Subject: PSN - NEIC Problems! From: "Rex Klopfenstein, Jr" rklopfen@......... Date: Wed, 30 Jun 1999 09:23:54 -0400 Is it my location or is there problem with the NEIC Near Realtime Reporting Webpage? Last night and today I couldn't get a response! I have been using http://wwwneic.cr.usgs.gov Rex Klopfenstein, Jr. Bowling Green, OH _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Placer 400 problems From: Phil Giannini pgiannini@........ Date: Wed, 30 Jun 1999 08:07:13 -0700 Hi John, I bought a Placer 400 some time back with plans to use it with my remote gear for both location accuracy and time lock. I used it once on a trip to the Geysers just for a location fix when I first got it to try it out and it worked great. I have plans to tie it into my recorder for time locking, but I've been busy and haven't gotten back to that project. I sort of remember that as long as the back up battery (the 9v one) is good it is suppose to fire right up and remember where it was last and the time should be fairly close so that it will update quickly. I don't have the spec sheet handy here at work, but I am not sure if it will be totally happy with that 10 volts for the main power, it might really want 12. The other thing is the power from that wall transformer/power supply clean? It might have some hum on it and that might be what's corrupting your data. The only problem I think I may have with mine is with the one second pulse on pin 9 of the connector plug. Maybe you can answer a question for me? That being, what does your 1 second pulse look like on that pin. Mine is a very short very low level differentiated pulse or spike like looking thing, not at all looking like what I would have expected there. I don't know if mine is defective in that area or if that is what it is suppose to look like. Like I said I never got much of a chance to play with it but, I did open up the box looking around for that pulse and remember that there wasn't much inside. It's been a long time, but I can't say that I remember seeing any little clock battery in there. Wish I could be more help. Regards, Phil _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: R: PSN - NEIC Problems! From: "Francesco" franuc@...... Date: Wed, 30 Jun 1999 17:06:51 +0200 Hello Rex, last night I had the same problem for calibrating Pakistan event. Many time, the NEIC web page or the Neic quake finger is down! Francesco _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Placer 400 problems From: The Lahrs JohnJan@........ Date: Wed, 30 Jun 1999 10:09:28 -0600 Phil, Thanks for the feedback on your Placer 400. I finally figured out why I was getting the messages re battery backup. I had connected the main power and the back up power at the same time. Although I had turned GPPSK.EXE on and off many times, I had never turned off the main power, leaving just the battery backup to run the system. Until you do that once, the system doesn't know that there is a battery backup installed. Will the unit run OK from the 12V car lighter socket, or does the voltage need to be conditioned with a DC-DC converter? Is GPSSK.EXE the program you used at the Geysers? Some time ago I looked at pin 9 on the scope. There was a very short spike every second. I was hoping to be able to count up perhaps 15 minutes of spikes and then put out a 15 minute mark (trace offset) on my digital record. This would give me a clock correction every 15 minutes. The problem is that I don't know how to build such a circuit. Any ideas out there? Cheers, John PS. Re the NEIS web problems, I know that there were network problems in the building yesterday. They must have gotten worse! At 08:07 AM 6/30/99 -0700, Phil wrote: >Hi John, > I bought a Placer 400 some time back with plans to use it with my >remote gear for both location accuracy and time lock. I used it once on >a trip to the Geysers just for a location fix when I first got it to try >it out and it worked great. I have plans to tie it into my recorder for >time locking, but I've been busy and haven't gotten back to that >project. > I sort of remember that as long as the back up battery (the 9v one) >is good it is suppose to fire right up and remember where it was last >and the time should be fairly close so that it will update quickly.... >... what does your 1 second pulse look like on that pin. >Mine is a very short very low level differentiated pulse or spike like >looking thing.... * John C. and Jan H. Lahr * * JohnJan@........ * * 1925 Foothills Road * * Golden, Colorado 80401-1718 * * (303) 215-9913 * * http://lahr.org/john-jan * * AOL version of homepage: * * http://lahr.org/john-jan/homepage.html * * http://giseis.alaska.edu/lahr * _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Placer 400 problems From: "Kevin J. Rowett" krowett@.......... Date: Wed, 30 Jun 1999 09:24:43 -0700 > > >Some time ago I looked at pin 9 on the scope. There was a very short >spike every second. I was hoping to be able to count up perhaps >15 minutes of spikes and then put out a 15 minute mark (trace offset) >on my digital record. This would give me a clock correction every >15 minutes. The problem is that I don't know how to build such >a circuit. Any ideas out there? It's a 1 pulse per second output, sync'ed to GPS time. (1PPS). 15 minutes is 900 counts at a frequency of 1Hz. A 10 bit counter, with a bit of logic to reset at 899 would be the ticket. KR _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Using Lasers From: John Taber taber@............. Date: Thu, 1 Jul 1999 11:59:01 +1200 (NZST) Denny, There is a group here in New Zealand that has a fancy ring laser in an old WWII bomb shelter. They have shown that it is capable of recording seismically generated rotations. It's not the sort of laser you could build at home and the papers that they list are rather technical but there are some good pictures of the laser and the "cave". Their main web site is http://www.phys.canterbury.ac.nz/~physges/ Cheers, John Denny Goodwin wrote: > > Anyone using lasers for detection - if so, how? > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Old PC Convertible - can it be upgraded? From: Steve Hammond shammon1@............. Date: Thu, 01 Jul 1999 04:26:30 -0700 Hi Ted, take it... I seem to remember the one at the meeting could also run off of a battery pack. Let's just talk about the standard PC Convertible. It is a PC XT with a mono CGA display in it and standard XT keyboard. You can put 1.44's in it, however you need set144 from the PC tools disk to make it work. Fr4om a HDD standpoint, you could put in an a small 20Meg MFM drive and controller card. Come see me and I'll fix you up. BTW, I have one already setup like this and another one on for parts. Workes fine with an DACA card and you can collect samples at 60SPS. The other thing you can do is go to fry's and buy a small footprint motherboard. It will need to have the old style P8-P9 power connectors however and support CGA. Regards, Steve PSN San Jose Ted Blank wrote: > > I have a friend who will give me an old PC Convertible (or "luggable" as > we used to call it). I remember someone at the last PSN meeting had one > which was customized for portable quake recording. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Old PC Luggable From: Phil Giannini pgiannini@........ Date: Thu, 01 Jul 1999 07:33:51 -0700 Hi Again Guys, FYI...... If you are looking for neat old stuff like that "Luggable", CHEAP mother boards, and just lots of real cool stuff that tinkers like us are always messing around with, Mike Quinn's Electronics in San Leandero is the place to go. It is a tinkers paradise. The place is just of 98th Ave. on the southwest side of the 880. Jay, the guy who runs the place, is helpful, very knowledgeable, and his prices are right. Regards, Phil _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Placer 400 problems From: Phil Giannini pgiannini@........ Date: Thu, 01 Jul 1999 08:34:09 -0700 Hi again John and All, Yes, the Placer 400 runs nicely from 12 vdc. It was originally designed to be used in commercial vehicles to track their locations, so it's a happy guy on 12 volts. I used the GPSSK software to get a readout of my location and a time setting when I used it at the Geysers. But, I didn't have my recorder locked to it because my system is currently setup to do WWV tone lock. I did use the time reading from the Placer though to set the computer clock as I couldn't pickup WWV where I was. Now don't hold me to this, but I don't think you will need the GPSSK software running if you are just going to be using the Placer 400 for time lock once the receiver is locked up. Reason being, I'm almost positive that the 1 second pulse comes out even without that software running. I do think, however, that you will have to clean up the 1 second pulse some though before you can use it to trigger a counter or other digital circuitry properly. Especially now that I hear your 1 second signal is kind of crummy looking too. Phil _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Placer 400 problems From: "James M Hannon" jmhannon@............................ Date: Thu, 1 Jul 1999 10:43:11 -0500 John, Your description of the 1 PPS signal (small amplitude and bipolar) sounds like you are either looking at to wrong pin or there is a broken wire somewhere. I see this sort of signal when probing with a scope and happen to be looking at an adjacent wire that is not connected to anything. The capacitance between the wires will cause you to see a signal that looks like what you described. The 1 PPS signal is typically a pulse just a few microseconds in duration but should not be bipolar. A bad scope probe will also cause the pulse to look bad. Jim Hannon _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Placer 400 problems From: John Lahr lahr@................... Date: Thu, 1 Jul 1999 12:53:56 -0600 (MDT) Hi Phil, When you used GPPSK to get the time, was it very accurate? I think it only redisplays the time every few seconds, although it might be possible to speed this up. Kevin suggested using a 10 bit counter and some logic elements to get a 15 minute pulse. Can anyone recommend a book that would show how to design such a circuit? Or, does anyone have a similar circuit that would only need minor modifications? Thanks, JCLahr _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Golden PSN Meeting From: The Lahrs JohnJan@........ Date: Thu, 01 Jul 1999 22:30:45 -0600 After the PSN meeting here in Golden, I found a plastic cap that could have come off of one of the show-and-tell items at my house. The cap is 1.5" in diameter and 0.5" high. There is a 2mm diameter hole in the center and the outside rim has 6 vertical bumps. The bottom surface is skuffed, so this may have formed the base of one leg of an instrument. John * John C. and Jan H. Lahr * * JohnJan@........ * * 1925 Foothills Road * * Golden, Colorado 80401-1718 * * (303) 215-9913 * * http://lahr.org/john-jan * * AOL version of homepage: * * http://lahr.org/john-jan/homepage.html * * http://giseis.alaska.edu/lahr * _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: 15-minute counter for Placer 400 From: The Lahrs JohnJan@........ Date: Fri, 02 Jul 1999 04:38:58 -0600 Kevin, That would be great! I'm not in a big hurry, as I'm dealing with a herniated disk right now and probably will not get my seismic system set up again for another month or so. My plan is to continue using a one-channel AD (DaTaq) which is fed by coil/magnet/amplifier from my home-built Lehman. DaTaq stamps the files with the computer time. I would like to offset the trace every fifteen minutes for about 10 seconds. To do this I'll add a summing amplifier after the final stage of the amplifier. Once I get the phase of the fifteen-minute marks correct, they will be used to derive four clock corrections per hour. Thinking about it now, it may be tricky getting the fifteen-minute marks to go off on the minute. One option would be have a push button that would set the counter to 899 and block the ticks from the GPS unit when it is held down. The button could be released just before the 0-, 15-, 30-, or 45-minute mark to set the phase of the ticks. Thanks for this offer! Of course I'll reimburse you for the parts, and post the schematic when it's working in case anyone else wants to try a similar scheme. John, How big of a hurry are you in? What kind of output do you need the 15 minute pulse to be? What is it going into? I'll breadboard a circuit and send it to you, but, it will be a couple of weeks before I can get it into the mail. KR >Kevin suggested using a 10 bit counter and some logic >elements to get a 15 minute pulse. Can anyone recommend >a book that would show how to design such a circuit? Or, >does anyone have a similar circuit that would only need >minor modifications? * John C. and Jan H. Lahr * * JohnJan@........ * * 1925 Foothills Road * * Golden, Colorado 80401-1718 * * (303) 215-9913 * * http://lahr.org/john-jan * * AOL version of homepage: * * http://lahr.org/john-jan/homepage.html * * http://giseis.alaska.edu/lahr * _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Placer 400 problems - a counter circuit suggestion From: "Charles R. Patton" patton@.......... Date: Fri, 02 Jul 1999 09:44:20 -0700 Hi, If you go to the Texas Instruments site: http://www.ti.com/sc/docs/products/logic/cd4059a.html you will find the spec sheet for a CD4059A, a 16 bit, programmable divider IC. This will make it extremely simple to do your divide by any number from 3 to 15,999. Mouser Electronics is selling them for $3.58. Just add 16 bits worth of DIP switches together with pull-ups, one button for preset (reset to zero) and you are done. Since it is a CD part, you can run it on anything from 3 to 15V. Take a look at the spec sheet, and if you still have a problem, send me a note, and I=92ll draw u= p a schematic and post it. Charles R. Patton P.S., I=92m posting from work, so if you want to direct email, the addres= s below will work better over the weekend. charles.r.patton@........ _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Old PC Convert From: Ted Blank tblank@.......... Date: Fri, 2 Jul 1999 11:20:18 -0700 (PDT) Hey Phil, you did a hell of a job. But wouldn't it have been easier to just move the handle from the luggable over that PC where you got all the parts? :-) IF you have any info on the power supply mods, can you send it? Thanks. Ted Blank San Jose, California On Tue, 29 Jun 1999, Phil Giannini wrote: > Hi Ted and Gang, > I was the one with the converted luggable. But I cheated and > completely gutted the machine and installed a 386 DX40 mother board, 9 > inch B/W VGA monitor, 500 meg hard drive, 1.44 floppy, and still had > room to build in one of Larry's demod boards. I also modified the power > supply to work on AC or from 12VDC so it could be operated in remote > locations from a 12v car battery when no AC power is available. An AT > type keyboard was modified to fit in the luggable's fold down > door/bottom, as the luggable originally used an XT type keyboard that > wouldn't work on the 386 mother board. > The system is using the PC Labs 12 bit A/D board modified for time > lock running Larry's SDR software and Winquake. There is also a 33.6 > modem on board so I can upload any captured events if there is a phone > line available at the remote location. > > On another note, I noticed that the station names on the list for > me are incorrect. I don't know if that is just a typo or if they are > actually listed that way. If so can they be corrected? They should be > SFN and SFZ, and I would like to reserve SFE for the partly finished E/W > sensor I am building. Also the TVZ listing can be removed from the list > as that system has been retired. Thanks and sorry for any inconvenience > that may have created. > > > Regards, Phil > > SFN & SFZ > > > _____________________________________________________________________ > > 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) Subject: Packrat humor in a garage clean out endeavor... From: meredith lamb psnseismograph52@.......... Date: Fri, 02 Jul 1999 15:43:29 -0600 Hi all, I've been trying to clean up my garage for awhile; in the course of this trauma, humor springs forth, and I thought you might need this inspiration, from my brother and sister..... "Joan R." wrote: > Hi guys, > > Can hardly believe it's July 1 already. Or, as the saying goes, "Time > flies like an arrow and fruit flies like bananas." > > There are rules to successful trashing, Meredith. The basic rule is, if > you've had stuff stored for 10 years, and you haven't gotten around to > using it, then odds are you never will, so pitch it. Trashing is best when > you're really angry about something or at someone. If you're relaxed and > feeling all sentimental, you tend to want to hang onto stuff or > optimistically think there's still a use for or a way to fix that broken > appliance or furniture. Pressure helps. Like, if you're expecting a fire > hazard inspector. It's helpful if you have one or more do-it-yourselfer > friends. They always can see possibilities in your junk, covet it, and are > thrilled when you give it to them. It helps if you make them think you're > doing it out of the goodness of your heart. Don't build shelves or buy > storage bins or cabinets. That just encourages clutter, because true trash > collectors never get around to sorting and putting stuff away. If you sort > stuff and put them away, you'll never be able to find something when or if > you actually want it, and you'll wind up buying more stuff. Don't quit > when you get tired. You throw out more when you get too tired to think if > you really want to keep it. >From Bob Lamb; "Hi Joan & Meredtih...will the trashing ever stop? Actually I do believe and follow your philosofee (ha) Joan, and do OK up to a certain point.... the targeted trash object can be in my hand ready to be tossed out... but I freeze up, can't let go of it...fingers holding tight!!! (and) Now I'am curious..have you tossed something out, but then changed your mind and retrieved it??" Perhaps the most traumatizing potential Rule 1 is: Throw out the top 10 most coveted piles....then the rest will come much easier. Trouble is....the best isn't the usual humdrum homey type stuff, if you're a typical experimenter....but, if nobody else knows that; you maybe looked upon as being courageous is you do trash out the homey stuff....first. I think I'll be courageous. Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Distant quake coming... From: meredith lamb psnseismograph52@.......... Date: Fri, 02 Jul 1999 19:51:00 -0600 Hi all, Looks like a distant quake coming in....about 01:47 p wave utc. iP. Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Distant quake coming in... From: meredith lamb psnseismograph52@.......... Date: Fri, 02 Jul 1999 19:54:04 -0600 Hi all, Fair size L waves coming 01:51 utc. approximately. This looks like it will take some time to die down. Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Distant quake coming... From: barry lotz gbl@....... Date: Fri, 02 Jul 1999 19:01:30 -0700 Meredith Picking it up strong here Barry meredith lamb wrote: > Hi all, > > Looks like a distant quake coming in....about 01:47 p wave > utc. iP. > > Meredith Lamb > > _____________________________________________________________________ > > 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) Subject: Re: Distant quake coming in... From: david alexander dalex@........... Date: Fri, 02 Jul 1999 19:02:39 -0700 don't have any instruments here but the seat of my pants says it was in the north puget sound area. maybe an aftershock of the vancouver island quake of this morning. dave meredith lamb wrote: > > Hi all, > > Fair size L waves coming 01:51 utc. approximately. > > This looks like it will take some time to die down. > > Meredith Lamb > > _____________________________________________________________________ > > 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) Subject: Distant quake coming in... From: meredith lamb psnseismograph52@.......... Date: Fri, 02 Jul 1999 20:04:12 -0600 Barry, Perhaps, a aftershock of the Vancouver Island quake of earlier on the 2nd? Red Puma has nothing yet. If its strong there and so-so here, perhaps it is around Vancouver? Could be any where of course. Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Distant quake coming in... From: barry lotz gbl@....... Date: Fri, 02 Jul 1999 19:14:00 -0700 I'll get it from SDR, get distance and see if we can triangulate Barry meredith lamb wrote: > Barry, > > Perhaps, a aftershock of the Vancouver Island quake of earlier > on the 2nd? Red Puma has nothing yet. If its strong there and > so-so here, perhaps it is around Vancouver? Could be any > where of course. > > Meredith Lamb > > _____________________________________________________________________ > > 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) Subject: Re: Distant quake coming in... From: meredith lamb psnseismograph52@.......... Date: Fri, 02 Jul 1999 20:07:27 -0600 david alexander wrote: > don't have any instruments here but the seat of my pants says it was in > the north puget sound area. maybe an aftershock of the vancouver island > quake of this morning. > dave David, Where are you....in the Northwest perhaps....feel anything? Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Distant quake coming in... From: david alexander dalex@........... Date: Fri, 02 Jul 1999 19:09:08 -0700 this from the univ of washington site. Time of Occurrence (GMT): Saturday July 3, 1999 at 01:43:54.36 Z Depth (km) 39.87 Magnitude (Mc) 3.5 Location 47.0638N 123.4682W 6.8 km N of Satsop, WA dave.. meredith lamb wrote: > > Barry, > > Perhaps, a aftershock of the Vancouver Island quake of earlier > on the 2nd? Red Puma has nothing yet. If its strong there and > so-so here, perhaps it is around Vancouver? Could be any > where of course. > > Meredith Lamb > > _____________________________________________________________________ > > 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) Subject: Distant quake coming in... From: meredith lamb psnseismograph52@.......... Date: Fri, 02 Jul 1999 20:19:42 -0600 Barry and David, Red Puma has 3 close locations...Washington/Van Courver/ British Columbia. Tentative mag 5.6. Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Distant quake coming in... From: barry lotz gbl@....... Date: Fri, 02 Jul 1999 19:38:39 -0700 Meredith It seem like it's south of vancouver Isl I read it at 1050k where vancouver Isl was about 1300k from me. Barry meredith lamb wrote: > Barry and David, > > Red Puma has 3 close locations...Washington/Van Courver/ > British Columbia. Tentative mag 5.6. > > Meredith Lamb > > _____________________________________________________________________ > > 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) Subject: PNW EQ From: The Lahrs JohnJan@........ Date: Fri, 02 Jul 1999 20:35:38 -0600 The USGS NEIS has: 47.08 N -123.46 W 40.6 KM Mag 5.5 1999/07/03 01:43:54 From this page of seismograms http://aslwww.cr.usgs.gov/Seismic_Data/heli2.htm it was located only slightly closer to Albuquerque than to College, Alaska. John * John C. and Jan H. Lahr * * JohnJan@........ * * 1925 Foothills Road * * Golden, Colorado 80401-1718 * * (303) 215-9913 * * http://lahr.org/john-jan * * AOL version of homepage: * * http://lahr.org/john-jan/homepage.html * * http://giseis.alaska.edu/lahr * _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: EQ Alarm From: The Lahrs JohnJan@........ Date: Fri, 02 Jul 1999 20:45:22 -0600 My alarm and eq map of NEIS quakes on this page: http://geohazards.cr.usgs.gov/fingview/fingerview.html worked to alert me to the new location. If you use Netscape it should work right away. With MSIE you will need to download a file from the MS page before it will work. John * John C. and Jan H. Lahr * * JohnJan@........ * * 1925 Foothills Road * * Golden, Colorado 80401-1718 * * (303) 215-9913 * * http://lahr.org/john-jan * * AOL version of homepage: * * http://lahr.org/john-jan/homepage.html * * http://giseis.alaska.edu/lahr * _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Wow! John Lahr....that Viewer is great! From: meredith lamb psnseismograph52@.......... Date: Fri, 02 Jul 1999 21:13:29 -0600 John, Looks like I'll have to reference your Recent Seismicity Viewer from now on. Perhaps it will be faster than Red Puma. I didn't know this even existed before. I note it was overwhelmed at the web site after your notice.....got down to 0 to 47 bytes per second....but it eventually all came through. Hope your herniated disk can be corrected sometime with little down time. Wonder if Edward Cranswick is going to Washington for this quake series? Interesting communication on this quake....it seems there is a number of people checking PSN, and participating...nice. Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: PNW EQ From: barry lotz gbl@....... Date: Fri, 02 Jul 1999 20:21:06 -0700 John Your note brings up an interesting question. Are, or should, the recordings normalized or at the same gain? If they were then one could make a better determination of the event general location. Barry The Lahrs wrote: > > >From this page of seismograms > > http://aslwww.cr.usgs.gov/Seismic_Data/heli2.htm > > it was located only slightly closer to Albuquerque than > to College, Alaska. > > John > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: PNW EQ From: The Lahrs JohnJan@........ Date: Fri, 02 Jul 1999 21:40:56 -0600 Barry, On the Albuquerque all of the seismograms have the same gain, at least it looked that way to me on a quick glance. The gain is specified along the lower edge of each record as 3000 @ .02 Hz. Meredith, Red Puma will generally be the first site with some preliminary information. I'm just plotting the reviewed NEIS solutions that are put out on the finger listing. I noticed tonight that the alarm range twice when there was not an new earthquake added. This may be due to one of the eq solutions being modified, so the parameters have changed in some way. I'm still looking into this. John * John C. and Jan H. Lahr * * JohnJan@........ * * 1925 Foothills Road * * Golden, Colorado 80401-1718 * * (303) 215-9913 * * http://lahr.org/john-jan * * AOL version of homepage: * * http://lahr.org/john-jan/homepage.html * * http://giseis.alaska.edu/lahr * _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: sound picture? From: "Bonnie Schafer" bschafer@......... Date: Fri, 2 Jul 1999 21:09:28 -0700 Hi, was wondering if there is any way I might set up a sound signal that would set off some kind of audible alarm when there is a quake occurring? I would need to do this as I can't see the charts and seismograms and such. I thought of trying to find a seismometer but don't know where to look or how to go about making one. Also, would have to find a place to set it up where there isn't so much vibration. I live near the freeway and trucks and cars are always vibrating the house--funny birds can tell the difference. When it is dark and we have a quake I have to get up and calm them down yet when a truck or car goes by they don't take notice of them. Bonnie the crafty crafter _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: GPS's From: Karl Cunningham karlc@....... Date: Sat, 03 Jul 1999 00:21:35 -0700 Greetings -- The San Diego Museum of Natural History is interested in buying a GPS for timing for their seismometer, which will be running SDR. The GPS must accomodate an external active antenna that can be located on the roof, at then end of about 150 feet of cable. Of course, cost is a factor too. Does anyone have any recommendations on a GPS I could suggest to the museum? Karl Cunningham La Mesa, CA. PSN Station #40 karlc@....... _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: EQ Alarm down now! From: The Lahrs JohnJan@........ Date: Sat, 03 Jul 1999 03:54:58 -0600 I just noticed that the alarm is not working and when I checked at work the critical computer has apparently crashed! I'm not sure how soon someone will get it going again, so for now my alarm and plotting programs will not work! ******** The alarm and eq map of NEIS quakes on this page: http://geohazards.cr.usgs.gov/fingview/fingerview.html worked to alert me to the new location. If you use Netscape it should work right away. With MSIE you will need to download a file from the MS page before it will work. John John C. Lahr POB 1529 Golden, CO 80402 (303) 215-9913 http://lahr.org/john-jan I am only one But still I am one. I cannot do everything and because I cannot do everything I will not refuse to do the something that I can do. Edward Everette Hale _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: sound picture? From: The Lahrs JohnJan@........ Date: Sat, 03 Jul 1999 04:06:24 -0600 Hi Bonnie, How do you "read" the PSN postings? Do you use a translator from text to voice? The browser-based alarm I mentioned earlier would notify you of new earthquakes on the NEIS finger listing, which is on the NEIS web site here: http://wwwneic.cr.usgs.gov/neis/bulletin/bulletin.html The alarm has a graphical interface requiring a mouse click to reset it after an earthquake, so that may be a problem. Also, it would go off for any reviewed solution anywhere in the world! Another option would be to set up a seismic system using Larry's AD board and software. You could use a 4.5 Hz geophone for detecting local events. I haven't used his program, so don't know for sure if you could set up the trigger settings to alarm on a local earthquake but not a bus. Birds may be smarter! Also, Larry can let you know if the system has an audible alarm. Sounds like an interesting project. John At 09:09 PM 7/2/99 -0700, you wrote: >Hi, was wondering if there is any way I might set up a sound signal that >would set off some kind of audible alarm when there is a quake occurring? > >Bonnie the crafty crafter * John C. and Jan H. Lahr * * JohnJan@........ * * 1925 Foothills Road * * Golden, Colorado 80401-1718 * * (303) 215-9913 * * http://lahr.org/john-jan * * AOL version of homepage: * * http://lahr.org/john-jan/homepage.html * * http://giseis.alaska.edu/lahr * _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Satsop/Aberdeen WA EQ From: SW6079@....... Date: Sat, 3 Jul 1999 09:38:31 EDT Got a great record on it here in Bothell. If anyone would like it, e-mail me at sw6079@ aol.com _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: GPS's From: "Rex Klopfenstein, Jr." rklopfen@......... Date: Sat, 03 Jul 1999 10:00:29 -0400 Look at Larry's suggested GPS system on his website. I would guess that it costs about $200 total for parts. Does require some assembly! Karl Cunningham wrote: > Greetings -- > > The San Diego Museum of Natural History is interested in buying a GPS for > timing for their seismometer, which will be running SDR. > > The GPS must accomodate an external active antenna that can be located on > the roof, at then end of about 150 feet of cable. Of course, cost is a > factor too. > > Does anyone have any recommendations on a GPS I could suggest to the museum? > > 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 -- Rex Klopfenstein, Jr. Bowling Green, OH rklopfen@......... www.wcnet.org/~rklopfen _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: GPS's From: "Rex Klopfenstein, Jr." rklopfen@......... Date: Sat, 03 Jul 1999 10:00:29 -0400 Look at Larry's suggested GPS system on his website. I would guess that it costs about $200 total for parts. Does require some assembly! Karl Cunningham wrote: > Greetings -- > > The San Diego Museum of Natural History is interested in buying a GPS for > timing for their seismometer, which will be running SDR. > > The GPS must accomodate an external active antenna that can be located on > the roof, at then end of about 150 feet of cable. Of course, cost is a > factor too. > > Does anyone have any recommendations on a GPS I could suggest to the museum? > > 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 -- Rex Klopfenstein, Jr. Bowling Green, OH rklopfen@......... www.wcnet.org/~rklopfen _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: sound picture? From: "Bonnie Schafer" bschafer@......... Date: Sat, 3 Jul 1999 08:04:42 -0700 Hi, thank you so much for writing. I really appreciate it. I use a speech synthesizer that hooks to my computer--mine is an internal one--a card that goes inside the PC. Anyway, it will read text just fine but does not read graphics at all. What I am looking for--and there probably isn't such a thing--but an alarm to sound at the time of a quake occurring and then text to appear telling me in plain text where the quake occurred and the epicenter and magnitude of the event. I suspect that there isn't such a thing but it sure would be interesting. I thought of getting a seismometer but don't know where I would put it as this mobile home vibrates all the time from trucks and cars from the freeway. Again, thanks so much for writing. By the way, if you have any more questions please don't hesitate to ask I don't mind at all and would be glad to answer any questions you may have. I Bonnie the crafty crafter _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: GPS's From: barry lotz gbl@....... Date: Sat, 03 Jul 1999 09:06:14 -0700 Hi Karl It's not a GPS and it requires a small circuit but I have been using the Radio Shack clock with SDR for awhile and it works well (~$40). I have the antenna at the end of a 30' cable to locate it in an area of good reception. Barry Karl Cunningham wrote: > Greetings -- > > The San Diego Museum of Natural History is interested in buying a GPS for > timing for their seismometer, which will be running SDR. > > The GPS must accomodate an external active antenna that can be located on > the roof, at then end of about 150 feet of cable. Of course, cost is a > factor too. > > Does anyone have any recommendations on a GPS I could suggest to the museum? > > Karl Cunningham > La Mesa, CA. > PSN Station #40 > karlc@....... > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: sound picture? From: The Lahrs JohnJan@........ Date: Sat, 03 Jul 1999 12:19:24 -0600 Bonnie, Do you use a PC? Is it possible to use a DOS window? If you install java on a PC, then I could write a simple program that would periodically check for new events in California and sound an alarm if one is reported. Then you could listen to the file of recent events to get the coordinates, time and location. The file format would be like this, which is the "finger" format. These are the last two events reported by Caltech. 99/07/03 00:20:15 33.96N 116.82W 18.5 2.3ML A 4 mi. NE of Banning, CA 99/07/03 01:26:47 37.18N 118.40W 5.5 3.0ML C 7 mi. W of Big Pine, CA At 08:04 AM 7/3/99 -0700, Bonnie wrote: What I am looking for--and there >probably isn't such a thing--but an alarm to sound at the time of a quake >occurring and then text to appear telling me in plain text where the quake >occurred and the epicenter and magnitude of the event. * John C. and Jan H. Lahr * * JohnJan@........ * * 1925 Foothills Road * * Golden, Colorado 80401-1718 * * (303) 215-9913 * * http://lahr.org/john-jan * * AOL version of homepage: * * http://lahr.org/john-jan/homepage.html * * http://giseis.alaska.edu/lahr * _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: sound picture? From: "Bonnie Schafer" bschafer@......... Date: Sat, 3 Jul 1999 21:06:29 -0700 Hi, I have a Pentium 133 running Windows '95 hopefully to be upgraded to '98 and I am using a speech program called Jaws--Job Access With Speech. Anyway, according to what I have been told Jaws will read Java language and it can also handle a Dos Window. I am going to try and find out a little more about this as I will be attending the American Council of the Blind convention in L.A. The people who wrote Jaws will be there and I will pose these questions to them. So, as far as I know there shouldn't be a problem with this. I know that in the earlier versions of Jaws there were some difficulties reading Java but that has been fixed I am told. I would love a program like this and can read the Cal Tech reports just fine. Let me know how much you would want for doing this. It is very much appreciated. If you have any further questions please feel free to ask me. Thanks. Bonnie the crafty crafter _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: GPS's - GPS Timing System Announcement From: Larry Cochrane cochrane@.............. Date: Sat, 03 Jul 1999 23:13:57 -0700 Hi Karl, Good timing for your message. I just finished a web page documenting the GPS timing system I will be offering. The web page URL is http://www.seismicnet.com/gps/. There you will find photos and some documentation on the system, as well as the cost. The antenna I have is not weather proof and only has 10 feet of cable. I'm not sure if it can drive 150 feet of cable with having 26 db of gain. One thing you can do is place the receiver near the antenna and run a long RS-232 cable. The baud rate between SDR and the GPS receiver is 9600. You should be able to run a 3 wire shielded cable that long. All you need is transmit, receive and 1 PPS lines + ground. You will need to power the receiver using a power supply near it. The unit takes 7 to 40 vdc at a 250ma to power it. Maybe you could run a 4th wire for power. As long as theres more then 7 volts at 250 ma at the other end, it should power the unit just fine. For the interface board I ended up laying out my own board. There were a few things I didn't like about the TAPR board, and, I thought it would be a good board too try and layout myself. Being a simple board I thought I would try out my hand at laying out a PC board. My brother laid out all of my other boards. I used a program called WinBoard. I'm not very happy with it. It constantly crashed or locked up but I finally made a board I was happy with. All in all it turned out pretty good. So far I have 4 units going to Italy and maybe 6 units to Portugal. I bought 10 GPS receivers and had 15 blank interface cards made. The problem is I haven't heard from my contact in Portugal and can't get a PO number and shipping address. So if I don't here from him in a few days I would like to sell the receivers I have ASAP since the cost is on my credit card. -Larry Cochrane Redwood City, PSN At 12:21 AM 7/3/99 -0700, you wrote: >Greetings -- > >The San Diego Museum of Natural History is interested in buying a GPS for >timing for their seismometer, which will be running SDR. > >The GPS must accomodate an external active antenna that can be located on >the roof, at then end of about 150 feet of cable. Of course, cost is a >factor too. > >Does anyone have any recommendations on a GPS I could suggest to the museum? > > >Karl Cunningham >La Mesa, CA. >PSN Station #40 >karlc@....... _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: sound picture? From: The Lahrs JohnJan@........ Date: Sun, 04 Jul 1999 05:42:53 -0600 Hi Bonnie, You can test if you have java installed by going to a DOS window and typing the command: java If it's installed the response will be a number of lines starting with the line: Usage: JAVA.EXE [-options] class [args...] If it's not installed, then the response will be: Bad command or file name I could give you a .zip file with java and my small program files included, but all you would need is the small program files if you already have java installed on your PC. The .zip file that includes java is 11.9 MB. The program I'm working on will wake up every 5 minutes and check if the Caltech earthquake listing file has been changed. If it has, then the computer bell will sound every five seconds for 5 minutes. There will be a file on your disk named neweqs.fin with a listing of the new earthquakes. If you're away from the computer for more than 5 minutes, you can just check the file neweqs.fin to see if you've missed an alarm. How does this sound? I just noticed one slight problem. Sometimes the Caltech event file is changed because an earthquake more than 7 days old has been dropped from the current listing. In this case, the alarm sounds but the file neweqs.fin contains the oldest event in the new listing rather than a very recent event. John At 09:06 PM 7/3/99 -0700, you wrote: >Hi, I have a Pentium 133 running Windows '95 hopefully to be upgraded to '98 >and I am using a speech program called Jaws--Job Access With Speech. >Anyway, according to what I have been told Jaws will read Java language and >it can also handle a Dos Window. John C. Lahr POB 1529 Golden, CO 80402 (303) 215-9913 http://lahr.org/john-jan I am only one But still I am one. I cannot do everything and because I cannot do everything I will not refuse to do the something that I can do. Edward Everette Hale _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Computer card From: Arie Verveer ajbv@............ Date: Sun, 04 Jul 1999 20:33:32 +0800 Hi, I thinking of buying a Y2K card that fits in the ISA slot of my old 486 computer. It sounds quick and easy fix. Has anyone had any experience with this type of card. All the computer runs is Win95 (networked) and Larry's program SDR. Arie See: http://www.mgram.com.au _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Seismograph From: Marchal van Lare vanlare@.............. Date: Sun, 4 Jul 1999 09:25:57 -0400 Hi all, One year ago I started recording earthquakes with three 4.5 Hz = Mark Products geophones. These geophones are only sensitive to = local earthquake activity. = The problem is, I am missing the large distant earthquakes. To be able to detect the larger distant events I will need a long period seismograph. I tried to build my own device several times, but without good results. My question is, do anyone know of any source where I can buy a good working seismograph or parts? Perhaps someone who is willing to = build one for me? = I am looking forward to hear from you. Best regards, Marchal van Lare -Nieuwvliet, The Netherlands _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: sound picture? From: "Bonnie Schafer" bschafer@......... Date: Sun, 4 Jul 1999 06:59:10 -0700 Hi, first of all, I would like to apologize to the list for all of this but I can't get the address to come up privately when I use the reply to author command in my email program. Anyway, I went to a Dos Window and tried it and got the "bad command or file name." However, I did see a Java folder under Windows and it has some stuff in it. Should I try and install it from that directory? Sorry, my old Dos is showing? Thanks. By the way, your program sounds like it is just what I am looking for. Bonnie the crafty crafter _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: sound picture? From: The Lahrs JohnJan@........ Date: Sun, 04 Jul 1999 08:30:04 -0600 Bonnie, Check if you have a file named java.exe in a bin directory beneath your java directory. That's one of the critical files, among many others, for running a java program. Also, I forgot to mention, when you run this program you need to be logged onto the internet, as it goes out via the internet every 5 minutes to get the latest listing of events from Caltech. If you find java.exe, let me know what directory it is in and what the sister directories next to it are. I'm not too worried about the noise on the PSN list, as someone else might also decide to do this and the archive will then include this discussion. John At 06:59 AM 7/4/99 -0700, you wrote: >I did see a Java folder under Windows and it has some stuff >in it. * John C. and Jan H. Lahr * * JohnJan@........ * * 1925 Foothills Road * * Golden, Colorado 80401-1718 * * (303) 215-9913 * * http://lahr.org/john-jan * * AOL version of homepage: * * http://lahr.org/john-jan/homepage.html * * http://giseis.alaska.edu/lahr * _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Seismograph From: meredith lamb psnseismograph52@.......... Date: Sun, 04 Jul 1999 10:14:09 -0600 Marchal van Lare wrote: > Hi all, > > One year ago I started recording earthquakes with three 4.5 Hz > Mark Products geophones. These geophones are only sensitive to > local earthquake activity. > > The problem is, I am missing the large distant earthquakes. > To be able to detect the larger distant events I will need > a long period seismograph. > > I tried to build my own device several times, but without good > results. Marchal, Scavenger that I am, I am wondering if perhaps, your design/s, maybe perhaps lacking in success due to perhaps one or two parts.....usually the pivot or sensor/magnet, if its a horizontal? Maybe the best approach is to give a description of what you have now, and any kind of rough measured results....this could give us a clue perhaps. Not to be overlooked is potentially the problem of your pier, what with the likely hood of your soft soils creating problems? > > > My question is, do anyone know of any source where I can buy a good > working seismograph or parts? Perhaps someone who is willing to > build one for me? > > Right off the bat, if you can afford the cost, Larry has a variety of material on his web site. Mechanically, I kind of like the S-G variety, it doesn't present as much difficulty as say the normal "garden gate seismometer". Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Updated Webpage From: "Rex Klopfenstein, Jr." rklopfen@......... Date: Sun, 04 Jul 1999 13:44:23 -0400 I have just posted my siesmograms from the Vancouver and Washington quakes that occured on the 7/2 and 7/3. I also have posted a siesmogram from the quake near Iwo Jima - Bonin Island. I really don't see anything except noise in all plots except my high freq N/S. WinQuake picks an arrival time of about 5:43 UTC which is close to Bloomington Ind (BLO) site which is about 150 miles west of my site. At the pick point I do see a slight increase in activity. I don't now if I am seeing noise or an actual event! -- Rex Klopfenstein, Jr. Bowling Green, OH rklopfen@......... www.wcnet.org/~rklopfen _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Seismograph From: Marchal van Lare vanlare@.............. Date: Sun, 4 Jul 1999 14:52:40 -0400 Hi, My Lehman looks much like the one described in the Scientific American article. = The main frame doesn't consist of pipes, but I used metal bars = instead. The piano wire is directly attached to the upper main = frame. I didn't use a turnbuckle. The boom is a curtain rod of ~ 75 centimeters long. The problem is, I can't get the boom in a center position. I didn't get much farther. Perhaps the soft soil I live on (clay and sand) causes = the boom proble,? Meredith, you say the SG sensor isn't that much of a problem to build, even for someone who has problems with the simple 'Lehman'? :) Best regards, Marchal van Lare -Nieuwvliet, The Netherlands _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Seismograph From: aheerfor@...... Date: Sun, 4 Jul 1999 21:04:30 +0200 > The piano wire is directly attached to the upper main frame. I didn't use a turnbuckle. .... The problem is, I can't get the boom in a center position. I didn't get much farther. Perhaps the soft soil I live on (clay and sand) causes the boom proble,? < No, the problem is the attachment of the wire to the upper main frame. The point of attachment has to be slightly displaced towards the wanted direction of the boom. Some kind of screw adjustment of this point is desirable, so that the period of oscillation around the center position can be adjusted to 20 seconds or similar. Regards, Anders _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Seismograph From: meredith lamb psnseismograph52@.......... Date: Sun, 04 Jul 1999 13:56:05 -0600 aheerfor@...... wrote: > > > > The piano wire is directly attached to the upper main > frame. I didn't use a turnbuckle. > ... > The problem > is, I can't get the boom in a center position. I didn't get much > farther. Perhaps the soft soil I live on (clay and sand) causes > the boom proble,? > < > > No, the problem is the attachment of the wire to the upper main frame. > The point of attachment has to be slightly displaced towards the wanted > direction of the boom. > > Some kind of screw adjustment of this point is desirable, so that the > period of oscillation around the center position can be adjusted to 20 > seconds or similar. > > Regards, Anders > Marchal and Anders, The above seems like a way to go. Marchal you could try drilling the bar through, inserting a bolt and nuts, drill through the bolt sideways, and reattach the boom wire. A shaft coupler could work also, but with the added advantage of being able to slide up or down the metal bar. Of course, adjusting the rear setscrew/s comes into play for period adjustments also. Marschal, if you can center now after repairs, what are you using for the amplifier, etc.? The curtain rod you use, is it solid? How much weight in the mass? (I've had problems with the boom/mass ratio with my S-G's) The key now if everything works right is your coil and magnet. Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Computer card From: Larry Cochrane cochrane@.............. Date: Mon, 05 Jul 1999 00:26:41 -0700 Arie, I bought a Y2K board a while back. I finally had some time to play around with it the other day. It seems to work fine. I tried it on a non Y2K complaint motherboard running SDR. After plug it in it fixed the date problem without interfering with SDR. The board I bought is made by American Megatrends Inc. It cost almost $60.00 USD, a little high for a very small board that only has 3 ICs on it. The board also has a set of jumpers to select the BIOS address. I just used the default setting of C800. -Larry Cochrane Redwood City, PSN At 08:33 PM 7/4/99 +0800, you wrote: >Hi, I thinking of buying a Y2K card that fits in the ISA slot of my old >486 computer. It sounds quick and easy fix. Has anyone had any >experience with this type of card. All the computer runs is Win95 >(networked) and Larry's program SDR. > >Arie > >See: http://www.mgram.com.au > > > >_____________________________________________________________________ > >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) Subject: Re: Seismograph From: Marchal van Lare vanlare@.............. Date: Mon, 5 Jul 1999 12:02:28 -0400 Hi All, I think my main frame looks very unstable, so I've decided = to start 'all over again'. I'm thinking of making the main frame of one big upright metal = bar (20-30 centimeters wide), not like the two upright pipes = from the article. I think this will improve the stability of the = device. What do you suggest, a aluminium frame or can any metal be used? How big should the base plate be? Any input will be appreciated, Best regards, Marchal van Lare -Nieuwvliet, The Netherlands _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Seismograph From: "Rex Klopfenstein, Jr." rklopfen@......... Date: Mon, 05 Jul 1999 12:19:08 -0400 You might want to try find some cast aluminum tool plate at a scrap yard. This material is cast aluminum with both faces ground flat. It is used by machine tool builders and comes in thickness from about 1/2" and up, there is also metric thickness. I would check with scrap yards that deal with machine tool shops and large manufacturers. I used this material for the base of my S-G Seismometer. It cost me about $20 USD for a piece 3/4" x 6" x 12", this included having it saw cut to size (I think the sheets are 4' x 8' from mill). Good Luck Marchal van Lare wrote: > Hi All, > > I think my main frame looks very unstable, so I've decided > to start 'all over again'. > > I'm thinking of making the main frame of one big upright metal > bar (20-30 centimeters wide), not like the two upright pipes > from the article. I think this will improve the stability of the > device. > > What do you suggest, a aluminium frame or can any metal be used? > How big should the base plate be? > > Any input will be appreciated, > > Best regards, > > Marchal van Lare > -Nieuwvliet, The Netherlands > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@.............. with the body of the > message: leave PSN-L -- Rex Klopfenstein, Jr. Bowling Green, OH rklopfen@......... www.wcnet.org/~rklopfen _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: New station on the map From: Larry Cochrane cochrane@.............. Date: Mon, 05 Jul 1999 14:46:14 -0700 All, Today I added a new station to the USA station map. Here is Rex Klopfenstein, Jr. station info: NAME: Rex Klopfenstein, Jr. E-MAIL ADDR: rklopfen@......... HOMEPAGE ADDR: http://www.wcnet.org/~rklopfen TOWN/CITY: Bowling Green STATE/PROV: Ohio COUNTRY: USA LAT/LONG: 41.367N 83.650W ELEVATION: 210 meters STATION CODE: PSBG0 PSBG1 (.hns) S-G Horizontal (North/South) High Frequency Output PSBG2 (.lns) S-G Horizontal (North/South) Low Frequency Output PSBG3 (.hew) S-G Horizontal (East/West) High Frequency Output PSBG4 (.lew) S-G Horizontal (East/West) Low Frequency Output Uses Larry Cochrane's S-G Board with WWV Time Sync Recorder: Computer (486/66) running DOS with SDR card GROUND TYPE: Glacial debris over bedrock. Located in middle of the old Black Swamp. -Larry Cochrane Redwood City, PSN _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: sound picture? From: Ted Blank tblank@.......... Date: Mon, 5 Jul 1999 16:29:57 -0700 (PDT) Bonnie, EMON can be set up to "beep" the PC speaker when it records a quake. You can specify to beep once, or continuously until you press a key (that is, a beep every 10 seconds). Ted Blank San Jose, California On Fri, 2 Jul 1999, Bonnie Schafer wrote: > Hi, was wondering if there is any way I might set up a sound signal that > would set off some kind of audible alarm when there is a quake occurring? I > would need to do this as I can't see the charts and seismograms and such. I > thought of trying to find a seismometer but don't know where to look or how > to go about making one. Also, would have to find a place to set it up where > there isn't so much vibration. I live near the freeway and trucks and cars > are always vibrating the house--funny birds can tell the difference. When > it is dark and we have a quake I have to get up and calm them down yet when > a truck or car goes by they don't take notice of them. > > 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 > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Seismograph From: meredith lamb psnseismograph52@.......... Date: Mon, 05 Jul 1999 21:50:38 -0600 Marchal van Lare wrote: > Hi All, > > I think my main frame looks very unstable, so I've decided > to start 'all over again'. > > I'm thinking of making the main frame of one big upright metal > bar (20-30 centimeters wide), not like the two upright pipes > from the article. I think this will improve the stability of the > device. Making the mast more massive will help, but it will likely still need bracing (say two bars running to the side of forward, allowing space for the boom movement) to prevent the mass from influencing the tilt. > > > What do you suggest, a aluminium frame or can any metal be used? > How big should the base plate be? For the seismometer you have, it should be thick enough to not bend from mass movement (braces on top or underneath are a help, if the thickness is like less than 1/2 inch/12.5cm). The length and width will likely be determined by your wallet. I don't exactly remember the original design but I think it could be roughly 1 foot/40cm wide by maybe 2&1/2 foot/90cm in length.....which is maybe roughly like the Lehman design. Aluminum is usually preferred over iron for its non-magnetic propertys and easier to work with. Again, basically whatever you can find or afford and/or fit into your design. The above is a rectangular design....but a triangle shape if available might be even better, especially for stability and the 3 setscrews you will need. Don't know what you use at the present for setscrews, but a fine thread makes adjustments quicker for tweaking. Overall, build it as strong or non-flexible as possible....you will have less mechanical stress tilt in the long run. Building a good stable seismometer is not a quick operation. The only seismometers I ever built are the S-G's I use....but lacking alot of mechanical metal working equipment, it took some 4 months to "find" the parts....but with an idea of longevity and stability. Aluminum where I live is not cheap ($1.00 a pound scrapyard) and the larger sizes are kind of rare...but suitable material is probably out there....one has to call/search for it. Building a seismometer IS a project for sure....but once you get it constructed and in operation, it all becomes worthwhile. Should the project bog down, you might even check area geophysical equipment outfits, or universitys or seismic stations for unused older equipment....who knows? The newer and smaller seismometers are rapidly replacing the older bigger stuff. Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re[2]: Seismograph From: angel rodriguez angel@............ Date: Tue, 6 Jul 1999 05:06:06 -0400 Hello Marchal, Monday, July 05, 1999, 12:02:28 PM, you wrote: MvL> Hi All, MvL> I think my main frame looks very unstable, so I've decided MvL> to start 'all over again'. MvL> I'm thinking of making the main frame of one big upright metal MvL> bar (20-30 centimeters wide), not like the two upright pipes MvL> from the article. I think this will improve the stability of the MvL> device. MvL> What do you suggest, a aluminium frame or can any metal be used? MvL> How big should the base plate be? MvL> Any input will be appreciated, MvL> Best regards, MvL> Marchal van Lare MvL> -Nieuwvliet, The Netherlands MvL> _____________________________________________________________________ MvL> Public Seismic Network Mailing List (PSN-L) MvL> To leave this list email listserver@.............. with the body of the MvL> message: leave PSN-L Hi, I have some pictures of my latest lehmann at http://www.barriles.com/gardengate/ Best regards, angel mailto:angel@............ _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Seismograph From: meredith lamb psnseismograph52@.......... Date: Tue, 06 Jul 1999 09:20:02 -0600 angel rodriguez wrote: > Hello Marchal, > > Monday, July 05, 1999, 12:02:28 PM, you wrote: > > MvL> Hi All, > > MvL> I think my main frame looks very unstable, so I've decided > MvL> to start 'all over again'. > > MvL> I'm thinking of making the main frame of one big upright metal > MvL> bar (20-30 centimeters wide), not like the two upright pipes > MvL> from the article. I think this will improve the stability of the > MvL> device. > > MvL> What do you suggest, a aluminium frame or can any metal be used? > MvL> How big should the base plate be? > > MvL> Any input will be appreciated, > > MvL> Best regards, > > MvL> Marchal van Lare > MvL> -Nieuwvliet, The Netherlands > > MvL> _____________________________________________________________________ > > MvL> Public Seismic Network Mailing List (PSN-L) > > MvL> To leave this list email listserver@.............. with the body of the > MvL> message: leave PSN-L > > Hi, > > I have some pictures of my latest lehmann at http://www.barriles.com/gardengate/ > > Best regards, > angel mailto:angel@............ > Hello Angel, Thanks for the picture reference to your seismometer again. I like the tension pivot variation you have, but I do have a question is the BW workmate piece made out of plastic? If so, is there any sign yet of pressure flow/deformation? Marschal, Another variation of the same tension pivot can be seen at: http://www.users.uswest.net/~psnseismograph52/page22.html Here, John Lahr used a solid round ring as part of the pivot. the only major difference between the two is that Angel can remove the boom and mast, whereas John's pivot is more involved to remove (but simpler overall, and probably much stronger). You haven't mentioned the pivot you use, but if it is like the original Lehman knife edge design, it can present problems....I'd recommend something like Angels or Johns pivot design. Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Seismograph From: Marchal van Lare vanlare@.............. Date: Tue, 6 Jul 1999 12:25:42 -0400 Hello Meredith, Angel and others, Thank you for your recommendations. Yes, I use the original Lehman knife edge design, since its quite unstable, I am gonna try to use Angel's version. Tomorrow I will check a local machine tool store, to find out if they have some surplus materials. I am thinking of a 20-30 cm wide frame, to get it as stable as possible. I will let you know more tomorrow. Thank you for your help. Best regards, Marchal van Lare _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Seismograph From: robert barns 75612.2635@.............. Date: Tue, 6 Jul 1999 14:59:44 -0400 Marchal, Try this to get the boom to stay in an equilibrium position (centered):= Attach a weight to a sewing thread. Use enough weight to make the thre= ad hang straight. Hold the thread so that it passes very close (or touching= ) to the upper attachment point of the wire (which goes to the end of the boom) and close to the pivot point (at the end of the boom). Adjust the tilt--this tilt is in the direction which raises or lowers the end of the boom. Adjust this tilt until the hanging string is about 1/4" away from the lower pivot point in the direction of the far end of t= he boom. = This should allow the boom to come to equilibrium somewhere near center= .. = The period of swing (observed without any damping) should be somewhere around 2 to 8 seconds. This is too short for good Lehman operation--you should try to get between 16 and 30 seconds. This is done by reducing th= e tilt to give less than the 1/4" above. The final distance will be roughl= y 1/16". = All this assumes a boom about 24" long. A shorter boom requires smaller distances. Soft soil should not be a problem if you have a solid base under the Lehman--for example, a 3 foot square of plywood at least 1/2" thick. If your magnet is on the boom, make sure that there is nothing magnetic= nearby which could be attracted by the magnet. A distance of 3 feet shou= ld be safe. = The base plate of my Lehman is 1/2" thick aluminum and I think that thi= s is stiff enough. You can see it on my web site at www.webspan.net/~bbarns It is made from 1/2" steel piipe just the Sc= i. Am. article. This site also has pictures of Nick Caporossi's Lehman--a neat, lighter= construction that works well. = Bob Barns _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: EQ Alarm up and running now. From: meredith lamb psnseismograph52@.......... Date: Tue, 06 Jul 1999 14:01:05 -0600 Hi all, for those of you at being able to check out John Lahr's USGS web site in the past few days; its up and running now. Meredith Lamb > ******** > The alarm and eq map of NEIS quakes on this page: > > http://geohazards.cr.usgs.gov/fingview/fingerview.html > > worked to alert me to the new location. If you use > Netscape it should work right away. With MSIE you will > need to download a file from the MS page before it will > work. > > John > > John C. Lahr > POB 1529 > Golden, CO 80402 > (303) 215-9913 > http://lahr.org/john-jan > > I am only one > But still I am one. > I cannot do everything > and because I cannot > do everything > I will not refuse > to do the something > that I can do. > Edward Everette Hale _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: eq alarm and map pages are down now From: John Lahr lahr@................... Date: Tue, 6 Jul 1999 16:35:59 -0600 (MDT) Hello all, The Sun computer on which I run the eq alarm and map java code crashed on the weekend and, although it's up again, is still not able to run my java code. The principal person who keeps that computer running is on annual leave, so it may be a while before the program is working again. JCLahr http://geohazards.cr.usgs.gov/fingview/fingerview.html _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: RE: Seismograph From: "The Brewers" mbrewer@...... Date: Tue, 6 Jul 1999 22:21:58 -0300 Marchal, I do not understand why you find the original Lehman knife edge unstable. I have two Lehman's with vertical knife edges. Both are very stable. I need to adjust them once every few months. The knife edge supports are small Exacto knife blades set into the end of the stainless steel threaded boom rod with 'Marine Tex" epoxy. What no one ever tells you is that in order to balance the boom assembly you must attach the suspension point on the boom at the exact point where the whole thing is in balance when held vertically by its suspension wire. If the whole boom assembly rests in a horizontal position when you hold it like a vertical pendulum, then when you attach it to the frame, to act as a "garden gate", then it will be in perfect balance with respect to the knife edge trying to move up or down on it's support. My Lehman's are on Corian counter top material braced along the sides and near the main support with sections of aluminium sliding door track. When my first seismometer would not centre, I found that it was because the base flexed - that was when I added the aluminium stengtheners. I hope this helps, Martin _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Seismograph From: barry lotz gbl@....... Date: Tue, 06 Jul 1999 19:41:13 -0700 Marchal I have used 3/4" copper water pipe for the support frame.The joints are mitered and soldered. The geometry isn't to complicated. One triangle in the horizontal plane at the bottom(vertex at the hinge end) and one triangle from the top flexture and meeting the lower triangle at the boom free end , and one single vertical for the rear mast. I believe in triangles(not to much flexturing). Triangular shapes will result in mostly axial loads and are stiffer. I like the tension hinge arrangement shown on Sean Thomas's web site, though I have been successfully using knife edges with my seismometer for years. Just a little more input. Regards Barry Marchal van Lare wrote: > Hello Meredith, Angel and others, > > Thank you for your recommendations. > > Yes, I use the original Lehman knife edge design, since its > quite unstable, I am gonna try to use Angel's version. > > Tomorrow I will check a local machine tool store, to find out > if they have some surplus materials. > > I am thinking of a 20-30 cm wide frame, to get it as stable as > possible. > > I will let you know more tomorrow. > > Thank you for your help. > > Best regards, > > Marchal van Lare > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: eq alarm and map pages are up again From: The Lahrs JohnJan@........ Date: Tue, 06 Jul 1999 22:33:44 -0600 I figured out what I was doing wrong and got the earthquake map and alarm web page working again. Sorry for the recent problems! John http://geohazards.cr.usgs.gov/fingview/fingerview.html John C. Lahr POB 1529 Golden, CO 80402 (303) 215-9913 http://lahr.org/john-jan I am only one But still I am one. I cannot do everything and because I cannot do everything I will not refuse to do the something that I can do. Edward Everette Hale _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: sound picture? From: "Bonnie Schafer" bschafer@......... Date: Wed, 7 Jul 1999 05:52:05 -0700 Hi Ted, Thank you for writing. How woud I go about setting up this "mone"? Thanks Bonnie the crafty crafter _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Seismograph From: Marchal van Lare vanlare@.............. Date: Wed, 7 Jul 1999 10:49:24 -0400 Hi all, Here is my update on the progress on my Lehman: I've been able to get some surplus metal parts, and now I'm able to build a frame like Nick Caporossi's Lehman as you can see on www.webspan.net/~bbarns (thanks Bob). The dimensions will be about the same as in the Scientific American article. I think I will stick to the knife edge design, but I have a question about the knife edge, does it have to be sharp to function? (in other words, the sharper the better? ). What material can I use other than a curtain rod? Best regards, Marchal van Lare _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Seismograph From: S-T Morrissey sean@........... Date: Wed, 7 Jul 1999 13:34:25 -0500 (CDT) Marchal, 2 cents worth: I would strongly recommend that you avoid the knife edge concept for the boom pivot. The ground motions and/or the required stability for a useful long period require controlling the fixed end of the boom in the sub-micron range, which is significantly less than the roughness of the surfaces of the knife-edge idea. Seismometers have always used a flat flexure(s) or a taught wire for pivot points: nothing moves with respect to anything to make micro-positioning noise. For the boom, I would suggest aluminum channel material, like a U-shape 0.5" high by 0.75" wide (USA dimensions) with a wall thickness of at least 3/16". Aluminum stock is widely available at most hardware stores. Even handier would be threaded rod at least 1/2" inch diameter; you can find brass, aluminum, or stainless steel and matching nuts (at a Tru-Value store): common steel rod is magnetic and will not work. In fact, the only place for magnetic material in a seismometer is in the magnet itself. The large-diameter (I would use 1 1/2" material or larger) soldered copper tubing frame sounds like a good idea, although again I would prefer to use large aluminum channel or angle (2" x2" x 1/8" wall) that are bolted and epoxied at the joints. I would keep in mind that I want something sturdy enough to stand on without damage, as this would probably provide long term stability and support for a horizontal seismometer. The big LP seismometers use aluminum castings 0.5" and up in thickness, and triangular supports for the boom mast. Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: PSN - Questions (Again) From: "Rex Klopfenstein, Jr" rklopfen@......... Date: Thu, 08 Jul 1999 13:31:12 -0400 Sean Well I have got my two SG units running and they have recorded several quakes. I now have time to start building a version of your VBB. I have drawn up a version of your circuit which will have a period of 80 seconds (running) and 1 second (zeroing). I plan to use a 4PDT relay so that I can switch remotely. I also plan to put the 'zero motor' control and calibrate pulse trigger in a remote station along with the period select switch. I am currently in the process of wiring up the circuits and have come to a point where I will have to start cutting metal so that I can check out my VRDT (the easiest way I can figure out to make a test rig!). As soon as I get my boards wired, I will post the drawings. I do have several questions on your bridge amplifier/Demod circuit for the VBB. First, are you using the jumpers near the two 10mF elect and the 10K pot? Second, are you using the switch near the two 47mF; if so, what position? I do also have another question. What are the values of the elect capacitor (C11-C14) on the Seismic Amplifier circuit that you sent me? I can guess that these would about 25mF Tant? Thanks in advance -- Rex Klopfentein, Jr. rklopfen@......... http://www.wcnet.org/~rklopfen _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Additional Photos From: "Rex Klopfenstein, Jr." rklopfen@......... Date: Thu, 08 Jul 1999 21:38:39 -0400 I finally used up the film in my camera! I have added pictures of my 'seismic vault' and the damping calibration rig I built. -- Rex Klopfenstein, Jr. Bowling Green, OH rklopfen@......... www.wcnet.org/~rklopfen _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Additional Photos From: meredith lamb psnseismograph52@.......... Date: Thu, 08 Jul 1999 19:58:28 -0600 "Rex Klopfenstein, Jr." wrote: > I finally used up the film in my camera! I have added pictures of my > 'seismic vault' and the damping calibration rig I built. > Rex, Thanks for the additional views, its most interesting to see what others have done or are doing. Appreciate the large sized photos, its easier to pick up on more items. The mechanical quality of your instruments is impressive. I like the milled slots for adjustments you made. I see you left space in the vault for the STM-8 vertical. That will be of high interest to see photos on sometime. Thanks, Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: RE: Seismograph From: robert barns 75612.2635@.............. Date: Fri, 9 Jul 1999 11:32:28 -0400 Martin, I disagree with two points you made in your reply to Marchal. 1. I se= e no need to balance the boom around the wire attachment point. 2. I thin= k that using a knife edge for the boom pivot is asking for complications. = If the knife edge is longer than say 1/16", there will be uncertainty as to the location of the actual point of contact since this will vary as the boom is positioned up or down from where the knife edge is exactly parall= el with its contact surface. I think that using a ball end (say 1/8" dia.) = or a disk is easier. I have put a photo of my pivot which uses a disk (abou= t 1 1/2" in dia.) on my web site. www.webspan.net/~bbarns The disk simply rests on a flat brass bar. This makes it easy to positio= n the contact since it can be anywhere on the bar. Many hardware stores carry 1/2" dia. aluminum rod. I think that this i= s good for the boom. Bob Barns _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Seismograph From: meredith lamb psnseismograph52@.......... Date: Fri, 09 Jul 1999 11:13:59 -0600 robert barns wrote: > > I think that using a ball end (say 1/8" dia.) or > a disk is easier. I have put a photo of my pivot which uses a disk (about > 1 1/2" in dia.) on my web site. www.webspan.net/~bbarns > The disk simply rests on a flat brass bar. This makes it easy to position > the contact since it can be anywhere on the bar. > Many hardware stores carry 1/2" dia. aluminum rod. I think that this is > good for the boom. > Bob Barns > Bob, Went to your web site and saw the pivot. Your disk roughly resembles a glass cutter metal disk. I presume its like a washer put in a drill press collet with a bolt/nut attachment and filed down as it was spun? Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: STM-8 CONSTRUCTION From: S-T Morrissey sean@........... Date: Fri, 9 Jul 1999 12:51:49 -0500 (CDT) Jim, Regarding your questions of June 27: As I have often said before, I don't think that there is anything particularly special in the dimensional selections for the STM-9 vertical seis. I suppose I could say that my design is mostly intuitive, based on many years of experience. Essentially, I started out with a leaf-spring, added a mass and a boom to connect them, which required hinges for the boom and flexures for the spring, etc. And it works with a self noise level and stability much better than I anticipated. Regarding the square tubes that are part of the spring clamp: the idea is to apply a firm continuous termination of the stresses across the end of the spring, rather than just a few screws. I also thought it would avoid thermally sensitive micro-stresses that a row of screws would create. It seems to work. If I had a mill, I would consider milling an 0.018" slit lengthwise through the center of a 1/4 " brass bar for the ends of the leaf spring; the 0.010 slits at the ends for the flexures would have to be at a right angle to the slit for the spring. I attached the flexures to the brass bars by means of centered slits in the 3/16" bars for several reasons (compared to soldering them to the side of the bar): it is much stronger; it dosn't apply any torque to the bar; it is much more creep resistant, etc. The slits are easy to do with a 0.010" jewelers saw blade available at True-Value stores. I use a jig to get it centered and square. THe brass cuts like butter when making such a fine slit. When I solder in the bronze flexures, I am careful to apply the heat (from a small torch) only to the brass bar itself so as not to soften the temper of the flexures. If the flexure strips DO get heated, I restore the temper by immediately spraying them with water. I did some evaluation of the braided stainless fishing leader, but it presents problems in fastening it to the bars. Feeding it through a small hole in the bar and crimping a band (from the crimp part of a connector pin) on the ends seems to work. THen it is epoxied into the hole under tension to prevent micro-positioning noise. I did not use this flexure in a completed seis yet, so I don't know how it compares noise-wise to the flat strips. But I may have to use it to work up an alternative to the "Lehman" design that uses only taught wires for the boom suspension (using guitar strings.) Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: STM circuit questions From: S-T Morrissey sean@........... Date: Fri, 9 Jul 1999 13:57:43 -0500 (CDT) Rex, I assume that you realize that the SG design can be configured as a VBB system using its capacitive displacement detector, or by replacing the latter with a VRDT. For the STM-8, you might want to consider having the zero motor control switch be a 3PDT with the extra pole activating the relay to switch to the shorter period while zeroing. Regarding the demodulator schematic: some things are still left over from the tiltmeter application, but may be useful. Using numbers from your schematics: The jumper J1 at R23 and C12,13 is to provide about 10x gain for the AC bridge amplifier. I have found that this makes the sensitivity too high to work with for the VRDTs that I make. But there is an additional 10x gain in the DC displacement amplifier that could be omitted if the demodulator gain is already 10xed. But a VRDT with 2500 mv/micron is difficult to calibrate, even with a differential micrometer. On the other hand, if the VRDT gap (between the coils) is large (like 3-5mm) the added AC gain may be necessary to get a nominal output. Switch S3 and C16,17 are a low pass filter. I am using 0.47uf, as well as other values (as low as 0.001), to play with the loop response at high frequencies vs instabilities. Also, the VRDT calibration switch S1 and resistors R12,14, 1nd 15 are optional as far as the seis is concerned. The VBB seis is calibrated with DC current in the auxilliary calibration coil. The values of the resistors assume that the VRDT reactance change is 22 ohms / 10*microns, and are handy for evaluating amplifier gains, etc. The same can be said for the "zero-test" switch S2 and R16-18: it is very useful for evaluating the circuit performance, but not used in the normal operation of the seis. For this reason, these are mounted on the bridge amp board, rather than being on the control box panel. Regarding the seismic amplifier, the capacitors C11-14 are for power supply filtering, and can be any handy value; they are in pairs at opposite ends of the amp board. Also, the DC-blocking or 60/90 second high-pass capacitors C17-20 and C21-24 are to remove the amplifier DC offset from the telemetry VCO (voltage controlled oscillator) input to keep the FM carriers from wandering around (we had only 90hz of "guard band" between each channel). The 330uf capacitors are expensive, and they can be replaced with the jumpers at J1 and J2. Also, the gain switch(es) can be replaced with selected gain resistors to save money. An overall gain of 60db (x1000) (S5 + S9) is a handy value, although a max of 90db (x 32768) (S7 + S10) may be necessary for a small geophone. Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Farewell Party for Ted Blank & Family, Sunday July 11th From: Larry Cochrane cochrane@.............. Date: Fri, 09 Jul 1999 14:00:20 -0700 For the N.Cal. PSNers; Ted Blank and family will be moving away from the area soon. They are having a farewell party on Sunday. See below for more information. -Larry Cochrane Redwood City, PSN >From: gleisner@.......... >To: cochrane@.............. >Date: Fri, 9 Jul 1999 10:03:28 -0400 >Subject: Farewell Party for Ted Blank & Family, Sunday July 11th > > > >Larry, Thanks so much for sharing this with the seismology crowd ... > >We're leaving San Jose - We'd Like to Say Farewell to YOU!! >When: Sunday July 11th - open house starting at 2pm >Where: 954 Foxswallow Ct., San Jose >RSVP: Acceptances only - 408/323-8415 or 1152 (fax) >Mementos: We're making a family scrapbook so anything, ie pictures, you might > have to help us remember you and the good times in sunny California >appreciated > >Directions: 85 south, exit Almaden X'way. South on Almaden X'way about 4 >miles. >Turn left on Via Valente light (PW on left) - 2nd right onto Bret Harte. >After stop sign - 2nd left onto Shearwater - 2nd left onto Foxswallow, 1st house >on left. > >Our New Address: >238 Highland Street >Portsmouth, NH 03801 >603/433-9180 >603/433-9190 (Fax) > > >Regards, Tina Gleisner >Program Director, eCommerce Architecture & Project Management >gleisner@........... calendar indicates NY/CA >NY: 914.784.3256 (8.863); fax x6045 >CA: NY tieline rings in CA or 408.268.4925; fax 408.323.5512 > > > > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Farewell Party for Ted Blank & Family, Sunday July 11th From: Edward Cranswick cranswick@........ Date: Fri, 09 Jul 1999 15:39:06 -0600 Ted & Family- It has been a long trip so far for you all around the world -- Wappinger's Falls, Japan, Moscow (where you met Tanya, my ex-mother-in-law, before I did), San Jose -- and now Back East again. I am glad I had a chance to visit you at home in San Jose and do last year's AGU PSN presentation with you and Jan Froom and all the kids and the teachers. I am sorry to miss your goodbye party. I wish you well and look forward to records from the old stable craton in Maine. -Edward Larry Cochrane wrote: > For the N.Cal. PSNers; > > Ted Blank and family will be moving away from the area soon. They are > having a farewell party on Sunday. See below for more information. > > -Larry Cochrane > Redwood City, PSN > > > >From: gleisner@.......... > >To: cochrane@.............. > >Date: Fri, 9 Jul 1999 10:03:28 -0400 > >Subject: Farewell Party for Ted Blank & Family, Sunday July 11th > > > > > > > >Larry, Thanks so much for sharing this with the seismology crowd ... > > > >We're leaving San Jose - We'd Like to Say Farewell to YOU!! > >When: Sunday July 11th - open house starting at 2pm > >Where: 954 Foxswallow Ct., San Jose > >RSVP: Acceptances only - 408/323-8415 or 1152 (fax) > >Mementos: We're making a family scrapbook so anything, ie pictures, you > might > > have to help us remember you and the good times in sunny California > >appreciated > > > >Directions: 85 south, exit Almaden X'way. South on Almaden X'way about 4 > >miles. > >Turn left on Via Valente light (PW on left) - 2nd right onto Bret Harte. > >After stop sign - 2nd left onto Shearwater - 2nd left onto Foxswallow, 1st > house > >on left. > > > >Our New Address: > >238 Highland Street > >Portsmouth, NH 03801 > >603/433-9180 > >603/433-9190 (Fax) > > > > > >Regards, Tina Gleisner > >Program Director, eCommerce Architecture & Project Management > >gleisner@........... calendar indicates NY/CA > >NY: 914.784.3256 (8.863); fax x6045 > >CA: NY tieline rings in CA or 408.268.4925; fax 408.323.5512 > > > > > > > > > > _____________________________________________________________________ > > 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) Subject: North East USA? From: Nick & Sophie Caporossi nickcap@............. Date: Sat, 10 Jul 1999 17:37:56 -0400 To PSN group: The ldgo.columbia.edu at: >http://quake.wr.usgs.gov/cgi-bin/finger?quake@................. > had been listing quakes and other seismic activity on the East Coast of the USA. It had been covering an area from Maine to Virginia and parts of Ontario Canada. It is no longer doing so. Does any one know of another site that has the same information? On the subject of seismic activity, it would be informative if there was some discussion on what we are seeing when the sensor detects an event. Since I am novice in the field of seismology, I have a few of questions. 1: In some Earthquakes, why is it that the "P" and "S" waves do not arrive at the time where I would expect them to? 2: In some quakes, the Event starts with a large Spike and then gradually decreases. Why? 3: Why do some quakes gradually swell. They look like a rubber garden hose that is on the verge of blowing up. The 6.3 in the Solomon Islands on 7/9/99 made that kind of an unusual foot print. Nick _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: North East USA? From: Greg ghost@............. Date: Sat, 10 Jul 1999 22:33:53 -0700 Nick & Sophie Caporossi wrote: > > To PSN group: > The ldgo.columbia.edu at: > >http://quake.wr.usgs.gov/cgi-bin/finger?quake@................. The finger server is not responding directly. I thought it might have been a broken cgi script, but it wasn't. You're best bet is to write to root@................. or maybe administrator@................. or maybe postmaster. It might be under attack or taken down by accident. Finger servers provide a lot information for crackers (bad hackers) and sys admins take them down to limit that. > Canada. It is no longer doing so. Does any one know of another site that > has the same information? There might be a ftp server or mailing list with the exact same info. The sys admin (root) would know for sure. > 1: In some Earthquakes, why is it that the "P" and "S" waves do not arrive > at the time where I would expect them to? I'll skip that one for someone else to wrestle with. > 2: In some quakes, the Event starts with a large Spike and then gradually > decreases. Why? > > 3: Why do some quakes gradually swell. They look like a rubber garden hose > that is on the verge of blowing up. The 6.3 in the Solomon Islands on > 7/9/99 made that kind of an unusual foot print. I try to imagine the plates actual contact and movement. Is is hard rock snapping? Or maybe more like a landslide giving way. Good luck with that finger info, Greg _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Moderate Quake From: Wayne Abraham J73WA abrahamw@........ Date: Sun, 11 Jul 1999 08:43:51 -0400 A moderate earthquake was recorded and felt here on Dominica around 07:58 today. USGS does not have it listed. The badly clipped .bbl file has been added to Larry's archive. DM1, 2 and 3 files will be submitted later today. -- Wayne Abraham 1430 Rodney Street Portsmouth, Dominica abrahamw@........ http://www.freeyellow.com/members6/dominicapsn/ _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: North East USA? From: bc bruce@....... Date: Sun, 11 Jul 1999 09:32:39 -0400 I'm not sure if they publish current activity but you might check the Weston observatory at Boston College http://www.bc.edu/bc_org/avp/cas/wesobs/default.html Bruce At 05:37 PM 07/10/1999 -0400, you wrote: >To PSN group: > The ldgo.columbia.edu at: >>http://quake.wr.usgs.gov/cgi-bin/finger?quake@................. > had been >listing quakes and other seismic activity on the East Coast of the USA. It >had been covering an area from Maine to Virginia and parts of Ontario >Canada. It is no longer doing so. Does any one know of another site that >has the same information? > > On the subject of seismic activity, it would be informative if there was >some discussion on what we are seeing when the sensor detects an event. >Since I am novice in the field of seismology, I have a few of questions. > >1: In some Earthquakes, why is it that the "P" and "S" waves do not arrive >at the time where I would expect them to? > >2: In some quakes, the Event starts with a large Spike and then gradually >decreases. Why? > >3: Why do some quakes gradually swell. They look like a rubber garden hose >that is on the verge of blowing up. The 6.3 in the Solomon Islands on >7/9/99 made that kind of an unusual foot print. > >Nick > >_____________________________________________________________________ > >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) Subject: Quake peaking monitor now From: meredith lamb psnseismograph52@.......... Date: Sun, 11 Jul 1999 08:32:47 -0600 Quake coming in starting about 14:21 utc....fairly strong with monitor overscales. Still fairly strong at 14:33. Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: BIG QUAKE ON AIR NOW From: "Giovanni Rotta" rottag@.......... Date: Sun, 11 Jul 1999 16:43:33 +0200 Italian stations are recording a large quake (M. 6.1) 16:26 UTC Giovanni Rotta Via F. Pizzigoni, 10 33010 Resia (Udine) I Lat. 46.373 N Long. 13.305 E rottag@..........
Italian stations are recording a large quake (M. = 6.1)=20 16:26 UTC
 
Giovanni Rotta
Via F. Pizzigoni, 10
33010 = Resia=20 (Udine) I
Lat. 46.373 N  Long. 13.305 E
rottag@..........
