                        (44)						
> MB1	32.278	-64.793	OB2	PSN
> NAME:           Meredith
> Lamb                                                          
> (52)							ML1	39.703	-105.006	OB3	PSN
> NAME:           Paolo
> Frediani                                                         
> (57)							PF1	44.13	10.06	SJ2	PSN
> NAME:           Paolo
> Frediani                                                         
> (57)							PF2	44.13	10.06	OB1	PSN
> "NAME:           Peter Styles, Sam
> Toon                                                (36)"							ST1	53.4
> -2.96	JS1	PSN
> NAME:           Phil
> Giannini                                                          
> (17)							SFX	37.72	-122.416	OB2	PSN
> NAME:           Phil
> Giannini                                                          
> (17)							SFZ	37.72	-122.416	JS1	PSN
> NAME:           Phil
> Giannini                                                          
> (17)							SMX	37.75	-122.2	JN3	PSN
> NAME:           Phil
> Giannini                                                          
> (17)							SMZ	37.75	-122.2	JN3	PSN
> NAME:           Phil
> Giannini                                                          
> (17)							TVN	37.75	-122.2	OB1	PSN
> NAME:           Phil
> Giannini                                                          
> (17)							TVZ	37.75	-122.2	JS1	PSN
> NAME:           Richard Chelberg
> 			RC1	37.24	-121.845	OB1	PSN
> NAME:           Robert (Bob) L.
> Barns                                                   (3)							RB1
> 40.6802N	-74.4142	OB1	PSN
> NAME:           Robert L.
> Laney                                                         (50)						
> RL1	38.902	-77.38	OB2	PSN
> NAME:           Roberto E.
> Pozzo                                                        (38)						
> RP1	44.46	8.21	OB1	PSN
> NAME:           Roberto E.
> Pozzo                                                        (38)						
> RP2	44.46	8.21	JS1	PSN
> NAME:           Roger
> Griggs                                                           
> (6)							RG1	37.98	-121.72	OB1	PSN
> NAME:           Roger
> Sorensen                                                         
> (19)							RS1	34.16	-118.36	ES2	PSN
> NAME:           Roger
> Sorensen                                                         
> (19)							RS2	34.16	-118.36	JS3	PSN
> Name:           Ron
> Westfall                                                           
> (42)							RW1	49.325	-122.996	OB2	PSN
> NAME:           Southland Boys High
> School                                         (60)							SHS	-46.5
> 168.2	SJ1	PSN
> NAME:           Stephen
> Mortensen                                                      
> (55)							SM1	38.828	-120.978	OB1	PSN
> NAME:           Steve
> Clark                                                            
> (24)							SC1	44.99	-122.96	JS1	PSN
> NAME:           Steve
> Hammond                                                          
> (18)							FSX	37.245	-121.815	OB2	PSN
> NAME:           Steve
> Hammond                                                          
> (18)							FSZ	37.245	-121.815	JS3	PSN
> NAME:           Tom
> Frey                                                               
> (26)							LK1	47.17	-122.49	OB1	PSN
> NAME:           Tony
> Potenzo                                                           
> (46)							TP1	19.723	-155.991	OB1	PSN
> NAME:           Tony
> Potenzo                                                           
> (46)							TP2	19.723	-155.991	JS1	PSN
> NAME:           Walt
> Catino                                                            
> (29)							WC1	45.42	-123.04	SL2	PSN
> 
> _____________________________________________________________________
> 
> Public Seismic Network Mailing List (PSN-L)
> 
> To leave this list email listserver@............. with the body of the 
> message: leave PSN-L

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From: Doug Crice 
Subject: Corvettes
Date: Wed, 29 Jul 1998 11:56:37 -0700

Sean:

I find it difficlut to believe that someone who builds a world class
seismograph from scratch can't machine a set of brake callipers from
scrap laying around the lab  :)
-- 
Doug Crice          web site http://www.georadar.com
GeoRadar Inc.             e-mail dcrice@............
19623 Via Escuela Drive           phone 408-867-3792
Saratoga, CA 95070 USA              fax 408-867-4900



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From: Hubert Vroomen 
Subject: Re: More surplus geophones & etc.
Date: Wed, 29 Jul 1998 21:29:44 +0200

Hello Meredith,

I did not find information on the allcorp geophones on their web-site. As I
do not want to download the whole 3.2 MB catalog, can you give me a small
clue where to find this info (I looked at their chapter "transducers" and
some other chapters but didn't find anything)

Thanks,

Hubert

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From: S-T Morrissey 
Subject: Askania gravimeter
Date: Wed, 29 Jul 1998 15:19:10 -0500 (CDT)

Hubert,
We do have an unidentified object that is reported to be a gravimeter
in a large (.5m x .5m x1m) gimballed case for ship-born operation.
It is in my underground test (munitions) vault; I have never looked into just
exactly what instrument is in there. rumor has it that it may be
an old optical Worden instrument. I have to go to the remote site next
week (lightning zapped the telemetry from it), so I can look into it.
Unfortunately, I have no literature on it. The only Ascania info I have
is on their borehole tiltmeter, with the hip-hop ball calibration.

Thanks for your other comments. For the barometric compensation volumes,
we need to keep the mass as minimal as possibe, since the added mass
changes the center of gravity of the boom.  Any glass container would
have to be vary light.

I have considered using the terrarium inverted as a cover over the sensor 
and sealed to a baseplate on the pier surface. The STS-1 is set up this 
way; the 2cm thick pyrex baseplates of the instruments are vacuum-grouted 
to the pier surface, and the large glass bell jar sits on large circular
flat gaskets that are sealed by the atmospheric pressure when the bell is
evacuated. The cable/connector is through a hole bored in the edge of
the glass plate. For the homemade seis, I do not know if I can make a
useful seal to the large tiles on top of the pier, so I am considering 
epoxing a large acrillic plate to the pier surface to accomplish a 
similar result.
However, I would not want a permanent seal for the cover, since the it
needs to be removed to work on the seis. So the hunt is on for a suitable flat
gasket or weatherstrip that can be made pressure tight. McMaster has
a large selection of such, if the local hardware stores don't.

I may try the aquarium heater in a large container of fine sand rather
than water to avoid the humidity problem.

regards,
Sean-Thomas

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From: Karl Cunningham 
Subject: Re: period/mass etc of STM/ Nitinol actuators
Date: Wed, 29 Jul 1998 13:45:45 -0700

Another thought about centering..

It seems that using the motor approach of Sean-Thomas has some advantages
-- it contributes very little noise and heat when not in use, and it
doesn't drift much.  For those not happy with mounting the motor on the
boom, how about a very small-geometry flexure (spring) which would extend
down from the area of the other flexures to the baseplate and be deflected
by a nut on a motor-driven lead screw.  This small flexure would bend and
provide a restoring force that is adjustable using the motor.  I think the
reduction in natural period due to the addition of this flexure could be
compensated for by an adjustment of the leaf spring position.  As in
Sean-Thomas' approach, a periodic evaluation of the centering of the system
could be used.

Just another $.02

                                                           \
          |------------------------------------------------/
          |         Boom                                   \
   |-----|+-+----------------------------------------------\ 
   |     |  |                                              /
   |     |  |
   |     |  | New Flexure
   |     |  | 
   |     |  |
   |     |  |  Lead
   |     |  |  Screw  |-------|
   |     | x=xxxxxxxx-| Motor |-
   |     |  |         |-------|                         
   |     |             /\   /\                   BASE
----------------------------------------------------------------------------
-----


Karl Cunningham
La Mesa, CA.
PSN station #40
karlc@.......

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From: Greg 
Subject: Re: More surplus geophones & etc.
Date: Wed, 29 Jul 1998 14:27:58 -0700

Hubert Vroomen wrote:

> clue where to find this info (I looked at their chapter "transducers" and
> some other chapters but didn't find anything)

I looked through a large portion of the "chapters" and didn't find it.
It would have probably been quicker to download the whole thing for me
;) I'm all set for geophones, but I little curious.

,Greg

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From: Hubert Vroomen 
Subject: Re: period/mass etc of STM/ Nitinol actuators
Date: Wed, 29 Jul 1998 23:34:18 +0200

Karl,

I had been thinking about an idea like yours, but thought it might add to
much stiffness to the whole system (shortening the period). Perhaps I
overestimate this effect. I forgot to calculate the exact numbers, but I
think that the range of torque that is needed for thermal adjustment is
quite large (Sean-Thomas speaks about a 10 gram mass over a 10 inch
travel). This would mean that in your concept you either have a flexure
that is stiff (and you don't want that, see above) with small travel or a
flexible flexure with a large travel (which gives problems with kinematics
and non-linearities). 

I would like to repeat my previous idea, borrowing your picture, so it
might be a little clearer:

         |-------------------------------------------------MMMMMM
         |         Beam                                   MMMMMM Mass
   |-----+-----------------------+-------------------------MMMMMM
   |     | pivot        upper    |  ****
   |  S  | flexures     mounting | *    *
   |  u  |                       |*      *
   |  p  |                                *   Zero-length
   |  p  |                                 *  leaf-spring
   |  o  |                                 *
   |  r  |                                 *
   |  t  |   possible motion   <--->      *
   |     |          of           |*      *             
   |     |              lower    | *    *
   |     |              mounting |  ****      Base
---+-----+-----------------------+------------------------------------------

By variing the possition of the lower mounting the moment/torque of the
springforce around the axis of the flexures can be changed, and therewith
the restoring force for the vertical motion of the mass.

Perhaps it is a little bit clearer now, and thanks again for the wonderfull
ASCII art!

regards,

Hubert

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From: Hubert Vroomen 
Subject: Re: Askania gravimeter
Date: Thu, 30 Jul 1998 00:03:45 +0200

Hello Sean-Thomas

>We do have an unidentified object that is reported to be a gravimeter
>in a large (.5m x .5m x1m) gimballed case for ship-born operation.

If it is a round container, with about the dimensions you said, and the
axis of the cylinder in the horizontal plane, it could very well be an
Askania/Bodenseewerke. In my memory all Worden instruments have been
vertical cylinders, with three feet under it for support. And I do not know
of a ship-borne Worden.

At one end of the container you will find the electrical connections and a
measuring microscope. If it is one of the newer instruments (but if it is
on a gimballed platform it probably is not, newer systems are
gyro-stabilised) you will find a gear coming out of the container, with
perhaps an electric motor attached to it (this motor is missing at my
instrument). This motor was used for automatic zeroing (using the signal of
a differential photo-cell) during automatic recording on-sea.

>It is in my underground test (munitions) vault; I have never looked into just
>exactly what instrument is in there. rumor has it that it may be
>an old optical Worden instrument. I have to go to the remote site next
>week (lightning zapped the telemetry from it), so I can look into it.
>Unfortunately, I have no literature on it. The only Ascania info I have
>is on their borehole tiltmeter, with the hip-hop ball calibration.

I am not sure whether this system was also used for the calibration of this
gravimeter. I think it was, I once spoke with the inventor of this gadget,
and he still was very proud about it (no idea why, I still think it is a
funny way of calibrating, but whatever). I am reluctant to open the case of
my gravimeter, as it is a very delicate instrument and I am afraid of
destroying anything without having the proper documentation. BTW the
Askania/Bodenseewerke instruments live under many different names
(KSS5/GSS2/GSS20 and some more that I forgot, mine is a GSS2 which was
(partly) modified to GSS20 standard).

>Thanks for your other comments. For the barometric compensation volumes,
>we need to keep the mass as minimal as possibe, since the added mass
>changes the center of gravity of the boom.  Any glass container would
>have to be vary light.

I know, but glass can be pretty light. And you can use a glass ball (hey,
what about a christmas tree ball! Some of them are airtight and even
evacuated!).

>I have considered using the terrarium inverted as a cover over the sensor 
>and sealed to a baseplate on the pier surface. The STS-1 is set up this 
>way; the 2cm thick pyrex baseplates of the instruments are vacuum-grouted 
>to the pier surface, and the large glass bell jar sits on large circular
>flat gaskets that are sealed by the atmospheric pressure when the bell is
>evacuated. The cable/connector is through a hole bored in the edge of
>the glass plate. For the homemade seis, I do not know if I can make a
>useful seal to the large tiles on top of the pier, so I am considering 
>epoxing a large acrillic plate to the pier surface to accomplish a 
>similar result.
>However, I would not want a permanent seal for the cover, since the it
>needs to be removed to work on the seis. So the hunt is on for a suitable
flat
>gasket or weatherstrip that can be made pressure tight. McMaster has
>a large selection of such, if the local hardware stores don't.

I understand. I once had to build a small vacuum chamber at work, and I
used a steel baseplate with the electrical cables epoxied in it (we removed
the insulation at the pass-through to create a better airlock and forced
epoxy into the free ends of the cables to close them even more. You can
drink like a straw through about 3 meters of RG58 coax cable, no problem!).
Over it we placed a simple bell-jar. For evacuation we used a airco-pump,
it was the cheapest way to achieve reasonable vacuum.

If I were to be to build a pier, I would integrate into the pier a steel or
aluminium rim around the seismometer, of sufficient height to make some
pass-throughs for cables and with an upper surface to mate the terrarium,
either via some silicone or a solid gasket. It is probable much easier to
do this when you are building then afterwards, but you could also try to
mount such a rim to your pier with silicone. It will be not as mechanically
stable, but who cares.

I do not think that you need a baseplate, in my opinion it must be feasible
to seal the terrarium or the rim to the tiles, just use enought silicone
(it is called different in the States, but I forgot the correct name).

>I may try the aquarium heater in a large container of fine sand rather
>than water to avoid the humidity problem.

be careful, the conduction of heat to the sand is less than to the water,
it might destroy your heater.

regards,

Hubert

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From: meredith lamb 
Subject: Re: More surplus geophones & etc.
Date: Wed, 29 Jul 1998 15:04:18 -0600

Hubert,

All Electronics corp., has an email address for catalog request
or....questions:  allcorp@...........   The geophone is on the
last page (pg 96), but it lacks alot of detail.  Probably the best
route is too email and ask.  I emailed a questionaire afew minutes
back...but with all things, we maybe lucky to get an answer.
Lacking that for the present, the only info I have is:.....

Walt Williams information of afew days back:

Walt Williams wrote:

> Hi Meredith & All,
>
> I recently bought several Geosource MD-81, 10 Hz geophones from the
> Van Nuys, California, USA, store. They are packaged exactly the same
> as the Gateway supplier, but are slightly less expensive. Mostly
> same type. They have same diagram and a little perfboard with a LM393
> quad comparator and some resistors. You solder together to make
> simple circuit with red LED.
>
> I put my Tek-465B with x1 probe, 5 mv channel setting directly on
> geophone pins, place on rug (simple low-pass filter :-), lots of 60
> Hz, but works pretty good! I can see cars and trucks passing maybe
> 60 meters from house. Can see cat walking in kitchen, making din din
> run -- no amplifier, surprisingly sensitive! One of the nice folks
> (Roger Sorenson) on PSN sent me TurboCAD layout for geophone amp he
> built, I have hacked that up and made a simple test circuit, works
> well. This is very interesting, lots of good ways to spend boring
> nights!
>
> Cheers,
>
> Walt Williams, 98.07.27
> dfheli@..............
>
>
> Bob Lambs info:
>
> Bobs purchase geophone was a 10hz, 600 ohm, which he
> claims are much more sensitive than the Startronics (Arizona) model
> (14hz) ...roughly by ~8X signal.  Size, 1.6" height X 1.2" diameter.
> Bob is a retired electronics engineer.
>
>

The geophone is not with the transducers.  It looks like a last minute
throw on, on the last page, which was partially used for the mailing
label.  They are used functioning units.  There is more info here, than
on their ad.  Walt says they were "mostly same type", which means more
than one type of course.

If they email me back, I'll put on the PSN email.

Meredith Lamb


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From: Hubert Vroomen 
Subject: STS-1 vacuum-grouting
Date: Thu, 30 Jul 1998 00:35:22 +0200

Sean-Thomas and others,

>I have considered using the terrarium inverted as a cover over the sensor 
>and sealed to a baseplate on the pier surface. The STS-1 is set up this 
>way; the 2cm thick pyrex baseplates of the instruments are vacuum-grouted 
>to the pier surface, and the large glass bell jar sits on large circular

something I have been wanting to ask for a long time :-), what exactly is
vacuum-grouting, and why/how is it done. Is it because of air-bubbles in
the grout under the plate that would cause the plate to warp and tilt at
variing atmospheric pressures? Would it be an advice for future amateur
pier-builders, to top their piers with a plate of glass (as thick as
possible) put into a thick layer of grout/concrete?

I know that here in Germany it is possible to get old pieces of safety
glass from banks (many centimeters thick) for almost nothing, so this could
be a nice pier-top.

I still believe you do not need a real baseplate, just try without it,
simply use the terrarium upside-down (I admit, I just can't wait for
pressure-compensated results from the STM-8)!

regards, and thanks for this continuing interesting discussion,

Hubert

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From: "Charles R. Patton" 
Subject: Re: STS-1 vacuum chamber mouting idea
Date: Wed, 29 Jul 1998 16:34:19 -0700

Previous posts:
>I have considered using the terrarium inverted as a cover over the senso=
r=20
>and sealed to a baseplate on the pier surface.

I couldn=92t resist a comment on a possible method of mounting that would
tend to be pressure insensitive and could be easily used on any floor.=20
How about taking a rigid pipe section =96 maybe 1" to 2" in diameter and
making a pier feedthrough to the actual base plate. Then make your
vacuum plate float on that.  Something like this:

..  +------------------+
..  |                  |  <---Box over Seismometer
..  |                  |       and internal pier
..  |    seismometer   |      (Vacuum chamber
..  |  +------------+  |
..  |  |////////////|  |
..  |  +----+ +-----+  |
..  |       |/|        |
..  |       |/|        |
.. +------+ |/| +-------+
.. |\\\\\\| |/| |\\\\\\\|  Floating plate siliconed
.. +------+ |/| +-------+   on to pier riser
..          |/|
..          |/|
..     +----+ +-----+=20
..     |////////////| Baseplate with adjusment screws
..     +----+-+-----+=20
XXXXXXXXXXXXXXXXXXXXXXXXXXX  Floor or bedrock

Now, even though the vacuum plate flexes, it doesn=92t transmit bending
torque to the seismometer mounting.  The actual construction would be
quite simple.  A standard short nipple section screwed into two pipe
flanges would make the pier feedthrough.  Seal the pipe.  Screw on one
pipe flange, slip the vacuum chamber base plate on, then screw on the
other flange.  Attach two base plates =96 one inside for the seismometer
and one outside for the floor. =20

Charles R. Patton
charles.r.patton@........

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From: Hubert Vroomen 
Subject: Re: STS-1 vacuum chamber mouting idea
Date: Thu, 30 Jul 1998 02:19:00 +0200

Hello Charles and others,

You did draw:
>.  +------------------+
>.  |                  |  <---Box over Seismometer
>.  |                  |       and internal pier
>.  |    seismometer   |      (Vacuum chamber
>.  |  +------------+  |
>.  |  |////////////|  |
>.  |  +----+ +-----+  |
>.  |       |/|        |
>.  |       |/|        |
>. +------+ |/| +-------+
>. |\\\\\\| |/| |\\\\\\\|  Floating plate siliconed
>. +------+ |/| +-------+   on to pier riser
>.          |/|
>.          |/|
>.     +----+ +-----+ 
>.     |////////////| Baseplate with adjusment screws
>.     +----+-+-----+ 
>XXXXXXXXXXXXXXXXXXXXXXXXXXX  Floor or bedrock

I think this could be a good idea. Although a 1" or 2" might be a little
bit to flimsy, it is very well possible to use a larger post or (would be
my favorite) use longer and larger adjustment screws and omit the lower
baseplate, floating the "vacuum plate" to the adjustment screws. I suppose
that this is the kind of construction that Sean-Thomas is thinking about.

Not using any baseplate, either floating or fixed, and sealing the pressure
container to the pier is even simpler off-course, but demands a proper
finish of the pier-top (see my previous mail).

not long 'till we overtake the commercial instruments :-),

regards,

Hubert

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From: Brian Chesire 
Subject: Re: MEK to remove glue
Date: Wed, 29 Jul 1998 17:37:53 -0700

There are two chemicals that will slowly disolve cured epoxy. I've used
them both, maybe I can remember how to spell them.
 1.) Methylene Chloride: Probably on the EPA banned list. I know we
can't even mention it at work anymore.
 2.) Crescylic Acid: Will attack most anything organic. Used as a carbon
dissolver in Bendix "Solv-A-Seal", a 5 gallon bucket with a basket to
hold parts and a layer of oil on top to prevent evaporation, found in
almost all aircraft piston engine shops, also a major ingredient of auto
parts store dip type caburetor cleaner, Found in one gallon cans at my
local parts store. The best teacher is pain, DO NOT, stick your fingers
through the oil layer to find out whats under it. Took about 4 months
for the fingernails to grow back, OUCH.(I was only 12 and not too
bright!!)

Brian WA5PPO
Tucson, AZ

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From: David Josephson 
Subject: Re: MEK to remove glue
Date: Wed, 29 Jul 1998 18:11:47 -0700 (PDT)

> There are two chemicals that will slowly disolve cured epoxy. I've used
> them both, maybe I can remember how to spell them.
>  1.) Methylene Chloride: Probably on the EPA banned list. I know we
> can't even mention it at work anymore.

Available in most hardware stores as regular paint stripper.

>  2.) Crescylic Acid: Will attack most anything organic. Used as a carbon
> dissolver in Bendix "Solv-A-Seal", a 5 gallon bucket with a basket to
> hold parts and a layer of oil on top to prevent evaporation, found in
> almost all aircraft piston engine shops, also a major ingredient of auto

Aka "Turco" and still in aircraft engine shops. May take overnight
to eat epoxy, but it does.

-- 
David Josephson / Josephson Engineering / San Jose CA / david@.............

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From: barry lotz 
Subject: Re: mass buoyancy
Date: Wed, 29 Jul 1998 17:45:49 -0700

Sean Thomas
   I too can't find my calcs, so I ran thru them again. I tend to write
everything on the backs of envelopes. Anyway, for a say 10 degree F temp
change I got an about 2 mg bouyancy. I put a 70mg weight on my sensor
and got a 1.5 vt output . This leads to a 50 mv change. It isn't that
much.
                                          Barry

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From: barry lotz 
Subject: Re: STS-1 vacuum chamber mouting idea
Date: Wed, 29 Jul 1998 17:56:00 -0700

Hi All
   I would be careful about subjecting a flat sided glass terrarium to a
14 psi external pressure(vacuum). Round maybe, where the stresses are
axial. Implosion! If it has been done I would like to know, so I would
be a little less conservative.
                                    Barry

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From: meredith lamb 
Subject: [Fwd: Geophone on sale]
Date: Wed, 29 Jul 1998 20:11:36 -0600


Meredith,

The geophones are made by Geosource Inc., Model # MD-81.  They were
manufactured in 1985 and appear to have been used.  They measure 616 ohms
across the coil.
Guaranteed functional.  That's all we know.

All Electronics Corp



>Sir:
>
>Request more information on your geophone on sale per your
>catalog....pg 96.  Who is the mfgr, model, resistance etc.?  Is
>there more than one type?
>
>Thanks, Meredith Lamb


                ============================================
                        . . . .  . . . . .  . . . . . .
                        . email - allcorp@........... .
                        .   www  and on-line store    .
                        .   http://www.allcorp.com/   .
                        .      phone toll free        .
                        .        888-826-5432         .
                        .     fax 818-781-2653        .
                        . . . . . . . . . . . . . . . .

                ============================================




From: S-T Morrissey 
Subject: vacuum grouting; pier sealing
Date: Thu, 30 Jul 1998 01:17:17 -0500 (CDT)

Hubert and co,

The vacuum grouting of the baseplates of the STS-1 seismometers
is intended to remove air from the grout and from under the glass
baseplate. First a grout slurry is poured in a shallow form and
a 2 ft dia steel dome is placed over it and sealed to the pier with
a very compliant gasket. A dry vane pump then evacuates the dome and
pulls the bubbles out of the grout, which is enhanced with latex
bonding and sealing additives.
Then the glass baseplate is placed in the grout and worked down
about 1 cm, and the steel dome is replaced and again evacuated 
until no further bubbles are evident. This commits the instrument
to a permanent installation.

On the other hand, for the STM designs, I would like to avoid an
installation that cannot be easily modified or relocated, at
least for the present. We need to keep things simple, and while
being acutely aware of potential noise sources, realize that most
practical sites will not warrant ultimate low noise designs. 
So I will be more inclined to work on more "portable" ideas.
The sealed commercial seismometers, especially
the STS-2, incorporate an integral baseplate that is mechanically
isolated from the containment vessel, somewhat along the ideas
just presented here by George P., except on a smaller scale. 

Likewise, I do not think we need to pursue evacuated containment;
we can speculate on the possibilities, but it can also be dangerous.
A containent that has a pressure time constant of several hours will
adequately solve our barometric noise problems.

Regards,
Sean-Thomas

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From: Karl Cunningham 
Subject: Re: period/mass etc of STM/ Nitinol actuators
Date: Thu, 30 Jul 1998 08:16:49 -0700

Hubert --

Thanks for your comments.  I missed the concept of how much correction
Sean-Thomas needed.  Thanks for pointing that out.  It seems that your
method may not affect natural period since it should only change the vector
of the spring's force, and therefore only the mechanical advantage (gain)
of the spring.  I am curious if anyone has equations that describe the
characteristics of a leaf spring when used in this manner.  



Karl Cunningham
La Mesa, CA.
PSN station #40
karlc@.......

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From: Norman Davis WB6SHI 
Subject: Re: aquarium heater?
Date: Wed, 29 Jul 1998 07:17:24

At 08:08 PM 7/28/98 -0500, you wrote:
>Hubert,
>I forgot to mention the plan C for temperature: to put an
>aquarium heater in a large (liter+) jar of water inside the
>seis case. They control within a degree F, and the jar of
>water would average out the cycling of the heater. Maaybe
>the heater can be broken into to refine its sensitivity.

 I was into that stuff a while back and they make a electronic control
heater that is quite accurate and may do the job for you. BTW that is a
slick idea if it provides the amount of heat you need.

My problem is a lizard that likes to bathe in the mineral oil. Looks like a
7.0 every time he gets into it. Looks like it is time for magnetic damping...


Norman Davis WB6SHI
Shingle Springs, Ca
normd@.............
http://www.directcon.net/normd/index.htm


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From: S-T Morrissey 
Subject: bimetallic thermal comp
Date: Thu, 30 Jul 1998 19:36:06 -0500 (CDT)

re: bimetallic thermal compensation

I have finally implemented plan D for temperature compensation.
This involves extracting the coiled bi-metallic element from a
large cheap dial thermometer, attaching a new central shaft to the
center of the coil (a 0.010 slit in a piece of 1/16" rod, glued
with epoxy), and straightening our about 6cm of the outer
end. 
For a trial installation, the central shaft is clamped to
the boom about 5 cm toward the hinges from the support post, and 
the extended end applies a force to the underside of the 1/4" boom 
clamping bolt. The bimetallic element curls clockwise from the
center, and closes tighter with increasing temperature. So an increase 
in temperature winds up the element, applying less force to the
underside of the support post, allowing the boom to rise. This
compensates for the drop in boom position that results from warming
the main leaf spring. One can test it by breathing on the bimetallic
coil, which makes the boom rise.

Of course, the first evaluation is whether this adversely affects the 
overall performance of the seis. Since the contact of the bimetallic
element with the support post bolt is a metal-metal surface, some
stiction steps might be observed, although I have not seen any. THis
contact will be replaced with a small flexure made with a loop of
nylon thread to allow free differential motion.

To adjust the effectiveness of the compensation, the clamp of the 
central shaft is rotated to apply more or less pressure by the 
free extended end on the fixed bolt.
Since the bimetallic element is actually a temperature dependent spring,
this will increase or decrease the compensation effect.

Does it work? It seems to. I just turned it for more compensation,
and as the box cools off, the DC trend is now negative, indicating
over-compensation. Now I need to log the DC mass position voltage
wrt. temperature to see how effective it is in the long run.
I suppose that to properly adjust it some switchable artificial 
heat source will have to be used, like a small light bulb.

Regards,
Sean-Thomas

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From: taber@............. (John Taber)
Subject: Re: What is the destructive range of an earthquake?
Date: Fri, 31 Jul 1998 12:52:24 +1200



Ashley Neal Hornbeck asked:

>Is there a rule-of-thumb attenuation equation for earthquakes?
>
>In other words:
>If I'm x miles away from the epicenter of M7.0.
>That would be equivalent to being directly above the epicenter of a M y.
>Where:
 >x is distance
 >y is magnitude
>

As Sean-Thomas explained the attenuation varies with tectonic regions, so 
there are a range of attenuation expressions that have been 
determined from different data sets.

An example by Joyner and Boore (1981) for the western US is

log y = -1.02 + 0.249M -log r -0.00255r

where 

y = peak horizontal acceleration in g (decimal fractions of gravity)
r = shortest distance to the fault in km
M = surface wave magnitude

If I've done my algebra right, that means being

10 km away from a magnitude 6 (0.28g) is about the same as being
17 km away from a magnitude 7.  

Cheers,

John 


John Taber		School of Earth Sciences, Victoria University
John.Taber@.............. Box, 600, Wellington, New Zealand


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From: barry lotz 
Subject: Re: bimetallic thermal comp
Date: Thu, 30 Jul 1998 19:40:46 -0700

Sean Thomas
   Thats the best temp compensation device I've heard yet. Simple. I
like it.
                                      Barry

>S-T Morrissey wrote:
> 
> re: bimetallic thermal compensation
> .....

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From: "Al Allworth" 
Subject: RE: bimetallic thermal comp
Date: Thu, 30 Jul 1998 22:19:38 -0700



> -----Original Message-----
> From: S-T Morrissey [mailto:sean@............
> Sent: Thursday, July 30, 1998 5:36 PM
> To: psn-l@.............
> Subject: bimetallic thermal comp
>
>
> re: bimetallic thermal compensation
>


Another thought for the group,

Why not plate copper on one side of the spring. I think this would be the
elegant
solution. Copper plating can be done easily in the home shop / lab and
should be
repeatable once the desired effect is achieved.

								Al


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From: Steve Hammond 
Subject: updated PSN station list
Date: Thu, 30 Jul 1998 22:49:47 -0700

This is the station list with your map ID number is a new listing. All
names without (xx) are new stations added to the list.
This has already been submitted to Steve Malone for the Council of the
National Seismic System Assessment and IASPEI Handbook.
Regards, Steve Hammond 


  Field 1
          Station Operator ID
  Field 2
          Latitude        Longitude
  Field 3
          XXX  see legend  (1st,2nd,3rd charachter
 
  1st charachter
 
          J = Short period <10 seconds
          O = Long-period >10 seconds
          E = Accelerometer
 
  2nd charachter
          S = Short period corner <10 seconds
          B = Broad Band 10 to 89 seconds
          H = smoke / chart recorder >80 seconds
 
  3rd charachter
 
          Number of orientations (ie 1-single channel)


1 NAME:           Al Allworth     W7PXX    (51)      AA1 42.51 -124.33
JS1
2 Name:           Almaden Country Middle School      ACS 37.12 -121.5
OB1
3 NAME:           Albert Judge  (Alby)     (37)      AJ1 -32 115
OB1                                     
4 NAME:           Arie  Verveer            (59)      AV1 -32.0083
116.1346 OB2
5 NAME:           Bob Hammond              (13)      BH1 64.921 -147.937
JH1
6 NAME:           Bob Hammond              (13)      BH2 64.921 -147.937
OH1
7 NAME:           Barry Lotz               (15)      BL1 39.23 -121.07
OB1
8 NAME:           Bill Scolnik             (28)      BS1 41.05 -74.25
JS1                                     
9 NAME:           Bill Scolnik             (28)      BS2 33.5 -74.25
OB2                                    
10 NAME:           Bob Teller               (9)      BT1 46.19 -111.3
OB3
11 NAME:           Charlie Thompson        (10)      BUE 30.112 -97.891
OB2
12 NAME:           Brian Zimmerman         (16)      BZ1 41.875 -80.125
JS1
13 NAME:           Brian Zimmerman         (16)      BZ2 41.875 -80.125
OB2
14 NAME:           Claudio Conti           (58)      CC1 37.035 15.135
OB1
15 NAME:           Claudio Conti           (58)      CC2 37.035 15.135
SJ3
16 Name:           Clark Wockner           (43)      CW1 40.78 -87.75
OB1
17 NAME:           Darrell Collins         (27)      DC1 33.5 -111.9
JS1                                   
18 NAME:           Darrell Collins         (27)      DC2 33.5 -111.9
OB2                                   
19 NAME:           Malcolm Sinclair        (32)      DHQ -45.6 170.4 JH1
20 NAME:           Dennis Leatart           (8)      DL1 34.1 -118.88
JS1
21 NAME:           Douglas McConnell       (49)      DM1 -30.317 149.988
OH1
22 NAME:           Dave Nelson     ZL4TBN   (4)      DN1 -45.8 170.3 JS1
23 NAME:           Dave Nelson     ZL4TBN   (4)      DN2 -45.8 170.3 JS1
24 NAME:           Dave Nelson     ZL4TBN   (4)      DN3 -45.8 170.3 JS1
25 NAME:           Dave Nelson     ZL4TBN   (4)      DN4 -45.8 170.3 OB1
26 Name:           Donald Sieber (retired) (47)      DS1 43.61 -116.21
JS1
27 NAME:           Fred Bruenjes            (2)      FB1 32.822 -117.084
OB1
28 NAME:           Fred Bruenjes            (2)      FB2 32.822 -117.084
OB1
29 NAME:           Frank Cooper    W5VID   (20)      FC1 29.52 -95.17
OB1
30 NAME:           Bob Lewis    WB5FDF     (39)      FD1 33.1 -96.43
OB1                             
31 NAME:           Bob Lewis    WB5FDF     (39)      FD2 33.1 -96.43
JS1                            
32 NAME:           Francesco Nucera        (53)      FN1 -43.29 13.29
OS1
33 NAME:           Francesco Nucera        (53)      FN2 -43.29 13.29
JS2
34 NAME:           Francesco Nucera        (53)      FN2 39.96 -82.98
OB1
35 NAME:           Steve Hammond           (18)      FSX 37.245 -121.815
OB2
36 NAME:           Steve Hammond           (18)      FSZ 37.245 -121.815
JS3
37 NAME:           David Wolny             (34)      GJC 39.079 -108.554
OB1
38 NAME:           Gregory A. Lyzenga       (7)      GL1 34.2 -118.13
OB1
39 NAME:           Giovanni Rotta          (45)      GR1 46.22 13.18 JB1
40 Name:           Grayling School, Alaska           GRY 62.8 -160.1 OH1
41 NAME:           South Valley Jr. High             GS1 37 -121.6 OB1
42 Name:           HSC;  Fairbanks, Alaska           HSC 62.8 -160.1 OH1
43 NAME:           Jeff Batten             (25)      JB1 34.13 -118.12
JS2
44 NAME:           Jeff Batten             (25)      JB2 34.13 -118.12
OB1
45 NAME:           Jeff Batten            (25)       JB3 34.13 -118.12
JH1
46 NAME:           Jean-Jacques Hunsinger (41)       JCH 47.5 7 OB1
47 NAME:           Jerry Darby                       JD1 36.65 -119.3
OB1
48 NAME:           Jim Lovell             (22)       JL1 -43.52 172.61
OS1
49 NAME:           Jack Sandgathe         (23)       JS1 49.35 -119.62
OB1
50 NAME:           Karl Cunningham        (40)       KC1 32.7705
-116.97775 JS1
51 NAME:           Karl Cunningham        (40)       KC2 32.7705
-116.97775 EH1
52 NAME:           Karl Cunningham        (40)       KC3 32.7705
-116.97775 OB1
53 NAME:           Kim Froom                         KF1 34.9 -121.45
OB1
54 NAME:           Ken Navarre            (21)       KN1 37.39 -121.99
OB1
55 NAME:           Kees Verbeek           (12)       KV1 51.26 5.3 JH1
56 NAME:           Larry Cochrane          (1)       LC1 37.496 -122.241
OB1
57 NAME:           Larry Cochrane          (1)       LC2 37.496 -122.241
JS3
58 NAME:           Larry Cochrane          (1)       LC3 37.496 -122.241
OB1
59 NAME:           Lucas Haag             (11)       LH1 40.13 -100.29
JS1
60 NAME:           Tom Frey               (26)       LK1 47.17 -122.49
OB1
61 NAME:           Liberio Rossi          (56)       LR1 43.54 10.34 JS3
62 Name:           Martin S. Brewer       (44)       MB1 32.278 -64.793
OB2
63 Name:           McGrath School, Alaska            MCG 62.9 -155.6 OH1
64 NAME:           Mark Halliday           (5)       MH1 37.085 -122.106
JS1
65 NAME:           Mark Halliday           (5)       MH2 37.085 -122.106
OB1
66 NAME:           Meredith Lamb          (52)       ML1 39.703 -105.006
OB1
67 NAME:           Meredith Lamb          (52)       ML2 39.703 -105.006
OB1
68 NAME:           Meredith Lamb          (52)       ML3 39.703 -105.006
OB1
69 NAME:           Malcolm Sinclair       (32)       MS1 -43.55 172.68
JH1
70 Name:           Pearl Creek School, Alaska        PCK 64.9 -147.8 OH1
71 NAME:           Paolo Frediani         (57)       PF1 44.13 10.06 SJ2
72 NAME:           Paolo Frediani         (57)       PF2 44.13 10.06 OB1
73 NAME:           Pete Rowe                         PR1 37.38 -121.79
JS1
74 NAME:           Robert (Bob) L. Barns   (3)       RB1 40.6802
-74.4142 OB1
75 NAME:           Roger Griggs            (6)       RG1 37.98 -121.72
OB1
76 NAME:           Robert L. Laney        (50)       RL1 38.902 -77.38
OB2
77 NAME:           Charlie Rond           (35)       RM1 35.041 -89.84
OB1
78 NAME:           Roberto E. Pozzo       (38)       RP1 44.46 8.21 OB1
79 NAME:           Roberto E. Pozzo       (38)       RP2 44.46 8.21 JS1
80 NAME:           Roger Sorensen         (19)       RS2 34.2711
-118.59386 JS3
81 NAME:           Dick Webb              (30)       RW1 35.54 -78.39
OB1
82 Name:           Ron Westfall           (42)       RW1 49.325 -122.996
OB2
83 NAME:           Steve Clark            (24)       SC1 44.99 -122.96
JS1
84 NAME:           Phil Giannini          (17)       SFX 37.72 -122.416
OB2
85 NAME:           Phil Giannini          (17)       SFZ 37.72 -122.416
JS1
86 NAME:           Sam Gazdik                        SG1 41.8 -123.2 OB2
87 NAME:           Southland Boys High School (60)   SHS -46.5 168.2 SJ1
88 NAME:           Stephen Mortensen      (55)       SM1 38.828 -120.978
OB1
89 NAME:           Phil Giannini          (17)       SMX 37.75 -122.2
JN3
90 NAME:           Phil Giannini          (17)       SMZ 37.75 -122.2
JN3
91 Name:           SRA,  Fairbanks, Alaska           SRA 62.8 -160.1 OH1
92 NAME:           Peter Styles, Sam Toon (36)       ST1 53.4 -2.96 JS1
93 NAME:           Ted Blank                         TB1 37.21 -121.85
OB1
94 NAME:           Tony Potenzo           (46)       TP1 19.723 -155.991
OB1
95 NAME:           Tony Potenzo           (46)       TP2 19.723 -155.991
JS1
96 NAME:           George Bush            (14)       TSR 38.74 -123.5
EH3
97 NAME:           Phil Giannini          (17)       TVN 37.75 -122.2
OB1
98 NAME:           Phil Giannini          (17)       TVZ 37.75 -122.2
JS1

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From: 
Subject: Geophones
Date: Fri, 31 Jul 1998 11:42:53 EDT

Hello,

Geophones are made in two different configurations, normal and reverse.  The
reverse geophones have the magnet reversed and coil wound in the opposite
direction in reference to the norman phones. They pick up seismic data in the
same phase.  However, any induced emf will be cancelled and therefore 60 hz
power interference is reduced.  They are made to be used in pairs or in an
array, where there will be the same number of normal and reverse geophones.
There is a marking on the geophone element denoting if the geophone is normal
or reversed.

I suggest those of you who are using the MD-81 Geosource vertical phone to use
two phones, one normal and one reverse either connected in parallel or in
series.

Good recordings,

George Erich
GeE777@.......
Seismic Exploration Consultant

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From: Doug Crice 
Subject: Re: Geophones
Date: Fri, 31 Jul 1998 09:25:54 -0700

George:

>From one old sage to another, I have been buying geophones for 25 years
and never heard about normal and reverse geophones.

I believe that modern geophones, including the MD-81, all have "dual
hum-bucking" coils where the geophone has two coils wound to respond to
external fields in equal and opposite polarities so the noise canceling
is internal.

Somebody with a little free time ought to buy a supply of 4.5 Hz phones
from Clark or Mitcham and then resell them individually to the group at
a modest cost.  Since there's so much interest in the 10 Hz phones, 4.5
would be better.  If we're patient, we might buy some 3-component 4.5 Hz
packages cheap.
-- 
Doug Crice          web site http://www.georadar.com
GeoRadar Inc.             e-mail dcrice@............
19623 Via Escuela Drive           phone 408-867-3792
Saratoga, CA 95070 USA              fax 408-867-4900


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From: Greg 
Subject: Re: Geophones
Date: Fri, 31 Jul 1998 10:00:28 -0700

Doug Crice wrote:

> Somebody with a little free time ought to buy a supply of 4.5 Hz phones
> from Clark or Mitcham and then resell them individually to the group at
> a modest cost.  

I checked into a group discount with one company. The volume discount is
well beyond the number of people on the list. Of course, that was just
one company.
I think I lost the original quote from the company, but it might just be
on the other operating system (Windows 95).

OK, I'll bite, who are Clark or Mitcham?

You'd think anyone that can afford to do that would probably just buy
one or two nice commercial instruments for themselves.

,Greg

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From: Doug Crice 
Subject: Re: Geophones
Date: Fri, 31 Jul 1998 10:16:50 -0700

R. T. Clark (405-751-9696) and Mitcham Industries (409-291-2277) are
dealers in used geophysical exploration gear, including seismographs
(exploration), magnetometers, gravimeters, cables, phones, etc.  I'm
sure that neither would welcome orders for individual geophones, but
would be happy to sell a pile of geophones to anybody willing to buy. 
Clark publishes a little flyer once or twice a year which might even
include some 1 Hz phones and an occasional drum recorder, but not at
scrap prices, more like 25 to 50 % of new cost.

They will test the geophones for you.