Subject: Sesmicity Viewer and audio Earthquake Alarm From: meredith lamb psnseismograph52@.......... Date: Sun, 11 Jul 1999 09:16:47 -0600 Tried John Lahr's USGS web site: http://geohazards.cr.usgs.gov/fingview/fingerview.html for this central america quake. The Seismicity Viewer is still slow loading (probably because of this quake computer overload). The Earthquake Alarm shows "Not Found", but, the audio signal came through regardless about 15:01 utc. It sounds like a finch here. Meredith Lamb -- Main Web site: http://www.users.uswest.net/~psnseismograph52/Index.html and.... http://members.xoom.com/seismogram/Index.html a mirror site. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Quake peaking monitor now From: barry lotz gbl@....... Date: Sun, 11 Jul 1999 08:39:26 -0700 Meredith I was awaken by SDR singing. I realized that only the Lehman was acting up. After exorcizing a small spider I went back to bed. About 1 minute later it began again. What's with this spider? Opps, all the sensors were active now. This wasn't a false alarm. Barry meredith lamb wrote: > Quake coming in starting about 14:21 utc....fairly strong with > monitor overscales. Still fairly strong at 14:33. > > Meredith Lamb > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Quake peaking monitor now From: meredith lamb psnseismograph52@.......... Date: Sun, 11 Jul 1999 09:50:11 -0600 barry lotz wrote: > Meredith > I was awaken by SDR singing. I realized that only the Lehman was acting > up. After exorcizing a small spider I went back to bed. About 1 minute > later it began again. What's with this spider? Opps, all the sensors were > active now. This wasn't a false alarm. > Barry > > meredith lamb wrote: > > > Quake coming in starting about 14:21 utc....fairly strong with > > monitor overscales. Still fairly strong at 14:33. > > > > Meredith Lamb > > SPIDERS AND FINCH BIRD SIGNALS.....HA. Hi Barry, This seems like a weekend deal anymore....a quake to wake up the morning oversleepers. Am monitoring the earthquake alarm site, for the finch bird "alarm". When I first tried it, the sound kind of startled me, till I realized that was the signal.... I like it....ha. Still getting low level long period stuff....maybe 9 seconds from the quake, and, still recording. Note alot of stations around the world clipped. Red Puma max mag shows a preliminary of around 6.1, but, I have a feeling it may eventually be assigned a larger magnitude. The Vancouver area quakes weren't near as large if I remember vaguely right. Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Quake peaking monitor now From: DGentry509@....... Date: Sun, 11 Jul 1999 12:23:21 EDT Hondurus 1414:15 15.70N 88.26W 10.0 6.6Ms A finger 2 quake via matt drudge home page _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Quake peaking monitor now From: barry lotz gbl@....... Date: Sun, 11 Jul 1999 09:30:23 -0700 Meredith I agree, I see the new event in the higher 6's. I saved some data from Brazil BDFB station via autodrum. It's great to get data from elsewhere in the world (in near real time) and be able to incorporate it with ones station in Winquake with the location map. Barry _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Fwd: Quake Shakes Guatemala, Honduras From: Seisguy@....... Date: Sun, 11 Jul 1999 12:26:38 EDT Quake Shakes Guatemala, Honduras ..c The Associated Press GUATEMALA CITY (AP) - A strong earthquake shook the Caribbean coast of Guatemala and Honduras on Sunday, damaging some buildings. There were no immediate reports of injuries. The U.S. Geological Survey in Golden, Colo., reported the quake's magnitude at 6.6 while Guatemala's Seismological Station estimated the force at 5.9. The preliminary center point was located about 20 miles east of the Guatemalan coastal city of Puerto Barrios, according to Jim Taggart, a geophysicist with the survey's National Earthquake Information Center. The quake occurred at 8:14 a.m. local time (10:14 a.m. EDT), provoking alarm among people across Guatemala. It damaged buildings in eastern Guatemala, including the Our Lady of the Trinity church in Chiquimula, 90 miles southwest of Puerto Barrios. Guatemala's disaster-relief agency CONRED was surveying the rest of the nation for reports of damage or injuries. The quake was felt in the Honduran capital of Tegucigalpa, 150 miles southeast of Puerto Barrios, and in the Mexican city of Villahermosa, 330 miles to the northwest. It also was felt in El Salvador and Belize. AP-NY-07-11-99 1225EDT Copyright 1999 The Associated Press. The information contained in the AP news report may not be published, broadcast, rewritten or otherwise distributed without prior written authority of The Associated Press. To edit your profile, go to keyword NewsProfiles . For all of today's news, go to keyword News. Subject: Fwd: Quake Shakes Guatemala, Honduras From: Seisguy@....... Date: Sun, 11 Jul 1999 12:27:56 EDT Quake Shakes Guatemala, Honduras ..c The Associated Press GUATEMALA CITY (AP) - A strong earthquake shook the Caribbean coast of Guatemala and Honduras on Sunday, damaging some buildings. There were no immediate reports of injuries. The U.S. Geological Survey in Golden, Colo., reported the quake's magnitude at 6.6 while Guatemala's Seismological Station estimated the force at 5.9. The preliminary center point was located about 20 miles east of the Guatemalan coastal city of Puerto Barrios, according to Jim Taggart, a geophysicist with the survey's National Earthquake Information Center. The quake occurred at 8:14 a.m. local time (10:14 a.m. EDT), provoking alarm among people across Guatemala. It damaged buildings in eastern Guatemala, including the Our Lady of the Trinity church in Chiquimula, 90 miles southwest of Puerto Barrios. Guatemala's disaster-relief agency CONRED was surveying the rest of the nation for reports of damage or injuries. The quake was felt in the Honduran capital of Tegucigalpa, 150 miles southeast of Puerto Barrios, and in the Mexican city of Villahermosa, 330 miles to the northwest. It also was felt in El Salvador and Belize. AP-NY-07-11-99 1225EDT Copyright 1999 The Associated Press. The information contained in the AP news report may not be published, broadcast, rewritten or otherwise distributed without prior written authority of The Associated Press. To edit your profile, go to keyword NewsProfiles . For all of today's news, go to keyword News. Subject: Re: Seismograph From: robert barns 75612.2635@.............. Date: Sun, 11 Jul 1999 13:56:26 -0400 Meredith, Good deduction! The disk was a washer I found in my junk box. Bob Barns _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: North East USA? From: John Hernlund hernlund@....... Date: Sun, 11 Jul 1999 12:21:21 -0700 (MST) On Sat, 10 Jul 1999, Nick & Sophie Caporossi wrote: > listing quakes and other seismic activity on the East Coast of the USA. It > had been covering an area from Maine to Virginia and parts of Ontario > Canada. It is no longer doing so. Does any one know of another site that > has the same information? There is a good global catalog hosted by Berkeley's seismo lab web site. All you do is input the min/max latitude and longitude and the beginning and end time and a few other parameters and the computer will build a list of all quakes in that area. I am not sure how often it is updated, but it seems fairly thorough. I don't remember the address, but you can find it by clicking through www.berkeley.edu to their site. > On the subject of seismic activity, it would be informative if there was > some discussion on what we are seeing when the sensor detects an event. > Since I am novice in the field of seismology, I have a few of questions. > > 1: In some Earthquakes, why is it that the "P" and "S" waves do not arrive > at the time where I would expect them to? The way that "expected" travel times are found is only by reference to a large compilation of seismograms for various epicentral distances. The arrivals are averaged and formed into one of the standard earth models (like IASPEI, PREM, J-B, etc.). However, since this averaging is done over the whole globe regardless of location, the result is that differences in velocity caused by anomalies in various locations are not resolved. When the ray path for the waves between a quake and source encounter one of these so-called "lateral heterogeneities" the expected travel time differs from the real travel time. Newer techniques have been used for quite some time now that use knowledge of the wave ray path and the difference in real travel time and expected travel time from a model to make a map of these irregularities based on changes in their seismic velocities. This is usually called "tomography," a word which is borrowed from medical techniques that use X-rays and other sources. Tomography is a fairly simple technique that uses a matrix inversion to solve for the velocity map of the medium, but it produces pretty pictures of the interior that everyone loves to look at and attempt an interpretation. Lateral heterogeneities are probably always caused by changes in chemistry or temperature in the Earth's interior that are in turn caused by large scale churning in the mantle. The reason this churning or convection occurs is because the core releases heat into the mantle, which is a relatively poor conductor of heat. Hence heat pools up in spots, making the mantle material expand and become more buoyant. This causes the mantle to deform and move to accomodate the transfer of heat. Another important lateral heterogeneity occurs because some portions of the Earth's crust are much thicker than others. For instance, the ocean crust is usually half as thick as continental crust... > 2: In some quakes, the Event starts with a large Spike and then gradually > decreases. Why? > 3: Why do some quakes gradually swell. They look like a rubber garden hose > that is on the verge of blowing up. The 6.3 in the Solomon Islands on > 7/9/99 made that kind of an unusual foot print. Both these questions are related. There are many possibilities: 1) Source: The simplest answer to your question is that faults move at different rates and usually in a very jumpy manner. The first P-arrival is usually very good to use to identify the behavior of the fault motion that created the quake. Also, faults are not point sources, but lie along a plane. Deep earthquakes will also look different. Also, depending on how your station is oriented with respect to the fault plane will change the manner of waves coming toward you. 2) Medium: The second way the shape of the first arrival can be changed is by the material the waves pass through. Small differences can be smoothed out in the Earth when the waves pass through regions with variations in seismic velocities. Imagine a bunch of pin balls being dropped into a large pin ball machine with many bumpers and obstacles. No matter how you arrange their pattern when starting the drop, they will bounce around and come out more randomly at the bottom than at the top. This randomness is a smoothed version of the original pattern. 3) Instrument: Your recording instrument will also impose a change in shape of the wave arrivals because of its characteristics as a pendulum. The seismogram is the "convolution" of the real wave form and your instrument's "impulse response function." The impulse response is the way your seismometer responds to a sharp input spike. A convolution can be found analytically by taking the product of the LaPlace or Fourier Transforms for each function and then inverting back to the time domain. It can also be found numerically (in the case of digital data) by summing the two records a(i) and b(j) as SUM[a(i)*b(i-j)]. If a(i) is the real wave form and b(j) is the impulse response you can see that a response of b(j) = 1,0,0,0,0,0,... is that of a seismometer that imposes no change in the wave form and most accurately represents the ground motion. The above sum returns the exact copy of a(i). However such an impulse response is not physically possible for any real seismometer. Because of this fact, the seismogram will always be more broadened than the real wave form. The amount of broadening depends on your specific instrument. A broadband instrument will partially correct for this effect for some frequency range by using feedback electronics. John Hernlund E-mail: hernlund@....... WWW: http://www.public.asu.edu/~hernlund/ ****************************************************************************** _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Fwd: 37 Hurt in Central American Quake From: Seisguy@....... Date: Sun, 11 Jul 1999 19:05:54 EDT 37 Hurt in Central American Quake ..c The Associated Press By ALFONSO ANZUETO GUATEMALA CITY (AP) - A strong earthquake shook the Caribbean coast of Guatemala and Honduras on Sunday, injuring dozens of people and damaging a U.S. military base as windows shattered and walls cracked across the region. At least 37 people were reported injured, many with broken bones, in the eastern Guatemalan province of Izabal, Vice Gov. Adolfo Hernandez said. The U.S. Geological Survey in Golden, Colo., reported the quake's magnitude at 6.6, while Guatemala's Seismological Station estimated the magnitude at 6.1, up from an initial report of 5.9. The quake, which occurred at 8:14 a.m. local time (10:14 a.m. EDT), provoked alarm among people across Guatemala, Belize, Honduras and El Salvador. The preliminary center point was located about 20 miles east of the Guatemalan coast city of Puerto Barrios, according to Jim Taggart, a geophysicist with the survey's National Earthquake Information Center. Roads buckled and buildings cracked at a temporary U.S. military base in Puerto Barrios, said Lt. Col. Jeff Keane, a U.S. Army reservist who was across the border in Honduras at the Soto Cano Air Base, where he is based, when the quake struck. ``We were in a building. The building started shaking and telephone poles began tilting as the ground trembled. It lasted over a minute,'' Keane told The Associated Press by telephone from Honduras. About 200 U.S. Army reservists from Massachusetts and Connecticut are stationed in Puerto Barrios to help build schools and repair infrastructure damaged last year in Hurricane Mitch, Keane said. But the schools they are building appeared not to be damaged, he said. There were no reports of injuries at either base in Guatemala or Honduras. But aftershocks continued Sunday in Puerto Barrios. The earthquake damaged buildings in eastern Guatemala, including the Our Lady of the Trinity church in Chiquimula, 90 miles southwest of Puerto Barrios. Windows shattered at the international airport at Santa Elena and the Guatemalan Air Force base, both in the northern province of Peten. The quake also cut power to towns in Guatemala's northern and eastern regions. Guatemala's disaster-relief agency, CONRED, was surveying the rest of the nation for any further damage or injuries. In Honduras, the quake caused minor damage, such as cracked walls at a hospital in the northern city of El Progresso and fallen electrical poles along the north coast. ``The quake alarmed Hondurans but did not cause deaths or injuries ... only fear,'' said Jose Zelaya, a Red Cross spokesman in Tegucigalpa, the Honduran capital. Seismologists in El Salvador said the quake lasted one minute 10 seconds and was felt across their country. The Red Cross in El Salvador told local radio there were no reports of damage or injuries. The quake was felt as far away as the Mexican city of Villahermosa, 330 miles northwest of Puerto Barrios. AP-NY-07-11-99 1842EDT Copyright 1999 The Associated Press. The information contained in the AP news report may not be published, broadcast, rewritten or otherwise distributed without prior written authority of The Associated Press. To edit your profile, go to keyword NewsProfiles . For all of today's news, go to keyword News. Subject: SEISMO VIEWER From: "Francesco" franuc@...... Date: Mon, 12 Jul 1999 12:00:39 +0200 Hi all. It's on line the Northern Italy seismic sequence with Seismogram Viewer java-program at the usual web address http://space.tin.it/scienza/frnucer/sve.html (available from our home-page also). You should be able to run the Seismogram Viewer on any type of computer with internet access and a recent web browser that supports Java 1.0 or higher (i.e. Netscape 3 or higher, Internet Explorer 4 or higher). I.E.S.N. Francesco _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Computer card From: Arie Verveer ajbv@............ Date: Mon, 12 Jul 1999 20:20:01 +0800 Hi, The Y2K board woks fine. A recommendation; though as Larry stated the price is a little high. $60.0 (US), $129 (Australian). I just gave "SDR" a birthday, Y2K board, 1 gig hard disk and a network card. Arie Larry Cochrane wrote: > > > I bought a Y2K board a while back. I finally had some time to play around > with it the other day. It seems to work fine. I tried it on a non Y2K > complaint motherboard running SDR. After plug it in it fixed the date > problem without interfering with SDR. The board I bought is made by > American Megatrends Inc. It cost almost $60.00 USD, a little high for a > very small board that only has 3 ICs on it. The board also has a set of > jumpers to select the BIOS address. I just used the default setting of C800. > > -Larry Cochrane > Redwood City, PSN > > At 08:33 PM 7/4/99 +0800, you wrote: > >Hi, I thinking of buying a Y2K card that fits in the ISA slot of my old > >486 computer. It sounds quick and easy fix. Has anyone had any > >experience with this type of card. All the computer runs is Win95 > >(networked) and Larry's program SDR. > > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: More on Quakes From: Nick & Sophie Caporossi nickcap@............. Date: Mon, 12 Jul 1999 14:15:09 -0400 Hi: Thanks to all that responded to my questions on earthquakes. The suggested sites for listing of small and large motions of events in the North East of USA were a help. The responses that I received were quite informative. A special thanks to John Hernlund and Greg (don't know your last name). The recent Quake in Honduras was a classic. The "P" an "S" waves were right to the second. The "lq" wave fell right on the largest spike. It wiggled the basement floor for over an hour. Does that mean that the entire earth was moving for an hour? Again thanks Nick _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: More on Quakes From: John Hernlund hernlund@....... Date: Mon, 12 Jul 1999 11:57:26 -0700 (MST) On Mon, 12 Jul 1999, Nick & Sophie Caporossi wrote: > The recent Quake in Honduras was a classic. The "P" an "S" waves were right > to the second. The "lq" wave fell right on the largest spike. It wiggled > the basement floor for over an hour. Does that mean that the entire earth > was moving for an hour? The Earth was dancing a jig for quite a wihle I imagine. One thing to note about surface waves (lq, lr) is that they have a stronger variation in velocity than body waves (p, s, etc). This is because their velocity depends on the material in the uppermost reaches of the earth which is a lot more heterogeneous that the material in the lower mantle. Also, surface waves separate out into a continuous wave train because their velocities depend on their frequency (or period). This is because longer period waves oscillate deeper in the earth than shorter period surface waves, and this causes their velocities to depend on different materials. So if you get an original surface disturbance in the frequency range from 1-40 seconds then these waves will fan out from the source at different rates (called a group velocity). A standard reference period for surface waves is usually around 15 seconds because many seismometers respond well in this band. So I guess the lesson here is not to rely too much on the lq or lr arrivals being just right, because they probably will be off. An interesting thing to try is to take a good record with surface waves in it and do small, sharp (many poles) band pass filters for various periods from 10 to 40 seconds (0.1 to 0.025 Hz) and see how they appear different. Keep in mind that your instrument will also influence the results... John Hernlund E-mail: hernlund@....... WWW: http://www.public.asu.edu/~hernlund/ ****************************************************************************** _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Mammoth Lakes 3.8 From: Edward Cranswick cranswick@........ Date: Mon, 12 Jul 1999 22:34:10 -0600 Barry- I belatedly want to thank you for sending me these. I finally looked at them and was impressed from the spectra by what a truly low-frequency response they have. Again, teleseismology is not my forte' but it really looks like you guys are really getting down there! -Edward barry lotz wrote: > Hi Ed > They're small files (I try to save only 2X max FFT freq component). Please > understand, the sensors are an ever evolving process :) "AZ" are the ~20" sensor, and > "BZ" are the 12" sensor. In the 12" sensor I use a portion of a 16' measuring tape > return spring instead of the taping blade. > > Barry > > Edward Cranswick wrote: > > > Barry- > > Thank you. I look forward to seeing your records. > > -Edward > > > > ------------------------------------------------------------------------ > Name: 980816bz.bl > 980816bz.bl Type: unspecified type (application/octet-stream) > Encoding: base64 > > Name: 980823az.bl > 980823az.bl Type: unspecified type (application/octet-stream) > Encoding: base64 > > Name: 980830az.bl > 980830az.bl Type: unspecified type (application/octet-stream) > Encoding: base64 > > Name: 980903az.bl > 980903az.bl Type: unspecified type (application/octet-stream) > Encoding: base64 > > Name: 980914az.bl > 980914az.bl Type: unspecified type (application/octet-stream) > Encoding: base64 > > Name: 981109az.bl > 981109az.bl Type: unspecified type (application/octet-stream) > Encoding: base64 > > Name: 981207bz.bl > 981207bz.bl Type: unspecified type (application/octet-stream) > Encoding: base64 > > Name: 990128az.bl > 990128az.bl 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". _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: ted blank i need ur postal address From: "dave nelson" davenelson39@........... Date: Tue, 13 Jul 1999 01:40:34 PDT Ted, please e-mail me ur postal addy. that book u loaned me is in LA ready to be posted back to u by UPS. Im now back in new zealand cheers Dave Nelson _______________________________________________________________ Get Free Email and Do More On The Web. Visit http://www.msn.com _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Commercial Data Acquisition System From: John Lahr lahr@................... Date: Tue, 13 Jul 1999 09:15:20 -0600 (MDT) Here's a description of a fancy PC seismic data acquisition system, if you want to record many channels of data or a small network: JCLahr ********************** Dear Seismologist: In July, 1999 PC Systems is releasing ViSeis V2.45 the leading economical= =20 solution for small and medium-size seismic networks: a.. Lowest cost. A turnkey ViSeis system (P2-350 PC, GPS, 24-bit A-D,= =20 software loaded) $3250. OEM is $1450 (you supply the PC and timing).=20 b.. GPS support. GPS is transparently integrated into the system provid= ing=20 time stamped data.=20 c.. Multitasking. ViSeis tasks operate under Win98/95 allowing networki= ng,=20 FTP or remote control without interrupting the data acquisition.=20 d.. User interface. ViSeis is controlled via an intuitive graphical use= r=20 interface (see above).=20 e.. Flexibility. Up to 22-bits of dynamic range and 64 channels.=20 f.. Real technical support. ViSeis is supported by an experienced team = of=20 software and hardware engineers=20 g.. Standards. ViSeis it built using Labview, the world=92s most popula= r data=20 acquisition language.=20 h.. Extensibility ViSeis is modular allowing addition of new functional= ity=20 and hardware. For more information please contact: PC Systems Design Palo Alto, CA | Bozeman, MT www.pcsys-design.com info@................ _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: EqIP Interim Meeting From: John Lahr lahr@................... Date: Tue, 13 Jul 1999 09:23:58 -0600 (MDT) Earthquake Information Providers (EqIP) Dear EqIP members, I enjoyed the EqIP Interim Meeting today in Boulder. It was quite interesting learning what everyone is up to, and I'm glad that there is so much interest in K-12 education issues among many of the participants. The Open-File educational reports that I mentioned are: TABLE-TOP EARTHQUAKES A Demonstration of Seismology for Teachers and Students Open-File Report 98-767 http://lahr.org/john-jan/tabletop/ How to Build a Model Illustrating Sea-Floor Spreading and Subduction Open-File Report 99-132 http://lahr.org/john-jan/platemod/platemod.html (These reports are also on the USGS web site, http://greenwood.cr.usgs.gov but the versions on lahr.org will receive more frequent minor updates.) I consider these two reports "first drafts" and hope that, based on honest feedback from teachers, educators, and other scientists, I will have a sound basis for improving them. I also mentioned the Public Seismic Network. This is an informal group of mostly non-seismologists interested in seismology to the extent that many run their own seismic stations. Some run totally home-built seismometers and others have obtained either new equipment or obsolete equipment from seismic observatories. There are a number of web sites devoted to the PSN, but the most central is the site run by Larry Cochrane. At Larry's site one can sign up for the PSN mailing list, which currently reaches 282 people from around the world. This group is very helpful to anyone starting out in seismology and can provide a lot of pointers on setting up a seismograph station. I'm certain they would welcome questions from K-12 students and teachers as well. Cheers, John ################################## 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) Subject: Manual of Seismological Observatory Practice From: John Lahr lahr@................... Date: Tue, 13 Jul 1999 10:40:29 -0600 (MDT) The "Manual of Seismological Observatory Practice" is available in PDF format at this location: http://caldera.wr.usgs.gov/msop/index.html The Manual of Seismological Observatory Practice arose from a resolution of the United Nations Economic and Social Council, which was laid before the Committee for Standardisation of Seismographs and Seismograms of the International Association of Seismology and Physics of the Earth's Interior. This Committee met at Unesco House in Paris from March 12 to 15, 1963, and specified the general requirements of the Manual as follows: i. It would act as a guide for governments in setting up or running seismological networks. It would therefore include a selection of designs for recording stations, and suggestions for staffing and organisations both at the recording points and at a central office ii. It would contain all necessary information on instrumentation and procedure, to enable the station to fulfil normal international and local functions. iii. It would not contain any extensive account of the aims or methods of utilising the seismic data, as these were in the province of existing textbooks. Introduction The Manual of Seismological Observatory Practice was published in September, 1979 by World Data Center A for Solid Earth Geophysics as Report SE-20. The Manual's editor was P.L. Willmore of the Institute of Geological Sciences, Edinburgh, Scotland. The World Data Center A for Solid Earth Geophysics was a unit of the U.S. Department of Commerce, National Oceanic and Atmospheric Administration, Environmental Data and Information Service in Boulder, Colorado. The Manual has been out of print for many years and is still a standard reference work for seismologists. To make the Manual available again, we have provided this online version. The 159 pages of the manual were scanned by Mrs. Willie Lee, the resulting 159 TIF files were placed in ten Microsoft Word files by Dr. Willie Lee to provide continuity of page numbers. The Word files were converted to Adobe Acrobat Portable Document Format (PDF) files, hyperlinks were added, and this html front-end was created by Michael Diggles. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: EqIP Interim Meeting From: Edward Cranswick cranswick@........ Date: Tue, 13 Jul 1999 13:40:45 -0600 John- > I also mentioned the Public Seismic Network. This is an informal > group of mostly non-seismologists interested in seismology to > the extent that many run their own seismic stations. I would label members of the Public Seismic Network as "amateur seismologists". I think it is difficult to be as involved in seismology to the extent of operating ones own seismic station and be a "non-seismologist". -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) Subject: Re: EqIP Interim Meeting From: John Lahr lahr@................... Date: Tue, 13 Jul 1999 14:09:26 -0600 (MDT) Good point Ed! The Email to the EqIP group did not go out yet, so I'll make that change now. JCLahr > > John- > > > I also mentioned the Public Seismic Network. This is an informal > > group of mostly non-seismologists interested in seismology to > > the extent that many run their own seismic stations. > > I would label members of the Public Seismic Network as "amateur seismologists". I > think it is difficult to be as involved in seismology to the extent of operating > ones own seismic station and be a "non-seismologist". > -Edward _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: RE: equip Interim Meeting From: Victor.Taylor@......... Date: Tue, 13 Jul 1999 16:39:36 -0400 What ever! Along with the layman physicists, the layman geological seismologists, and don't forget the prospector, as well others in the commercial trade, and the technicians and engineers who design and build these apparatus. Who needs labels, when we have bread boards and testing and engineering and measuring, and our neat inter net seismic watch. what ever that is. Later, > -----Original Message----- > From: cranswick@........ [SMTP:cranswick@......... > Sent: Tuesday, July 13, 1999 3:41 PM > To: psn-l@.............. > Cc: eqip-l@....... > Subject: Re: EqIP Interim Meeting > > John- > > > I also mentioned the Public Seismic Network. This is an informal > > group of mostly non-seismologists interested in seismology to > > the extent that many run their own seismic stations. > > I would label members of the Public Seismic Network as "amateur > seismologists". I > think it is difficult to be as involved in seismology to the extent of > operating > ones own seismic station and be a "non-seismologist". > -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) > > To leave this list email listserver@.............. with the body of the > message: leave PSN-L _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Manual of Seismological Observatory Practice From: Raul Alvarez ralvarez@........ Date: Tue, 13 Jul 1999 18:43:04 -0600 Hello John, Has anyone had trouble downloading the files via FTP? Netscape cannot seem to find them. Raul John Lahr wrote: > The "Manual of Seismological Observatory Practice" is available > in PDF format at this location: > > http://caldera.wr.usgs.gov/msop/index.html > > The Manual of Seismological Observatory Practice arose from a resolution of the > United Nations Economic and Social > Council, which was laid before the Committee for Standardisation of Seismographs > and Seismograms of the International > Association of Seismology and Physics of the Earth's Interior. This Committee > met at Unesco House in Paris from March 12 > to 15, 1963, and specified the general requirements of the Manual as follows: > i. It would act as a guide for governments in setting up or running > seismological networks. It would therefore include a > selection of designs for recording stations, and suggestions for staffing and > organisations both at the recording points and at > a central office > ii. It would contain all necessary information on instrumentation and > procedure, to enable the station to fulfil normal > international and local functions. > iii. It would not contain any extensive account of the aims or methods of > utilising the seismic data, as these were in the > province of existing textbooks. > > Introduction > > The Manual of Seismological Observatory Practice was published in September, > 1979 by World Data Center A for Solid > Earth Geophysics as Report SE-20. The Manual's editor was P.L. Willmore of the > Institute of Geological Sciences, > Edinburgh, Scotland. The World Data Center A for Solid Earth Geophysics was a > unit of the U.S. Department of Commerce, > National Oceanic and Atmospheric Administration, Environmental Data and > Information Service in Boulder, Colorado. The > Manual has been out of print for many years and is still a standard reference > work for seismologists. To make the Manual > available again, we have provided this online version. The 159 pages of the > manual were scanned by Mrs. Willie Lee, the > resulting 159 TIF files were placed in ten Microsoft Word files by Dr. Willie > Lee to provide continuity of page numbers. The > Word files were converted to Adobe Acrobat Portable Document Format (PDF) files, > hyperlinks were added, and this html > front-end was created by Michael Diggles. > > _____________________________________________________________________ > > 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) Subject: Re: Manual of Seismological Observatory Practice From: Wayne Abraham J73WA abrahamw@........ Date: Tue, 13 Jul 1999 20:56:34 -0400 Raul I have the latest version of Netscape and downloaded the file effortlessly. Wayne Raul Alvarez wrote: > Hello John, > Has anyone had trouble downloading the files via FTP? > Netscape cannot seem to find them. > > Raul > > John Lahr wrote: > > > The "Manual of Seismological Observatory Practice" is available > > in PDF format at this location: > > > > http://caldera.wr.usgs.gov/msop/index.html > > > > The Manual of Seismological Observatory Practice arose from a resolution of the > > United Nations Economic and Social > > Council, which was laid before the Committee for Standardisation of Seismographs > > and Seismograms of the International > > Association of Seismology and Physics of the Earth's Interior. This Committee > > met at Unesco House in Paris from March 12 > > to 15, 1963, and specified the general requirements of the Manual as follows: > > i. It would act as a guide for governments in setting up or running > > seismological networks. It would therefore include a > > selection of designs for recording stations, and suggestions for staffing and > > organisations both at the recording points and at > > a central office > > ii. It would contain all necessary information on instrumentation and > > procedure, to enable the station to fulfil normal > > international and local functions. > > iii. It would not contain any extensive account of the aims or methods of > > utilising the seismic data, as these were in the > > province of existing textbooks. > > > > Introduction > > > > The Manual of Seismological Observatory Practice was published in September, > > 1979 by World Data Center A for Solid > > Earth Geophysics as Report SE-20. The Manual's editor was P.L. Willmore of the > > Institute of Geological Sciences, > > Edinburgh, Scotland. The World Data Center A for Solid Earth Geophysics was a > > unit of the U.S. Department of Commerce, > > National Oceanic and Atmospheric Administration, Environmental Data and > > Information Service in Boulder, Colorado. The > > Manual has been out of print for many years and is still a standard reference > > work for seismologists. To make the Manual > > available again, we have provided this online version. The 159 pages of the > > manual were scanned by Mrs. Willie Lee, the > > resulting 159 TIF files were placed in ten Microsoft Word files by Dr. Willie > > Lee to provide continuity of page numbers. The > > Word files were converted to Adobe Acrobat Portable Document Format (PDF) files, > > hyperlinks were added, and this html > > front-end was created by Michael Diggles. > > > > _____________________________________________________________________ > > > > 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 -- Wayne Abraham 1430 Rodney Street Portsmouth, Dominica abrahamw@........ http://www.freeyellow.com/members6/dominicapsn/ _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Manual of Seismological Observatory Practice From: The Lahrs JohnJan@........ Date: Tue, 13 Jul 1999 19:00:28 -0600 Raul and others, The link seems to be messed up. I did get the files from this URL: ftp://caldera.wr.usgs.gov/pub2/msop/ John **** Hello John, Has anyone had trouble downloading the files via FTP? Netscape cannot seem to find them. Raul John Lahr wrote: > The "Manual of Seismological Observatory Practice" is available > in PDF format at this location: > > http://caldera.wr.usgs.gov/msop/index.html > * John C. and Jan H. Lahr * * JohnJan@........ * * 1925 Foothills Road * * Golden, Colorado 80401-1718 * * (303) 215-9913 * * http://lahr.org/john-jan * * http://giseis.alaska.edu/lahr * _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Manual of Seismological Observatory Practice From: Raul Alvarez ralvarez@........ Date: Tue, 13 Jul 1999 19:03:54 -0600 Hi Wayne, thanks for the info. I was able to load the 290k file (the first 6 pages) but then tried to load the rest via FTP and was not able to. Then I tried to load from the sidebar of the first pages and netscape crashes each time. Oh well, will keep trying. Thanks again, Raul _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Manual of Seismological Observatory Practice From: Greg ghost@............. Date: Tue, 13 Jul 1999 18:07:31 -0700 Wayne Abraham J73WA wrote: Date: Tue, 13 Jul 1999 20:56:34 -0400 From: Wayne Abraham J73WA Organization: Golden Image X-Mailer: Mozilla 4.6 [en] (Win98; I) > I have the latest version of Netscape and downloaded the file effortlessly. There's a newer version out. :) 4.61 came out not too long after 4.6. There's almost no difference though. A couple of security and bug fixes. Isn't it fun? Download 18 MB and it's out of date 3 days later. 4.61 would probably make very little difference, I just thought it was kinda funny. ,Greg _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Suggestions anyone? From: Raul Alvarez ralvarez@........ Date: Tue, 13 Jul 1999 19:12:07 -0600 Hi All, Started working on a seismo vault here. Plans are to use an old, but still water tight, cistern that was on the property when we purchased it some five years ago. The cistern is 4 feet wide, 8 feet long and 5 feet high. The top is about 2 feet below grade. Seems like it would make a great seismo vault. My guess about it still being water tight is that it was mostly full of water but the outside ground is very dry. Since I pumped it out, water has not re-accumulated. My questions are: I want to be sure it will stay dry. What, if any, paint could be used to seal it from the inside? Also, after being in it a while, getting the last of the water and silt out, I got to thinking about the effects of the echoes created in such a box, and how they may affect a seismo. Any suggestions, comments ??? Raul _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: equip Interim Meeting From: twleiper@........ Date: Tue, 13 Jul 1999 22:49:25 -0400 What ever (squared) ! What we really need are some seischiatrists! On Tue, 13 Jul 1999 16:39:36 -0400 Victor.Taylor@......... writes: >What ever! Along with the layman physicists, the layman geological >seismologists, and don't forget the prospector, as well others in the >commercial trade, and the technicians and engineers who design and >build >these apparatus. Who needs labels, when we have bread boards and >testing and >engineering and measuring, and our neat inter net seismic watch. what >ever >that is. >Later, > >> -----Original Message----- >> From: cranswick@........ [SMTP:cranswick@......... >> Sent: Tuesday, July 13, 1999 3:41 PM >> To: psn-l@.............. >> Cc: eqip-l@....... >> Subject: Re: EqIP Interim Meeting >> >> John- >> >> > I also mentioned the Public Seismic Network. This is an informal >> > group of mostly non-seismologists interested in seismology to >> > the extent that many run their own seismic stations. >> >> I would label members of the Public Seismic Network as "amateur >> seismologists". I >> think it is difficult to be as involved in seismology to the extent >of >> operating >> ones own seismic station and be a "non-seismologist". >> -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) >> >> 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) Subject: Re: Suggestions anyone? From: barry lotz gbl@....... Date: Tue, 13 Jul 1999 22:23:43 -0700 Raul Construction of house slabs on grade have had problems for years with vapor coming thru the slab and blistering vinyl flooring. I suspect this is a similar situation if there is a water source outside. There are coatings available at hardware stores for concrete but they are being applied to the wrong side of the concrete. They would work better on the source side. It is worth a try though. You may need a descecent(spelling?) to keep the humidity down. Barry Raul Alvarez wrote: > Hi All, > > Started working on a seismo vault here. Plans are to use an old, but > still water tight, cistern that was on the property when we purchased it > > some five years ago. The cistern is 4 feet wide, 8 feet long and 5 feet > > high. The top is about 2 feet below grade. Seems like it would make > a great seismo vault. > My guess about it still being water tight is that it was mostly full of > water but the outside ground is very dry. Since I pumped it out, water > has > not re-accumulated. > > My questions are: I want to be sure it will stay dry. What, if any, > paint > could be used to seal it from the inside? > Also, after being in it a while, getting the last of the water and silt > out, > I got to thinking about the effects of the echoes created in such a box, > > and how they may affect a seismo. > Any suggestions, comments ??? > > Raul > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Suggestions anyone? From: meredith lamb psnseismograph52@.......... Date: Tue, 13 Jul 1999 23:31:08 -0600 Raul Alvarez wrote: > Hi All, > > Started working on a seismo vault here. Plans are to use an old, but > still water tight, cistern that was on the property when we purchased it > some five years ago. The cistern is 4 feet wide, 8 feet long and 5 feet > high. The top is about 2 feet below grade. Seems like it would make > a great seismo vault. > My guess about it still being water tight is that it was mostly full of > water but the outside ground is very dry. Since I pumped it out, water > hasnot re-accumulated. > > My questions are: I want to be sure it will stay dry. What, if any, > paintcould be used to seal it from the inside? > Also, after being in it a while, getting the last of the water and silt > out,I got to thinking about the effects of the echoes created in such a > box, > and how they may affect a seismo. > Any suggestions, comments ??? > > Raul > Hi Raul, Sounds like you have indeed struck "gold", as far as a vault. If there is any cracks, a fast cure concrete usually works fine. Of course, if possible, some kind of drainage sump pump would be necessary to prevent equipment damage in the future. You didn't mention the access, which is the likely cause of the water entrance...it would have to be built up with some water proof roof and/or more concrete I expect. I built up my crawl space entrance afew years back with concrete. Being as the new layer of concrete probably won't adhere very well with the old concrete, I applied a layer of black thick plastic type water repellent on in the area....don't remember the exact brand but its normally used to cover concrete driveways, roofs. My crawlspace entrance is covered with a pivoting joint cover. I also used rubber weather stripping between the cover and the concrete. The cover also has air vents on the south side, away from the prevailing northwest weather circulation pattern. Its also heavy enough that the winds don't "lift" it, and slam it around. The only concrete I've ever painted, was my cinder block garage...which had several layers of unknown brand paint, over some 50 odd years. After wire brushing existing paint separations, peelings, and filling of minor gaps, I used a brand called CongoPro. Its a mixture of acrylic and latex. Its been on two years and except for the very bottom edge contact with water, it seems to adhere better than most paints I've ever ran across. This is on the outside of the garage of course. I've even contemplated the inside, but as ugly grey as it is, I figure the air movement helps keep the inside dry, and any paint may actually weaken the concrete, if water gets in the blocks. Solid concrete could be different, and may well work fine with paint on it. Hope the concrete is not powdering with its ? age. Outside of the above...is your vertical milling machine working since acquisition? Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Suggestions anyone for waterproofing From: "Charles R. Patton" charles.r.patton@........ Date: Tue, 13 Jul 1999 23:30:32 -0700 Over 10 years ago we had a concrete fountain in the front yard. We used pool paint that we bought at a pool supply company. It used a rubber base that used a chlorinated solvent (Tri-chlor as I recall). Nasty solvent, but a great paint for continuous contact with water. (If you use this in a closed space, be sure to provide lots of ventilation =96= the solvent is not good on the heart, lungs, and brain.) It adheres to the concrete great, and is not bothered about being below water permanently (It lasted over 10 or 15 years in direct sunlight before we re-painted, so in a shielded area, I would expect longer than that. And even then it seemed to be watertight, it just looked a bit chalky on the surface.) Such paints are probably still available for pool use, so I would try those. The other solution is to do what is done for spas and tile shower stalls, and that is to hot mop asphalt on the floor and walls. It=92s thick, waterproof, and basically remains a bit flexible for years =96 i.e., it stays tacky for a long time which is an advantage in not cracking and leaking, but a disadvantage if you have to walk on it. You=92d have to lay down walkways of wood or tile after sealing the cistern (or keep a pair of boots near the entrance just for work in the cistern.) Just a couple of thoughts. Charles R. Patton _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Questions about arrays From: angel rodriguez angel@............ Date: Wed, 14 Jul 1999 09:32:45 -0500 Hi all, I Hare been working on several new ideas to make my station more useful to Nome and was going to install a network of several senors 30 km apart to be able to lace small local events with just my station. I was going to have Over the weekend some mention that an array might be better not only for local event but that I could also locate regional events quite well and that the array was much smaller maybe even within a 1 km radius. Can any one shed some light on this idea, can it be done with the kind of stuff we use? I have several Marks L4C's I was planning to use. Is there anything published that I can get my hands on. Any URL's? My other question is does anyone one know of the Chinese company that make broad band sensors and how to get hold of them. Thanks, Angel _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Questions about arrays From: John Hernlund hernlund@....... Date: Wed, 14 Jul 1999 08:20:38 -0700 (MST) On Wed, 14 Jul 1999, angel rodriguez wrote: > I Have been working on several new ideas to make my station more useful > to Nome and was going to install a network of several senors 30 km > apart to be able > to lace small local events with just my station. I was going to have > Over the weekend > some mention that an array might be better not only for local event > but that I could also locate regional events quite well and that the > array was much smaller maybe even within a 1 km radius. Can any one > shed some light on this idea, can it be done with the kind of stuff we > use? I have several Marks L4C's I was planning to use. Is there > anything published that I can get my hands on. Any URL's? Arrays have a lot of power, even if the instruments are not broadband. They are usually constructed to study the lithosphere and upper mantle directly below the array, but more uses have been employed as people tinker with the data. There is a ton of literature on this stuff, because everyone from the oil industry to huge multi-million dollar scientific projects uses them. To get a good array going for locating local events you should have at least three of them in a triangular arrangement. Being precisely geometrical with the arrangement is not necessary, because the analysis can handle any general location. With five sensors, making a large "X" shape with a sensor located in the middle is a good arrangment. If, on the other hand, you want to study a specific line in the Earth then you just line them up along it. You will need separate recording stations each timed using something accessible to each (eg. GPS). The most widely used devices for arrays are part of the PASSCAL array (Passive Array for the Seismic Study of the Continental Lithosphere or something like that) which are owned and distributed by the IRIS consortium, of which just about every major university is a member (www.iris.edu). They have a nice compact system of broadband sensors, programmable digital recorders, and power supplies like solar panels. They probably have tons of stuff on installing and operating these types of arrays. > My other question is does anyone one know of the Chinese > company that make broad band sensors and how to get hold of them. No...never heard of them. John Hernlund E-mail: hernlund@....... WWW: http://www.public.asu.edu/~hernlund/ ****************************************************************************** _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Questions about arrays From: John Lahr lahr@................... Date: Wed, 14 Jul 1999 09:44:18 -0600 (MDT) Hi Angel, The best way to locate local events is with a distribution of 1 Hz geophones within and around the region of interest. For events outside of the array, the location accuracy deteriorates quickly. A 1-km array could be used to get the phase velocity and azimuth of approach of seismic signals, but would not, in my opinion, be the first choice for locating regional events. The sample rate would need to be quite high as would the relative timing accuracy. Cheers, JCLahr _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re[2]: Questions about arrays From: angel rodriguez angel@............ Date: Wed, 14 Jul 1999 10:51:52 -0500 Hello Angel, JH> Arrays have a lot of power, even if the instruments are not broadband. JH> They are usually constructed to study the lithosphere and upper mantle JH> directly below the array, but more uses have been employed as people tinker JH> with the data. There is a ton of literature on this stuff, because everyone JH> from the oil industry to huge multi-million dollar scientific projects uses JH> them. To get a good array going for locating local events you should have at JH> least three of them in a triangular arrangement. Being precisely geometrical JH> with the arrangement is not necessary, because the analysis can handle any JH> general location. With five sensors, making a large "X" shape with a sensor JH> located in the middle is a good arrangment. If, on the other hand, you want JH> to study a specific line in the Earth then you just line them up along it. JH> You will need separate recording stations each timed using something JH> accessible to each (eg. GPS). The most widely used devices for arrays are JH> part of the PASSCAL array (Passive Array for the Seismic Study of the JH> Continental Lithosphere or something like that) which are owned and JH> distributed by the IRIS consortium, of which just about every major university JH> is a member (www.iris.edu). They have a nice compact system of broadband JH> sensors, programmable digital recorders, and power supplies like solar panels. JH> They probably have tons of stuff on installing and operating these types of JH> arrays. Hi John, I have found two URL's in the last hour and one of them is nice. why would each station need it's own GPS if I could get the signals from the sensor to a main station either using a VCO a transmitter/receiver and Larry's demodulator then the three or five stations into one of Larry's AtoD and sdr for later processing?? To keep the power requirments down at the remote stations it would be nice to have as little electronics as possible. If the costs and complexity of the telemetry stuff is tooo much I might be willing to lay cable to each of the remote station. It would be nice to keep this experiment as simple as possible and still get usefull data. http://www-seismo.hannover.bgr.de/geress.html http://www.geology.smu.edu/~hayward/Txar/index.html Best regards, Angel mailto:angel@............ _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: timing From: John Lahr lahr@................... Date: Wed, 14 Jul 1999 11:22:29 -0600 (MDT) Angel, If you have central recording, then each station would not need to have GPS time. Good luck with your project! JCLahr _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Re[2]: Questions about arrays From: John Hernlund hernlund@....... Date: Wed, 14 Jul 1999 11:17:50 -0700 (MST) On Wed, 14 Jul 1999, angel rodriguez wrote: > I have found two URL's in the last hour and one of them is nice. why > would each station need it's own GPS if I could get the signals from > the sensor to a main station either using a VCO a transmitter/receiver > and Larry's demodulator then the three or five stations into one of Larry's > AtoD and sdr for later processing?? You could try this, but there will likely be some processing and other time sensitive operations done at the recording site if you want to transmit digital data. If you are transmitting analog data directly from the sensor then keeping time at the central station is okay, but keep in mind that there may be time delays in this process as well that could possibly affect the accuracy. For an array time-keeping is extremely important if anything is to be done with the data. I think it is safer to have each site keep time (that is what I would do). This also makes each station more independent... > To keep the power requirments down at > the remote stations it would be nice to have as little electronics as > possible. > If the costs and complexity of the telemetry stuff is tooo much I might > be willing to lay cable to each of the remote station. It would be > nice to keep this experiment as simple as possible and still get > usefull data. Angel, You will run into a whole lot more complexities and problems by laying cables (and probably expense if you are doing things on a kilometer scale!). The only way to avoid signal loss or distortion using cables is by digitizing at the sending end of the line, which brings you back to the same situation as before. This is a classic problem which has been aching for a better solution for over 100 years. Contrary to popular belief, electric signals do not simply zip from one end of a cable to the other at the speed of light with arbitrary accuracy. This is due to the finite resistance, capactitance and inductane in metal wires due to intrinsic defects in chemistry that make it non-ideal. The actual equation describing the transmission of a signal is given by the transmission line equation, which is a second order differential equation similar to the one for the damped seismometer. To transmit signals you have to set the unit capacitance and inductance of your line to a specified value using actual electronic rigs. This is the reason why we can't build phone modems faster than 56Kbps. The unit capacitance and inductance is set to frequencies corresponding to the human voice... The only way around this problem is to use fiber optics, which is becoming less expensive over time but is still costly to install. John Hernlund E-mail: hernlund@....... WWW: http://www.public.asu.edu/~hernlund/ ****************************************************************************** _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Questions about arrays From: Arie Verveer ajbv@............ Date: Thu, 15 Jul 1999 09:14:24 +0800 Hi, 2 cents worth, There are many seismic arrays available via the Automatic Data Request Manager, (AutoDrm). If you are interested see http://www.iinet.net.au/~ajbv Also http://orfeus.knmi.nl/ Also http://www.pidc.org/networksbox/Network.html I have, on occasions, downloaded the seismic array data for a specific time period. Its easily done. Arie _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: FW: Surplus seismograph From: Edward Cranswick cranswick@........ Date: Wed, 14 Jul 1999 21:15:44 -0600 Marchal- Your email to USGS:Ask-A-Geologist about how to obtain a long-period seismograph was relayed to me by the USGS. I would have recommended that you check out the Public Seismic Network (PSN) Redword City website but I have already seen you exhanging email with PSN members on the PSN listserver. So I presume you have by now had your original questions answered. Good luck with the Lehman seismograph that you are building. Do you know Kees Verbeek? (see below) NAME: Kees Verbeek (12) E-MAIL: kverb@........ TOWN/CITY: Eindhoven STATE/PROV: N-Brabant COUNTRY: Netherlands LAT/LONG: 51.26 N 5.30 E CH1: Bosch mecanical (1908) 24- hours a day since 1994 (no filter just damped (air) receive most quakes 5.5 and above home-made copy DRUM: mecanical rotating drum (smoked paper) GND TYPE: Deep soft soils COMMENTS: planning to make a portable seismograph (collecting info!) -Edward "Scott A. Minor" wrote: > Dear Ed: > Thanks for helping me out on this! Please respond to the inquirer ASAP > (by this Friday at the latest), and please Cc: your answer to > answers@................... and sminor@......... > > Thanks again, > Scott > _____________________________________ > Scott A. Minor > U.S. Geological Survey > National Cooperative Geologic Mapping Team > Box 25046, MS 913 > Denver, CO 80225 > > 303-236-0303 (office) > 303-236-0214 (FAX) > sminor@........ > _____________________________________ > > -----Original Message----- > From: Marchal van Lare [SMTP:vanlare@............... > Sent: Tuesday, July 13, 1999 9:44 AM > To: Ask-A-Geologist > Subject: Surplus seismograph > > Hello, > > More than a year ago I started recording earthquakes with three 4.5 Hz Mark > Products geophones. These geophones are only sensitive to local earthquake > activity. > The problem is, I am missing the large distant earthquakes. To be able to > detect the larger distant events I will need a long period seismograph. > I tried to build my own device, but I couldn't get the right materials and > I'm not a great technician. > My question is, do you know of any source where I can buy a good working > seismograph and/or parts? Or may be you know where I can find a source of > old or used surplus long period seismographs? > I am looking forward to hear from you. > Best regards, > > Marchal van Lare > -Nieuwvliet, The Netherlands -- 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) Subject: Re: Questions about arrays From: barry lotz gbl@....... Date: Wed, 14 Jul 1999 22:03:10 -0700 John et al How would wireless work? I would like to link several (at least one )with my house. I was considering a distance of several miles. I was thinking of using a cell phone which was part of the remote station. It would be nice to use the internet to get ones data. Does anyone know where I can find out about using the internet for sensor monitoring? Internet sensor monitorring for dummys? :) Regards Barry John Hernlund wrote: > Angel, > You will run into a whole lot more complexities and problems by laying > cables (and probably expense if you are doing things on a kilometer scale!). > The only way to avoid signal loss or distortion using cables is by digitizing > at the sending end of the line, which brings you back to the same situation as > before. This is a classic problem which has been aching for a better solution > for over 100 years. Contrary to popular belief, electric signals do not > simply zip from one end of a cable to the other at the speed of light with > arbitrary accuracy. This is due to the finite resistance, capactitance and > inductane in metal wires due to intrinsic defects in chemistry that make it > non-ideal. The actual equation describing the transmission of a signal is > given by the transmission line equation, which is a second order differential > equation similar to the one for the damped seismometer. To transmit signals > you have to set the unit capacitance and inductance of your line to a > specified value using actual electronic rigs. This is the reason why we can't > build phone modems faster than 56Kbps. The unit capacitance and inductance is > set to frequencies corresponding to the human voice... The only way around > this problem is to use fiber optics, which is becoming less expensive over > time but is still costly to install. > > John Hernlund _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: [Fwd: Update--Proposed Earthquake Networks Upgrade] From: Edward Cranswick cranswick@........ Date: Wed, 14 Jul 1999 23:03:13 -0600 better late than never . . . -- 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". Hi Everybody, I thought you might be interested in this news about efforts to secure funding to upgrade seismic networks across the country. Tony =========================================== --Federal Computer Week (4/26) Hill backs earthquake systems BY L. SCOTT TILLETT (scott_tillett@........ The House of Representatives last week passed a bill that allocates more than $200 million in fiscal 2000 for new computer projects to monitor and analyze earthquake activity, including systems that would provide early warnings to help save lives. The Earthquake Hazards Reduction Authorization Act, which the House overwhelmingly approved 414-3, would earmark more than $170 million for the U.S. Geological Survey to modernize its existing earthquake-monitoring systems during the next five years. The bill also authorizes the National Science Foundation to spend almost $82 million for a five-year project to build a computer network to connect earthquake research centers across the nation. If the bill becomes law, congressional appropriations committees will consider it in current and future funding deliberations. "Earthquakes may be inevitable, but catastrophic losses in life and property can be avoided if we use science and technology to help communities prepare," Rep. James Sensenbrenner Jr. (R-Wis.), House Science Committee chairman, said in a prepared statement. "This legislation represents a sensible, long-term investment that will pay for itself many times over in saved lives and reduced property losses." According to some estimates, earthquakes cost the U.S. economy about $4.4 billion each year. But costs can rise dramatically when strong earthquakes hit metropolitan areas, such as the 1994 Northridge, Calif., quake, which caused an estimated $40 billion in property damage. The money authorized by the bill would help the USGS update its network of seismographs, which detect earthquakes, and strong-motion detectors, which monitor how buildings and other structures react to earthquakes. The agency now operates about 1,900 seismographs and about 840 strong-motion detectors. When an earthquake occurs, the sensors -- placed in fields, on bridges and in some buildings -- pick up the tremors. Most of the devices send the information via radio or telecommunications lines to computer systems at USGS offices or select universities, which then analyze the strength of the earthquake. If a quake is strong, USGS informs federal and local emergency services of its location and magnitude. Computer systems also analyze other effects, and USGS uses this information to plan for future quakes, according to John Unger, a USGS seismologist. But the seismographic system is aging, and USGS officials say they need additional money to fund a digital program, called the Advanced Seismic Research and Monitoring System, to replace devices in the field. The upgrade would enable digital devices to collect more detailed information. The analog devices now used detect only vertical motion and often do not detect slight movements, Unger said. USGS also would put the money toward more high-powered software applications to analyze earthquake information. With more information, as well as more rapid access to that information, emergency management officials would be able to almost instantly pinpoint areas where the most violent shaking from an earthquake has occurred. This can allow officials to send help more quickly where it is needed most, Unger said. Typically, the epicenter of an earthquake is not the area that experiences the strongest shaking, Unger said. Sometimes the strongest effects are felt a few miles away. "I'm very excited" about the additional funds, Unger said. "I'd be more excited if it were an appropriation. We've just pushed the limits as far as where we can go with the systems that we have." Susan Tubbesing, executive director of the Earthquake Engineering Research Institute, praised the passage of the bill, noting especially the bill's focus on giving the NSF money to create a network to connect earthquake research centers. NSF's project, called the Network for Earthquake Engineering Simulation (NEES), will upgrade hardware and software at earthquake engineering research centers nationwide and link those centers via one network. Researchers will be able to more easily share data such as computer-constructed designs for earthquake-resistant structures. Building a network for researchers will allow greater participation in designing structures to withstand earthquakes, Tubbesing said. However, more needs to be done to encourage all levels of government, academia and industry to put the more precise information to practical use, said Lisa Warnecke, a Syracuse, N.Y.