Seismic crews buy geophones in lots of 5 or 10 thousand, that's why the
quantity discount is our of our reach.  I haven't checked, but I would
guess that a new 4.5 Hz element would cost about $50.
-- 
Doug Crice          web site http://www.georadar.com
GeoRadar Inc.             e-mail dcrice@............
19623 Via Escuela Drive           phone 408-867-3792
Saratoga, CA 95070 USA              fax 408-867-4900


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From: Greg 
Subject: Re: Geophones
Date: Fri, 31 Jul 1998 10:27:37 -0700

Doug Crice wrote:

> guess that a new 4.5 Hz element would cost about $50.

There's one that someone on the list is using. I think it's the GeoSpace
GS-11D. It's about $70 from GeoSpace. They're the ones I asked about the
group discount with.

,Greg

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From: Greg 
Subject: Re: Geophones
Date: Fri, 31 Jul 1998 11:17:31 -0700

Doug Crice wrote:
 
> R. T. Clark (405-751-9696) and Mitcham Industries (409-291-2277) are

I found one anyway ;) http://www.mitchamindustries.com/ 
They have mostly 10Hz geophones from what I saw.

,Greg

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From: Edward Cranswick 
Subject: Re: Use this list -- PSN Station list
Date: Fri, 31 Jul 1998 13:02:57 -0600

Steve-
    That was a labor of love to get all the stations in the list (I
still don't quite grok the instrument description code, but I am working
on it: I downloaded the manual from the IRIS DMC).  Do you have any
thoughts about parts A & C?, i.e.,


> The following items are needed by the end of July:
>
> A.  Network Summary (questionnaire attached below)
> B.  List of stations
> C.  Draft of one paragraph "abstract"
>
I could help you out with something this weekend.
-Edward

Steve Hammond wrote:

> I found a clipped field in the other note--
> please use this list.
>  Steve,
>  PSN Station list attached below
>  Regards, Steve Hammond
>  ---------------------------------
>   Field 1
>           Station Operator
>   Field 2
>           Latitude        Longitude
>   Field 3
>           XXX  see legend  (1st,2nd,3rd charachter
>
>   1st charachter
>
>           J = Short period <10 seconds
>           O = Long-period >10 seconds
>           E = Accelerometer
>
>   2nd charachter
>           S = Short period corner <10 seconds
>           B = Broad Band 10 to 89 seconds
>           H = smoke / chart recorder >80 seconds
>
>   3rd charachter
>
>           Number of orientations (ie 1-single channel)
>



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From: Greg 
Subject: Rip it up or add to it
Date: Fri, 31 Jul 1998 13:12:51 -0700

There was the mention of a web page devoted to geophones as they relate
to PSN a while back. I didn't see anything yet, so I butted in and wrote
a FAQ. I'd appreciate your constructive and destructive comments on it. 

Email me at ghost@.............
The page is at http://www.treefort.org/~ghost/geo.html

It's fairly simple and without pictures. I tested some of the links and
some are from bookmarks. I almost know someone has a few more to add.

Thanks,
Greg

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From: Doug Crice 
Subject: Re: Rip it up or add to it
Date: Fri, 31 Jul 1998 16:33:15 -0700

Greg:

Nice FAQ.

Actually, it's the coil that moves, not the magnet.  You might want to
add a note about frequency response as related to natural frequency, and
mention that they are velocity sensors.

I doubt that Mitchan's web site is an accurate representation of his
inventory.  He's so busy leasing 1000-channel systems and fending off
the lawyers that such things are trivial.  I would give Rory Clark a
call, it's a nice little outfit.
-- 
Doug Crice          web site http://www.georadar.com
GeoRadar Inc.             e-mail dcrice@............
19623 Via Escuela Drive           phone 408-867-3792
Saratoga, CA 95070 USA              fax 408-867-4900



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From: robert barns <75612.2635@..............>
Subject: Re: period/mass etc of STM/ Nitinol actuators
Date: Fri, 31 Jul 1998 20:24:25 -0400

Hi gang,
  Larry Cochrane described in some detail the shaker tabel he built.  He
used a stepper motor.  Look thru the mail archives for this.
Bob Barns

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From: Robert Avakian 
Subject: Re: Geophones
Date: Fri, 31 Jul 1998 19:59:29 -0700

I missed the first post.  The old crews did worry about phone polarity. 
To reduce groundroll and inline noise, the phones were linked in a
series/parallel hookup.  To make sure phones were properly hooked up,
the two leads on each phone were of different widths, one wide, one
narrow.  These fit corresponding takeouts in the cables.  Despite this I
often found strings of phones clipped in backwards. 

I remeber, dimly, some of the companies, such as Pan American supposedly
had their phones wired "backwards" so that even their field records were
reverse polarity from every one else's.

Outside fields meant 60 "cycle" from power lines.  The cables were the
real problem - hroizontal and miles long.  60 Hz "notch" filters were
routinely used in the recording trucks in amy areas as we were
interested in 25 - 80 hz energy.  

Are any seismologists bothered by 60 Hz noise? 



 Doug Crice wrote:
> 
> George:
> 
> >From one old sage to another, I have been buying geophones for 25 years
> and never heard about normal and reverse geophones.
> 
> I believe that modern geophones, including the MD-81, all have "dual
> hum-bucking" coils where the geophone has two coils wound to respond to
> external fields in equal and opposite polarities so the noise canceling
> is internal.
> 
> Somebody with a little free time ought to buy a supply of 4.5 Hz phones
> from Clark or Mitcham and then resell them individually to the group at
> a modest cost.  Since there's so much interest in the 10 Hz phones, 4.5
> would be better.  If we're patient, we might buy some 3-component 4.5 Hz
> packages cheap.
> --
> Doug Crice          web site http://www.georadar.com
> GeoRadar Inc.             e-mail dcrice@............
> 19623 Via Escuela Drive           phone 408-867-3792
> Saratoga, CA 95070 USA              fax 408-867-4900
> 
> _____________________________________________________________________
> 
> Public Seismic Network Mailing List (PSN-L)
> 
> To leave this list email listserver@............. with the body of the
> message: leave PSN-L


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From: Hubert Vroomen 
Subject: short leave
Date: Sat, 01 Aug 1998 11:40:04 +0200

Dear friends,

because I will be away some time the next months, and do not have the
recources for a 1MB e-mail folder, I will leave this very interesting list
for a short period. I hope I will catch up via the archives and expect many
new and interesting things to have happened (Sean-Thomas !) when I
subscribe again (september/october this year or so).

In urgent cases :-) I can be reached under my personal account:
hubert@....................

Thanks alot for the interesting stuff (special thanks to Larry Cochrane for
all his efforts) and good-bye till autumn.

regards,

Hubert


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From: watson@................ (Charles Watson)
Subject: PSN Acknowledged
Date: Sat, 01 Aug 1998 08:54:39 -0700

The PSN was acknowledged in the Opinion section of the July/August 1998 
issue of the Seismological Research Letters.

-- 
---/----
Charles P. Watson
Seismo-Watch

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From: Larry Cochrane 
Subject: Re: PSN Acknowledged
Date: Sat, 01 Aug 1998 13:28:53 -0700

Charles,

Since most of us do not have access to the Seismological Research Letters,
can you tell us what it said?

Thanks,

-Larry Cochrane
Redwood City, PSN

At 08:54 AM 8/1/98 -0700, you wrote:
>The PSN was acknowledged in the Opinion section of the July/August 1998 
>issue of the Seismological Research Letters.
>
>-- 
>---/----
>Charles P. Watson
>Seismo-Watch


_____________________________________________________________________

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From: Edward Cranswick 
Subject: Re: PSN Acknowledged
Date: Sat, 01 Aug 1998 17:25:22 -0600

Larry-
    The article is available at

Interestingly enough, some of the references in it to earthquake prediction,
China and monitoring seismicity using public participation sound similar to
John Lahr's USGS Open-file report of 1978 and the AGU poster that Robert
Banfill and I presented in 1990.  Thanks to Charles Watson for pointing out
the reference.
-Edward

Larry Cochrane wrote:

> Charles,
>
> Since most of us do not have access to the Seismological Research Letters,
> can you tell us what it said?
>
> Thanks,
>
> -Larry Cochrane
> Redwood City, PSN
>
> At 08:54 AM 8/1/98 -0700, you wrote:
> >The PSN was acknowledged in the Opinion section of the July/August 1998
> >issue of the Seismological Research Letters.
> >
> >--
> >---/----
> >Charles P. Watson
> >Seismo-Watch
>
> _____________________________________________________________________
>
> Public Seismic Network Mailing List (PSN-L)
>
> To leave this list email listserver@............. with the body of the
> message: leave PSN-L



--
Edward Cranswick                Tel: 303-273-8609
US Geological Survey, MS 966    Fax: 303-273-8600
PO Box 25046, Federal Center    cranswick@........
Denver, CO 80225-0046  USA      E.M. Forster said, "Only connect".




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From: Edward Cranswick 
Subject: Re: [Fwd: Santa Cruz Seismic Instruction Software]
Date: Sun, 02 Aug 1998 15:53:11 -0600

Ted & Jan -
    I am looking forward to hearing what your plans are for a PSN poster at AGU this
December presented by high school students from Almaden School. Last Thursday, I gave
a short presentation about the PSN to the Education & Outreach (E&O) people from
USGS, and I gave them a handout that was somewhat cosmically connected to the subject
of education; see  ftp://groundmotion.cr.usgs.gov/PSN/PSN_summary.html
    Having a bona fide school connection has always been one of the Holy Grails of
the PSN. Steve Hammond and I were going to do a project with San Jose schools in
1994, but the hiccoughing of the Silicon Valley economy, the Northridge Earthquake,
and school system politics acted together to distract us from that goal.
    I know that you need to talk with the science teacher about the AGU poster, but I
would like a rough draft of the abstract within the next couple of weeks so that I
could run it by the USGS E&O people and get their response and, I hope, support,
before we submit it to AGU (deadline for submission to AGU is the end of August).
    I wish you luck in your preparations.
-Edward

PS. I am having some problems with emailing to the PSN-L, and sometimes I am not sure
whether I am coming or going; so my correspondence may be a trifle incoherent.

Ted Blank wrote:

> I will speak to my son's science teacher.  When I mentioned it to her
> last year she was very excited about the idea.  Thanks for proposing to
> sponsor us.
>
> Ted Blank
> San Jose, California
>
> On Thu, 23 Jul 1998, Edward Cranswick wrote:
>
> >
> >
> > --
> > Edward Cranswick                Tel: 303-273-8609
> > US Geological Survey, MS 966    Fax: 303-273-8600
> > PO Box 25046, Federal Center    cranswick@........
> > Denver, CO 80225-0046  USA      E.M. Forster said, "Only connect".
> >
> >
>
>   ------------------------------------------------------------------------
>
> Subject: Re: Santa Cruz Seismic Instruction Software
> Date: Thu, 23 Jul 1998 16:47:09 -0600
> From: Edward Cranswick 
> Organization: US Geological Survey, Golden, CO
> To: Jan Froom 
> CC: cranswick@...............
> References: <5030300023233283000002L032*@MHS>
>
> Jan-
>         I thought that you, Steve, and Ted might do something, and I think that
> I forwarded some kind of info to the PSN-L.  However, I was not really
> connected with it myself, and I wasn't going to try to tell you guys
> what you should do (what maybe I should have helped to do myself).  In
> any case, the IRIS meeting does not get as much coverage as the AGU
> meetin in San Francisco in December which Larry and Ted attended last
> year with me.  So I think it would be a great idea to pursue the idea
> that you and Ted talked about last year of having a bunch of students
> submit a poster for the AGU meeting 6-10 December this year
> . You guys can write the
> abstract and prepare the poster and I, as an AGU member, can sponsor it
> and get the USGS to pay for it. The abstract deadline for that is:
>
>         August 26, 1998         (Postal/express mail submissions)
>
>         September 2, 1998       (Interactive Web Form submissions)
>
>         Because we only have about a month, please let me know ASAP what you
> think and also CC a copy to me at  which what
> I am trying to make my address for PSN-related activities.
> -Edward
>
> Jan Froom wrote:
> >
> > It's a shame that we couldn't have gone to this conference, since I think
> > Steve, Ted & I  are about the only ones in this area that are actually working
> > with schools.... well Elementary, Middle & High.  I tried, and got a note from
> > a lady in Arizona that forwarded my request to a lady in Santa Cruz....  but
> > after that I got no answer.
> > ---------------------- Forwarded by Jan Froom/San Jose/IBM on 07-22-98 11:26 AM
> > ---------------------------
> >
> > Ted Blank
> > 07-21-98 01:13 PM
> > To: Jan Froom/San Jose/IBM@IBMUS
> > cc:
> > From: Ted Blank/Santa Teresa/IBM @ IBMUS
> > Subject: Re: Santa Cruz Seismic Instruction Software
> >
> > I tried to get the information from Larry but it was all very vague.  Finally
> > he called me the night before to say it was the next day but by that time I had
> > other plans.  Oh well.
> >
> > Regards, Ted
> > DB2 Performance, IBM Santa Teresa Lab, San Jose, California
> >
> > Ted Blank/Santa Teresa/IBM .....(from Notes)
> > IBMUSM50(TED) .............................(from PROFS/VM)
> > ted@.......... ..............................(from internet sites)
> > STLVM6(BLANK) .............................(for LIST3820 files etc.)
> > Tie: 8-543-3589    Ext:  (408) 463-3589   Fax:  (xxx-2614)
>
> --
> Edward Cranswick                Tel: 303-273-8609
> US Geological Survey, MS 966    Fax: 303-273-8600
> PO Box 25046, Federal Center    cranswick@........
> Denver, CO 80225-0046  USA      E.M. Forster said, "Only connect".



--
Edward Cranswick                Tel: 303-273-8609
US Geological Survey, MS 966    Fax: 303-273-8600
PO Box 25046, Federal Center    cranswick@........
Denver, CO 80225-0046  USA      E.M. Forster said, "Only connect".




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Public Seismic Network Mailing List (PSN-L)


From: Edward Cranswick 
Subject: test: PSN-L Mailing List 
Date: Sun, 02 Aug 1998 18:29:08 -0600

PSN-L Mailing List 

--
Edward Cranswick                Tel: 303-273-8609
US Geological Survey, MS 966    Fax: 303-273-8600
PO Box 25046, Federal Center    cranswick@........
Denver, CO 80225-0046  USA      E.M. Forster said, "Only connect".




_____________________________________________________________________

Public Seismic Network Mailing List (PSN-L)


From: Edward Cranswick 
Subject: test: PSN-L@..............
Date: Sun, 02 Aug 1998 18:30:28 -0600

PSN-L@..............

--
Edward Cranswick                Tel: 303-273-8609
US Geological Survey, MS 966    Fax: 303-273-8600
PO Box 25046, Federal Center    cranswick@........
Denver, CO 80225-0046  USA      E.M. Forster said, "Only connect".




_____________________________________________________________________

Public Seismic Network Mailing List (PSN-L)


From: meredith lamb 
Subject: Re: PSN Acknowledged
Date: Mon, 03 Aug 1998 16:00:31 -0600



Edward Cranswick wrote:

> Larry-
>     The article is available at
> 
> Interestingly enough, some of the references in it to earthquake prediction,
> China and monitoring seismicity using public participation sound similar to
> John Lahr's USGS Open-file report of 1978 and the AGU poster that Robert
> Banfill and I presented in 1990.  Thanks to Charles Watson for pointing out
> the reference.
> -Edward
>

Hello Edward,

Indeed it looks like you were busy on the weekend, as you were
the only email traffic on Sunday.

In reference to the above...is there any access to John Lahr's open
file report of 1978?  Of course, if its no longer accessible; the
general message is likely the same I assume.

I commend your never ending efforts to encourage more participation
from the public as a whole.  Earthquakes are of course, not a very
positive subject of interest, as they are dealt with by the media in
terms of death and misery.  This approach often overshadows other
preventative presentations of life and property, which often does not
have the right amount of market share or sales appeal.

As far as prediction efforts, the only point I would care to comment
about, is that the general idea of prediction, should be pinpointed to within
a day of the event...which is a preposterious notion, on the geologic scale of
time.  I would think a plus or minus 5 years would be more of a
bulls eye on a successful prediction, and even here, a additional
century or two leeway, could fall in the success circle zone.  Geological
realism controlls the event, not human timescales.   Parkview and other
sites really deserve a much larger time frame of caution.
............

On a recent TV show, it looks like they are going for the use of
automotive accelerometers in the Los Angeles area...or at least
implied strong interest for their use, as a more distant early warning
system between P & S waves..  Is this approach still in progress,
or is the show out of date?  I believe if my memory serves me right,
that a USGS employee, a Dr. Evans was engaged in this project?

Thanks, Meredith Lamb







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Public Seismic Network Mailing List (PSN-L)


From: meredith lamb 
Subject: Big quake coming in
Date: Tue, 04 Aug 1998 13:55:53 -0600

Hi guys,

See my computer SDR is literally being smeared by a big quake
"somewhere".  Can't even easily follow individual traces.

Hope it is not a killer of people and property.

Meredith Lamb


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Public Seismic Network Mailing List (PSN-L)


From: Marchal van Lare 
Subject: Re: Big quake coming in
Date: Tue, 4 Aug 1998 16:37:01 -0400

Hi all,

This is the first raw data: =


04Aug1998 18:59:07.8  2.6S  81.8W 10 mb=3D6.5 A SED NEAR COAST ECUADOR   =
     1918

source:
http://seismo.ethz.ch/redpuma/redpuma_ami_list.html

Regards,

Marchal van Lare
Nieuwvliet, The Netherlands
 =

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From: meredith lamb 
Subject: Near coast of Ecuador
Date: Tue, 04 Aug 1998 15:06:34 -0600

NEIC says;

98/08/04 18:59:19 Lat 0.47s Long 80.05w  Depth 33.0
Mag 7.1Ms  Near coast of Ecuador

Meredith Lamb




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From: "Walt Williams" 
Subject: PSN-L: Geophone Mounting
Date: Tue, 4 Aug 1998 14:38:49 +0000

Hello All,

I have been experimenting with geophones. 

How are geophones to the connected to amplifier? 

Should the geophone be soldered directly to a an amplifier PCB made 
for that purpose?

Or should the geophone be connected through some short cable/wires to 
the amplifier? 

Thanks in advance.

Walt Williams, 98.08.04
dfheli@..............

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Public Seismic Network Mailing List (PSN-L)


From: "Frank Cooper" 
Subject: Re: Big quake coming in
Date: Tue, 4 Aug 1998 16:58:04 -0500



Hi PSN,
I would like to congratulate John Cole (W5AUH) of Pearland, Texas, USA,
upon receiving his first big earthquake (i.e. 7.1 NEAR COAST OF EQUADOR)
via his newly constructed Lehman seismograph. John called me earlier this
afternoon and asked me if I was receiving something big on my Lehman.  Sure
enough, the pen recorder was hitting the stops on both sides and the signal
was saturating my computer.  The pen on Johns' Esterline-Angus chart
recorder was also hitting the stops on both sides.  We then went on fast
scan amateur television and compared our chart recordings in progress
visually while hopefully many people in the Houston area were watching our
TV broadcast.  My amateur call is W5VID.  We were transmitting on 1.2ghz
and receiving on 70cm (cable channel 57 reception by using an external
antenna) through the Houston Amateur Television Society (HATS) repeater in
downtown Houston, Texas. Several times during the past year and a half I
have broadcast live television pictures of seismograms of an earthquake in
progress.  This may be a first for two live television broadcasts comparing
seismograms of an earthquake in progress.

John has discovered a simple way to dramatically increase the period of a
Lehman.  John will share his discovery on my web site
(http://freeweb.pdq.net/fxc/) with pictures and text within the next day or
two.

Frank Cooper, Friendswood, Texas, USA


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From: "Francesco" 
Subject: BIG QUAKE -    
Date: Wed, 5 Aug 1998 00:55:24 +0200

LARGE P
S in saturation
longe LQ, LR  e T

MS > 7.2

I.E.S.N.  PSN ITALY
Francesco Nucera









LARGE P


S in saturation


longe LQ, LR  e T


 


MS > 7.2


 


I.E.S.N.  PSN =
ITALY


Francesco =
Nucera


From: S-T Morrissey 
Subject: bimetallic thermometer
Date: Tue, 4 Aug 1998 19:57:35 -0500 (CDT)

Barry,

I think that mounting the center of the bimetallic spiral at 
the hinge would probably result in less noise from the 
mechanical arrangement, but would reduce the effect of the 
thermometer, as you observe.  I have the spiral end attached 
to the boom, and the free end applying the correcting force 
to the center boom suppport. I thought of reversing the arrangement,
with the free end contacting the boom near the feedback coil, 
but the bimetallic element is ferrous and is attracted by the 
main magnet. I can reverse the direction, which will allow the
spiral to be mounted to the boom support with a more definitive
method of adjusting the effect (by rotating the center of it).

An easy way to observe the effect of the thermometer is to 
monitor the displacement transducer output and shine a penlight
flashlight (Mini-maglight) on the bimetallic spiral. The heat
of the light will drive the boom up (and off scale) in a few
seconds. A large flashlight will similarly warm the main spring.

The transducer output that you have is a realistic number, but
the transfer function needs the 10x value for the feedback to 
be stable. I do not have any problems with voltage limitations
in normal operation with r= 400 000 volts/meter. The usual
microseismic background runs about 2 to 5 millivolts at the 
VBB output. Todays Mb 7.1 ECUADOR quake peaked at 180 millivolts.
I have the diurnal thermal wander down to about +- 1 volt.
When the feedback is on, the mass movement is reduced by
about 20 to 1 with the Beta instrument.

Regards,
Sean-Thomas

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From: S-T Morrissey 
Subject: geophone info list
Date: Tue, 4 Aug 1998 20:04:39 -0500 (CDT)

I have a flyer here from GEOSWISS GEOPHONE DATA BANK that
proposes a geophone data bank with data on over 3 000
geophones. It is set up for Windows 3.1, 95.
It says it has data, specifications, responses, plots,
etc. at:

http://menbers.aol.com/geophones/geo3.htm

or Geophones@.......

I have not looked at it yet; maybe someone can evaluate it.

Regards,
Sean-Thomas

_____________________________________________________________________

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From: Edward Cranswick 
Subject: Did Clinton feel the Earth move?
Date: Tue, 04 Aug 1998 22:15:52 -0600

Bob-
     Last Thursday (30 July), when I talked to the USGS Education &
Outreach representatives about the PSN, in response to a question about
what kind of ground motions would be felt in Washington DC from
seismicity in Eastern North America, I showed them your record from
Virginia of the earthquake that happened that day in Quebec.
-Edward

Bob Laney wrote:
>
>     ---------------------------------------------------------------
>
>                    Name: 980730a.rl2
>     Part 1.2       Type: unspecified type (application/octet-stream)
>                Encoding: base64


--
Edward Cranswick                Tel: 303-273-8609
US Geological Survey, MS 966    Fax: 303-273-8600
PO Box 25046, Federal Center    cranswick@........
Denver, CO 80225-0046  USA      E.M. Forster said, "Only connect".




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From: "Al Allworth" 
Subject: RE: geophone info list
Date: Tue, 4 Aug 1998 23:02:58 -0700

I couldn't get the geophone data list to on AOL to work. The "user"
subaddress
jumps into another url. They must have changed things around. I tried a
search
with no luck.			Al

> -----Original Message-----
> From: S-T Morrissey [mailto:sean@............
> Sent: Tuesday, August 04, 1998 6:05 PM
> To: psn-l@.............
> Subject: geophone info list
>
>
> I have a flyer here from GEOSWISS GEOPHONE DATA BANK that
> proposes a geophone data bank with data on over 3 000
> geophones. It is set up for Windows 3.1, 95.
> It says it has data, specifications, responses, plots,
> etc. at:
>
> http://menbers.aol.com/geophones/geo3.htm
>
> or Geophones@.......
>
> I have not looked at it yet; maybe someone can evaluate it.
>
> Regards,
> Sean-Thomas
>
> _____________________________________________________________________
>
> Public Seismic Network Mailing List (PSN-L)
>
> To leave this list email listserver@............. with the body of the
> message: leave PSN-L
>


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From: Larry Cochrane 
Subject: Re: PSN-L: Geophone Mounting
Date: Wed, 05 Aug 1998 00:02:39 -0700

At 02:38 PM 8/4/98 +0000, Walt wrote:
>Hello All,
>
>I have been experimenting with geophones. 
>
>How are geophones to the connected to amplifier? 
>
>Should the geophone be soldered directly to a an amplifier PCB made 
>for that purpose?
>
>Or should the geophone be connected through some short cable/wires to 
>the amplifier? 

Geophones are usually pretty low impedance (resistance) so you will not
have a problem running a few feet of shielded wire between the sensor and
the amp.

-Larry Cochrane
Redwood City, PSN


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From: "Walt Williams" 
Subject: PSN-L: RE: geophone info list
Date: Wed, 5 Aug 1998 03:41:40 +0000

Hello ST, and All,

The posted URL has a mispelling: 

http://menbers.aol.com/geophones/geo3.htm

the corrected URL:

http://members.aol.com/geophones/geophones.html

homepage:

http://members.aol.com/geophones/geophones.html

Upon visiting the site: the topic appears to be demonstration
software (available for download) which displays information about
geophones from a database. The program allows dynamic modelling of
strings/arrays of geophones. The download version of the database
appears truncated. 

Walt Williams, 98.08.05
dfheli@..............
========================================================



------- Forwarded Message Follows -------
From:          "Al Allworth" 
To:            "PSN-L Mailing List" 
Subject:       RE: geophone info list
Date:          Tue, 4 Aug 1998 23:02:58 -0700
Reply-to:      PSN-L Mailing List 

I couldn't get the geophone data list to on AOL to work. The "user"
subaddress jumps into another url. They must have changed things
around. I tried a search with no luck.			Al

> -----Original Message-----
> From: S-T Morrissey [mailto:sean@............
> Sent: Tuesday, August 04, 1998 6:05 PM
> To: psn-l@.............
> Subject: geophone info list
>
>
> I have a flyer here from GEOSWISS GEOPHONE DATA BANK that
> proposes a geophone data bank with data on over 3 000
> geophones. It is set up for Windows 3.1, 95.
> It says it has data, specifications, responses, plots,
> etc. at:
>
> http://menbers.aol.com/geophones/geo3.htm
>
> or Geophones@.......
>
> I have not looked at it yet; maybe someone can evaluate it.
>
> Regards,
> Sean-Thomas
>
> _____________________________________________________________________
>
> Public Seismic Network Mailing List (PSN-L)
>
> To leave this list email listserver@............. with the body of the
> message: leave PSN-L
>


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From: Arie Verveer 
Subject: Amateur PSN
Date: Wed, 05 Aug 1998 21:39:41 +0800

Hi

Here is one that warms the heart.

For the last 4 months the federal  Governments, local  Geophysical Observatory
(Western Australia) has been sending me a list of  the local, low level seismic events.
This has help immeasurably in identifying the small local events in the data record. So I
responded by sending them the printouts. I then started to wonder if this  might  be
seen as an "amateur irritant",  so I contacted the people involved and asked the
question "Do you really want this stuff". There answer was yes.
So there is a small place for the amateur in the local events. That warms the heart.

Arie.


Then again they may need the printouts to line the bottom of the "parrots" cage. ?



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From: Edward Cranswick 
Subject: Re: Amateur PSN
Date: Wed, 05 Aug 1998 11:58:03 -0600

Arie-
    One of these days maybe the USGS will want some data from the PSN. Just after and because
of the PSN AGU presentation last December, I did get a request for PSN records of local
events in the San Francisco Bay Area from a seismologist from University of California
Berkeley, but at the time I was not able to to find suffiicient unclipped data from
well-behaved instruments.
    On the other hand, as they say in California (or as some said back in the 1960's): "Every
day in every way, better and better".
-Edward

Arie Verveer wrote:

> Hi
>
> Here is one that warms the heart.
>
> For the last 4 months the federal  Governments, local  Geophysical Observatory
> (Western Australia) has been sending me a list of  the local, low level seismic events.
> This has help immeasurably in identifying the small local events in the data record. So I
> responded by sending them the printouts. I then started to wonder if this  might  be
> seen as an "amateur irritant",  so I contacted the people involved and asked the
> question "Do you really want this stuff". There answer was yes.
> So there is a small place for the amateur in the local events. That warms the heart.
>
> Arie.
>
> Then again they may need the printouts to line the bottom of the "parrots" cage. ?
>
> _____________________________________________________________________
>
> Public Seismic Network Mailing List (PSN-L)
>
> To leave this list email listserver@............. with the body of the
> message: leave PSN-L



--
Edward Cranswick                Tel: 303-273-8609
US Geological Survey, MS 966    Fax: 303-273-8600
PO Box 25046, Federal Center    cranswick@........
Denver, CO 80225-0046  USA      E.M. Forster said, "Only connect".




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From: 
Subject: Re: Did Clinton feel the Earth move?
Date: Wed, 5 Aug 1998 16:54:17 EDT

Edward--

Interesting!  Glad my record of the Quebec event was of use.  Now, if the one
yesterday in Ecuador had been available for your discussions--it was a dandy.

Bob

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From: "Frank Cooper" 
Subject: simple way to increase the period of a Lehman
Date: Wed, 5 Aug 1998 22:01:42 -0500


Hi,
I have posted pictures and text on my home page illustrating John Cole's
(W5AUH) simple way to increase the period of a Lehman.  There may be slight
changes in the text during the next day or two.
Frank Cooper (W5VID), 
Friendswood, Texas, USA


> John has discovered a simple way to dramatically increase the period of a
> Lehman.  John will share his discovery on my web site
> (http://freeweb.pdq.net/fxc/) with pictures and text within the next day
or
> two.
> 
> Frank Cooper, Friendswood, Texas, USA



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From: bob ogburn 
Subject: EW activity for 40 Min.
Date: Wed, 05 Aug 1998 20:13:53 -0700

About 40 min. ago, strong East-West motion here. Still moving.



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From: Gregory Bajuk 
Subject: 16 bit Audio A/D cards
Date: Wed, 5 Aug 1998 21:34:13 -0700 (PDT)

Since most computer audio cards can convert music/voice/sound input to a
digital .wave file, can these cards be used to record and display
seismograph files as well.  Has anyone tried this? If so please reply with
your experiences.  Thanks.
Greg Bajuk


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Public Seismic Network Mailing List (PSN-L)


From: Greg 
Subject: Re: 16 bit Audio A/D cards
Date: Wed, 05 Aug 1998 22:24:20 -0700

Gregory Bajuk wrote:

> seismograph files as well.  Has anyone tried this? If so 

I was very disappointed to see this message, but since it's out there...
I wanted to see how far I could get with it and announce it to the list
if it was a major breakthrough or something.

I just tried this today. I have often thought of it since I first saw
the cost of DA cards. I have a geophone connected to the line in on my
sound card right now. I was playing around with jumping up and down and
beating the floor with my fist and I finally noticed the gain on the
line in was set to half. I have a gif file with about six signals from
me pounding my heal on the carpet. It doesn't look too bad until you
consider that I was about 2 feet away and I had to amplify the signal
the equivalent of 14 times the original. I'm going to try the microphone
again soon.

One of the main things I wanted to do on the internet tonight was look
into writing or finding software for it. I've been playing with some
software called HamView lately and I managed to see some signals in that
also. It's very neat software, if there are any hams on the list. I can
see all kinds of noise and satellites and ... There's a similar program
that requires registration and doesn't seem to show as much called
FFTDSP4.2 or something similar.

If I can't find the software I'd like to find some C function that
allows you to retrieve the signal from either input source on the sound
card. One thing to consider is that I think the voltage range for the
line in is +- 2V? I think the Larry C. board is +- 5V? It might need a
different preamp than the Larry C. because of the voltage difference,
but I'm not an electronics wiz.

,Greg

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From: David Josephson 
Subject: Re: 16 bit Audio A/D cards
Date: Wed, 5 Aug 1998 23:29:28 -0700 (PDT)

Most of the computer sound cards roll off below a few tens of
Hz. They use delta-sigma analog to digital converters that are
fine for audio, but don't give very good performance in the 
0.01 - 10 Hz range you need.

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From: Steve Hammond 
Subject: [Fwd: LAte late PSN additions]
Date: Wed, 05 Aug 1998 22:56:53 -0700

RPC is Dick Chelberg
BK1 is Bruce Kinney
GC1 is Jan Froom

I mist have not saved the data at some point because I did add them at
one point. 
Thanks for bringing it to my attention.

Regards, Steve Hammond
Steve An error was just brought to my attention. I missed three of the
main PSN stations in the survey... can you add them?
Thanks-- Steve Hammond

RPC 37.24 -121.845 OB1 PSN
BK1 37.24 -121.839 OB1 PSN
GC1 37.5 -126.1 OB2 PSN

From: "David A. Nelson" 
Subject: Re: EW activity for 40 Min.
Date: Thu, 06 Aug 1998 19:48:58 +1200

At 08:13 PM 8/5/98 -0700, you wrote:
>About 40 min. ago, strong East-West motion here. Still moving.

bob  where are u   ??

 what was the universal time (UTC)  ??


cheers 
dave

Co-ordinator:
New Zealand
Public Seismic Network
			Dave A. Nelson   ZL4TBN
			24 Jensen St.,   
			Green Is., Dunedin,  
			South Is.. New Zealand.  

http://psn.quake.net/dave/home.htm   

IF there indeed are other parallel universes... I can now rest in the
knowledge, that in at least one of them, I am filthy rich and drive a red
Ferrari


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From: Edward Cranswick 
Subject: Re: Near coast of Ecuador
Date: Thu, 06 Aug 1998 03:05:48 -0600

Meredith-
    Though I have not yet responded to your previous message, I wanted to
look at some of your vector (three-component) records of the Ecuador event
before they became too stale.

    ftp://groundmotion.cr.usgs.gov/PSN/lamb/980804/VEC18V.GIF
is 18 minutes of the three components of velocity as recorded and plotted
to the same amplitude scale.
    1 000/000  =  Z
    2 090/000  =  N
    3 090/090  =  E
    [There are two spherical-coordinate values in degrees, separated by a
'/',
    that define the direction of positive ground motion of each orthogonal

    component. The first value is the zenith angle, i.e., the inclination
measured
    from the zenith, i.e., 000/ = vertical-up, and 090/ = horizontal.
    The second value is the azimuth measured clockwise from North,
    i.e., /000 = North, and /090 = East]
Note that the P phase is somewhat larger on the vertical component (Z)
than on the horizontal components (N, E) and that the S and SS&SSS phases
are much larger on the horizontals than on the vertical.  Also note that
the amplitudes of corresponding P and S phases on both horizontals are
roughly equal.

    ftp://groundmotion.cr.usgs.gov/PSN/lamb/980804/VEC18VR.GIF
is the same as the previous plot (the amplitude scale has been changed by
about 15%) except that the N and E horizontal components have been rotated
respectively into the radial (R) and tangential (T) orientations with
respect to the direction at the receiver (station) of waves propagating
away from the source (epicenter). This radial direction away from the
source as measured at the receiver is the opposite (+/-180 degrees) of the
"Station to Event Azimuth: 144.1 degrees" calculated by WinQuake 2.5.2 for
this station/earthquake pair. Hence:
    1 000/000  =  Z
    2 090/324  =  R
    3 090/054  =  T
Note that the different phases have now been differentially partitioned
between the horizontal components. The P phases are virtually absent on
the T component (as they should be in theory), and nearly all of the
P-wave energy is on the R component. The S phase appears to be different
on the R & T components, and the SS&SSS phases are strong on T but weak on
R.

    I have done more analysis of this vector record and hope to put some
more of it out on the Web.
-Edward

meredith lamb wrote:

> NEIC says;
>
> 98/08/04 18:59:19 Lat 0.47s Long 80.05w  Depth 33.0
> Mag 7.1Ms  Near coast of Ecuador
>
> Meredith Lamb
>
> _____________________________________________________________________
>
> Public Seismic Network Mailing List (PSN-L)
>
> To leave this list email listserver@............. with the body of the
> message: leave PSN-L



--
Edward Cranswick                Tel: 303-273-8609
US Geological Survey, MS 966    Fax: 303-273-8600
PO Box 25046, Federal Center    cranswick@........
Denver, CO 80225-0046  USA      E.M. Forster said, "Only connect".




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From: robert barns <75612.2635@..............>
Subject: EW activity for 40 Min.
Date: Thu, 6 Aug 1998 09:45:31 -0400

Where is "here" ?
Bob Barns

Quantum Mechanics--The dreams stuff is made of.

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From: Steve Hammond 
Subject: Re: EW activity for 40 Min.
Date: Thu, 06 Aug 1998 06:56:17 -0700

Bob lives in the San Francisco Bay area.

robert barns wrote:
> 
> Where is "here" ?
> Bob Barns
> 
> Quantum Mechanics--The dreams stuff is made of.
> 
> _____________________________________________________________________
> 
> Public Seismic Network Mailing List (PSN-L)
> 
> To leave this list email listserver@............. with the body of the
> message: leave PSN-L

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From: Greg 
Subject: Re: 16 bit Audio A/D cards
Date: Thu, 06 Aug 1998 09:53:57 -0700

David Josephson wrote:

> 0.01 - 10 Hz range you need.

When you consider that the geophone is a 10 Hz geophone and it's an
almost free setup, I still think it's worth pursuing.

I've been reading about the hardware level programming and it would
appear so far to be restricted to recording at a minimum of 4-5 KHz. I'm
going to check some more and it might be easy to just strip out most of
the data as it's recorded to disk. If not the disk would have to be
pretty darn big.

,Greg

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From: meredith lamb 
Subject: Vector Analysis of ML Sprengnether S5000 set
Date: Thu, 06 Aug 1998 11:56:17 -0600

Hi Edward,

Thanks for your time and effort of the analysis of 8/6/98.  I'll be
looking forward to seeing the afore mentioned upcoming additional
data in the future.

Am assuming that the current part only shows the difference in
horizontals response, and outside of variables like damping and
amplifier differences there may not be much more, that can be
done to attain a more equitable response.

Outside of the generious time for the above:

I would also be very interested in your accessment of the the normal
N-S (ML2), versus, the ML4 experimental Hall sensor phase/frequency
responses, which is on the same boom of the ML2, Ecuador quake dated
8/4/98.

The time that Robert Lamb and I have put into the sensor has been
substantial, and it currently is of very strong interest, for possible
ongoing continuing improvement.  Eventually I hope to throw on these
sensors on all 3 components, for comparisons of the Hall v/s the
normal velocity coils.  Would appreciate even a very rough appraisal
as I lack everything compared to your experience/equipment.  I do have
the unprocessed files if you are that interested, which I can forward
via email or regular mail. To say the least; I think they have alot
of potential for seismic use or even velocity coil sensor replacement,
but that is just my opinion.  Any eventual results will be public use
or disclosure of course.  Am also assuming this is not new stuff, but,
I've heard or seen zero on Hall sensor seismic use, outside of
Albert Judge of England. 

Thanks, Meredith Lamb


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From: "Steve Carniglia" 
Subject: Re: 16 bit Audio A/D cards
Date: Thu, 6 Aug 1998 11:14:57 -0700

Yes...........quite a bit of fooling around with this and yes it works but
getting the data to conform to the standard is a REAL challenge......there
is a bunch of free software on the internet that will allow you to watch the
data.....

Best Regards
Steve



-----Original Message-----
From: Gregory Bajuk 
To: PSN-L@............. 
Date: Wednesday, August 05, 1998 9:37 PM
Subject: 16 bit Audio A/D cards


>Since most computer audio cards can convert music/voice/sound input to a
>digital .wave file, can these cards be used to record and display
>seismograph files as well.  Has anyone tried this? If so please reply with
>your experiences.  Thanks.
>Greg Bajuk
>
>
>_____________________________________________________________________
>
>Public Seismic Network Mailing List (PSN-L)
>
>To leave this list email listserver@............. with the body of the
>message: leave PSN-L


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From: "Steve Carniglia" 
Subject: Re: 16 bit Audio A/D cards
Date: Thu, 6 Aug 1998 11:16:56 -0700

Yes there is lots of this stuff out there.....I have experimented with a
bunch of it....

Best Regards  or as we say in the ham world, 73

Steve   KV6A




-----Original Message-----
From: Greg 
To: PSN-L Mailing List 
Date: Wednesday, August 05, 1998 10:30 PM
Subject: Re: 16 bit Audio A/D cards


>Gregory Bajuk wrote:
>
>> seismograph files as well.  Has anyone tried this? If so
>
>I was very disappointed to see this message, but since it's out there...
>I wanted to see how far I could get with it and announce it to the list
>if it was a major breakthrough or something.
>
>I just tried this today. I have often thought of it since I first saw
>the cost of DA cards. I have a geophone connected to the line in on my
>sound card right now. I was playing around with jumping up and down and
>beating the floor with my fist and I finally noticed the gain on the
>line in was set to half. I have a gif file with about six signals from
>me pounding my heal on the carpet. It doesn't look too bad until you
>consider that I was about 2 feet away and I had to amplify the signal
>the equivalent of 14 times the original. I'm going to try the microphone
>again soon.
>
>One of the main things I wanted to do on the internet tonight was look
>into writing or finding software for it. I've been playing with some
>software called HamView lately and I managed to see some signals in that
>also. It's very neat software, if there are any hams on the list. I can
>see all kinds of noise and satellites and ... There's a similar program
>that requires registration and doesn't seem to show as much called
>FFTDSP4.2 or something similar.
>
>If I can't find the software I'd like to find some C function that
>allows you to retrieve the signal from either input source on the sound
>card. One thing to consider is that I think the voltage range for the
>line in is +- 2V? I think the Larry C. board is +- 5V? It might need a
>different preamp than the Larry C. because of the voltage difference,
>but I'm not an electronics wiz.
>
>,Greg
>
>_____________________________________________________________________
>
>Public Seismic Network Mailing List (PSN-L)
>
>To leave this list email listserver@............. with the body of the
>message: leave PSN-L


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From: "James M Hannon" 
Subject: Re: 16 bit Audio A/D cards
Date: Thu, 6 Aug 1998 13:15:21 -0500






Greg  on 08/06/98 11:53:57 AM

Please respond to PSN-L Mailing List 

To:   PSN-L Mailing List 
cc:
Subject:  Re: 16 bit Audio A/D cards




I've been reading about the hardware level programming and it would
appear so far to be restricted to recording at a minimum of 4-5 KHz. I'm
going to check some more and it might be easy to just strip out most of
the data as it's recorded to disk. If not the disk would have to be
pretty darn big.

,Greg



Greg,

I did a little looking and it appears that you are limited to 4KHz minimum
      sample rate by the hardware.  It would be easy enough to throw away
      samples and only keep every Nth sample. This will work fine as long
      as you have some external anti aliasing filter in your setup.

I have been considering using the sound card in a laptop to record geophone
      outputs to do a little seismic exploration with geophones and a large
      hammer. Haven't found the time to persue it though. :)



Jim Hannon




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Public Seismic Network Mailing List (PSN-L)


From: "James M Hannon" 
Subject: Re: Near coast of Ecuador
Date: Thu, 6 Aug 1998 13:18:42 -0500

Edward,
Thanks for showing us your analysis of the 3 axis data.  I had been
wondering what sort of usefull information could be extracted if you had 3
axis data avaliable.  This will be very usefull when I get my three axis
instrument running.