-based geographic information consultant. For example, town zoning officials could use the information to pinpoint fault lines and to develop stricter building codes near those areas, she said. "Are we doing enough on the side of mitigating and taking advantage of that information?" Warnecke asked. ************************************ Anthony J. Crone Geologic Hazards Team Research Geologist U.S. Geological Survey MS 966, Box 25046 Denver, Colorado 80225-0046 U.S.A. ------------------------------------ /\ phone: (303) 273-8591 /\ /\/^^\/\ FAX: (303) 273-8600 /^^\/ /^^^/^^\/\ e-mail: crone@................... / / /^^^/^^^/ \ ************************************* Subject: Wireless Telemetry From: Tom Genereaux entropy@.............. Date: Thu, 15 Jul 1999 00:09:26 -0500 Barry - Depending on the path, you might want to look into some of the ISM (Industrial, Scientific, Monitoring(?) (it's late!)) Part 15 devices. These don't require a license, and the cost is less than a cell modem. Actually - let me think about this a bit - I need to do some back-of-the-envelope calculations about data rates, radio costs, and so on. The real problem with using cell modem is the on-air cost, along with very low data rates. Tom G. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Questions about arrays From: wizard@......... (Rick Jerome) Date: Thu, 15 Jul 1999 04:10:10 -0700 We use license free 915 Mhz telemetry units from Automation Electronics to control remote tank and pump sites at work. They are good for about 5 miles line of site and provide contact closure and analog sensor inputs. They are spread spectrum and we have had no problems with them. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: [Fwd: Update--Proposed Earthquake Networks Upgrade] From: meredith lamb psnseismograph52@.......... Date: Thu, 15 Jul 1999 00:37:14 -0600 Edward Cranswick wrote: > better late than never . . . > > -- > 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: Update--Proposed Earthquake Networks Upgrade > Date: Mon, 3 May 1999 13:33:27 -0600 > From: Tony Crone > To: geo_haz_team@.................. > > Hi Everybody, > > I thought you might be interested in this news about efforts to secure > funding to upgrade seismic networks across the country. > > Tony > =========================================== > --Federal Computer Week (4/26) > > Hill backs earthquake systems > > BY L. SCOTT TILLETT (scott_tillett@........ > > The House of Representatives last week passed a bill that allocates more > than $200 million in fiscal 2000 for new computer projects to monitor and > analyze earthquake activity, including systems that would provide early > warnings to help save lives. > Good news Edward....but I don't see funding for personnel, or is that buried deep somewhere therein? Hope it really comes about, you people deserve the best. Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: RE: Seismograph From: "The Brewers" mbrewer@...... Date: Thu, 15 Jul 1999 22:39:26 -0300 Bob, Thank you for your comments. Your first comment is very interesting. The boom is a pendulum. In order for it to be in balance as a "gate" it must first be in balance as a vertical pendulum. I first found the vertical balance point of the entire boom assembly. I then suspended the assembly in the Lehman "gate" position. I marked the suspension point and cut a shallow, vertical groove in the face of the support. I adjusted the position of the seismometer until the boom centred. I find very little drift in the two horizontal instruments. I may have to adjust the physical instruments once every four to six months. The magnitude correction in Winquake needs to be adjusted a little more often, but not by much. As to your second point, I cannot say very much more, except that a vertical knife edge support of a balanced pendulum eliminates any source of noise from vertical displacement. Martin Brewer _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: seismicity maps From: robert barns 75612.2635@.............. Date: Sat, 17 Jul 1999 11:16:41 -0400 Hi gang, A friend needs maps of 'quake activity in selected regions around Bulgaria and adjacent countries. He would like to be able to specify the= area. For example, a 500 mi. radius around a particular city. Is there some place on the internet for this? He is trying to avoid th= e necessity of putting dots on a map from tabular data. Bob Barns _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Motorola Encore GPS From: Greg ghost@............. Date: Sat, 17 Jul 1999 12:29:35 -0700 If anyone out there is tempted to buy the GPS setup Larry is selling, I have something else you might want to consider. The manual for the reciever and xntp3 have the same ASCII string for time. In other words it might cheap and somewhat easy to set up a stratum 1 network time server with Linux (the cheapest part) on your home LAN. I don't know how well that would work with SDR though. Maybe get two? :) Some of the details are: Driver type 20 Generic NMEA GPS Receiver (NMEA) xntp3 (time server software included with most newer Linux CDs) The ASCII string starts out "$GPRMC" URL for xntp3 is http://www.cis.udel.edu/~ntp/ You can get a Linux CD with the newest unofficial version for about $7-8 US from places like CheapBytes, InfoMagic and Linux Mall. The time server software is most likely on the CD. There's also a driver for the 1 PPS signal for atomic clocks and other receivers. You might be able to write a driver (simpler than a kernel driver) for one of those $100 WWVB receivers. 'just thought someone might be interested. ,Greg _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Murphys Law? From: barry lotz gbl@....... Date: Sun, 18 Jul 1999 22:15:32 -0700 Well, just as the Kermadec S wave came in I accidently shorted two wires and got a transient. Then a little while later I saw the sensors all oscillating @ ~17 sec period and I thought I had a system oscillation and I stopped the power briefly --opps! they were surface waves. I pieced the event together reasonably well. Live and learn :) Barry _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: seismicity maps From: John Hernlund hernlund@....... Date: Mon, 19 Jul 1999 08:38:06 -0700 (MST) On Sat, 17 Jul 1999, robert barns wrote: > A friend needs maps of 'quake activity in selected regions around > Bulgaria and adjacent countries. He would like to be able to specify the > area. For example, a 500 mi. radius around a particular city. > Is there some place on the internet for this? He is trying to avoid the > necessity of putting dots on a map from tabular data. > Bob Barns Bob, I am working on making a web based program that will do this and a number of other tasks, but our SysAdmin is extremely worried about security. A form would be filled out on a page of the min and max lat and lon. A cgi script will then call a perl script that will build a GMT (Generic Mapping Tools) macro file that, when executed, will produce a postscript file that can then be converted to .gif format and returned to the browser. I am still working on finding a good color postscript to gif translator for unix (Solaris OS), so if anybody knows one, please let me know. The data will be taken from the available databases on the www. I would also like to have this program compute b-values and make a N-S and E-W cross section of the data, but that is further down the road... For now, if your friend could get the area(s) he is interested in displaying to me then I can make a plot for him. Just let me know! John Hernlund E-mail: hernlund@....... WWW: http://www.public.asu.edu/~hernlund/ ****************************************************************************** _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: TSR Y2K fixes From: angel rodriguez angel@............ Date: Mon, 19 Jul 1999 12:11:13 -0500 Hi all, Here is a URL with some Y2K TSR fixes. I'm going to try some of them this afternoon. Thought they might help some other machines. http://www.mitre.org/research/cots/PATCH.html angel _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Forwarded question From: Greg ghost@............. Date: Mon, 19 Jul 1999 12:23:31 -0700 Someone read my little FAQ on Geophones and assumed I knew something about them. I need some help with an answer to his question, please. "I've been looking on the net for geophones, and I keep seeing a spec I don't understand. What is the spurious frequency of a geophone?" I'm thinking it's something like maximum usable frequency? Maybe? I think he got the term from the GeoSpace web pages. Thanks in advance, Greg _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: seismicity maps From: John Lahr lahr@................... Date: Mon, 19 Jul 1999 13:54:48 -0600 (MDT) Hi Bob, I just found out that the USGS NEIC page can generate either a listing of earthquakes or a map! Take a look at: http://wwwneic.cr.usgs.gov/neis/epic/epic_rect.html Cheers, JCLahr _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Forwarded question From: Doug Crice dcrice@............ Date: Mon, 19 Jul 1999 14:42:34 -0700 Greg wrote: > > "I've been looking on the net for geophones, and I keep seeing a spec I > don't understand. What is the spurious frequency of a geophone?" > A geophone is of course a pendulum with a natural frequency set by the spring constants, etc. In the illustrative drawings, you only see a mass and a spring. In real life, there are other elements of the suspension system that hold the moving coil in position laterally and such. And since the spring is a flat coil, may have other modes of flexure. It turns out that these other elements also create other pendulums with their own resonant frequencies, typically much higher because the spring constants are much stiffer. The other resonant frequencies are called spurious resonances. For example, if you tap the side of a vertical geophone, the mass will shake back and forth (as well as the desired direction) at some high frequency. Back in the old days, nobody cared about these spurious resonances, because seismic reflection crews only recorded data well below 100 Hz. In the last couple of decades, it became stylish to record higher frequencies because it gave you much better resolution of the geologic structure--you could see thinner layers. The curves always showed geophones as flat above the natural frequency, but in reality, there were often large peaks in that band. Geophysicists discovered the existence of these spurious resonances, and modern geophones addressed the problem by improved designs and then by specifying where spurious resonances might be found in the response curve. They can't be eliminated, but they can be pushed up in frequency until we still don't care. For example, for high resolution reflection, you might want to recover data from 28 to 500 Hz, and so you would want the spurious frequency up around 800 or so. None of these will matter for earthquake recording, since those kinds of frequencies only travel a few hundred feet at best, but you might have local noise sources in that frequency range. A reasonable anti-alias filter will eliminate them. -- 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) Subject: Dominica PSN data used by NEIS From: Edward Cranswick cranswick@........ Date: Mon, 19 Jul 1999 16:44:46 -0600 PSN members- Congratulations to the Dominica PSN whose P-wave phase pick (Station PSDMA, the immediately following P indentifies the phase as a P-wave) for a regional Caribbean earthquake they recorded was included in the NEIS location: HY19990711 115116.40 16.457N 60.027W 61.2D0.90 74 92 E 0.26 2.80 4.79 4.7 24 5.2MDTRN L 93.67 0.006.27E+00 3.67 0.003.64E+00 0.00 0.000.00E+00 C MD 5.2 (TRN). Felt on Guadeloupe and Martinique. P DBCT iP 115145.22 0.4 1.74 227.4 P PSDMAP 115144.70 -0.4 1.77 226.7 P DPMT eP 115145.15 0.0 1.77 227.8 P BPA eP 115144.40 -1.9 1.85 288.7 P ANG iPc 115144.64 -1.8 1.86 292.1 P CPB eP 115147.50 -2.1 2.08 304.6 P NEV eP 115151.42 -4.4X 2.53 285.8 .. . . (From which can be accessed from "Current Hypocenter Data. EHDF format" ) -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) Subject: Re: Forwarded question From: Greg ghost@............. Date: Mon, 19 Jul 1999 22:37:35 -0700 Doug Crice wrote: > For example, if you tap the side of a vertical geophone, the mass will > shake back and forth (as well as the desired direction) at some high > frequency. Thanks for the response. I going to add that question to the FAQ soon. I don't know what set this off, but the I just got another one I can't answer. I gonna refer him to the list. I think you might be interested in the subject. Antique instruments. Thanks again, Greg _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: suspension resonances From: S-T Morrissey sean@........... Date: Wed, 21 Jul 1999 13:15:02 -0500 (CDT) Regarding suspension resonances in seismometers: Doug has very nicely explained the origins of these spurious responses. THey are essentially due to the fact that while a spring's behaviour can be carefully described when it extends in the normal direction, when the spring elements move other than in the normal direction, particularly at right angles to the main tension axis, the overall effect is to shorten the spring in a cyclic fashion depending on the geometry involved. The clearest example is with a long coil spring as in long-period vertical or "LaCoste" type suspensions. THe tension of the spring supports the boom and mass, which have a characteristic period determined by the usual equations. But if something causes the center of the spring itself to move laterally, this will raise the mass, and as the spring mass itself oscillates laterally, this spurious resonance will be imparted to the man mass motion. Often, the oscillation of the spring is much weaker than the main suspension behavior, so the large main mass will integrate the spurious resonance into a one-sided deflection of the output. Often this integrated response is WITH IN the passband of the data of interest, and cannot be eliminated. Fortunately, it usually requires significant acceleration to excite it, so is not a problem except for near field events (or noise), where strong-motion sensors are useful for recording true ground motion. A typical example of this is from the old 15-second long period vertical that I am operating as a 600-second VBB in a vault under the stairs of our building; when classes change, the troops romping down the stairs excite the spring resonance, which causes one-sided long-period downward (since the mass is pulled up) bumps in the record. This is one of the reasons that leaf-spring suspensions are used in broadband sensors; the spring has much less mass and is much more rigid than the coil spring, so its resonances are outside the VBB passband of the sensor. For compact vertical sensors, like geophones, they can be a problem for modern digital recording. The manufacturers are usually mum on these; the most notorious are the resonances of the 1-hz vertical L4-C at 16 and 22 hz. THe resonances can easily be found with a shake table, shaking a vertical in a horizontal direction. But a calibration coil can also be used to excite them; with sufficient input the inherent non-linearities of the suspension will cause the resonances to be excited. Since they are a mechanical problem, little can be done other than knowing where they are and narrowing the data passband to aviod them, or possibly specifying the level of acceleration that is needed to excite them. Some efforts at visco-elastic damping have been attempted; we even had a seismometer that was filled with a liquid freon compond to damp them. Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: seismic telemetry From: S-T Morrissey sean@........... Date: Sun, 25 Jul 1999 14:15:33 -0500 (CDT) Barry, You asked about telemetry for a seismic station. This is either a complex problem or a simple solution to getting seismic data from yon to hither, depending on your resources and expectations. The most basic is the double FM analogue telemetry. First, the amplified seismic signal (ground velocity) is used to frequency modulate an audio frequency (the carrier). The standard is to use "center frequencies", (or tones with no data), of 680,1020,1360,1700,2040, 2380, 2720, and 3060 hz. These eight tones can be multiplexed (resistively added together) to fit on a single narrow-band FM radio link or a standard telephone line. The seismic data modulates or changes the frequency of the tones proportional to the amplifier output voltage. Usually + or - 4 volts swings the frequency + or - 125 hz with a VCO (voltage controlled oscillator). At the receiving or data recording end, a "discriminator" does the reverse to recover the seismic data from the FM carrier. This is usually done with a PLL (phased locked loop) that generates a voltage that keeps a local VCO tracking the frequency of the incoming FM data. THe "phase lock" means that the tracking is within a small portion (phase) of a single cycle of the FM carrier. So the tracking voltage is the original seismic signal. If the phase lock is within about 1/20th of a cycle (18 degrees) of the 125hz maximum deviation, the dynamic range is 1:2500, or about 70 db. This is the main limitation of FM telemetry. I won't go onto the details of a VHF or UHF FM radio link. THere are some modern ICs that use frequency synthesizers to greatly simplify the modulation and demodulation, but a commercial low-power link can still cost $500 and up since they are basically handmade. The parts list can't amount to more than $50, but VHF/UHF circuits require an experienced hand. There are probably some ham transceivers that could be used, as well as some commercial units (I have a lead on one for $180 that can be used as either end of a VHF link). But is is too power hungry for long-term battery operation.. And there is the problem of which VHF or UHF frequency to use, and any licensing requirement. Below 0.1 watt does not require a license in some areas and bands; With proper antennae and propagation path, 0.1 watt will go 50 km or more. So if you want to make your own FM telemetry, I can send schematics. THe VCO is pretty basic, with the main complication being the temperature compensation circuit. We have only a 90 hz "guard band" between the highest one carrier can go and the lowest the next up can dip, so temperature wander of the center frequencies needs to be curtailed. The circuit uses the VCO section of the cmos 4046 IC. The discriminator is the complicated circuit. First, it needs to use a narrow band audio filter to recover its carrier from the multiplexed group of tones (unless only a single carrier is used). This is usually a 12-pole tuned bandpass filter consisting of three adjacent narrow bandpass filters. A synthesized or digital comb filter can also be used. Then there is the PLL, usually using the LM565 PLL IC, whose frequency dependent components need to be carefully selected for stability. Then the data voltage has to be recovered and properly scaled, and then at least 4 poles of low pass filtering are needed to clean up the data (removing any low-frequency carrier components (intermodulations) and phase jitter of the PLL loop). I think Larry has a telemetry discriminator that accomplishes most of this. We made over a 100 of them years ago in order to realize the low noise we expected to achieve. I don't know if an FM telemetry system could be could be called inexpensive though. You can make the VCO for $50, but an FM radio link (synthesized transceivers) will cost $400, and a discriminator will run $200 per channel, plus considerations for packaging and power. Regards, Sean-THomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: seismic telemetry From: David Josephson david@............. Date: Sun, 25 Jul 1999 12:36:43 -0700 (PDT) Just a reminder, I still have a pile of GE mobile radios that are ideal for seismic telemetry in the 150 MHz band, and they are free for the taking. (But, you have to come get them at my shop near downtown San Jose). You may also borrow the schematics to copy. They take +12V and have vacuum tube transmitter output stages, but the mobile supply and vacuum tube stages can be removed and the driver output taken direct for about 200 mW of output (sorry, this is not in any frequency band where you can transmit license-free with 100 mW as S-T mentioned). The power requirement is then 10 volts at a few hundred mA. You can however put these in the 2m amateur band and with a no-code technician class license use any power you want in 144-148 MHz so long as your telemetry isn't for work or profit. E-mail me off list if you would like some. -- David Josephson / Josephson Engineering / San Jose CA / david@............. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: seismic telemetry & VBB From: barry lotz gbl@....... Date: Sun, 25 Jul 1999 19:12:41 -0700 Sean Thomas & David Thanks for your response. Does the noise immunity of digital signals still apply at radio frequencies? I was thinking of modems vs transievers. BTW It seems like the VBB that I set up about 10 months ago has reasonably stabilized. That is, the leaf spring is essentially not creeping slowly down. I haven't adjusted it in a month or better. I set up another one about 4 months ago. I'll see if it responds similarily. Regards Barry _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: New event? From: barry lotz gbl@....... Date: Sun, 25 Jul 1999 19:23:14 -0700 I'm getting some surface waves coming in here at ~ 02:20 UTC. I'm not touching anything electronic this time. :) Barrry _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: New event? From: "dave nelson" davenelson39@........... Date: Sun, 25 Jul 1999 21:54:17 PDT hi Barry, prob this event 99/07/26 01:33:16 5.07S 152.00E 33.0 6.1Ms A NEW BRITAIN REGION, P.N.G. Cheers Dave >From: barry lotz >Reply-To: PSN-L Mailing List >To: PSN-L Mailing List >Subject: New event? >Date: Sun, 25 Jul 1999 19:23:14 -0700 > >I'm getting some surface waves coming in here at ~ 02:20 UTC. I'm not >touching anything electronic this time. :) >Barrry > > >_____________________________________________________________________ > >Public Seismic Network Mailing List (PSN-L) > >To leave this list email listserver@.............. with the body of the >message: leave PSN-L _______________________________________________________________ Get Free Email and Do More On The Web. Visit http://www.msn.com _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: seismic telemetry & VBB From: jmhannon@.................... Date: Mon, 26 Jul 1999 07:19:14 -0500 Barry, The answer to to your question is yes and no. When you add noise to an analog signal the quality of the signal gradually gets worse the more noise you add. With a digital signal via a modem the same sort of thing happens but since the noise can affect any bit of you data there can end up being large errors in the value represented by the data for even a small amount of noise. The big advantage of digital communications is that it is possible to add error detection and correction to the data being sent. You end up sending more data to allow for correcting errors but the net result is an almost error free signal. Jim Hannon barry lotz on 07/25/99 09:12:41 PM Please respond to PSN-L Mailing List To: PSN-L Mailing List cc: Subject: Re: seismic telemetry & VBB Sean Thomas & David Thanks for your response. Does the noise immunity of digital signals still apply at radio frequencies? I was thinking of modems vs transievers. Regards Barry _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Old equipment From: Greg ghost@............. Date: Mon, 26 Jul 1999 11:59:07 -0700 I got another email from my Geophone FAQ. Again, I can't really answer the question. I'd appreciate any thoughts for the reply and the FAQ. I asked the author to join the list, but I don't think that happened yet? I have a pair made of brass top and bottom plates seperated by what looks like an iron section. Ther are about 3 1/2" in diameter and 1 3/16" thick ( each section being 3/8"). They are marked "GEOPHONE Joseph G Pollard Co. New Hyde Park, N.Y. 1863". My questions are : 1. Could they really be that old? 2. If they are, what were their uses during that period ? I've seen the antique Chinese "instrument" with the balls that fall out of the dragon mouths, but how far back does something like this go? I know that there have been some large earthquakes "recorded" throughout history, but I thought that most of the really old ones are estimated by damages and people's guesses. The list has been a little quiet lately hasn't it? As always, thanks for responses, Greg _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Old equipment From: Steve Hammond shammon1@............. Date: Tue, 27 Jul 1999 06:52:33 -0700 Greg, the Chinese "instrument" is the Seismoscope built by Chinese scholar Chang-Heng about 132A.D. I found the discription of the Geophone even more interesting. It reminded me of a pre WWI deveive I read about. Here is the text description. Source: A.S. EVE and D.A. Keys, 1938, Applied Geophysics, Cambridge at the University Press Page 230 Seismic Methods "Thus geophones were used in the War, and may be used in mines for detecting the direction of such disturbances as blasting or the noise of a pick in tunnelling. Two geophones are employed of similar size and construction, in each of which an iron cylinder floats on mercury, while above the iron is a layer of enclosed air connected through a small hole with a rubber tube leading to the observer's ear. One geophone is thus connected to the right ear, the other to the left. The shock comming through the ground displaces the case of the geophone, while the inertia of the mercury and iron tends to hold them relatively at rest. Hence, the air is driven in rhythmic puffs through the holes and tubes to the observer's ears, and he hears the sound in a quite natural fashion. The remarkable physiological phenomenon of "binaural hearing" now comes into play." What has got my attention is that you did not describe any electrical connections and you mentioned an iron section. Is there a coil in the Pollard Geophone? Or could it be a orignial pre WWI geophone? Regards, Greg wrote: > > I got another email from my Geophone FAQ. Again, I can't really answer > the question. I'd appreciate any thoughts for the reply and the FAQ. I > asked the author to join the list, but I don't think that happened yet? > > > I have a pair made of brass top and bottom > plates seperated by what looks like an iron > section. Ther are about 3 1/2" in diameter > and 1 3/16" thick ( each section being 3/8"). > > They are marked "GEOPHONE Joseph G Pollard > Co. New Hyde Park, N.Y. 1863". > > My questions are : > > 1. Could they really be that old? > > 2. If they are, what were their uses during > that period ? > > > I've seen the antique Chinese "instrument" with the balls that fall out > of the dragon mouths, but how far back does something like this go? I > know that there have been some large earthquakes "recorded" throughout > history, but I thought that most of the really old ones are estimated by > damages and people's guesses. > > The list has been a little quiet lately hasn't it? > > As always, thanks for responses, > 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) Subject: Re: Old equipment From: Greg ghost@............. Date: Tue, 27 Jul 1999 09:11:28 -0700 Steve Hammond wrote: > Source: A.S. EVE and D.A. Keys, 1938, Applied Geophysics, Cambridge at > the University Press Page 230 > > Seismic Methods "Thus geophones were used in the War, and may be used > in mines for detecting the direction of such disturbances as blasting or > the noise of a pick in tunnelling. Two geophones are employed of similar > size and construction, in each of which an iron cylinder floats on > mercury, while above the iron is a layer of enclosed air connected Neat. I wonder if anyone ever got mercury in their ears? > What has got my attention is that you did not describe any electrical > connections and you mentioned an iron section. Is there a coil in the > Pollard Geophone? Or could it be a orignial pre WWI geophone? The description doesn't sound too far off. What I qouted is all that I have right now. I asked for more information. When/if I get it I'll forward that to the list also. Thanks for looking into it, Greg _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Old equipment From: David & Betti Chase chase@........ Date: Wed, 28 Jul 1999 20:56:43 -0400 Hello, I originally posted the query about the geo phones. If you have an interest , there is a oicture at the following address: http://www.mint.net/~chase/geophone.jpg David Chase Steve Hammond wrote: > > Greg, the Chinese "instrument" is the Seismoscope built by Chinese > scholar Chang-Heng about 132A.D. I found the discription of the Geophone > even more interesting. It reminded me of a pre WWI deveive I read about. > Here is the text description. > > Source: A.S. EVE and D.A. Keys, 1938, Applied Geophysics, Cambridge at > the University Press Page 230 > > Seismic Methods "Thus geophones were used in the War, and may be used > in mines for detecting the direction of such disturbances as blasting or > the noise of a pick in tunnelling. Two geophones are employed of similar > size and construction, in each of which an iron cylinder floats on > mercury, while above the iron is a layer of enclosed air connected > through a small hole with a rubber tube leading to the observer's ear. > One geophone is thus connected to the right ear, the other to the left. > The shock comming through the ground displaces the case of the geophone, > while the inertia of the mercury and iron tends to hold them relatively > at rest. Hence, the air is driven in rhythmic puffs through the holes > and tubes to the observer's ears, and he hears the sound in a quite > natural fashion. The remarkable physiological phenomenon of "binaural > hearing" now comes into play." > > What has got my attention is that you did not describe any electrical > connections and you mentioned an iron section. Is there a coil in the > Pollard Geophone? Or could it be a orignial pre WWI geophone? > > Regards, > > > Greg wrote: > > > > I got another email from my Geophone FAQ. Again, I can't really answer > > the question. I'd appreciate any thoughts for the reply and the FAQ. I > > asked the author to join the list, but I don't think that happened yet? > > > > > > I have a pair made of brass top and bottom > > plates seperated by what looks like an iron > > section. Ther are about 3 1/2" in diameter > > and 1 3/16" thick ( each section being 3/8"). > > > > They are marked "GEOPHONE Joseph G Pollard > > Co. New Hyde Park, N.Y. 1863". > > > > My questions are : > > > > 1. Could they really be that old? > > > > 2. If they are, what were their uses during > > that period ? > > > > > > I've seen the antique Chinese "instrument" with the balls that fall out > > of the dragon mouths, but how far back does something like this go? I > > know that there have been some large earthquakes "recorded" throughout > > history, but I thought that most of the really old ones are estimated by > > damages and people's guesses. > > > > The list has been a little quiet lately hasn't it? > > > > As always, thanks for responses, > > 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) > > To leave this list email listserver@.............. with the body of the > message: leave PSN-L _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Old equipment From: Steve Hammond shammon1@............. Date: Thu, 29 Jul 1999 02:30:11 -0700 David, that a find. Is there any signs of mercury inside it as described in the text? The pipe is definitly a rubber tube connector. Regards, Steve Hammond PSN San Jose, California David & Betti Chase wrote: > > Hello, > > I originally posted the query about the geo > phones. > > If you have an interest , there is a oicture > at the following address: > > http://www.mint.net/~chase/geophone.jpg > > David Chase snip snip > I found the discription of the Geophone > > even more interesting. It reminded me of a pre WWI deveive I read about. > > Here is the text description. > > > > Source: A.S. EVE and D.A. Keys, 1938, Applied Geophysics, Cambridge at > > the University Press Page 230 > > > > Seismic Methods "Thus geophones were used in the War, and may be used > > in mines for detecting the direction of such disturbances as blasting or > > the noise of a pick in tunnelling. Two geophones are employed of similar > > size and construction, in each of which an iron cylinder floats on > > mercury, while above the iron is a layer of enclosed air connected > > through a small hole with a rubber tube leading to the observer's ear. > > One geophone is thus connected to the right ear, the other to the left. > > The shock comming through the ground displaces the case of the geophone, > > while the inertia of the mercury and iron tends to hold them relatively > > at rest. Hence, the air is driven in rhythmic puffs through the holes > > and tubes to the observer's ears, and he hears the sound in a quite > > natural fashion. The remarkable physiological phenomenon of "binaural > > hearing" now comes into play." > > > > What has got my attention is that you did not describe any electrical > > connections and you mentioned an iron section. Is there a coil in the > > Pollard Geophone? Or could it be a orignial pre WWI geophone? > > snip snip _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Old equipment From: Greg ghost@............. Date: Wed, 28 Jul 1999 21:09:31 -0700 David & Betti Chase wrote: > I originally posted the query about the geo > phones. Neat! I guess the mystery is solved, right? Anyone got anything older that 1863? ;) Nice pictures by the way, David. ,Greg _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Old equipment From: Steve Hammond shammon1@............. Date: Thu, 29 Jul 1999 07:29:08 -0700 I have a smoked drum > > Anyone got anything older that 1863? ;) > > Nice pictures by the way, David. > > ,Greg _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Old equipment From: David & Betti Chase chase@........ Date: Thu, 29 Jul 1999 09:50:57 -0400 I haven't taken them apart, although given their weight to size ratio, I wouldn't be surprised that there is mercury inside. Steve Hammond wrote: > > David, that a find. Is there any signs of mercury inside it as described > in the text? The pipe is definitly a rubber tube connector. > > Regards, Steve Hammond > PSN San Jose, California > > David & Betti Chase wrote: > > > > Hello, > > > > I originally posted the query about the geo > > phones. > > > > If you have an interest , there is a oicture > > at the following address: > > > > http://www.mint.net/~chase/geophone.jpg > > > > David Chase > snip snip > > I found the discription of the Geophone > > > even more interesting. It reminded me of a pre WWI deveive I read about. > > > Here is the text description. > > > > > > Source: A.S. EVE and D.A. Keys, 1938, Applied Geophysics, Cambridge at > > > the University Press Page 230 > > > > > > Seismic Methods "Thus geophones were used in the War, and may be used > > > in mines for detecting the direction of such disturbances as blasting or > > > the noise of a pick in tunnelling. Two geophones are employed of similar > > > size and construction, in each of which an iron cylinder floats on > > > mercury, while above the iron is a layer of enclosed air connected > > > through a small hole with a rubber tube leading to the observer's ear. > > > One geophone is thus connected to the right ear, the other to the left. > > > The shock comming through the ground displaces the case of the geophone, > > > while the inertia of the mercury and iron tends to hold them relatively > > > at rest. Hence, the air is driven in rhythmic puffs through the holes > > > and tubes to the observer's ears, and he hears the sound in a quite > > > natural fashion. The remarkable physiological phenomenon of "binaural > > > hearing" now comes into play." > > > > > > What has got my attention is that you did not describe any electrical > > > connections and you mentioned an iron section. Is there a coil in the > > > Pollard Geophone? Or could it be a orignial pre WWI geophone? > > > > snip snip > > _____________________________________________________________________ > > 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) Subject: geophone questions From: angel rodriguez angel@............ Date: Fri, 30 Jul 1999 06:23:24 -0500 Hi all, I am designing and building an array and each of the five stations I'm planning to make like this. geophone to force feedback circuit to hardware log compressor to preamp to VCO to transmitter to receiver to demodulator to sof tware log decompressor to AtoD. This is my questions: Is there any reason not to use a geophone with force feedback? Any other comment about this project are welcome. thanks Angel _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Large Quake Coming In From: Roger Griggs rdg8@......... Date: Sun, 01 Aug 1999 09:12:04 -0700 Recving large pulses coming in... Looks like somewhere in Calif.... _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Large event Now From: Stephen & Kathy mortskm@....... Date: Sun, 01 Aug 1999 09:17:40 -0700 To all, Picking up a large event Now,, Started at 16:07:21 UTC!!! Stephen PSN Station #55 near Pilot Hill Ca 38.828N 120.9784W _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Local area shock??? From: meredith lamb psnseismograph52@.......... Date: Sun, 01 Aug 1999 10:04:41 -0600 Picking up fairly strong signal now. Anybody else? Just put SDR back on line. Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Red Puma says..... From: meredith lamb psnseismograph52@.......... Date: Sun, 01 Aug 1999 10:13:13 -0600 16:06:22.1 37.4n 117.1w mb=5.8 Calif/Nevada border Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Busy day! From: barry lotz gbl@....... Date: Sun, 01 Aug 1999 09:35:47 -0700 I'm also picking up two distant and one local event, Two one after the other. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Red Puma says..... From: barry lotz gbl@....... Date: Sun, 01 Aug 1999 09:42:58 -0700 Meredith Menlo Park shows 16:27:38 36.21w 117.76w 4.0 Coso Junction Barry meredith lamb wrote: > 16:06:22.1 37.4n 117.1w mb=5.8 Calif/Nevada border > > Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Red Puma says..... From: Karl Cunningham karlc@....... Date: Sun, 01 Aug 1999 09:47:35 -0700 http://www.scecdc.scec.org/recenteqs/Quakes/quakes0.html sez... 4.0 99/08/01 09:27:38 36.21N 117.76W 5.8 15 mi NE of COSO JUNCTION 3.9 99/08/01 09:27:04 36.42N 117.20W 6.0 13 mi SSW of STOVEPIPE WELLS times are PDT Karl Cunningham La Mesa, CA. PSN Station #40 karlc@....... _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Red Puma says..... From: barry lotz gbl@....... Date: Sun, 01 Aug 1999 09:52:39 -0700 Karl Some how NEIS shows 5.6 @ 16:06:22 also???? I have not uploaded the two most recent events from the other computer as yet to check what's happening. Afraid of more coming in :) Barry Karl Cunningham wrote: > http://www.scecdc.scec.org/recenteqs/Quakes/quakes0.html sez... > > 4.0 99/08/01 09:27:38 36.21N 117.76W 5.8 15 mi NE of COSO JUNCTION > 3.9 99/08/01 09:27:04 36.42N 117.20W 6.0 13 mi SSW of STOVEPIPE WELLS > > times are PDT > > 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 _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Red Puma says..... From: Karl Cunningham karlc@....... Date: Sun, 01 Aug 1999 10:08:43 -0700 My data agrees with NEIS. And the Coso jucntion event dropped off the Ca-Nv list. -- Karl At 09:52 AM 8/1/99 -0700, you wrote: >Karl > Some how NEIS shows 5.6 @ 16:06:22 also???? I have not uploaded the two >most recent events from the other computer as yet to check what's happening. >Afraid of more coming in :) >Barry _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Red Puma says..... From: barry lotz gbl@....... Date: Sun, 01 Aug 1999 10:53:14 -0700 Karl Not to belabor the issue---- but I finally uploaded the two events. The event @ 16:06:22 appears to be much higher than 5.6. The second event I put at 16:27:25 UTC and it has a magnitude( to me) of around 5.2 based on previous event magnitudes from earlier events at similar distances(Mammoth Lakes). I guess I'll wait til the dust settles. Barry Karl Cunningham wrote: > My data agrees with NEIS. And the Coso jucntion event dropped off the > Ca-Nv list. > > -- Karl > > At 09:52 AM 8/1/99 -0700, you wrote: > >Karl > > Some how NEIS shows 5.6 @ 16:06:22 also???? I have not uploaded the two > >most recent events from the other computer as yet to check what's happening. > >Afraid of more coming in :) > >Barry > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Red Puma says..... From: Karl Cunningham karlc@....... Date: Sun, 01 Aug 1999 11:04:56 -0700 Barry -- I agree with your times and magnitudes for the two events. I'm sure it'll get sorted out on the lists later in the day. Karl At 10:53 AM 8/1/99 -0700, you wrote: >Karl > Not to belabor the issue---- but I finally uploaded the two events. The event @ >16:06:22 appears to be much higher than 5.6. The second event I put at 16:27:25 >UTC and it has a magnitude( to me) of around 5.2 based on previous event >magnitudes from earlier events at similar distances(Mammoth Lakes). I guess I'll >wait til the dust settles. >Barry _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: psn-l@.................. From: Seisguy@....... Date: Sun, 1 Aug 1999 14:36:25 EDT psn-l@.............. ..c The Associated Press LAS VEGAS (AP) - Two strong earthquakes jolted the remote Nevada desert on Sunday, shaking Las Vegas casinos miles away and prompting telephone calls from worried tourists and residents. No damage was reported. A magnitude-6.2 quake near the California-Nevada border struck at 9:06 a.m., followed 21 minutes later by a magnitude-5.2 shaker, said Pat Jorgenson of the U.S. Geological Survey. ``That's two pretty strong shakers. Maybe a few things would have fallen off shelves,'' Jorgenson said. The quakes were centered in Nevada east of Death Valley National Park near Scotty's Castle, about 200 miles northeast of Los Angeles and 50 miles northwest of Las Vegas, Jorgenson said. It wasn't known on which fault the quakes were centered, she said. Several Las Vegas high-rise hotels reported calls from guests wondering what was happening. A security guard at the Stratosphere Hotel and Tower, who asked that his name not be used, said that several people called, including an employee at the top of the 1,149-foot tower who reported ``a little vibration.'' Employees at the Las Vegas Hilton and the Mirage also reported guests calling to ask about the movement, but said the resort sustained no damage and no injuries to any guests or employees. Clark County Aviation Director Randy Walker said employees in the control tower at McCarran International Airport felt movement at the time of the quake but nothing was shut down. ``It wasn't something people got overly concerned about,'' Walker said. A Las Vegas Metropolitan police dispatcher who requested anonymity said dispatchers had received ``quite a few calls'' but no reports of damage or injuries. ``The callers were just trying to figure out what had happened,'' the dispatcher said. ``They reported things shaking and plants swinging.'' AP-NY-08-01-99 1335EDT _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: VBB geophone questions From: S-T Morrissey sean@........... Date: Tue, 3 Aug 1999 13:39:16 -0500 (CDT) Angel, Regarding your question about adding a displacement detector and feedback to a geophone to make a broadband sensor: Back in May I went into some detail in discussing this, so I have re-compiled the material and edited it to the point in question. __________________________________ I have been experimenting for several years with making almost any seismometer into a VBB sensor if the physical parameters are suitable, like the coil resistance. THe largest is a WWNSS LP (15 second T0 and 11 kg mass) vertical that I am running at 600 seconds. I have been experimenting for about two years with making the 4.5 hz HS-1 (by Geospace, but similar to the GSC-11d and the Mark Products L-15B) into a broadband instrument. I use the VRDT displacement sensor mounted externally above the case, with the sensing vane attached to the upper mass ring. With VBB parameters set for 20 seconds and the proper coil resistance, the VBB output is 750 volts/meter/second and the calibrations fit the transfer functions. But the data is to noisy for a sensitive broadband sensor, and I am usually barely able to see an elevated 6-second microseism background of 1 to 2 microns/second. Of course these were very clear (~10x) when hurricane Bonnie passed last August. I also made a nice record (from St. Louis) of the Ohio quake in September, with peak velocities of Lg of about 10 microns/second at about 8 seconds. The trouble with the 4.5hz phone is that the mass is only 23 grams, and the intrinsic damping of 0.28 means that the Q is not very high. From the Riedesel paper this would be expected to have a Brownian noise power spectral density (PSD) level of about -165db (figure 12). (For reference, the USGS low noise model has the 6-second microseism peak at about -140db, the 12-second peak at -160db, and the quiet earth minimum between 40 and 200 seconds is about -185 db.) But the Brownian noise is only one of many noise sources; the circular suspension leaf springs and the fine-wire signal output leads are significant contributors. The Reidesel paper finds that when using the velocity signal coil and a properly selected amplifier, the noise level is -130db at 1 hz, and the 6-second microseisms cannot be seen. We could do much better with a VBB fedback configuration. Initial tests with a fedback geophone were encouraging in this direction. The PSD of several noise samples was about -145db at 6 seconds, but levels off at about -155db at 10 seconds. It has trouble recording teleseisms compared with a larger VBB seis, like a Mb5.O west of Mexico or a 6.2 in China, where the 20-second surface waves were only about 2X the noise. It did make a reasonable record of a Ms 6.0 in the Queen Charlotte Islands (51N,130W). Other problems are with the thermal sensitivity of the mass position and suspension resonances within the high-frequency portion of the VBB passband. THe manufacturers are mum on these; the most notorious are the resonances of the 1-hz L4-C at 16 and 22 hz. The mass position change with temperature is a "don't care" for a velocity sensor, but it causes problems with a displacement output of 250 millivolts/micron, even with reasonable VBB loop gains. The Brownian noise is only one of many noise sources; the circular suspension leaf springs and the fine-wire signal output leads are significant contributors that can raise the noise level by as much as 100 to 1000 times the theoretical calculation of the Brownian noise. We have to properly understand the value that is obtained (in both Riedesel and Melton: references below for the curious reader) for the PSD (Power Spectral Density) of the Brownian noise. The equation simply describes the ideal thermal noise imparted to an isolated mass levitated in a standard atmosphere by a suspension that controls the period and where motion is limited by a dissipative damping system. Note that it says nothing about the noise caused by the physical components of the geophone. The mass of a seismometer is always in motion, even under the quietest conditions. This causes the suspension members to flex, and when non-linearities of the suspension forces are of the order of the forces of earth accelerations applied to the mass, noise results. For example, if the microseism background causes an acceleration of one nano-g (10^-9), which is applied to a mass of 0.023kg, (in the 4.5 hz geophone), F=M*A, and a force of 2.3 x 10^-11 Newtons is applied to the suspension. This is very small compared with the force supporting the mass (F=0.023kg*g= 0.225N), but the suspension still has to flex in a linear fashion to produce an undistorted velocity output. But simple suspensions, such as the etched leaf springs of a geophone, are never intended to be linear at these force levels, so micro-bending and warping, along with hysteresis and edge contact effects, result in fairly broadband noise. Obvously, a larger mass will overcome these effects proportionately. This is why very compact but very high quality flexures are used for low noise sensors. A straight flat flexure clearly has a simple and well defined bending pattern compared to the etched spiral leaf spring of a geophone. Its support or contact points are very well constrained, compared to the circularly clamping rings of a geophone. A linear hinge results in linear mass motion, compared to the small rotation caused by the circular leaf spring. THe epitome of compact self-contained rotational flexures are the pricy "Bendix" devices. The other noise source is the fine wire leads for the signal, calibration, and displacement data. In a common geophone, these are fine coils or "pig-tails" run from the moving coil to terminals on the case. In some geophones, the mass, which is usually a brass ring that the coils are wound on, is split by an epoxy ring, and the leaf-spring suspensions at each end carry the signal to insulated shims that anchor the case ends of the springs. I have found that if the coils are long enough so that they touch themselves, the broadband noise is over 20x of when the coils are stretched so that even successive loops don't touch. And having a calibration coil doubles the number of "pig-tails" making noise, but I need one to verify the response, which I have done with the 4.5hz-VBB. My latest efforts to try to try to reduce the mechanical self noise were only marginally successful . In the data from the Mw 7.1 Monday May 10 in New Britain, P.N.G., the 4-second p-wave was about 4x the noise level at about 20 microns/second, but the 20-second surface waves were less than 2x the noise. A plot of the the PSD of the noise of the sensor shows a relatively flat level of about -130db to -140db from 3 to about 20 seconds where the flat response rolls off; I don't have any higher frequency data. Of course, this is all the mid-day noise of the sensor in the basement 10m from the street, including thermal and barometric noise. Other problems remain: the thermal sensitivity of the mass position (about 4 microns/degree C, dropping with increasing temperature). The mass position change with temperature is a "don't care" for a velocity sensor, but it causes problems with a displacement output of 250 millivolts/micron, even with reasonable VBB loop gains. I use a precision potentiometer to re-balance the sensing bridge over a range of 30 microns (about 600 microns with the feedback on), but this pot adds noise. ____________________________________________________________ A digression for those unfamiliar with the expression: Brownian noise: PSD = (8*pi*k*T)/(M*P*Q) where T is the temperature in Kelvins, M is the mass in kg, P is the period in seconds, and Q is the inverse of the damping (lambda) For example, for the L-4C, M = 1 kg, P = 1 second, and Q is set to 1 ,; T = 300 (room temperature) and k = 1.38*10^-23. Cranking out the numbers gives a PSD for the L4-C of 10^-19. If we substitute the values for the 4.5hz phone, M = 0.023 and P = 0.222, the ratio is 198, so the noise is about 2*10*-17 Some assorted references regarding seismometers and noise: "Limits of Sensitivity of Inertial Seismometers with Velocity Transducers and Electronic Amplifiers"; by Mark A Riedesel, R.D.Moore, and J.A.Orcutt; Bulletin of the Seismological Society of America, Vol. 80, No. 6, December 1990. "The Sensitivity and Dynamic Range of Inertial Seismographs"; by Ben S. Melton; Reviews of Geophysics and Space Physics, Vol 14, No. 1; February 1976; C. American Geophysical Union. "The Design of Miniature Wideband Seismometers" by M.J.Usher, C. Guralp, and R.F. Bursch; Geophysical Journal of the Royal Astronomical Society, vol 55; 1978. "Observations and Modeling of Seismic Background Noise", by Jon Peterson; USGS open file report 93-322, Albuquerque, NM, 1993. A Direct Method for Calculating Instrument Noise Levels in Side-by-Side Seismometer Evaluations", by L. Gary Holcomb, USGS open-file report 89-214, Albuquerque, NM, 1989 A Numerical Study of Some Potential Sources of Error in Side-by-Side Seismometer Evaluations, by L. Gary Holcomb, USGS open-file report #90-preprint, Albuquerque, NM, 1990. _______________________________________________________________________ The 6.0 and aftershocks in the CA/NV border region on May 20 gave everyone some nice data. THe S-TM here, recording on the drum, shows a very nicely dispersed surface wave with periods starting at about 40 seconds. THe later 7.0 at P.N.G. showed several hours of surface waves. The experimental VBB geophone showed the 20-second surface waves, but only at about 4x the noise of 3,5 microns/second. The concurrent pre-event microseisms from the 90-second S-TM were running about 0.24 microns/second, showing clean sine waves with the noise below the least count of my digitizer of 0.1 millivolt, which at 4200 V/m/sec, is about 24 nanometers/second. I do not think that a VBB instrument is worth considering unless it clearly shows the 6-second microseism background. Regarding the mechanical self noise question of the small geophone. As I mentioned, this is the essentially broadband noise, of interest here in the range from 100 seconds to 100 hz, that is caused by the earths' background noise, mostly the 6-second microseisms, (but also from random motion caused by the Brownian thermal noise), moving the suspension and wiring components of the seismometer and causing non-linear motion of the mechanical suspensions. If we dunked the seis in liquid helium to kill the thermal noise, or evacuated it, and/or made a quartz fiber suspension so the Q would be 1000 (damping = zilch), this noise would still be present. The great art of sensor design has focussed on how to allow the mass to move within the frame without the springs, hinges, and wires producing nonlinear forces that are position dependent. Successful designs are very simple, with minimal surface contacts, relatively small hinges or flexures, etc, all of which make them quite fragile. A geophone, however, is mostly the opposite, with the design focussed on robustness and high intrinsic damping (of .3 to .6) that limits the mass excursions in handling. So thermal noise and mechanical noise are not the same, and while a theoretical number can be placed on the Brownian thermal noise, only experimentation can characterize the mechanical noise caused by micropositioning of the moving elements of a seismometer. And the data so far indicate that a geophone is not a promising candidate for a sensitive broadband sensor. Feedback can be used to broaden the response, but it will be sensitive only to larger local and teleseismic events. Regards, Sean-THomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: log amplifiers ?? From: S-T Morrissey sean@........... Date: Tue, 3 Aug 1999 14:55:35 -0500 (CDT) Angel, Regarding your other questions: 1: The current folder of drawings and schematics weighs about 6 ounces. If you send the proper postage to get it to you, I will provide the envelope. I can also provide 1 meter or so of hinge material (0.005" bronze, 0.75" wide). 2: Many have experimented with logrithmic amplifiers to expand the dynamic range of seismic recording. The problem is how to deal with the negative side of the signal. Many schemes of the "invert and add" idea have been tried to handle the bi-polar analog signal, sometimes even developing two log-scaled outputs. These still have problems with low level signals, like near zero voltage. The only successful compression of seismic data has been gain-ranging, where a comparator senses a large signal and knocks down the gain of the amplifier by 1/10 and keeps it there for a duration much longer than the event. Software can find the gain step and restore the gain. Multiple gain-ranging has also worked. It has not been without problems, like dealing with the transient at the gain step. Often it is done at the ADC converter, where the n-bit mantissa is scaled by augmenting the exponent by the inverse of the programmable gain amplifier. Modern 24-bit EDME digitizers avoid the problem altogether for a price. But this means digital telemetry, with all its complications. So multi-level, multi-channel, (40 db separation) analog FM telemetry is the simplest solution. Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Springs From: Greg ghost@............. Date: Tue, 03 Aug 1999 15:01:54 -0700 A while back there was a discussion about spring material for home built instruments. I can't remember if anyone ever found something decent for a reasonable price. Sean-Thomas' email about the geophone broad band mass made me wonder why not just make your own? Does $1000 seem like a reasonable price for a 1 Hz geophone, when you can get a 4.5 Hz for $60? Maybe we could bypass some of that cost? I know the spring in a geophone is pretty fancy for home builders, but maybe something simpler would work almost as good? I know, I'm always asking questions. If I was smart enough and rich enough, I'd get a doctorate in physics, engineering and geology. TIA, Greg _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: log amplifiers ?? From: The Lahrs JohnJan@........ Date: Tue, 03 Aug 1999 18:23:17 -0600 At 02:55 PM 8/3/99 -0500, Sean-Thomas wrote: 2: Many have experimented with logarithmic amplifiers to expand the dynamic range of seismic recording. The problem is how to deal with the negative side of the signal. Quite a few years ago in Alaska we experimented with inverse hyperbolic tangent amplifiers. The function is linear through zero and then becomes logarithmic for larger positive and negative values. I think Analog Devices may have made these amplifiers. We decided to use discrete gain steps instead because to the eye the signals just appeared to be truncated. This was in the pre-digital days of Develocorder film recording. John John C. Lahr POB 1529 Golden, CO 80402 (303) 215-9913 http://lahr.org/john-jan I am only one, But still I am one. I cannot do everything, and because I cannot do everything, I will not refuse to do the something that I can do. Edward Everette Hale _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Springs From: Karl Cunningham karlc@....... Date: Tue, 03 Aug 1999 18:40:16 -0700 Greg -- I would love to find some leaf spring material that is non-magnetic and has near zero temperature coefficients of both linear expansion and modulus of elasticity (the latter two may sort-of go together, metalurgically). I'm sure such alloys exist for the escapement springs of watches and clocks, not to mention commercially-made seismometers. I haven't checked, but I imagine the cost would be high for enough material to build a seismometer similar to Sean-Thomas'. Karl Cunningham La Mesa, CA. PSN Station #40 karlc@....... At 03:01 PM 8/3/99 -0700, you wrote: >A while back there was a discussion about spring material for home built >instruments. I can't remember if anyone ever found something decent for >a reasonable price. Sean-Thomas' email about the geophone broad band >mass made me wonder why not just make your own? Does $1000 seem like a >reasonable price for a 1 Hz geophone, when you can get a 4.5 Hz for $60? >Maybe we could bypass some of that cost? I know the spring in a geophone >is pretty fancy for home builders, but maybe something simpler would >work almost as good? _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Springs From: barry lotz gbl@....... Date: Tue, 03 Aug 1999 22:01:34 -0700 Karl My problem with the leaf springs has been temporary creep(6 months+). I was thinking of experimenting with phosphor bronze as a spring material. I solved the temperature problem by including a bimetal temp gauge coil. It took a little iteration to find the location on the beam that compensated for the temperature flucuations without over compensating. Barry Karl Cunningham wrote: > Greg -- > > I would love to find some leaf spring material that is non-magnetic and has > near zero temperature coefficients of both linear expansion and modulus of > elasticity (the latter two may sort-of go together, metalurgically). I'm > sure such alloys exist for the escapement springs of watches and clocks, > not to mention commercially-made seismometers. I haven't checked, but I > imagine the cost would be high for enough material to build a seismometer > similar to Sean-Thomas'. > > Karl Cunningham > La Mesa, CA. > PSN Station #40 > karlc@....... > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: log amplifiers ?? From: angel rodriguez angel@............ Date: Wed, 4 Aug 1999 05:39:34 -0500 Hello S-t, Tuesday, August 03, 1999, 2:55:35 PM, you wrote: STM> Angel, STM> Regarding your other questions: STM> 1: The current folder of drawings and schematics weighs about 6 ounces. STM> If you send the proper postage to get it to you, I will provide the STM> envelope. I can also provide 1 meter or so of hinge material (0.005" STM> bronze, 0.75" wide). Sean-Thomas, I am having a friend send you $5.00 in an evnvelope to cover the cost of the postage for the drawings and schematics. I will also take you up on the meter of hinge material. My address in Seattle is: Angel Rodriguez 7318 Linden Ave No. Seattle, WA. 98103 I am building these new devices with a friend named Larry. I sent him the compilation of emails that are on the PSN page and he was very impressed. That along with your last two email have save him and me a great deal of work. I can't tell you how much I appreciated it. Warmly, Angel _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: ARCSINH From: John Lahr lahr@................... Date: Wed, 4 Aug 1999 10:11:30 -0600 (MDT) I just looked back at some notes and found that the amplifier was inverse hyperbolic sin (not tangent). Analog Devices made 755N and 755P log and antilog amplifiers that used ARCSINH compression and decompression. This compression function is described in a BSSA paper by Francis Wu and Ernest Jarrold (BSSA, V 64, No. 5, pp 1591-1594. JCLahr _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: sinh^-1 compression From: S-T Morrissey sean@........... Date: Wed, 4 Aug 1999 14:20:52 -0500 (CDT) More info on the bipolar sinh^-1 compression that John Lahr describes can be found in: "Nonlinear Circuits Handbook", edited by D.H.Sheingold of the Analog Devices engineering staff, 1976; ISBN:0-916550-01-X. The sinh^-1 circuit using matched positive and negative input log amplifiers is shown in figure 10. There is also an excellent error vs signal-to-noise analysis table. In general, the conformance errors result in a SN ratio significantly greater than a simple linear ratio for small signals (+,-0.1volt), but it is rather poor for large amplitudes (10V). This is clearly listed as an "ideal" response for matched 752N and 752P log converters, which are necessary for dealing with temperature errors.. (These seem to have been replaced with the AD640 and AD641 devices, at $65 ea.) Later chapters describe the circuits, limitations, and transfer functions of the devices, which (then) cost $49. THey were too DC power hungry, at +,- 15V at +,- 7ma (for one converter) , to be considered for remote battery operated seismic stations. And, as John mentioned, there was the problem of interpreting the non-linear data response in the analog recording (microfilm). The possibility of an inverse function in software to restore the linear response after the FM telemetry and the A to D conversion is an interesting consideration. But whether it is a better solution than a 24-bit ADC and digital telemetry is unknown. Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: STM-8 SEISMOGRAPH BASE From: RADIOTEL@....... Date: Sat, 7 Aug 1999 02:52:23 EDT SEAN-THOMAS, et. al I have just finished completing a seismograph base unit modeled after the design of Sean-Thomas (STM-8). _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: STM-8 SEISMOGRAPH BASE From: RADIOTEL@....... Date: Sat, 7 Aug 1999 03:03:02 EDT SEAN-THOMAS, et.al I have just completed the base unit of the STM-8 seismograph modeled after the design of Sean-Thomas. It presently is configured with a coil and magnet and apears extremely sensitive. Since I have no electronics skills, I was contemplating the next step configuring it with a Shackleford-Gundersen mechanism and the ready made S.G. electronics board made by Larry Cochrane. Do you think this would work and if so any advice would be appreciated. Ultimately I will probably tackle converting it to a VBB. Perhaps Larry will begin selling the VBB electronics. Jim Allen Cerritos, CA. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: NEW SERVER FOR IESN From: "Francesco" franuc@...... Date: Tue, 10 Aug 1999 12:35:04 +0200 Hi all, from today, the I.E.S.N. WEB SITE has moved to a different server. The new address: http://web.tiscalinet.it/iesn (both for english and italian version) Many pages are constructed with java appletts. Regards Francesco
Hi all,
from today,  the I.E.S.N. WEB SITE has moved to a different=20 server.
The new address:
 
http://web.tiscalinet.it/iesn<= /DIV>
(both for english and italian version)
 
Many pages are constructed with java appletts.