Jim Hannon



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From: Pinpoint 
Subject: Re: 16 bit Audio A/D cards
Date: Thu, 06 Aug 1998 11:51:34 -0700

At 11:16 AM 8/6/98 -0700, Steve Carniglia wrote:
>Yes there is lots of this stuff out there.....I have experimented with a
>bunch of it....
>
>Best Regards  or as we say in the ham world, 73

Perhaps I am misreading what this thread is all about.
  We use graphics to demonstrate trends in a way that many people can
understand. In that same sense if we were able to 'hear' the trace besides
just seeing it, what an interesting thing that might be for some.
  If it were a simple cut and paste from the trace onto something such as
Soundblaster or Goldwave....but none of those manufactures allow for
graphics to digital. What about raw data? Would be very easy to convert raw
data into sound .wav files
.. I have done something similar to that in the past, but knew about the
media with which I was working. If someone would be willing to send me a
raw data file with simple explanation and trace gif, I would be willing to
write a conversion program to SB/GUS digital standards...
Bob

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From: lahr@..................
Subject: All Electronics Corp. Geophones
Date: Thu, 6 Aug 1998 13:12:07 -0600 (MDT)

This is from the back page of the All Electronics Corp. 
catalog #496, which is the one available in PDF format on
the web.

JCLahr

INTERNET USERS!
Visit Our WWW Site
http://www.allcorp.com
E-Mail us at
allcorp@...........
California Store Locations
905 S. Vermont Avenue
Los Angeles, 90006
(213) 380-8000
14928 Oxnard Street
Van Nuys, 91411
(818) 997-1806
BULK RATE
US POSTAGE
PAID
ONTARIO, CA
PERMIT # 12
A AL LL L
E EL LE EC CT T R R O ON NI I C CS S
C O R P O R AT I O N

GEOPHONE -
VIBRATION SENSOR
Extremely sensitive to all kinds of
vibration, from a tiny tap on a table to
a truck driving by in the street. These
Geophones were used in oil exploration to
gather geological statistics. They can be used as
seismic detectors or shock detectors in alarm systems.
Inside is a magnet suspended in a coil which
generates an electrical current capable of lighting an
LED. Natural frequency: 10Hz. We supply a couple
of simple circuit diagrams which allow you to monitor
and harness the Geophone's response. 1.6" high x
1.2" diameter. These are
functioning used units.
CAT # GP-1

> From: Woolf Kanter 
> Subject: Re: Geophone on sale
> 
> Meredith,
> 
> The geophones are made by Geosource Inc., Model # MD-81.  They were
> manufactured in 1985 and appear to have been used.  They measure 616 ohms
> across the coil.
> Guaranteed functional.  That's all we know.
> 
> All Electronics Corp
> 

Actually the coil is suspended in the field of a magnet.

JCLahr

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From: "James M Hannon" 
Subject: Re: 16 bit Audio A/D cards
Date: Thu, 6 Aug 1998 14:15:51 -0500






Pinpoint  on 08/06/98 01:51:34 PM

Please respond to PSN-L Mailing List 

To:   PSN-L Mailing List 
cc:
Subject:  Re: 16 bit Audio A/D cards




Perhaps I am misreading what this thread is all about.
  We use graphics to demonstrate trends in a way that many people can
understand. In that same sense if we were able to 'hear' the trace besides
just seeing it, what an interesting thing that might be for some.
  If it were a simple cut and paste from the trace onto something such as
Soundblaster or Goldwave....but none of those manufactures allow for
graphics to digital. What about raw data? Would be very easy to convert raw
data into sound .wav files
.. I have done something similar to that in the past, but knew about the
media with which I was working. If someone would be willing to send me a
raw data file with simple explanation and trace gif, I would be willing to
write a conversion program to SB/GUS digital standards...
Bob

Bob,
The thread is about recording the output of either geophones or a
seismograph with a sound card rather than listening to the recorded data.

Listening to a data file is fairly easy. I have converted one of Larry's
recordings into a .au file and put it on the web at
http://soli.inav.net/~jmhannon/seismology.html click on "listen to an
earthquake" if you have a browser set up to play .au files.


Jim Hannon




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From: "Phil Giannini" 
Subject: Earthquake Lists
Date: 6 Aug 1998 13:08:03 -0800

Mail*Link(r) SMTP               Earthquake Lists


Hello Fellow Enthusiasts,
    Not too very long ago there was a great website that had a complete
archive listing of past earthquakes. It was designed in a calendar-like
format where you could click on a date and get a listing of all the more
significant quakes for that particular day. The location was:
   http://www.cdidc.org:65120/web-bin/bulldaily/calendar=yes/bulletin=GAMMAs

   I get a "no such URL" message when I try that location now. My question is,
does anyone know what happened to that website and is there something
similar to that around anymore. Any input will be appreciated.

                                        Thanks, Phil  SFN&Z



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From: S-T Morrissey 
Subject: VCO into sound card
Date: Thu, 6 Aug 1998 15:20:52 -0500 (CDT)

Re. Sound cards

For input to a PC sound card, we have considered the possibility 
of using a VCO (voltage controlled oscillator) IC after the 
seismometer pre-amp to convert the seismic signal into an FM audio 
tone whose frequency change is proportional to the input voltage. 
We use this FM-VCO method in all the analogue telemetry that we do, 
since it allows us to transmit the near DC seismic signal over VHF 
radio links and standard telephone lines. With 10 VCO center frequencies, 
each deviating +- 125 hz for a +- 2 volt input, we can get ten 
seismic stations on one RF link or phone line.
(for reference, we use a preamp gain of 72db, or x 4 000, on the
output of an L4-C seismometer with a 5500 ohm coil at 270 V/M/sec.)

This audio VCO would get the seismic input into the passband of 
the sound card. THere is software that can read the instantaneous 
frequency value, which would have to be sampled at some moderate 
rate and written to a buffer. To recover the seismic signal, a 
digital "discriminator" would compare the instantaneous FM frequency 
with the VCO referenced center frequency, the difference being the
seismic voltage in volts/hz, which is 16 mv/hz with our VCOs.
With oversampling, the difference could be determined with a phase
resolution of 45 degrees or better, which, with a +- 125 hz deviation, 
would allow a dynamic range of 1000 or 60 db, or about 10 bits of
resolution. Of course, the VCO span could be increased by a factor of
10 or more, like 2 khz +- 1250 hz, to get a dynamic range of 
10 000, or 80 db, or 13 to 14 bits.

With the dynamic range needed for seismometer data, 10 bits is
not really enough; our lowest resolution for network data is 16 bits
and the broadband stations have 24 bit ADCs.

Regards,
Sean-THomas


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From: Canie Brooks 
Subject: Re: Earthquake Lists
Date: Thu, 06 Aug 1998 13:18:41 -0700

Try this:
http://www.cmr.gov/web-bin/recentevents

canie

At 01:08 PM 8/6/98 -0800, Phil Giannini wrote:
>Mail*Link(r) SMTP               Earthquake Lists
>
>
>Hello Fellow Enthusiasts,
>    Not too very long ago there was a great website that had a complete
>archive listing of past earthquakes. It was designed in a calendar-like
>format where you could click on a date and get a listing of all the more
>significant quakes for that particular day. The location was:
>   http://www.cdidc.org:65120/web-bin/bulldaily/calendar=yes/bulletin=GAMMAs
>
>   I get a "no such URL" message when I try that location now. My question
is,
>does anyone know what happened to that website and is there something
>similar to that around anymore. Any input will be appreciated.
>
>                                        Thanks, Phil  SFN&Z
>
>
>
>_____________________________________________________________________
>
>Public Seismic Network Mailing List (PSN-L)
>
>To leave this list email listserver@............. with the body of the 
>message: leave PSN-L
> 

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From: Pinpoint 
Subject: Re: 16 bit Audio A/D cards
Date: Thu, 06 Aug 1998 13:29:05 -0700

At 02:15 PM 8/6/98 -0500, James M Hannon wrote:

>Bob,
>The thread is about recording the output of either geophones or a
>seismograph with a sound card rather than listening to the recorded data.
>
>Listening to a data file is fairly easy. I have converted one of Larry's
>recordings into a .au file and put it on the web at
>http://soli.inav.net/~jmhannon/seismology.html click on "listen to an
>earthquake" if you have a browser set up to play .au files.


Jim and others;
  Thanks so much for clarifying! So...What method are you or others using
to 'hear' the earthquake? Would some of you who know or have this software
please share other earthquake sounds. I believe I may have had an intuitive
thought on this sounds at PSN which you directed me to.
  In OW...anyone with EQ sounds, please send them to me as attachments. I
noticed the .au file was not very long so attachments should not be a
problem in either direction...
  FYI Netscape is set-up to hear .au sounds as long as one has a sound card
and knows how to configure NS.
Bob


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From: David Josephson 
Subject: Re: VCO into sound card
Date: Thu, 6 Aug 1998 14:25:31 -0700 (PDT)

Sean-Thomas writes

> For input to a PC sound card, we have considered the possibility 
> of using a VCO (voltage controlled oscillator) IC after the 
> seismometer pre-amp to convert the seismic signal into an FM audio 
> tone whose frequency change is proportional to the input voltage. 
> We use this FM-VCO method in all the analogue telemetry that we do, 

This makes good sense to me. It would also be a way to get many 
seismic signals into a cheap computer at once. For example, several
axes of geophones, and one or more long period instruments (perhaps
with different deviation limits according to the s/n required). Then
it would not be difficult to expand the software mentioned:

> the sound card. THere is software that can read the instantaneous 
> frequency value, which would have to be sampled at some moderate 
> rate and written to a buffer. To recover the seismic signal, a 

The limitations on s/n mentioned

> would allow a dynamic range of 1000 or 60 db, or about 10 bits of
> resolution. Of course, the VCO span could be increased by a factor of
> 10 or more, like 2 khz +- 1250 hz, to get a dynamic range of 
> 10 000, or 80 db, or 13 to 14 bits.

can be further expanded, as a typical sound card will record at
44.1 kHz stereo, which is about 40 kHz of bandwidth (20-20kHz,
times two channels)

While the sampling rate would be high, the software could reduce
this to baseband at the desired data rate before sending it to disk.


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From: Arie Verveer 
Subject: Re: Earthquake Lists
Date: Fri, 07 Aug 1998 00:29:22 +0800

Hi Phil

I know what you mean, I used the list often. So armed with
bull dogged determination, it was tracked down to :

http://www.pidc.org/dataprodbox/prod.html

Regards

Arie


Phil Giannini wrote:

> Mail*Link(r) SMTP               Earthquake Lists
>
> Hello Fellow Enthusiasts,
>     Not too very long ago there was a great website that had a complete
> archive listing of past earthquakes. It was designed in a calendar-like
> format where you could click on a date and get a listing of all the more
> significant quakes for that particular day. The location was:
>    http://www.cdidc.org:65120/web-bin/bulldaily/calendar=yes/bulletin=GAMMAs
>
>    I get a "no such URL" message when I try that location now. My question is,
> does anyone know what happened to that website and is there something
> similar to that around anymore. Any input will be appreciated.
>
>                                         Thanks, Phil  SFN&Z
>
> _____________________________________________________________________
>
> Public Seismic Network Mailing List (PSN-L)
>
> To leave this list email listserver@............. with the body of the
> message: leave PSN-L




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From: bob ogburn 
Subject: Re: EW activity for 40 Min.
Date: Thu, 06 Aug 1998 19:49:41 -0700

Sorry....

here= 37.67704 -122.47334
when= 0358 6Aug98 Z
what= local construction (piledriving at SFO)



David A. Nelson wrote:

> At 08:13 PM 8/5/98 -0700, you wrote:
> >About 40 min. ago, strong East-West motion here. Still moving.
>
> bob  where are u   ??
>
>  what was the universal time (UTC)  ??
>
> cheers
> dave
>
> Co-ordinator:
> New Zealand
> Public Seismic Network
>                         Dave A. Nelson   ZL4TBN
>                         24 Jensen St.,
>                         Green Is., Dunedin,
>                         South Is.. New Zealand.
>
> http://psn.quake.net/dave/home.htm
>
> IF there indeed are other parallel universes... I can now rest in the
> knowledge, that in at least one of them, I am filthy rich and drive a red
> Ferrari
>
> _____________________________________________________________________
>
> Public Seismic Network Mailing List (PSN-L)
>
> To leave this list email listserver@............. with the body of the
> message: leave PSN-L




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From: taber@............. (John Taber)
Subject: PSN and schools
Date: Fri, 7 Aug 1998 16:08:34 +1200


Edward,

You wrote:

>Having a bona fide school connection has always been one of the Holy 
>Grails of the PSN. 

Perhaps we can help with that connection.  We have started a school
seismic network here in New Zealand, and you can visit the beginnings
of our Quake Trackers home page at 
http://www.geo.vuw.ac.nz/seismology/Quake_Trackers/.

We are getting off the ground with the considerable help of Larry 
Cochrane and Dave Nelson and others including local teachers
and students, and with initial funding from the NZ 
Earthquake Commission (the national earthquake insurance company for
NZ).  We are using Larry's A/D board and software and 
the 4.5 Hz geophones that Dave has shown are effective at picking
up NZ seismicity.  Following Dave's lead in the South Island
(at Alan Munro's Southland Boys High School) 
we have installed a seismograph at the first of
the 5-6 schools we plan to have set up in the Wellington region
by the end of the year.   The plan is to add at least 5-6 schools per 
year.

We are mirroring PEPP's curriculum pages with
slight modifications to make them more applicable to NZ.  We
are also working with Larry and local teachers to develop activities 
based around WinQuake.

Any comments and suggestions for the web site are most welcome.

We will be storing the data on our web site since the data
will be primarily for local events, but it will be stored in
PSN format so all WinQuake users will be able to access it.
The database should be up before the end of the month.

I've followed your efforts ever since I was shown your first PSN AGU 
abstract, and have wanted to get involved in some way but never seemed 
to have sufficient time and/or funding.  Now through global
cooperation it all seems to be comming together.

Do you know if there is going to be a session on seismology
education in schools at AGU this year, and do you think it would be
worthwhile for us to submit an abstract?  I wasn't initially
planning to come this year (it's a long way from NZ) but if you
think there would be sufficient interest, I think I could
arrange it.


Regards,

John 



John Taber		School of Earth Sciences, Victoria University
John.Taber@.............. Box, 600, Wellington, New Zealand

phone: +64-4-472-1000
fax:   +64-4-495-5186


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From: Herald Gessinger 
Subject: Re: 16 bit Audio A/D cards
Date: Fri, 07 Aug 1998 08:34:54 +0200

Hi Greg,

I had a similar idea, but I think it is necessary to use the quake signal as a
modulation signal of a 1000 cps carrier. This can easily be done by some
analog circuitry with a frequency modulation chip. The sound card will produce
a *.wav file with the modulated 1000 cps tone.

But I stopped here with the problem to translate the stored FM signal into a
quake file. My mathematical background and my programming knowledge is too low
to write such a converter program. Is anybody here in the list with more
experience?

Herald Gessinger
Austria/Europe
h.gessinger@.........

Gregory Bajuk wrote:

> Since most computer audio cards can convert music/voice/sound input to a
> digital .wave file, can these cards be used to record and display
> seismograph files as well.  Has anyone tried this? If so please reply with
> your experiences.  Thanks.
> Greg Bajuk
>
> _____________________________________________________________________
>
> Public Seismic Network Mailing List (PSN-L)
>
> To leave this list email listserver@............. with the body of the
> message: leave PSN-L
>


_____________________________________________________________________

Public Seismic Network Mailing List (PSN-L)


From: "James M Hannon" 
Subject: Re: 16 bit Audio A/D cards (DSP 101)
Date: Fri, 7 Aug 1998 07:47:03 -0500






Herald Gessinger  on 08/07/98 01:34:54 AM

Please respond to PSN-L Mailing List 

To:   PSN-L Mailing List 
cc:
Subject:  Re: 16 bit Audio A/D cards




Hi Greg,

I had a similar idea, but I think it is necessary to use the quake signal
as a
modulation signal of a 1000 cps carrier. This can easily be done by some
analog circuitry with a frequency modulation chip. The sound card will
produce
a *.wav file with the modulated 1000 cps tone.

But I stopped here with the problem to translate the stored FM signal into
a
quake file. My mathematical background and my programming knowledge is too
low
to write such a converter program. Is anybody here in the list with more
experience?

Herald Gessinger
Austria/Europe
h.gessinger@.........



There are about as many ways to do this as there are DSP designers.  Here
      is the approach I would take.

Complex mix the signal down to DC.  To do this you multiply the data
      samples by the sin and cos of 1000 Hz.  The resulting sample pairs
      are called  I and Q for Inphase and Quadurature. At this point the FM
      signal is centered around DC rather than 1000 Hz so you can clean it
      up a little by running it through a FIR low pass filter.  Now the
      frequency of the signal is represented by how fast the vector
      represented by the I and Q signals rotates.  If your original signal
      was at 1000 Hz the vector would not rotate at all. For frequencies
      (in the original signal) above 1000 Hz the vector will rotate in one
      direction and for frequencies below 1000 Hz the vector will rotate in
      the opposite direction. To compute the frequency you calculate the
      angle represented by each successive vector and then subtract the
      angles of successive samples.  This difference in angles represents
      the frequency of the signal or in our case the original voltage out
      of the seismograph. The sign of the voltage is indicated by which way
      the vector is rotating so we recover our original plus or minus
      voltage signal.  At this point you need to run the demodulated
      samples through a decimation filter to get the sample rate down to
      something in line with the original seismic waveform frequency
      response and store the data as a PSN file.

Jim Hannon




_____________________________________________________________________

Public Seismic Network Mailing List (PSN-L)


From: Norman Davis WB6SHI 
Subject: Re: VCO into sound card
Date: Fri, 07 Aug 1998 07:09:02


>> For input to a PC sound card, we have considered the possibility 
>> of using a VCO (voltage controlled oscillator) IC after the 
>> seismometer pre-amp to convert the seismic signal into an FM audio 
>> tone whose frequency change is proportional to the input voltage. 
>> We use this FM-VCO method in all the analogue telemetry that we do, 

We are already doing this... I run my lehman into an xr chip and then into
the sound card and view it on fftdsp software. Also remote sites of usgs
can be heared on vhf radio and mixed into the soundcard and viewed at the
same time.


Norman Davis WB6SHI
Shingle Springs, Ca
normd@.............
http://www.directcon.net/normd/index.htm


_____________________________________________________________________

Public Seismic Network Mailing List (PSN-L)


From: Norman Davis WB6SHI 
Subject: Re: 16 bit Audio A/D cards
Date: Fri, 07 Aug 1998 07:15:21

At 09:34 PM 8/5/98 -0700, you wrote:
>Since most computer audio cards can convert music/voice/sound input to a
>digital .wave file, can these cards be used to record and display
>seismograph files as well.  Has anyone tried this? If so please reply with
>your experiences.  Thanks.
>Greg Bajuk
>

 There are two of us in the central valley of califonia that monitor usgs
signals using fftdsp off of vhf radio. I built a vco xr chip to convert my
lehman to tone and feed that into fftdsp as well. At one time I had 3
channels going. 2 usgs and my lehman, all on one screen. It does work. The
only problem is that the fftdsp is not event trigered. You have to record
all the time. The geophone will have to be amplified and filtered before
you can see much from it.


Norman Davis WB6SHI
Shingle Springs, Ca
normd@.............
http://www.directcon.net/normd/index.htm


_____________________________________________________________________

Public Seismic Network Mailing List (PSN-L)


From: lahr@..................
Subject: Re: 16 bit Audio A/D cards
Date: Fri, 7 Aug 1998 09:56:16 -0600 (MDT)

Norman,

Where did the fftdsp software come from?  Are you using a dsp board
in your PC?

Thanks,
JCLahr

> From psn-l-return@.............. Fri Aug  7 08:18 MDT 1998
> From: Norman Davis WB6SHI 
> Subject: Re: VCO into sound card
> 
> >> For input to a PC sound card, we have considered the possibility 
> >> of using a VCO (voltage controlled oscillator) IC after the 
> >> seismometer pre-amp to convert the seismic signal into an FM audio 
> >> tone whose frequency change is proportional to the input voltage. 
> >> We use this FM-VCO method in all the analogue telemetry that we do, 
> 
> We are already doing this... I run my lehman into an xr chip and then into
> the sound card and view it on fftdsp software. Also remote sites of usgs
> can be heared on vhf radio and mixed into the soundcard and viewed at the
> same time.
> 
> Date: Fri, 07 Aug 1998 07:15:21
> 
> >Since most computer audio cards can convert music/voice/sound input to a
> >digital .wave file, can these cards be used to record and display
> >seismograph files as well.  Has anyone tried this? If so please reply with
> >your experiences.  Thanks.
> >Greg Bajuk
> >
> 
>  There are two of us in the central valley of califonia that monitor usgs
> signals using fftdsp off of vhf radio. I built a vco xr chip to convert my
> lehman to tone and feed that into fftdsp as well. At one time I had 3
> channels going. 2 usgs and my lehman, all on one screen. It does work. The
> only problem is that the fftdsp is not event trigered. You have to record
> all the time. The geophone will have to be amplified and filtered before
> you can see much from it.
> 
> Norman Davis WB6SHI
> Shingle Springs, Ca
> normd@.............
> http://www.directcon.net/normd/index.htm
> 


_____________________________________________________________________

Public Seismic Network Mailing List (PSN-L)


From: "Ron Horton" 
Subject: New Amateur
Date: Fri, 7 Aug 1998 12:09:48 -0000

Hi to all and thanks for a great site. I am attempting to build a =
version of the Lehman sensor. For the mechanically challenged such as =
myself this means lots of questions. Hope no one gets hurt falling off =
their chair while laughing at my questions. Question #1: How critical is =
boom length ? (ie do I HAVE to cut the 36" rod down to 30") Question #2: =
How can I accurately (inexpensively) determine latitude/longitude of my =
site ?  Will newer versions of Delorme's Street Atlas or similar =
programs give me accurate results ? Thanks for any help in advance. My =
personal e-mail address is ron.horton@........










Hi to all and thanks for a great =
site. I am=20
attempting to build a version of the Lehman sensor. For the mechanically =

challenged such as myself this means lots of questions. Hope no one gets =
hurt=20
falling off their chair while laughing at my questions. Question #1: How =

critical is boom length ? (ie do I HAVE to cut the 36" rod down to=20
30") Question #2: How can I accurately (inexpensively) determine=20
latitude/longitude of my site ?  Will newer versions of Delorme's =
Street=20
Atlas or similar programs give me accurate results ? Thanks for any help =
in=20
advance. My personal e-mail address is ron.horton@........


 


From: "James M Hannon" 
Subject: Re: New Amateur
Date: Fri, 7 Aug 1998 12:52:19 -0500






"Ron Horton"  on 08/07/98 07:09:48 AM

Please respond to PSN-L Mailing List 

To:   psn-l@.............
cc:    (bcc: James M Hannon/CedarRapids/Collins/Rockwell)
Subject:  New Amateur




Hi to all and thanks for a great site. I am attempting to build a version
of the Lehman sensor. For the mechanically challenged such as myself this
means lots of questions. Hope no one gets hurt falling off their chair
while laughing at my questions. Question #1: How critical is boom length ?
(ie do I HAVE to cut the 36" rod down to 30") Question #2: How can I
accurately (inexpensively) determine latitude/longitude of my site ?  Will
newer versions of Delorme's Street Atlas or similar programs give me
accurate results ? Thanks for any help in advance. My personal e-mail
address is ron.horton@........





_____________________________________________________________________

Public Seismic Network Mailing List (PSN-L)


From: "James M Hannon" 
Subject: Re: New Amateur OOPS
Date: Fri, 7 Aug 1998 13:06:28 -0500

Oops,
For some reason my text did not get sent with my reply.

Hi Ron,
In answer to your questions.
You do not have to have the boom exactly 30" long 36" would work just fine.
I recently purchased a Delorme topo atlas of my state (Iowa) for about $10.
It has "GPS grids" in other words lat and lon lines.  The maps are so
detailed that they even show my driveway which is about 700 ft long. You
should be able to interpolate the grids to a fiarly accurate lat and lon.

Jim Hannon



_____________________________________________________________________

Public Seismic Network Mailing List (PSN-L)


From: "Ron Horton" 
Subject: Thanks
Date: Fri, 7 Aug 1998 15:05:52 -0000

Thanks for reply, Jim. Appreciate info. Have a great day !
Ron










Thanks for reply, Jim. Appreciate =
info. Have a=20
great day !


Ron


 


From: Norman Davis WB6SHI 
Subject: Re: 16 bit Audio A/D cards
Date: Fri, 07 Aug 1998 15:19:22

At 09:56 AM 8/7/98 -0600, you wrote:
>Norman,
>
>Where did the fftdsp software come from?  Are you using a dsp board
>in your PC?
>
>Thanks,
>JCLahr

 Check my web site. there is a link to the site where fftdsp can be had. I
am usning a awe sound blaster but any sound card that is soundblaster
compatable should work. I have it working on 3 different cards.


Norman Davis WB6SHI
Shingle Springs, Ca
normd@.............
http://www.directcon.net/normd/index.htm


_____________________________________________________________________

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From: "Ron Horton" 
Subject: Lehman Plans
Date: Fri, 7 Aug 1998 18:28:31 -0000

Hi Robert,

Thanks for reply. I am using plans from PSN site. Plummers version. Am =
going to try modification to John Cole's idea of using ball bearing. I =
still need to find a base, but otherwise have all the parts. Once I =
succeed in building mechanical portion I'll order Larry's boards and try =
my luck. Probably first week in September. I live in Houston, Texas. =
Yes, the gc stands for "gulf coast". Thanks again. Have a great day.

Ron










Hi Robert,


 


Thanks for reply. I am using plans from PSN site. =
Plummers=20
version. Am going to try modification to John Cole's idea of using ball =
bearing.=20
I still need to find a base, but otherwise have all the parts. Once I =
succeed in=20
building mechanical portion I'll order Larry's boards and try my luck. =
Probably=20
first week in September. I live in Houston, Texas. Yes, the gc stands =
for=20
"gulf coast". Thanks again. Have a great day.


 


Ron


 


From: robert barns <75612.2635@..............>
Subject: Re: New Amateur
Date: Fri, 7 Aug 1998 20:52:55 -0400

Ron,
  I hope you don't have too much trouble getting your Lehman working--I
have found this hobby a source of great satisfaction.
  Certainly, the boom length is not critical--30" is as good as 36". =

However, you might consider that a 30" boom (or even less) will make
building an insulating enclosure easier.  Such an enclosure (dog house?) =
is
absolutely essential since a Lehman is extremely sensitive to air current=
s.
 Be sure to put a small (10W) heater in the top of the box to stagnate th=
e
air.  I built my box out of 2" thick styrafoam (avail. at a lumber yard)
glued together with Elmer's glue.  It seems to work very well.
  I have Street Atlas USA (a great device).  I made a large number of
measurements of my lat and lon with a GPS reciever and the avgerage of
these differs from the Street Atlas lat and lon by only 0.6 arc secs.  Th=
is
is perfect agreement considering the various uncertainties.  This accurac=
y
is far greater than you need for a seismograph.
  Your effort will surely pay off if for no other reason than the joy of
using Larry's WinQuake program.
Bob Barns

The early bird gets the worm but the second mouse gets the cheese.

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From: S-T Morrissey 
Subject: Lehman design ideas
Date: Fri, 7 Aug 1998 20:49:08 -0500 (CDT)

Ron,

Some thoughts on your building the Lehman seismometer:

(I have edited together some previously posted information)

The Lehman is a "poor-boys'" version of the Columbia-Sprengnether
S5000 long-period, of which there are over 1000 in use.
I have scanned a pictorial drawing of it to my web site on
the psn info page. 

http://www.eas.slu.edu/People/STMorrissey/index.html

Of particular interest is the lower suspension of the boom.
Here the boom passes over the frame member attached to the base,
and pulls on the frame via a taught wire arrangement. For
the Lehman, I would make a right angle fixture at the end of
the boom, and have it drop down behind the place where the
bolt and pivot currently are, and pull from the "backside"
with a short ( about 1 cm ) length of music wire.  The operating
principal of this horizontal configuration assumes that forces
about the boom pivot are minimal, and the period is actually
controlled by the angle of the boom with respect to the horizontal.

Some formulae of interest for the horizontal pendulum:
(assuming that the restoring force by the hinges and/or 
pivot are minimal):

The natural period: Tn = 2*pi*sqrt(l/(g*sine i))
 
where l is the boom length in cm, g=980cm/sec^2, i is the angle
that the boom makes wrt the horizontal, measured in radians,
(where sine i = i). For example, a 40 cm boom hanging vertically
as a simple pendulum ( an angle of 90 degrees) has a period of 
1.3 seconds. (a one second clock pendulum is 24.8 cm). When tilted
horizontally to about 4 degrees, the period is 5 seconds. At
about a 1 degree angle, it is 10 seconds, and at about 0.23 deg.
it is 20 seconds. So the period is changing with inverse of the
square root of the angle, which is why long periods are so unstable.
But unstable also means sensitive to smaller ground motions.

So the stability question for a horizontal seismometer depends 
mostly on the mechanical period and the working range of the 
velocity coil; ie how far it can drift before touching. The 
old S5000s that I operate at 15 seconds in vaults rarely 
need to be recentered.  (the working range is +,- 5mm for 
these horizontals). Years ago we ran them at 30 seconds, 
and had to center them about every other month.  I understand 
that most Lehmans operate at 10 seconds give or take, 
but that some can be workable at 20 seconds with more 
frequent adjustment. Of course, the stability of the pier
becomes a major concern. Also, thermal effects on the base
and frame of the instrument can cause major drifting.

My specific hope for someone making a new Lehman would be to 
to make it as rugged and massive as possible so that longer
periods are easily attainable, (which provides a significantly more 
interesting response to teleseisms), but without the problem 
of needing frequent recentering. A 20 second instrument would be nice,
but would need 4 times the tilt stability of a 10 second sensor.
I don't have any information on the actual sensitivity of the 
Lehman designs that are in use. But for comparison to the S5000s 
I am operating at 15 seconds, which have a 32 tpi (turns per inch) 
leveling screw, about 1/100th turn (the leveling knob happens 
to have about a 100 mm circumference) is about 16 microradians, 
and moves the mass about 1mm.  One can calculate how much the 
mass should move when tilted at a given period.

Another useful calculation is the tilt sensitivity of the horizontal
pendulum (which can be used to calibrate the displacement detector)

			z = (g * Tn^2 / 4 * pi^2) * phi

where z is the horizontal displacement of the mass, Tn is the 
natural period, and phi is the tilt of the base at right angles
to the boom, again measured in radians.

From my example above about the S5100: the base is 500 mm, so
the tilt from 1/100 turn of the screw ( which is 0.008 mm) is 
0.008/500 = 0.000016 radian. If Tn = 15 seconds, the mass will
move 0.88 mm, which is close to my approximation.

Evaluating this on my STM-8 horizontal, with l = 40 cm, and 
Tn = 10 seconds, 1/12 turn of the 28 tpi leveling screw is
0.9mm/12 = 0.075mm; the base width is 130mm, so the tilt is
0.075/130 = 0.00058 radians. This calculates to an offset
of the mass of 1.43 cm, which is about what I measure. At
20 seconds, the offset is about 4 times, or 5.7 cm. 

Two points are clear: the stability is inversely proportional
to the square of the period, or conversely, the sensitivity
increases with square of the period.  And the amount of the mass
is not a consideration for the period or the displacement
sensitivity.  As long as it is significantly greater (like 10x)
than the weight of the boom, it will work.

And a final thought: I would forgo the hydraulic damping and
simply use resistive damping with the main coil by shunting
it with an appropriate resistor, which is what is done in
modern seismology. The value of the resistor  can be readily 
calculated; the voltage loss of the resistive damping is easily
made up for with additional gain of the preamplifier.

regards,
Sean-Thomas

_____________________________________________________________________

Public Seismic Network Mailing List (PSN-L)


From: bob ogburn 
Subject: Re: New Amateur
Date: Fri, 07 Aug 1998 20:40:26 -0700

Hi Ron,

to locate your station try visiting http://tiger.census.gov/
if you can correlate your station location to the map, the page will
return a high precision
latitude/longitude result.  I checked the grid coordinates obtained from
this page with a GPS receiver - good result.

bob ogburn
PSN Daly City

Ron Horton wrote:

>  Hi to all and thanks for a great site. I am attempting to build a
> version of the Lehman sensor. For the mechanically challenged such as
> myself this means lots of questions. Hope no one gets hurt falling off
> their chair while laughing at my questions. Question #1: How critical
> is boom length ? (ie do I HAVE to cut the 36" rod down to 30")
> Question #2: How can I accurately (inexpensively) determine
> latitude/longitude of my site ?  Will newer versions of Delorme's
> Street Atlas or similar programs give me accurate results ? Thanks for
> any help in advance. My personal e-mail address is
> ron.horton@........




_____________________________________________________________________

Public Seismic Network Mailing List (PSN-L)


From: "Phil Giannini" 
Subject: Earthquake lists
Date: 7 Aug 1998 20:58:26 -0800

  REGARDING           Earthquake lists

Hi Arie,
    Thanks for the help, that was indeed the place.  Nice sleuthing. I have
changed the address and bookmarked it again.    Regards, Phil


_____________________________________________________________________

Public Seismic Network Mailing List (PSN-L)


From: "Ron Horton" 
Subject: Thanks
Date: Sat, 8 Aug 1998 00:48:25 -0000

Thanks to Jim Hannon, Robert Avakian, Robert Barnes, Bob Ogburn, Frank =
Cooper, and others for information and encouragement. I have a lot to =
learn and all help is appreciated. Thanks to Larry Cochrane for =
EVERYTHING. I have already enjoyed reading much of the PSN archives, =
using Winquake (with events from many others), and getting up courage to =
try to build my own "seismograph."

Thanks, Ron Horton









Thanks to Jim Hannon, Robert =
Avakian, Robert=20
Barnes, Bob Ogburn, Frank Cooper, and others for information and =
encouragement.=20
I have a lot to learn and all help is appreciated. Thanks to Larry =
Cochrane for=20
EVERYTHING. I have already enjoyed reading much of the PSN archives, =
using=20
Winquake (with events from many others), and getting up courage to try =
to build=20
my own "seismograph."


 


Thanks, Ron =
Horton


From: "Walt Williams" 
Subject: PSN-L: Lehman Plans & Base Plates
Date: Sat, 8 Aug 1998 07:37:24 +0000

Hello Ron,

Regarding the base: After much wasted time and with help from the 
nice people of the PSN-L --use thick aluminum or something similar. 
My current base is 5/16 inch thick aluminum and that is not thick 
enough. The 'word' on the street is 1/2" to 1" thick.  Thicker the 
better.

Good luck.

Walt Williams, 98.08.08
dfheli@..............

p.s.

See my 'modified' plummer's Lehman at:
http://www.pacificnet.net/~dfheli/seismo.html

You can click on highlighted text next to thumbnails for larger 
image.
=================================================== 

------- Forwarded Message Follows -------
From:          "Ron Horton" 
To:            "PSN-L" 
Subject:       Lehman Plans
Date:          Fri, 7 Aug 1998 18:28:31 -0000
Reply-to:      PSN-L Mailing List 

Hi Robert,

Thanks for reply. I am using plans from PSN site. Plummers version. Am
going to try modification to John Cole's idea of using ball bearing. I
still need to find a base, but otherwise have all the parts. Once I
succeed in building mechanical portion I'll order Larry's boards and
try my luck. Probably first week in September. I live in Houston,
Texas. Yes, the gc stands for "gulf coast". Thanks again. Have a great
day.

Ron



_____________________________________________________________________

Public Seismic Network Mailing List (PSN-L)


From: 
Subject: MASS FOR LEHMAN SEIS
Date: Sat, 8 Aug 1998 16:57:38 EDT

TO:  PSN FRIENDS
For those of you building a Lehman Seis. of planning to build one or wanting
to upgrade an existing one, I just returned from a shopping trip to Pasadena,
California (U.S.A.).  While there I bought a soild brass mass for a future
Lehman that I am building.  The mass is a cylinder 3 inches tall by 4 inches
in diameter with two tapped holes on one of the 4inch sides for 5/16 inch
bolts.  The cylinder weighs 11.5 lbs.  The cost for this cylinder was $25.00.
There are three left in the store and they are not shown in the stores
Catalog.  If you are interested the name of the store is:
	C and H Sales Company.  2176 E. Colorado Blvd., Pasadena, Calif. 91107
	Mailing address:  P.O. Box 5356, Pasadena, Calif. 91117
	email address:  c&h@...........
	Telephone # :  Toll Free (800) 325-9465
You may order by telephone and they will ship anywhere.  This surplus company
has been in business since 1948.
Jim Allen
Cerritos, California

_____________________________________________________________________

Public Seismic Network Mailing List (PSN-L)


From: Edward Cranswick 
Subject: PSN/School presentations at AGU
Date: Sat, 08 Aug 1998 17:08:50 -0600

Ted & Jan-
    Below is a description of a special session at the December AGU meeting in San
Francisco that would be a perfect opportunity for a PSN/school computer-poster
presented by the students of Almaden School.  I will be out of the office for the
next week, but please let me know what you think.
-Edward

S12   Digital Communications in Seismology: Glimpses of the 21st Century Seen Today?
The explosive growth in digital communications brought on by widespread public
interest in the internet has profoundly changed seismic instrumentation. Digital
communication links to seismic stations for real-time data collection, near-real-time
data collection, or for least
state of health data are becoming standard experimental procedure. The rapid
evolution of this technology, however, has led to a proliferation of different
approaches to solving the same problem. The primary goal of this session is to
provide a forum for comparison of the different technologies currently available. Our
hope is that this will help move the community toward a set of standards that will
allow for a more transparent exchange of data between networks and for distribution
to the broader community. In addition, widespread availability of digital
communication links to sensors and between sensor networks promises to profoundly
change the scientific infrastructure of seismology. Papers are also solicited on
ideas for scientific problems that could be addressed by a network of networks of
seismic instruments on a national to global scale with thousands of broadband seismic
stations.

Conveners: Gary L. Pavlis, Department of Gelogical Sciences, Indiana University, 1005
10 Street, Bloomington, IN 47405, Phone: +1-812-855-5141, Fax: +1-812-855-7899,
E-mail: pavlis@............ and Steve Malone, Geophysics Program, University of
Washington, Box 351650, Seattle, WA 98195, Phone: +1-206-685-3811, Fax:
+1-206-543-0489, E-mail: steve@......................

Ted Blank wrote:

> I will speak to my son's science teacher.  When I mentioned it to her
> last year she was very excited about the idea.  Thanks for proposing to
> sponsor us.
>
> Ted Blank
> San Jose, California
>
> On Thu, 23 Jul 1998, Edward Cranswick wrote:
>
> >
> >
> > --
> > Edward Cranswick                Tel: 303-273-8609
> > US Geological Survey, MS 966    Fax: 303-273-8600
> > PO Box 25046, Federal Center    cranswick@........
> > Denver, CO 80225-0046  USA      E.M. Forster said, "Only connect".
> >
> >
>
>   ------------------------------------------------------------------------
>
> Subject: Re: Santa Cruz Seismic Instruction Software
> Date: Thu, 23 Jul 1998 16:47:09 -0600
> From: Edward Cranswick 
> Organization: US Geological Survey, Golden, CO
> To: Jan Froom 
> CC: cranswick@...............
> References: <5030300023233283000002L032*@MHS>
>
> Jan-
>         I thought that you, Steve, and Ted might do something, and I think that
> I forwarded some kind of info to the PSN-L.  However, I was not really
> connected with it myself, and I wasn't going to try to tell you guys
> what you should do (what maybe I should have helped to do myself).  In
> any case, the IRIS meeting does not get as much coverage as the AGU
> meetin in San Francisco in December which Larry and Ted attended last
> year with me.  So I think it would be a great idea to pursue the idea
> that you and Ted talked about last year of having a bunch of students
> submit a poster for the AGU meeting 6-10 December this year
> . You guys can write the
> abstract and prepare the poster and I, as an AGU member, can sponsor it
> and get the USGS to pay for it. The abstract deadline for that is:
>
>         August 26, 1998         (Postal/express mail submissions)
>
>         September 2, 1998       (Interactive Web Form submissions)
>
>         Because we only have about a month, please let me know ASAP what you
> think and also CC a copy to me at  which what
> I am trying to make my address for PSN-related activities.
> -Edward
>
> Jan Froom wrote:
> >
> > It's a shame that we couldn't have gone to this conference, since I think
> > Steve, Ted & I  are about the only ones in this area that are actually working
> > with schools.... well Elementary, Middle & High.  I tried, and got a note from
> > a lady in Arizona that forwarded my request to a lady in Santa Cruz....  but
> > after that I got no answer.
> > ---------------------- Forwarded by Jan Froom/San Jose/IBM on 07-22-98 11:26 AM
> > ---------------------------
> >
> > Ted Blank
> > 07-21-98 01:13 PM
> > To: Jan Froom/San Jose/IBM@IBMUS
> > cc:
> > From: Ted Blank/Santa Teresa/IBM @ IBMUS
> > Subject: Re: Santa Cruz Seismic Instruction Software
> >
> > I tried to get the information from Larry but it was all very vague.  Finally
> > he called me the night before to say it was the next day but by that time I had
> > other plans.  Oh well.
> >
> > Regards, Ted
> > DB2 Performance, IBM Santa Teresa Lab, San Jose, California
> >
> > Ted Blank/Santa Teresa/IBM .....(from Notes)
> > IBMUSM50(TED) .............................(from PROFS/VM)
> > ted@.......... ..............................(from internet sites)
> > STLVM6(BLANK) .............................(for LIST3820 files etc.)
> > Tie: 8-543-3589    Ext:  (408) 463-3589   Fax:  (xxx-2614)
>
> --
> Edward Cranswick                Tel: 303-273-8609
> US Geological Survey, MS 966    Fax: 303-273-8600
> PO Box 25046, Federal Center    cranswick@........
> Denver, CO 80225-0046  USA      E.M. Forster said, "Only connect".



--
Edward Cranswick                Tel: 303-273-8609
US Geological Survey, MS 966    Fax: 303-273-8600
PO Box 25046, Federal Center    cranswick@........
Denver, CO 80225-0046  USA      E.M. Forster said, "Only connect".




_____________________________________________________________________

Public Seismic Network Mailing List (PSN-L)


From: Edward Cranswick 
Subject: Re: PSN and schools
Date: Sat, 08 Aug 1998 17:22:09 -0600

John-
    I heartily recommend that you submit an AGU abstract about "Quake
Trackers" to the special session: "S12   Digital Communications in
Seismology: Glimpses of the 21st Century Seen Today?"  I looked fast
through the QT website and was impressed by what you and Dave and others
are doing.  I will be out of the office for the next week, but I will
scrutinize what you all are doing more carefully when I return.  See you
in San Francisco!
-Edward

John Taber wrote:

> Edward,
>
> You wrote:
>
> >Having a bona fide school connection has always been one of the Holy
> >Grails of the PSN.
>
> Perhaps we can help with that connection.  We have started a school
> seismic network here in New Zealand, and you can visit the beginnings
> of our Quake Trackers home page at
> http://www.geo.vuw.ac.nz/seismology/Quake_Trackers/.
>
> We are getting off the ground with the considerable help of Larry
> Cochrane and Dave Nelson and others including local teachers
> and students, and with initial funding from the NZ
> Earthquake Commission (the national earthquake insurance company for
> NZ).  We are using Larry's A/D board and software and
> the 4.5 Hz geophones that Dave has shown are effective at picking
> up NZ seismicity.  Following Dave's lead in the South Island
> (at Alan Munro's Southland Boys High School)
> we have installed a seismograph at the first of
> the 5-6 schools we plan to have set up in the Wellington region
> by the end of the year.   The plan is to add at least 5-6 schools per
> year.
>
> We are mirroring PEPP's curriculum pages with
> slight modifications to make them more applicable to NZ.  We
> are also working with Larry and local teachers to develop activities
> based around WinQuake.
>
> Any comments and suggestions for the web site are most welcome.
>
> We will be storing the data on our web site since the data
> will be primarily for local events, but it will be stored in
> PSN format so all WinQuake users will be able to access it.
> The database should be up before the end of the month.
>
> I've followed your efforts ever since I was shown your first PSN AGU
> abstract, and have wanted to get involved in some way but never seemed
> to have sufficient time and/or funding.  Now through global
> cooperation it all seems to be comming together.
>
> Do you know if there is going to be a session on seismology
> education in schools at AGU this year, and do you think it would be
> worthwhile for us to submit an abstract?  I wasn't initially
> planning to come this year (it's a long way from NZ) but if you
> think there would be sufficient interest, I think I could
> arrange it.
>
> Regards,
>
> John
>
> John Taber              School of Earth Sciences, Victoria University
> John.Taber@.........    P.O. Box, 600, Wellington, New Zealand
>
> phone: +64-4-472-1000
> fax:   +64-4-495-5186
>
> _____________________________________________________________________
>
> Public Seismic Network Mailing List (PSN-L)
>
> To leave this list email listserver@............. with the body of the
> message: leave PSN-L



--
Edward Cranswick                Tel: 303-273-8609
US Geological Survey, MS 966    Fax: 303-273-8600
PO Box 25046, Federal Center    cranswick@........
Denver, CO 80225-0046  USA      E.M. Forster said, "Only connect".




_____________________________________________________________________

Public Seismic Network Mailing List (PSN-L)


From: Edward Cranswick 
Subject: PSN and CNSS (Re: Use this list -- PSN Station list)
Date: Sat, 08 Aug 1998 18:02:23 -0600

PSN, Steve Hammond, Steve Malone-
    I think it would be useful if the PSN were represented in the list of global
seismograph stations that is being compiled by CNSS, i.e., see below:

>       Also, on a different subject, since I know you are interested and
>involved in the Peoples Seismograph Network I have a question.  I have
>been tasked with doing an inventory of seismic networks in the US and am
>getting a response from most of the regional networks (ie members of the
>CNSS).  The `PSN' has never been an actual part of the CNSS since it is a
>pretty ad hoc group with no central authority (as it should).  However,
>for this inventory (and maybe just to increase its visability it might be
>nice to include stations form the PSN in what I am doing.  You may find a
>descritpion of what I need on the WEB at:
>       http://www.cnss.org/NETS/request.survey.txt
>
>Any ideas you might have on how I could do this, please let me know.
>
>
>       Steve Malone                    E-mail: steve@......................
>       Geophysics Program              Phone: (206) 685-3811
>       University of Washington        FAX: (206)543-0489
>       Box 351650                      Office: ATG-226
>       Seattle, WA 98195       http://www.geophys.washington.edu

One of the requested pieces of information is a the name of a contact person to
represent the seismograph network.  After some discussion about this, John Lahr
(USGS) and I decided that it would not be appropriate for either of us to be this
contact person. If we want to keep the PSN for the "Public", any "semi-official" PSN
positions should not be occupied by professional seismologists. John and I can serve
as liasons between the PSN and the USGS, but I don't think a public group should be
represented by a professional.  Steve Hammond, Jerry & Dorothy Darby, Charlie Rond,
Larry Cochrane and Dave Nelson -- to name a few -- have done wonderful jobs of
taking it upon themselves to do alot of PSN work, and I think that is the best way.
If this sounds like I am shrugging off responsibility, you are right -- I am. If PSN
members do not want do something, it is not my job to tell them that they should. I
really don't know what should be done; I just sometimes have some ideas which I
sometimes voice, like what I am saying now.
    I will be out of the office for the next week.
-Edward

Steve Hammond wrote:

> See may last few notes today. Yes, you need to add Jan Froom, Dick
> Chelberg, and Bruce Kinney. I have the notes I made when adding them to
> the list. I must have not saved the work...
> Regards, S--
>
> Edward Cranswick wrote:
> >
> > Steve-
> >     Good to talk to you last Saturday.  I got kind of bogged down on the
> > Part#A for CNSS (Steve Malone).  Attached is a list of PSN participants I took
> > from your list and alphabetized, and which I was going to use, following your
> > suggestion, for item#2 (STAFF).  However, I notice several people are absent,
> > such as Dick Chelberg and Bob Ogburn (whom you noted) who I remember did alot
> > to establish PSN. I want your advice about where to go with the list.
> > -Edward
> >
> > --
> > Edward Cranswick                Tel: 303-273-8609
> > US Geological Survey, MS 966    Fax: 303-273-8600
> > PO Box 25046, Federal Center    cranswick@........
> > Denver, CO 80225-0046  USA      E.M. Forster said, "Only connect".
> >
> >     ---------------------------------------------------------------
> > Al Allworth
> > Almaden Country Middle School
> > Robert (Bob) L. Barns
> > Jeff Batten
> > Ted Blank
> > Martin S. Brewer
> > George Bush
> > Fred Bruenjes
> > Steve Clark
> > Larry Cochrane
> > Darrell Collins
> > Claudio Conti
> > Frank Cooper
> > Karl Cunningham
> > Dorothy & Jerry Darby
> > Paolo Frediani
> > Tom Frey
> > Kim & Jan Froom
> > Sam Gazdik
> > Phil Giannini
> > Grayling School, Alaska
> > Roger Griggs
> > Lucas Haag
> > Mark Halliday
> > Bob Hammond
> > Steve Hammond
> > Jean-Jacques Hunsinger
> > Albert Judge
> > Meredith Lamb
> > Robert L. Laney
> > Dennis Leatart
> > Bob Lewis
> > Barry Lotz
> > Jim Lovell
> > Gregory A. Lyzenga
> > Douglas McConnell
> > McGrath School, Alaska
> > Stephen Mortensen
> > Francesco Nucera
> > Ken Navarre
> > Dave Nelson
> > Pearl Creek School, Alaska
> > Tony Potenzo
> > Roberto E. Pozzo
> > Charlie Rond
> > Liberio Rossi
> > Giovanni Rotta
> > Pete Rowe
> > Jack Sandgathe
> > Bill Scolnik
> > Donald Sieber
> > Malcolm Sinclair
> > Roger Sorensen
> > South Valley Jr. High
> > Southland Boys High School
> > SRA, Fairbanks, Alaska
> > Peter Styles
> > Bob Teller
> > Charlie Thompson
> > Sam Toon
> > Kees Verbeek
> > Arie Verveer
> > Dick Webb
> > Ron Westfall
> > Clark Wockner
> > David Wolny
> > Brian Zimmerman



--
Edward Cranswick                Tel: 303-273-8609
US Geological Survey, MS 966    Fax: 303-273-8600
PO Box 25046, Federal Center    cranswick@........
Denver, CO 80225-0046  USA      E.M. Forster said, "Only connect".




_____________________________________________________________________

Public Seismic Network Mailing List (PSN-L)


From: Norman Davis WB6SHI 
Subject: Di-150rs support for emon
Date: Sun, 09 Aug 1998 18:51:56

 Has anyone heared if Ted has got the drivers working for the DI-150rs
modual?  He said he was working on it but never heared if he finished it up.






Norman Davis WB6SHI
Shingle Springs, Ca
normd@.............
http://www.directcon.net/normd/index.htm


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From: Peter 
Subject: Re: Di-150rs support for emon
Date: Sun, 09 Aug 1998 22:33:55 -0700

Norman,

Did Ted ever get a di150 to work on?
I sure could use e mon as I now record round the  clock

Pete

Norman Davis WB6SHI wrote:

>  Has anyone heared if Ted has got the drivers working for the DI-150rs
> modual?  He said he was working on it but never heared if he finished it up.
>
> Norman Davis WB6SHI
> Shingle Springs, Ca
> normd@.............
> http://www.directcon.net/normd/index.htm
>
> _____________________________________________________________________
>
> Public Seismic Network Mailing List (PSN-L)
>
> To leave this list email listserver@............. with the body of the
> message: leave PSN-L




_____________________________________________________________________

Public Seismic Network Mailing List (PSN-L)


From: Norman Davis WB6SHI 
Subject: Re: Di-150rs support for emon
Date: Mon, 10 Aug 1998 07:19:23

At 10:33 PM 8/9/98 -0700, you wrote:
>Norman,
>
>Did Ted ever get a di150 to work on?
>I sure could use e mon as I now record round the  clock
>
>Pete
>

 How do you find the quakes in your recorded files??

Norman Davis WB6SHI
Shingle Springs, Ca
normd@.............
http://www.directcon.net/normd/index.htm


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From: Fred and Tina 
Subject: Re: Di-150rs support for emon
Date: Mon, 10 Aug 1998 07:51:30 -0700

Pete,  Are you sure eMON will work on the DI150 ?.  I thought it
had a very specific output string.  Whats wrong with the software that
shipped with it. I couldnt get the VB routines to work either (off the
web page)

Fred

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Public Seismic Network Mailing List (PSN-L)


From: ralvarez@........ (Raul Alvarez)
Subject: psn and the general public
Date: Mon, 10 Aug 1998 17:20:31 -0600 (MDT)

Hi all,

Have a question for the group.  Has there ever been any discussion
on having, say, PSN shirts, etc?   It seem it would be a good way to promote
our cause.

Raul
  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
                                                       
         "My dreams are the seeds of my reality,    
            nurtured in the womb of my soul"        
                  RJA, 1985                            
                                                         
                   Raul J. Alvarez
              La Estrellita Observatory
                  Bellvue, Colorado
              e-mail ralvarez@........ 
           homepage  www.frii.com/~ralvarez
            "The Renaissance Experimenter"
                  doing research in:
    Radio and Optical Astronomy, Seismology, Weather,
       Computers, Instrumentation and Neat Stuff!
  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


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Public Seismic Network Mailing List (PSN-L)


From: Pinpoint 
Subject: Re: psn and the general public
Date: Mon, 10 Aug 1998 17:20:00 -0700

At 05:20 PM 8/10/98 -0600, Raul Alvarez wrote:
>Hi all,
>
>Have a question for the group.  Has there ever been any discussion
>on having, say, PSN shirts, etc?   It seem it would be a good way to promote
>our cause.

? I'll buy one but I didn't really understand the cause? Where can one be
purchased? Common Larry get an artistic person going on this one for
sure..I like it! Seriously!
Bob


_____________________________________________________________________

Public Seismic Network Mailing List (PSN-L)


From: Pinpoint 
Subject: Re: psn and the general public
Date: Mon, 10 Aug 1998 17:20:00 -0700

At 05:20 PM 8/10/98 -0600, Raul Alvarez wrote:
>Hi all,
>
>Have a question for the group.  Has there ever been any discussion
>on having, say, PSN shirts, etc?   It seem it would be a good way to promote
>our cause.

? I'll buy one but I didn't really understand the cause? Where can one be
purchased? Common Larry get an artistic person going on this one for
sure..I like it! Seriously!
Bob


_____________________________________________________________________

Public Seismic Network Mailing List (PSN-L)


From: S-T Morrissey 
Subject: Re: VBB temperature comp
Date: Mon, 10 Aug 1998 20:07:46 -0500 (CDT)

Barry,

Maybe your bimetallic element is too stiff. The one I use has a
bimetallic coil about 1/8" wide and 3/4" dia when coiled, About
5 turns of the coil are left when I straighten out the 3" lever arm.
I measured the force it applies to the boom with small weights on
threads, and it is about 3.5 grams at the present setting. This
does not appear to affect the free period or the response in a 
significant way; the step calibration is the same.
I haven't attempted fine adjustment of it yet; I just ran another
multi-pair signal cable from the recorder to downstairs where the
pier is so I can record the temperature and mass postion (and the
micro-barometer also).

I have tried your suggestion of having the bimetallic element move a 
mass with temp change. The strip I have does not move perceptibly
with a 1 degree C change, but this 1 deg C has required about a 
1 cm shift of the 10 gram trim mass on the boom to compensate it. 
It is too wimpy to support a significant trim mass. But using the 
thin bimetallic spring directly is much more sensitive; like I 
said, you can test it by shinning a penlight on it.

The old WWNSS LP vertical seismometers (the Sprengnether S5000) DO
have a very large bimetallic compensator. It is about 4cm wide and
an inverted U about 10 cm high, with an attached mass of about
200 grams (the seis mass is 11kg). It is also quite stiff.

You mention that your VBB output varies several volts on a daily
basis. This is typical of VBB sensors; even without thermal and
barometric noise, they sense earth tides. Usually they are connected
to a 24 bit digitizer (1:16 000 000), and the offset is removed
in later processing. With our 12 and 16 bit ADCs, the VBB needs
a single pole high pass amp to remove the large DC signal. I use
1 megohm into 1 000 microfarad (= 1000 seconds; use 2 ea. 2000 uf
low leakage capacitors in series connected + to +) with a gain of 2 
for the "line" output of the seismometer. The data and calibrations
I have shown are via this arrangement.

Regards,
Sean-Thomas

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From: "Francesco" 
Subject: NEW RELEASE OF I.E.S.N  WEB SITE
Date: Tue, 11 Aug 1998 04:05:01 +0200

HELLO GUYS,
NOW IT'S ON LINE THE NEW VERSION OF OUR WEB SITE.
GOOD NAVIGATION !

I.E.S.N. - PSN ITALY
Francesco Nucera



English version at:   http://space.tin.it/scienza/frnucer/English.htm









HELLO GUYS,


NOW IT'S ON LINE THE NEW VERSION OF =
OUR WEB=20
SITE.


GOOD NAVIGATION !


 


I.E.S.N. - PSN ITALY


Francesco Nucera


 


 


 


English version at:   http://space.tin=
..it/scienza/frnucer/English.htm


From: Fred and Tina 
Subject: Re: 16 bit Audio A/D cards
Date: Mon, 10 Aug 1998 19:09:55 -0700

Norman,  Are you using three at once in the same system ?  If so some
setup info would be appreciated.

Fred

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Public Seismic Network Mailing List (PSN-L)


From: "Charles R. Patton" 
Subject: Re: New Amateur-coordinate location
Date: Mon, 10 Aug 1998 21:23:32 -0700

If your location shows up on the MSN terraserver:
 http://terraserver.microsoft.com/
 you can do a very fine location. It's free and it gives you a great
aerial view of your location.  (Just a hint on something it took me a
while to notice -- When you have zoomed down and it starts returning
aerial photographs, notice that you can click on the upper left portion
of the photograph window where it says "Map".  Then you get a standard
road map like presentation.  This makes life a lot easier in finding out
where you are. Home in where you want to go, then click the same spot
again and it will return to the photo mode.)  The problem is who to
believe -- the terraserver data or the quad maps from the USGS.  In my
case figuring from quad maps vs the terraserver I had a difference of
0.0207 degrees latitude and 0.0244 degrees longitude. Perhaps they are
using different datum points?  Maybe somebody can tell us.  Anyway,  the
quad puts me NW of the location figured from the terraserver.  You can
easily resolve 50 ft. or less using the terraserver -- so if the base
coordinates are right, you will get a very accurate location.

Charles R. Patton
charles.r.patton@........


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From: Arie Verveer 
Subject: LP filter design program
Date: Tue, 11 Aug 1998 08:05:17 +0800

Hi, I was just downloading some info from the Burr-Brown site
and came across a low pass filter design program:
Its worth downloading from:

   http://www.burr-brown.com:80/Applications/Applications.html

   program is called      FilterPro
   Application notes     AB-034



Arie.


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Public Seismic Network Mailing List (PSN-L)


From: Roger Sorensen 
Subject: Re: psn and the general public (T-shirts & Caps)
Date: Tue, 11 Aug 1998 08:59:58 -0700

> At 05:20 PM 8/10/98 -0600, Raul Alvarez wrote:
> >Hi all,
> >
> >Have a question for the group.  Has there ever been any discussion
> >on having, say, PSN shirts, etc?   It seem it would be a good way to promote
> >our cause.

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

I too thought that it would be fun to have
PSN T-shirts. 

About two years ago I came to an agreement
with the leaders of the group to use their
copyrighted logo. My original though was 
to hand-make them one at a time. While
working out the details on the logo use, there
seemed to be a fair amount of interest, so
I did the artwork and had a batch silk-screened
by a professional shop here in town. 

As it turns out, there was little interest.
I would be happy to sell the remainder of the
first and only batch at a price that just
covers the T-shirt and screen costs. I 
also have mesh baseball caps with the PSN
logo on them. You get the same price deal 
on them too.

T-shirts:
Black Hanes Beefy T's with a medium blue PSN logo
   # in stock   Size   Price
    6           Large   $12.00
   16           X-Large $12.00

Black Mesh Ball Cap with medium blue PSN logo
 22 in stock -  Price 6.00


Prices include postage to U.S.A (Foreign
orders, e-mail me with your address and
I'll see what I can do)

California residents include local sales tax.

Payment: Visa, MC, Money Order, Cashiers Check,
         Personal Check (allow 10 days for personal
         checks to clear. 

If you have any questions, feel free to e-mail me.

Roger Sorensen (a PSN station)
Caliber Graphics
21110 Celtic St.
Chatsworth, CA U.S.A. 91311 (34.27N 118.59W)
(818) 709-5117 (9 am - 6 pm Pacific Time)

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From: Greg 
Subject: Re: psn and the general public (T-shirts & Caps)
Date: Tue, 11 Aug 1998 09:23:02 -0700

> About two years ago I came to an agreement
> with the leaders of the group to use their
> copyrighted logo. My original though was

I have little or no interest in the shirts or hats, but what does the
PSN logo look like?

,Greg

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From: Roger Sorensen 
Subject: PSN (C) logo - psn.jpg 9.64K
Date: Tue, 11 Aug 1998 11:32:01 -0700

Greg wrote:

> I have little or no interest in the shirts or hats, but what does the
> PSN logo look like?
> 
> ,Greg

Here is the PSN logo. It is copyrighted and shall only be used with
permission of the PSN.

My apologies if the size of this message has caused a problem.

From: "James M Hannon" 
Subject: Re: PSN (C) logo
Date: Tue, 11 Aug 1998 16:09:38 -0500

Ok For the next question. How does one go about getting permission to use
the PSN logo?  It would be nice to make up a couple of different size .gif
files and use them on a web site for identity recognition or link buttons
and such.

Jim Hannon



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From: watson@................ (Charles Watson)
Subject: [Fwd: BULLETIN: SOHO on the road to recovery]
Date: Tue, 11 Aug 1998 14:29:30 -0700

FYI

-- 
---/----
Charles P. Watson
Seismo-Watch

From: S-T Morrissey 
Subject: bimetallic compensator mounting
Date: Tue, 11 Aug 1998 22:27:01 -0500 (CDT)

Barry,
Re: installation of bimetallic thermal compensator:

I guess that my description of the installation is not clear.
If you refer to the latest mechanical of drawing of the sensor
that shows the side profile, there is a "Boom support" post
between the spring and the feedback magnet. Near the top,
the arrow points to a 1/4" hole which is occupied by a 3" SS
bolt. This is used to clamp the boom by looping a rubber band 
over the boom and both ends of the bolt. THis is also the
contact point for the free end of the bimetallic strip.

THe coil of the bimetallic element is mounted by its center
at the second hole in the boom toward the spring, about under
the end of the word "adjust". The coil spirals clockwise, then
straightens out, and the free end is placed UNDER the 1/4" bolt
on the support post. Once the coil is mounted, its center is turned
about 1/2 turn counterclockwise for a preliminary setting that applies
about 3 to 4 grams of force to the bolt. Since the coil contracts 
when warmed, this moves the free end down, applying less force on  
the bolt, allowing the boom to rise, correcting for the main 
spring effect.

The bimetallic element is from a 5" Taylor thermometer. The 
contact with the bolt could be replaced with a loop of nylon
thread to eliminate any stiction noise.

Regards,
Sean-Thomas



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From: S-T Morrissey 
Subject: Lead weight source
Date: Tue, 11 Aug 1998 22:39:01 -0500 (CDT)

Re: lead mass for seis

A handy lead mass for Lehman and other sensors is the 5-pound
weight used for diving weight belts. It is about 3" square by
1" thick, with two slots for the belt. It can be cut with a
hacksaw (for smaller masses) or drilled. It is available at
diving shops; I purchased several at the "Sports Authority" 
for about $5 each. For a vertical sensor, lead is essential,
since the atmospheric buoyancy is inversely proportional to
the mass density. Depleted Uranium would be even better!
For horizontal sensors, other metals are OK, but bulkier.

Regards,
Sean-Thomas


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From: barry lotz 
Subject: Re: bimetallic compensator mounting
Date: Tue, 11 Aug 1998 20:23:17 -0700

Sean Thomas
   You know how when you are trying too hard to think of something it
doesn't come to mind? Well at work it finally dawned on me what you were
saying. I appreciate the time to describe where you put the coil. I
installed a "Morrissey fishing pole" tonight. I took the free end of the
bimetal coil and attached a strip of 0.001" shim stock with a small
brass nut on the end. I set the nut in the boom channel behind the
feedback coil. Since I don't have exactly the same bolt arrangement I
made a brass pedestal and mounted the center of the bimetal coil to the
top of it. The coil center is fixed and the coil free end is moving. I
likewise took up some of the weight of the nut with a turn of the coil
center. Anxious to see what happens when the temperature stabilizes.
Another reason I used a
pedestal and nut on the end of the coil is that if I want to move it
towards the boom hinge later on for a possible different sensitivity it
won't be as hard for me to move and reattach
it.                                            Regards
                                              Barry

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From: Larry Cochrane 
Subject: Event in N. Cal
Date: Wed, 12 Aug 1998 07:28:03 -0700

Hi Everyone,

We just had an moderate event here in Northern California. This one I
definitely felt and was recorded on my strong motion sensors. Event my
ADX05 picked it up! The first event for this sensor. The news just said it
was a 5.4 near Hollister. There where two small foreshocks then the big
one. More later...

-Larry Cochrane
Redwood City, PSN
  

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From: meredith lamb 
Subject: 5.4Ml Central California
Date: Wed, 12 Aug 1998 10:05:00 -0600

Can't raise NEIC at the moment, but with the 5.4Ml msg by
Larry, the
http://www.avo.alaska.edu sites says:

98/08/12 14:10:25 Lat 36.75N Long 121.46w, Depth 8.9
Mag 5.4Ml  Central California

Meredith Lamb




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From: "Giovanni Rotta" 
Subject: NEW SEISMIC STATION WEB PAGES OF RESIA (Udine) ITALY
Date: Wed, 12 Aug 1998 18:58:10 +0200

Hi friends !!
I am very happy to present to you the web pages of my experimental seismic
station now present in Resianet web site 

http://www.geocities.com/~resianet (with english version)

So, I also offer to you the opportunity to visit my splendid valley !
(be quite... there is also the english version !)

Have my best regards,
Giovanni

Giovanni Rotta
rottag@..........
Via F. Pizzigoni, 10
33010 Resia (Udine) Italy
Lat. 46.373N   Long. 13.305E
QTH Locator JN66PI

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From: "Steve Carniglia" 
Subject: Re: Di-150rs support for emon
Date: Wed, 12 Aug 1998 10:17:02 -0700

Hi...I am the one who sent Ted the DI-190....
Last time I talked to him, he was still working on it with some hope of
being able to make it work...

Steve



-----Original Message-----
From: Norman Davis WB6SHI 
To: psn-l@............. 
Date: Sunday, August 09, 1998 7:06 PM
Subject: Di-150rs support for emon


> Has anyone heared if Ted has got the drivers working for the DI-150rs
>modual?  He said he was working on it but never heared if he finished it
up.
>
>
>
>
>
>
>Norman Davis WB6SHI
>Shingle Springs, Ca
>normd@.............
>http://www.directcon.net/normd/index.htm
>
>
>_____________________________________________________________________
>
>Public Seismic Network Mailing List (PSN-L)
>
>To leave this list email listserver@............. with the body of the
>message: leave PSN-L


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From: "Francesco" 
Subject: R: NEW SEISMIC STATION WEB PAGES OF RESIA (Udine) ITALY
Date: Wed, 12 Aug 1998 19:46:32 +0200

Ma chi credi che ci venga in quella valle di =
desolazione.................padana......

AHAHAHAHA

CHE FAI COPI LA PRESENTAZIONE I.E.S.N. ???????

Bye
Fran









Ma chi credi che ci venga in quella =
valle di=20
desolazione.................padana......


 


AHAHAHAHA


 


CHE FAI COPI LA PRESENTAZIONE =
I.E.S.N.=20
???????


 


Bye


Fran


From: Norman Davis WB6SHI 
Subject: Re: Di-150rs support for emon
Date: Fri, 14 Aug 1998 06:45:03

At 10:17 AM 8/12/98 -0700, you wrote:
>Hi...I am the one who sent Ted the DI-190....
>Last time I talked to him, he was still working on it with some hope of
>being able to make it work...
>

 I was wondering if ted knows about the suff on the dataq page. There is
quite a bit of stuff on the data stream and pinouts and the likes. Also
some visual basic source code for a program called alarm. Sounds like it
might be useful to him..

http://www.dataq.com


Norm


Norman Davis WB6SHI
Shingle Springs, Ca
normd@.............
http://www.directcon.net/normd/index.htm


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From: Fred and Tina 
Subject: Note to Windaq/DI150 users
Date: Fri, 14 Aug 1998 07:56:29 -0700

For anyone using the DI150 for datalogging. Pete(Alarm@............
showed me a usefull tip.  If your system goes down while recording, 
You can run Scandisk(Win 95) to recover the otherwise unusable file.

Normally you will get a "Illeagal file header 44" error. 

Anyone know of any low cost, high capacity UPS's.

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From: "Steve Carniglia" 
Subject: Re: Di-150rs support for emon
Date: Fri, 14 Aug 1998 09:06:54 -0700

Hmmmmmmmm......maybe but last time I talked to Ted, the problem was a
graphic problem between the DI190 and EMON....he is able to talk to the
device with no problem....He also has all the software that was supplied
with the DI190 and the full docs.

73
Steve


-----Original Message-----
From: Norman Davis WB6SHI 
To: PSN-L Mailing List 
Date: Friday, August 14, 1998 7:24 AM
Subject: Re: Di-150rs support for emon


>At 10:17 AM 8/12/98 -0700, you wrote:
>>Hi...I am the one who sent Ted the DI-190....
>>Last time I talked to him, he was still working on it with some hope of
>>being able to make it work...
>>
>
> I was wondering if ted knows about the suff on the dataq page. There is
>quite a bit of stuff on the data stream and pinouts and the likes. Also
>some visual basic source code for a program called alarm. Sounds like it
>might be useful to him..
>
>http://www.dataq.com
>
>
>Norm
>
>
>Norman Davis WB6SHI
>Shingle Springs, Ca
>normd@.............
>http://www.directcon.net/normd/index.htm
>
>
>_____________________________________________________________________
>
>Public Seismic Network Mailing List (PSN-L)
>
>To leave this list email listserver@............. with the body of the
>message: leave PSN-L


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From: Karl Cunningham 
Subject: Re: Note to Windaq/DI150 users
Date: Fri, 14 Aug 1998 11:48:45 -0700

At 07:56 AM 8/14/98 -0700, you wrote:
>Anyone know of any low cost, high capacity UPS's.

Fred --

I have found 600-800 watt UPS's at electronic-oriented swap meets in So.
Calif. for the $20 range.  They often need new batteries, but you can
usually plug them in to see if they at least work.


Karl Cunningham
La Mesa, CA.
PSN station #40
karlc@.......

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From: Fred and Tina 
Subject: Re: Note to Windaq/DI150 users
Date: Fri, 14 Aug 1998 16:20:14 -0700

Thanks Karl,  Actually i'm more in need of duration types. The power
outage last week lasted 4hr's.  What about replacing the exsisting
internal batt's with a couple car batteries or maybe a deep cycle type. 

Anybody forsee any problems with this aside from one batt discharging
into the other if the cells short. Could fuse it or use a PTC
overcurrent fuse.  Any thoughts

Fred

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From: S-T Morrissey 
Subject: UPS systems
Date: Fri, 14 Aug 1998 19:26:38 -0500 (CDT)

We operate several of them here at the seismic observatory and at
the major remote sites. With the 1 killowatt "Best" brand units, 
we parallel the internal battery (ies) with external batteries, 
using low voltage, low resistance  "rectifier" fuses for protection. 
The large DC battery connectors are helpful (Grainger 6A070 series,
about $10). It is VERY important that all the batteries that are
connected in parallel be of exactly the same type and age, even 
if this means replacing the original internal battery with a new 
one, or simply omitting it. We use the 90 amp-hr Delco photo-
voltaic batteries, or else the deep-discharge "marine" type 
batteries. With continuous float charging, they only last 3 to 
4 years.

We have also made some hybrid UPS systems using commercial 1kw precision
inverters (by TOPAZ), large 3-phase DC supplies (13.6V at 250 amps), and
large "stationary" batteries by Exide. These are 660 amp/hr cells
with high calcium plates, which are used in stationary service like
telephone exchanges and backup power for mine hoists. They are 
guaranteed for 20 years. With 660 Ah cells, we get about 6 hours
of UPS power at the 1kw level. (We can get the generator going by then).
(Also, we limit our loads to about 750 watts).

Our loads operate continuously from the inverters, so the AC-DC 
supply has to provide its input (like 100 Amps) plus re-charge the
batteries in a resonable time. It is also precise enough to be set
within 10 millivolts to properly float the batteries. So with the 
batteries always connected to the inverter, there is no power 
transfer needed when the AC goes out. However, we do have a 
"failsafe" arrangement that connects the external loads to the 
AC line in the rare event that the inverter fails. We also have
a pair of digital timers that force an "equalizing" charge voltage
for several hours once a month by switching on a different resistor
in the AC-DC supply voltage feedback reference. These large 
systems weigh about 1 500 lbs.

Regards,
Sean-Thomas

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From: Greg 
Subject: Re: Note to Windaq/DI150 users (UPS)
Date: Fri, 14 Aug 1998 21:08:51 -0700

Fred and Tina wrote:
> 
> Thanks Karl,  Actually i'm more in need of duration types. The power
> outage last week lasted 4hr's.  What about replacing the exsisting
> internal batt's with a couple car batteries or maybe a deep cycle type.

I doubt anyone's warranty will cover that, but if you want to spend a
reasonable amount on a commercial UPS... I used to work at a place with
some really nice APC Smart UPS 2200 VA running 486s with all kinds of
electronics attached. One time we had a power outage and after like 2
hours there was no (less than 1% that the display would show) drop in
the battery capacity. 

I have a little APC Back UPS 450 at home and aside from the annoying
beep every time the power dips, I like it plenty. The next time I buy
one I'll get another APC, but probably a Back UPS Pro or a Smart UPS. I
have never lost anything due to power problems with the UPS on my
computer. Of course, I don't need 4 hour uptimes though ;) I paid about
$180 in 1995? Still the same battery it came with.

APC and I'm sure other UPS manu's have web sites.

http://www.apcc.com/

You can also call APC and get a recommendation. If you're an engineer
you can add another 20% ;)

The best part about buying a commercial UPS is that your computer is
protected by their warranty that if lightning gets through they'll cover
you to a point. The only thing is that you have to have everything
plugged into the UPS.

I don't work for APC so this is not a shameless plug. 

,Greg

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From: Karl Cunningham 
Subject: Re: Note to Windaq/DI150 users
Date: Sat, 15 Aug 1998 00:46:13 -0700

At 04:20 PM 8/14/98 -0700, you wrote:
>Thanks Karl,  Actually i'm more in need of duration types. The power
>outage last week lasted 4hr's.  What about replacing the exsisting
>internal batt's with a couple car batteries or maybe a deep cycle type. 

Fred --

My 486 that runs SDR draws about 40 watts with the video monitor off, and
the electronics on my seismo another 11 watts.  So, an 800 watt UPS loaded
to 50 watts will take an outage for a while.  I haven't ever measured it,
but I think it would be several hours with the internal gell cells.  Of
course, the bigger the battery you use the longer it will go.

Karl Cunningham
La Mesa, CA.
PSN Station #40
karlc@.......

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From: "Francesco" 
Subject: CENTRAL ITALY  MB 4.8
Date: Sat, 15 Aug 1998 10:59:26 +0200

05.18
MB 4.8
LOC.: CENTRAL ITALY  (Rieti=20


I.E.S.N.  PSN-ITALY









05.18


MB 4.8


LOC.: CENTRAL ITALY  (Rieti =



 


 


I.E.S.N. =20
PSN-ITALY


From: Larry Cochrane 
Subject: Strong motion data recorded on my ADXL05 sensor.
Date: Sat, 15 Aug 1998 22:15:49 -0700

Hi Everyone,

I just completed a new web page documenting the strong motion data I got
from the 5.4Ml Hollister California event the other day. This page compares
the ADXL05 monolithic accelerometer chip sensor and a commercial
Kinemetrics three component FBA-23A strong motion sensor I am monitoring.

The URL is: http://psn.quake.net/StrongMotion.html

What I got was about +-6.1mg of acceleration from the event. This event was
about 108km (67 miles) from me and was large enough to be felt, but not
large enough, at that distance, to move anything around in the house.

Regards,
Larry Cochrane
Redwood City, PSN
 

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From: meredith lamb 
Subject: New Italian web sites
Date: Sun, 16 Aug 1998 00:51:36 -0600

Hi guys,

The two Italian web sites both look great.  The I.E.S.N site is
really extensive and impressive with the number of instruments
which seems to have grown in number.

Giovanni Rotta's web site is also very worthwhile visiting and it
gets my vote for being the most beautiful web page in the
seismographic community.

Thanks and well done guys.

Meredith Lamb


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From: frankcnd@.......... (Frank Condon)
Subject: Balleny Event Revisited
Date: Sun, 16 Aug 1998 02:55:41 -0700 (PDT)

Hello All:
I was wondering how close was the Balleny Seismic Event to the Magnetic 
South Pole?

Frank Condon
"Located in the seismic corridor somewhere between Fontana & Mammoth Lakes"


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From: barry lotz 
Subject: Event? 
Date: Sun, 16 Aug 1998 08:31:33 -0700

Well It was Mt San Gorgonio Ca @ 13:34:40 UTC
   34.12N, 116.93W   M=4.8
                 Barry

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From: Roger Sorensen 
Subject: Re: Strong motion data recorded on my ADXL05 sensor.
Date: Sun, 16 Aug 1998 10:55:27 -0700

Good work on the ADXL05 page, Larry.

What sensor components did you end up with? I used the parts described
in the Application Notes from Analog, and found the noise floor to
be excessive - somewhere in the range of 5% of a G. It would take a
large jolt to get a full P/S reading from the sensor. ( a 5M, 7 miles
away didn't even do it)

I'd be interested to hear more about your design.

Roger 
Chatsworth, CA (34:16:15N 118:35:37W)

Larry Cochrane wrote:
> 
> Hi Everyone,
> 
> I just completed a new web page documenting the strong motion data I got
> from the 5.4Ml Hollister California event the other day.

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From: Mark Wilson 
Subject: RE: Re: Strong motion data recorded on my ADXL05 sensor.
Date: Sun, 16 Aug 1998 16:12 -0400

Well, I knew that I should have put paper on my PS1 last night.

I live about 3 mi from the epicenter of the San Gorgonio quake that happened this morning.
Mild shake, nothing major, about 15-20 seconds..  I am still picking up aftershocks, in the 2 range on my Lehman and the Ps1.

I always know if the epi is close.  Low altitude planes always fly over shortly after.

Ciao, nice weekend..

Mark Wilson
mark@..............
http://www.markwilson.com
Where the San Andreas and the San Jacinto meet..	;)


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From: John Hernlund 
Subject: Re: Strong motion data recorded on my ADXL05 sensor.
Date: Sun, 16 Aug 1998 17:29:31 -0700 (MST)

Hey Larry,
   Do you have both sensors situated on the same pier or location?  How do the
FFTs compare?

******************************************************************************

			       John Hernlund
     		          E-mail: hernlund@.......
      WWW: http://www.mc.maricopa.edu/academic/phy_sci/Geology/hernlund/
		    http://www.public.asu.edu/~hernlund/

"Enlightenment is man's emergence from his self-imposed immaturity.
Immaturity is the inability to use one's understanding without guidance from
another.  This immaturity is self-imposed when its cause lies not in lack of
understanding, but in lack of resolve and courage to use it without guidance
from another.  Sapere Aude!  "Have courage to use your own understanding!"-
that is the motto of enlightenment.
-Immanuel Kant: "An Answer to the Question: What is Enlightenment?"

******************************************************************************


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From: Edward Cranswick 
Subject: Re: Strong motion data recorded on my ADXL05 sensor.
Date: Sun, 16 Aug 1998 18:55:40 -0600

Larry-
    Very interesting comparsion.  I note that there is a very strong resonance
which can be seen in the monochromatic nature of the FBA23 timeseries. The
corresponding FFT reveals a set of resonance peaks at about 1.4, 3.7, 6.5 Hz.
This looks something like the 1-3-5 progression of the fundamental resonance
and its first and second harmonics that is characteristic of seismic waves
reverberating in a low-velocity layer over a high-velocity halfspace.  However,
the observed peaks do not exactly the 1-3-5 ratio. Nonetheless, assuming that
the 1.4 Hz peak is the fundamental quarter-wavelength resonance of the near
surface, and assuming an S-wave velocity of 200 m/s for the low-velocity
near-surface sediments that underlie your house, and using the formula for the
quarter-wavelength resonance:

                    f  =  v  / (4 * h)

where "f" is the fundamental quarter-wavelength frequency (Hz), "v" is the
seismic velocity of the low-velocity layer (m/s) , and "h" is the thickness of
that layer (m), we get:

                    h = v / (4 * f)  = 200 / (4 * 1.4) = ~ 36 m

This value seems reasonable with uncertainties of a factor of two (20 - 70 m)
given the uncertainties of the seismic velocity low-velocity material (100 -
400 m/s).  When in doubt, flap your arms, that's what I say.  More later.
-Edward

Larry Cochrane wrote:

> Hi Everyone,
>
> I just completed a new web page documenting the strong motion data I got
> from the 5.4Ml Hollister California event the other day. This page compares
> the ADXL05 monolithic accelerometer chip sensor and a commercial
> Kinemetrics three component FBA-23A strong motion sensor I am monitoring.
>
> The URL is: http://psn.quake.net/StrongMotion.html
>
> What I got was about +-6.1mg of acceleration from the event. This event was
> about 108km (67 miles) from me and was large enough to be felt, but not
> large enough, at that distance, to move anything around in the house.
>
> Regards,
> Larry Cochrane
> Redwood City, PSN
>
>
> _____________________________________________________________________
>
> Public Seismic Network Mailing List (PSN-L)
>
> To leave this list email listserver@............. with the body of the
> message: leave PSN-L



--
Edward Cranswick                Tel: 303-273-8609
US Geological Survey, MS 966    Fax: 303-273-8600
PO Box 25046, Federal Center    cranswick@........
Denver, CO 80225-0046  USA      E.M. Forster said, "Only connect".




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From: Larry Cochrane 
Subject: Re: Strong motion data recorded on my ADXL05 sensor.
Date: Sun, 16 Aug 1998 23:19:39 -0700

At 05:29 PM 8/16/98 -0700, John Hernlund wrote:
>Hey Larry,
>   Do you have both sensors situated on the same pier or location?  How do
the
>FFTs compare?

The two sensors are separated by about 18 inches. Both sensors are screwed
to the wood floor in my spare bedroom. This floor is sitting on the
concrete slab of the house. The concrete slap sits on the ground, no
basement or crawl space.  

-Larry Cochrane
Redwood City, PSN  

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From: Larry Cochrane 
Subject: Re: Strong motion data recorded on my ADXL05 sensor.
Date: Mon, 17 Aug 1998 21:49:11 -0700

At 10:55 AM 8/16/98 -0700, Roger Sorensen wrote:
>Good work on the ADXL05 page, Larry.
>
>What sensor components did you end up with? I used the parts described
>in the Application Notes from Analog, and found the noise floor to
>be excessive - somewhere in the range of 5% of a G. It would take a
>large jolt to get a full P/S reading from the sensor. ( a 5M, 7 miles
>away didn't even do it)
>
>I'd be interested to hear more about your design.

The sensor uses two ADXL05 chips in a "push-pull" configuration. The output
from both chips are summed together and then amplified and low pass
filtered. The signal then goes to my A/D card. I used the "push-pull"
configuration because it seems to work pretty well on the SG sensor. With
the SG sensor the two receiver plates, one producing a positive voltage and
the other a negative, are also summed together etc... Since my sensor has a
little less internal noise, around 3mg, it seems to help a little.

-Larry Cochrane
Redwood City, PSN




  

 

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From: meredith lamb 
Subject: [Fwd: Seismicity analysis tools]
Date: Tue, 18 Aug 1998 10:56:44 -0600

Heres a reference to a free program from the British Geological
Survey.



From: John Hernlund 
Subject: Event on 8/4/98
Date: Tue, 18 Aug 1998 14:31:15 -0700 (MST)

Hello All,
   I was out of town for fives weeks and returned to discover a very nice
quake record recorded on 8/4/98 here in Tempe, Arizona.  It occurred somewhere
around 17:00 UTC on 8/4/98, but I could not find any listing for this event on
the USGS sites.  Does anyone have any info???

******************************************************************************

			       John Hernlund
     		          E-mail: hernlund@.......
      WWW: http://www.mc.maricopa.edu/academic/phy_sci/Geology/hernlund/
		    http://www.public.asu.edu/~hernlund/

"It is easier to excuse an ignorant person who claims that theory is
unnecessary and dispensable in his supposed practice, than to excuse a
Sophist who concedes its value to the schools (as, perhaps, only a mental
exercise) but who at the same time maintains that matters are quite
different in practice- that as one leaves school to enter the world, one
will realize one has been pursuing empty ideals and philosophical dreams-
and, in a word, that what sounds good in theory is of no practical
use."
-Immanuel Kant, On the Proverb: That May be True in Theory, But Is of No
Practical Use

******************************************************************************


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From: lahr@...........