 
Regards
Francesco
Subject: Re: NEW SERVER FOR IESN From: The Lahrs JohnJan@........ Date: Tue, 10 Aug 1999 07:46:08 -0600 Hi Francesco, I tried your new page, but got this error message: Symantec Java! ByteCode Compiler Version 210.065 Copyright (C) 1996-97 Symantec Corporation # Applet exception: class mmfaritemmenu could not be loaded # Applet exception: class mmfaritemmenu could not be loaded John At 12:35 PM 8/10/99 +0200, you wrote: >>>> Hi all, from today, the I.E.S.N. WEB SITE has moved to a different server. The new address: http://web.tiscalinet.it/iesn (both for english and italian version) Many pages are constructed with java appletts. Regards Francesco * John C. and Jan H. Lahr * * JohnJan@........ * * 1925 Foothills Road * * Golden, Colorado 80401-1718 * * (303) 215-9913 * * http://lahr.org/john-jan * * http://giseis.alaska.edu/lahr * _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: GI Joe Seismograph From: Doug Crice dcrice@............ Date: Tue, 10 Aug 1999 08:54:57 -0700 Does anybody know anything about the GI Joe Seismograph. It's obviously a toy, but is a functional seismograph? There's a picture on e-bay at http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&tc=ps&item=144158981 Doug _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: NEW SERVER FOR IESN From: Doug Crice dcrice@............ Date: Tue, 10 Aug 1999 08:59:43 -0700 I got the same error message. I am using Netscape Communicator, and I am guessing you designed the page and tested it with Internet Explorer. Microsoft includes some commands that are not supported by other browsers. > Francesco wrote: > > Hi all, > from today, the I.E.S.N. WEB SITE has moved to a different server. > The new address: > > http://web.tiscalinet.it/iesn > (both for english and italian version) > > Many pages are constructed with java appletts. > > Regards > Francesco -- 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) Subject: Re: NEW SERVER FOR IESN From: jmhannon@.................... Date: Tue, 10 Aug 1999 11:32:21 -0500 I tried it with both netscape and IE and got the error message LOAD: class mmfaritemmenu not found Jim Hannon _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: IESN WEB ERROR... From: "Francesco" franuc@...... Date: Tue, 10 Aug 1999 19:42:37 +0200 Hi all. The drawback has been caused by an error of the java codebase, still = linked to the old server. Now, all the pages work fine. Francesco =FF=FE<=00!=00D=00O=00C=00T=00Y=00P=00E=00 =00H=00T=00M=00L=00 = =00P=00U=00B=00L=00I=00C=00 = =00"=00-=00/=00/=00W=003=00C=00/=00/=00D=00T=00D=00 =00H=00T=00M=00L=00 = =004=00.=000=00 = =00T=00r=00a=00n=00s=00i=00t=00i=00o=00n=00a=00l=00/=00/=00E=00N=00"=00>=00= =0D=00=0A= =00<=00H=00T=00M=00L=00>=00<=00H=00E=00A=00D=00>=00=0D=00=0A= =00<=00M=00E=00T=00A=00 = =00c=00o=00n=00t=00e=00n=00t=00=3D=00"=00t=00e=00x=00t=00/=00h=00t=00m=00= l=00;=00 = =00c=00h=00a=00r=00s=00e=00t=00=3D=00u=00n=00i=00c=00o=00d=00e=00"=00 = =00h=00t=00t=00p=00-=00e=00q=00u=00i=00v=00=3D=00C=00o=00n=00t=00e=00n=00= t=00-=00T=00y=00p=00e=00>=00=0D=00=0A= =00<=00M=00E=00T=00A=00 = =00c=00o=00n=00t=00e=00n=00t=00=3D=00"=00M=00S=00H=00T=00M=00L=00 = =005=00.=000=000=00.=002=000=001=004=00.=002=001=000=00"=00 = =00n=00a=00m=00e=00=3D=00G=00E=00N=00E=00R=00A=00T=00O=00R=00>=00=0D=00=0A= =00<=00S=00T=00Y=00L=00E=00>=00<=00/=00S=00T=00Y=00L=00E=00>=00=0D=00=0A= =00<=00/=00H=00E=00A=00D=00>=00=0D=00=0A= =00<=00B=00O=00D=00Y=00 = =00b=00g=00C=00o=00l=00o=00r=00=3D=00#=00f=00f=00f=00f=00f=00f=00>=00=0D=00=0A= =00<=00D=00I=00V=00>=00<=00F=00O=00N=00T=00 = =00s=00i=00z=00e=00=3D=002=00>=00H=00i=00 = =00a=00l=00l=00.=00<=00/=00F=00O=00N=00T=00>=00<=00/=00D=00I=00V=00>=00=0D= =00=0A= =00<=00D=00I=00V=00>=00<=00F=00O=00N=00T=00 = =00s=00i=00z=00e=00=3D=002=00>=00T=00h=00e=00 = =00d=00r=00a=00w=00b=00a=00c=00k=00 =00h=00a=00s=00 =00b=00e=00e=00n=00 = =00c=00a=00u=00s=00e=00d=00 =00b=00y=00&=00n=00b=00s=00p=00;=00a=00n=00 = =00e=00r=00r=00o=00r=00 =00o=00f=00&=00n=00b=00s=00p=00;=00 = =00t=00h=00e=00 =00=0D=00=0A= =00j=00a=00v=00a=00 =00c=00o=00d=00e=00b=00a=00s=00e=00,=00 = =00s=00t=00i=00l=00l=00 = =00l=00i=00n=00k=00e=00d=00&=00n=00b=00s=00p=00;=00t=00o=00 = =00t=00h=00e=00 =00o=00l=00d=00 = =00s=00e=00r=00v=00e=00r=00.=00<=00/=00F=00O=00N=00T=00>=00<=00/=00D=00I=00= V=00>=00=0D=00=0A= =00<=00D=00I=00V=00>=00<=00F=00O=00N=00T=00 = =00s=00i=00z=00e=00=3D=002=00>=00N=00o=00w=00,=00 =00a=00l=00l=00 = =00t=00h=00e=00 =00p=00a=00g=00e=00s=00 =00w=00o=00r=00k=00 = =00f=00i=00n=00e=00.=00<=00/=00F=00O=00N=00T=00>=00<=00/=00D=00I=00V=00>=00= =0D=00=0A= =00<=00D=00I=00V=00>=00&=00n=00b=00s=00p=00;=00<=00/=00D=00I=00V=00>=00=0D= =00=0A= =00<=00D=00I=00V=00>=00<=00F=00O=00N=00T=00 = =00s=00i=00z=00e=00=3D=002=00>=00F=00r=00a=00n=00c=00e=00s=00c=00o=00<=00= /=00F=00O=00N=00T=00>=00<=00/=00D=00I=00V=00>=00<=00/=00B=00O=00D=00Y=00>= =00<=00/=00H=00T=00M=00L=00>=00=0D=00=0A= =00 Subject: SEISMO CHAT-FORUM ON WEB SITE From: "Francesco" franuc@...... Date: Wed, 11 Aug 1999 02:04:56 +0200 Hi all. In the new version of IESN site, I have inserted a new page, available = from http://web.tiscalinet.it/iesn/english.htm link > "Seismo Forum." = This page contains a chat-forum, java based, at disposition of all the = PSN members. =20 It doesn't intend absolutely to replace the mailng-list, but it could = represent a new way of comunication for whoever wants to exchange = information in real time with one or many people, especially in occasion = of particular events, etc.etc. =20 The access is free in every moment; it is not moderated; no limit to = users.=20 To use it, is enough to insert your own name or nick-name and join. No = password required. =20 For the moment it is a lite and experimental version. =20 If the initiative will be pleasant and will have success, I could think = about inserting a professional version. =20 =20 I hope that you like it. =20 =20 Larry, if you want, you can insert this page directly on the PSN site. = I will give you the technical indications and the java source. Francesco
Hi all.
In the new version of IESN site, I have inserted a new page, = available=20 from http://web.tiscalinet.= it/iesn/english.htm =20 link >  "Seismo Forum." 

This page contains a chat-forum, java based,  at = disposition=20 of all the PSN members. 
It doesn't intend absolutely to = replace the=20 mailng-list, but it could represent a new way of = comunication for=20 whoever wants to exchange information in real time with one or many = people,=20 especially in occasion of particular events, etc.etc. 
The = access is=20 free in every moment; it is not moderated; no limit to users. =
To use=20 it, is enough to insert your own name or nick-name and join. No password = required. 
For the moment it is a  lite and experimental=20 version. 
If the initiative will be pleasant and will have = success, I=20 could think about inserting a professional version. 
  =
I hope=20 that you like it. 
 
Larry, if you want,  you can = insert=20 this page directly on the PSN site. I will give you the technical = indications=20 and the java source.
 
Francesco
Subject: SEISMO CHAT-FORUM ON WEB SITE From: Francesco franuc@...... Date: Wed, 11 Aug 1999 02:37:54 +0200 Hi all. In the new version of IESN site, I have inserted a new page, available from http://web.tiscalinet.it/iesn/english.htm link > "Seismo Forum." This page contains a chat-forum, java based, at disposition of all the PSN members. It doesn't intend absolutely to replace the mailng-list, but it could represent a new way of comunication for whoever wants to exchange information in real time with one or many people, especially in occasion of particular events, etc.etc. The access is free in every moment; it is not moderated; no limit to users. To use it, is enough to insert your own name or nick-name and join. No password required. For the moment it is a lite and experimental version. If the initiative will be pleasant and will have success, I could think about inserting a professional version. I hope that you like it. Larry, if you want, you can insert this page directly on the PSN site. I will give you the technical indications and the java source. Francesco Francesco Nucera Osimo - Italy Lat.43.29N Long.13.29E _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: SEISMO CHAT-FORUM ON WEB SITE From: Francesco franuc@...... Date: Wed, 11 Aug 1999 00:37:54 +0200 Hi all. In the new version of IESN site, I have inserted a new page, available from http://web.tiscalinet.it/iesn/english.htm link > "Seismo Forum." This page contains a chat-forum, java based, at disposition of all the PSN members. It doesn't intend absolutely to replace the mailng-list, but it could represent a new way of comunication for whoever wants to exchange information in real time with one or many people, especially in occasion of particular events, etc.etc. The access is free in every moment; it is not moderated; no limit to users. To use it, is enough to insert your own name or nick-name and join. No password required. For the moment it is a lite and experimental version. If the initiative will be pleasant and will have success, I could think about inserting a professional version. I hope that you like it. Larry, if you want, you can insert this page directly on the PSN site. I will give you the technical indications and the java source. Francesco Francesco Nucera Osimo - Italy Lat.43.29N Long.13.29E _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: ECLIPSE NOW ! From: "Giovanni Rotta" rottag@.......... Date: Wed, 11 Aug 1999 12:09:03 +0200 Beatutiful eclipse now here in Northeastern Italy ! Somebody knows something about the phenomenon named "Focault' pendulum = ?" Giovanni Giovanni Rotta Via F. Pizzigoni, 10 33010 Resia (Udine) I Lat. 46.373 N Long. 13.305 E rottag@..........
Beatutiful eclipse now here in Northeastern = Italy=20 !
Somebody knows something about the phenomenon = named=20 "Focault' pendulum ?"
Giovanni
 
Giovanni Rotta
Via F. Pizzigoni, 10
33010 = Resia=20 (Udine) I
Lat. 46.373 N  Long. 13.305 E
rottag@..........
Subject: Re: ECLIPSE NOW ! From: aheerfor@...... Date: Wed, 11 Aug 1999 12:54:36 +0200 Well, there is eclipe here, too at 56 degrees latitude. It's rather dark. I have set up a Foucault's pendulum, and I am currently taking measurements, so yes, I suppose I know something.. Regards, Anders _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: R: ECLIPSE NOW ! From: "Giovanni Rotta" rottag@.......... Date: Wed, 11 Aug 1999 13:33:35 +0200 Hi ! I would like to know if you have recorded some variation of the trace of your pendulum during the eclipse. Thank you ! Giovanni ----- Original Message ----- From: To: PSN-L Mailing List Sent: Wednesday, August 11, 1999 12:54 PM Subject: Re: ECLIPSE NOW ! > Well, there is eclipe here, too at 56 degrees latitude. It's rather dark. > > I have set up a Foucault's pendulum, and I am currently taking > measurements, so yes, I suppose I know something.. > > Regards, Anders > > > > _____________________________________________________________________ > > 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) Subject: Re: R: ECLIPSE NOW ! From: aheerfor@...... Date: Wed, 11 Aug 1999 13:59:38 +0200 > Hi ! I would like to know if you have recorded some variation of the trace of your pendulum during the eclipse. Thank you ! Giovanni < Hmm, yes I have. Before the eclipse the rotation of the azimut seemed to have a fixed rate. During the eclipse, this rate seemed to be near zero. However, I am not very happy about the accuracy of my measurements. One should really spend months on this experiment and considerable money to perfect the measurements, and not a few hours, as I have done. One should not place too much trust in my measurements. If anything, these experiments gives you a healthy respect for the effect of hinges and suspensions on pendulums, which can be transferred to seismometers. It is very diffucult to make a perfect suspension, and I wont claim that I succeeded in this. Regards, Anders _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Help requested! From: Edward Cranswick cranswick@........ Date: Wed, 11 Aug 1999 14:53:17 -0600 Claud Lowe- There is an international organization of amateur seismologists, Public Seismic Network (PSN), who build and operate their own seismographs and exhange data and communicate with one another via the Internet. The best way to become familiar with the PSN is to check out the website . There are six PSN stations in Texas at present, and you can look at some of those sites on the map of worldwide PSN locations . I have forwarded this email to the PSN listserver (PSN-L), and you also could sign up with PSN-L (see directions at ). If you have any other questions, please contact me. Good luck! -Edward Tony Crone wrote: > Hi Ed, > > I'm just back from being out of the office for a couple of weeks and I just > received this message from the staff in our Albuquerque office. Below is a > message from a private citizen who is interested in seismology and > monitoring activity. I thought that you might be the appropriate person to > resond to Mr. Lowe because of your experience with the PSN. I don't know > of any formal organization, but I thought that you might. Could you please > send an e-mail to Mr. Lowe? > > Thanks, > Tony > \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\ > >X-Sender: jackie@............... > >Date: Wed, 28 Jul 1999 13:53:15 -0500 > >To: acrone@...................... > >From: Jackie Savage > >Subject: Help requested! > > > >Tony-- > > > >We recently received the following message via our website, and are > >wondering if you (or anyone else there) know of any such amateur > >organization: > >-------------------------------------------------------------------- > >From: "johnw" > >To: "usgs.asl" > >Subject: Amateurs > >Date: Sun, 25 Jul 1999 08:14:45 -0500 > > > >Can you please tell me if there is a program for amateur > >monitors and if so, what equipment and/or other items are > >needed to be a part of it. > > > >I monitor NEIC daily and am very interested in Seismology > >though I do not have a college degree. Any information would > >be most helpful. I am in contact with another person near my > >home and it would be helpful to him to have someone to compare > >notes with. > > > >Sincerely, > > > >Claud Lowe > >1322 Rock Island #21 > >Irving, TX 75060 > >(972) 870-1356 > > > > ************************************ > Anthony J. Crone > Geologic Hazards Team > Research Geologist > U.S. Geological Survey > MS 966, Box 25046 > Denver, Colorado 80225-0046 U.S.A. > ------------------------------------ > /\ phone: (303) 273-8591 > /\ /\/^^\/\ FAX: (303) 273-8600 > /^^\/ /^^^/^^\/\ e-mail: crone@................... > / / /^^^/^^^/ \ > ************************************* -- 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) Subject: Re: SEISMO CHAT-FORUM ON WEB SITE From: Arie Verveer ajbv@............ Date: Thu, 12 Aug 1999 08:39:07 +0800 Hi Francesco, Using Netscape 4.6, I received this error message. Applet GUIClient Class GUIClient could not be loaded. Sounds like the same problem as suggested in Doug Crice message from a few days ago. Microsoft / Netscape browser compatibility problem. Sounds like fun. -Arie Francesco wrote: > Hi all. > In the new version of IESN site, I have inserted a new page, available from > http://web.tiscalinet.it/iesn/english.htm link > "Seismo Forum." > > This page contains a chat-forum, java based, at disposition of all the PSN > members. > It doesn't intend absolutely to replace the mailng-list, but it could > represent a new way of comunication for whoever wants to exchange > information in real time with one or many people, especially in occasion of > particular events, etc.etc. > The access is free in every moment; it is not moderated; no limit to users. > To use it, is enough to insert your own name or nick-name and join. No > password required. > For the moment it is a lite and experimental version. > If the initiative will be pleasant and will have success, I could think > about inserting a professional version. > > I hope that you like it. > > Larry, if you want, you can insert this page directly on the PSN site. I > will give you the technical indications and the java source. > > Francesco > Francesco Nucera > Osimo - Italy > > Lat.43.29N Long.13.29E > > _____________________________________________________________________ > > 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) Subject: R: SEISMO CHAT-FORUM ON WEB SITE From: "Francesco" franuc@...... Date: Thu, 12 Aug 1999 03:06:25 +0200 Arie, sorry, but I don't know which is the real problem. I use Explorer 5 and all works fine (now also). The same for other = people that use a slower version (>4.0), however with java extension or = plugin. The GUIClient.Class don't runs on my server, but in the Multicity.com = one.=20 Perhaps, when you connected on the chat page, the server was down... Please, try again, and push the reload button. I'm waiting your response. Bye Francesco =FF=FE<=00!=00D=00O=00C=00T=00Y=00P=00E=00 =00H=00T=00M=00L=00 = =00P=00U=00B=00L=00I=00C=00 = =00"=00-=00/=00/=00W=003=00C=00/=00/=00D=00T=00D=00 =00H=00T=00M=00L=00 = =004=00.=000=00 = =00T=00r=00a=00n=00s=00i=00t=00i=00o=00n=00a=00l=00/=00/=00E=00N=00"=00>=00= =0D=00=0A= =00<=00H=00T=00M=00L=00>=00<=00H=00E=00A=00D=00>=00=0D=00=0A= =00<=00M=00E=00T=00A=00 = =00c=00o=00n=00t=00e=00n=00t=00=3D=00"=00t=00e=00x=00t=00/=00h=00t=00m=00= l=00;=00 = =00c=00h=00a=00r=00s=00e=00t=00=3D=00u=00n=00i=00c=00o=00d=00e=00"=00 = =00h=00t=00t=00p=00-=00e=00q=00u=00i=00v=00=3D=00C=00o=00n=00t=00e=00n=00= t=00-=00T=00y=00p=00e=00>=00=0D=00=0A= =00<=00M=00E=00T=00A=00 = =00c=00o=00n=00t=00e=00n=00t=00=3D=00"=00M=00S=00H=00T=00M=00L=00 = =005=00.=000=000=00.=002=003=001=004=00.=001=000=000=000=00"=00 = =00n=00a=00m=00e=00=3D=00G=00E=00N=00E=00R=00A=00T=00O=00R=00>=00=0D=00=0A= =00<=00S=00T=00Y=00L=00E=00>=00<=00/=00S=00T=00Y=00L=00E=00>=00=0D=00=0A= =00<=00/=00H=00E=00A=00D=00>=00=0D=00=0A= =00<=00B=00O=00D=00Y=00 = =00b=00g=00C=00o=00l=00o=00r=00=3D=00#=00f=00f=00f=00f=00f=00f=00>=00=0D=00=0A= =00<=00D=00I=00V=00>=00<=00F=00O=00N=00T=00 = =00s=00i=00z=00e=00=3D=002=00>=00A=00r=00i=00e=00,=00<=00/=00F=00O=00N=00= T=00>=00<=00/=00D=00I=00V=00>=00=0D=00=0A= =00<=00D=00I=00V=00>=00<=00F=00O=00N=00T=00 = =00s=00i=00z=00e=00=3D=002=00>=00s=00o=00r=00r=00y=00,=00 = =00b=00u=00t=00 =00I=00 =00d=00o=00n=00'=00t=00 =00k=00n=00o=00w=00 = =00w=00h=00i=00c=00h=00 =00i=00s=00 =00t=00h=00e=00 =00r=00e=00a=00l=00 = =00=0D=00=0A= =00p=00r=00o=00b=00l=00e=00m=00.=00<=00/=00F=00O=00N=00T=00>=00<=00/=00D=00= I=00V=00>=00=0D=00=0A= =00<=00D=00I=00V=00>=00<=00F=00O=00N=00T=00 = =00s=00i=00z=00e=00=3D=002=00>=00I=00 =00u=00s=00e=00 = =00E=00x=00p=00l=00o=00r=00e=00r=00 =005=00 =00a=00n=00d=00 = =00a=00l=00l=00 =00w=00o=00r=00k=00s=00 =00f=00i=00n=00e=00 = =00(=00n=00o=00w=00 =00a=00l=00s=00o=00)=00.=00 =00T=00h=00e=00 = =00s=00a=00m=00e=00 =00f=00o=00r=00 =00=0D=00=0A= =00o=00t=00h=00e=00r=00 =00p=00e=00o=00p=00l=00e=00 =00t=00h=00a=00t=00 = =00u=00s=00e=00 =00a=00 =00s=00l=00o=00w=00e=00r=00 = =00v=00e=00r=00s=00i=00o=00n=00 = =00(=00&=00g=00t=00;=004=00.=000=00)=00,=00 = =00h=00o=00w=00e=00v=00e=00r=00 =00w=00i=00t=00h=00 =00j=00a=00v=00a=00 = =00e=00x=00t=00e=00n=00s=00i=00o=00n=00 =00o=00r=00 =00=0D=00=0A= =00p=00l=00u=00g=00i=00n=00.=00<=00/=00F=00O=00N=00T=00>=00<=00/=00D=00I=00= V=00>=00=0D=00=0A= =00<=00D=00I=00V=00>=00<=00F=00O=00N=00T=00 = =00s=00i=00z=00e=00=3D=002=00>=00T=00h=00e=00 = =00G=00U=00I=00C=00l=00i=00e=00n=00t=00.=00C=00l=00a=00s=00s=00 = =00d=00o=00n=00'=00t=00 =00r=00u=00n=00s=00 =00o=00n=00 =00m=00y=00 = =00s=00e=00r=00v=00e=00r=00,=00 =00b=00u=00t=00 =00i=00n=00 = =00t=00h=00e=00 =00=0D=00=0A= =00M=00u=00l=00t=00i=00c=00i=00t=00y=00.=00c=00o=00m=00 = =00o=00n=00e=00.=00 = =00<=00/=00F=00O=00N=00T=00>=00<=00/=00D=00I=00V=00>=00=0D=00=0A= =00<=00D=00I=00V=00>=00<=00F=00O=00N=00T=00 = =00s=00i=00z=00e=00=3D=002=00>=00P=00e=00r=00h=00a=00p=00s=00,=00 = =00w=00h=00e=00n=00 =00y=00o=00u=00 = =00c=00o=00n=00n=00e=00c=00t=00e=00d=00 =00o=00n=00 =00t=00h=00e=00 = =00c=00h=00a=00t=00 =00p=00a=00g=00e=00,=00 =00t=00h=00e=00 = =00s=00e=00r=00v=00e=00r=00 =00w=00a=00s=00 =00=0D=00=0A= =00d=00o=00w=00n=00.=00.=00.=00<=00/=00F=00O=00N=00T=00>=00<=00/=00D=00I=00= V=00>=00=0D=00=0A= =00<=00D=00I=00V=00>=00<=00F=00O=00N=00T=00 = =00s=00i=00z=00e=00=3D=002=00>=00P=00l=00e=00a=00s=00e=00,=00 = =00t=00r=00y=00 =00a=00g=00a=00i=00n=00,=00 =00a=00n=00d=00 = =00p=00u=00s=00h=00 =00t=00h=00e=00 =00r=00e=00l=00o=00a=00d=00 = =00b=00u=00t=00t=00o=00n=00.=00<=00/=00F=00O=00N=00T=00>=00<=00/=00D=00I=00= V=00>=00=0D=00=0A= =00<=00D=00I=00V=00>=00&=00n=00b=00s=00p=00;=00<=00/=00D=00I=00V=00>=00=0D= =00=0A= =00<=00D=00I=00V=00>=00<=00F=00O=00N=00T=00 = =00s=00i=00z=00e=00=3D=002=00>=00I=00'=00m=00 = =00w=00a=00i=00t=00i=00n=00g=00 =00y=00o=00u=00r=00 = =00r=00e=00s=00p=00o=00n=00s=00e=00.=00<=00/=00F=00O=00N=00T=00>=00<=00/=00= D=00I=00V=00>=00=0D=00=0A= =00<=00D=00I=00V=00>=00&=00n=00b=00s=00p=00;=00<=00/=00D=00I=00V=00>=00=0D= =00=0A= =00<=00D=00I=00V=00>=00<=00F=00O=00N=00T=00 = =00s=00i=00z=00e=00=3D=002=00>=00B=00y=00e=00<=00/=00F=00O=00N=00T=00>=00= <=00/=00D=00I=00V=00>=00=0D=00=0A= =00<=00D=00I=00V=00>=00<=00F=00O=00N=00T=00 = =00s=00i=00z=00e=00=3D=002=00>=00F=00r=00a=00n=00c=00e=00s=00c=00o=00<=00= /=00F=00O=00N=00T=00>=00<=00/=00D=00I=00V=00>=00=0D=00=0A= =00<=00D=00I=00V=00>=00&=00n=00b=00s=00p=00;=00<=00/=00D=00I=00V=00>=00=0D= =00=0A= =00<=00D=00I=00V=00>=00&=00n=00b=00s=00p=00;=00<=00/=00D=00I=00V=00>=00<=00= /=00B=00O=00D=00Y=00>=00<=00/=00H=00T=00M=00L=00>=00=0D=00=0A= =00 Subject: Re: R: SEISMO CHAT-FORUM ON WEB SITE From: Greg ghost@............. Date: Wed, 11 Aug 1999 19:42:39 -0700 Francesco wrote: =20 > =FF=FE< How does that y-p-< thing translate to English? It's not the first time I've seen it. That's why I asked. ,Greg _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: From: Francesco franuc@...... Date: Thu, 12 Aug 1999 08:59:19 +0200 Arie, sorry, but I don't know which is the real problem. I use Explorer 5 and all works fine (now also). The same for other people that use a slower version (>4.0), however with java extension or plugin. The GUIClient.Class don't runs on my server, but in the Multicity.com one. Perhaps, when you connected on the chat page, the server was down... Please, try again, and push the reload button. I'm waiting your response. Bye Francesco Francesco Nucera Osimo - Italy Lat.43.29N Long.13.29E _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Geophone group buy? From: Larry Cochrane cochrane@.............. Date: Thu, 12 Aug 1999 00:41:30 -0700 Hi All, I have been working with a new PSN member who would like to set up his own station. He lives here in N. California. Too start with he is only interested in local events. Since he doesn't have the time to build his own senor, I offered to look for a geophone for him. I have contacted R.T. Clark and Mitcham Industries for quotes for a 1 hz or 4.5 hz geophone. R.T Clark is offering the following: Mark products L-4C, 1 hz seismometer $375.00 Connecting cable $75.00 (the connecting cable cost is a little high in my opinion ) and Jim at Mitcham Industries sent me this: ------ I'll take $300.00 for a 1 Hz phone. $55.00 for a single 4.5 Hz. It's hard for me to sell these one at a time. You can have 10 of the 4.5's for $375.00. Or 5 ea. 4.5's and one 1 Hz for $475.00. The 1 Hz is Geospace HS-10-1 single vertical geophone in aluminum case and no spike (smooth bottom) with coil position indicator. It has about a 2 meter lead with alligator clip connectors. It weighs about 9 pounds. The 4.5 Hz is Mark Products L10B single vertical geophone in aluminum case with 2 3/4 inch spike,3 foot lead and Amphib IV connector. They have a shunt resistor soldered across them for approximately 60% damping. ------ Jim at Mitcham Industries has contacted me before about having to sell one unit at a time too our members. Since I don't have the free $$$ to stock sensors, I offered to see if we could get together a group buy. So I have a few questions... 1: Is there much difference between L-4C and the HS-10-1 and would the extra 75.00 be worth the money? 2: Anyone interested in a group buy? 3: Does anyone have a sensor, or a source for a sensor, that Doug (the person I'm working with) could buy? Thanks, -Larry Cochrane Redwood City, PSN _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Seismo chat From: Arie Verveer ajbv@............ Date: Thu, 12 Aug 1999 16:02:52 +0800 Hi Francesco, I tried the reload button but the got same problem. I do get the page hit number at the bottom of the page. I think there is a upgrade to netscape 4.6, (4.6.1?), I will load this tonight and see what happens. Regards. Arie. Francesco wrote: > Arie, > sorry, but I don't know which is the real problem. > I use Explorer 5 and all works fine (now also). The same for other people > that use a slower version (>4.0), however with java extension or plugin. > The GUIClient.Class don't runs on my server, but in the Multicity.com one. > Perhaps, when you connected on the chat page, the server was down... > Please, try again, and push the reload button. > > I'm waiting your response. > > Bye > Francesco > > Francesco Nucera > Osimo - Italy > > Lat.43.29N Long.13.29E > > _____________________________________________________________________ > > 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) Subject: Non-linear amplifiers From: George Harris gjharris@............. Date: Wed, 11 Aug 1999 19:23:25 -0400 Regarding the discussion of the use of non-linear amplifiers for compression of seismic output. I have tried a circuit which uses a feed-back amplifier with multiple diodes and resistors in the feedback path. If germanium diodes are used, the output can be switched smoothly at each .5 volt point to any gain desired. It can be used for both posative and negative signals. In a feedback instrument this cannot be in the feedback to the instrument, otherwise the system stability is affected. It must be in a separate output channel. The circuit is any opamp with the primary feedback resistor having direct connection and chosen to give the sensitivity needed for small signals. In parallel with this is a pair of diodes in parallel back to back which are in series with a smaller resistor. This smaller resistor defines a smaller gain when the diodes conduct in either direction. The diode pairs can be continued with ever smaller resistors to define other switching points and scale factors. The output is a smooth curve in both polarities. The probem is that the diode resistance change is not sharp, so that the output curves must be converted by use of a curve approximation in a calculation or table look-up if precision is desired. Has anyone tried something similar? George Harris _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Geophone group buy? From: Terence Dowling dowling@......... Date: Thu, 12 Aug 1999 13:49:46 -0700 I've been on vacation so I hope it isn't too late to respond. I'd be interested io particpiating in a group purchase. I've been too busy (or lazy) to build my own device. I'm more interested in the 1hz device, but if the group wants 4.5hz I'm still interested. Terry Larry Cochrane wrote: > > Hi All, > > I have been working with a new PSN member who would like to set up his own > station. He lives here in N. California. Too start with he is only > interested in local events. Since he doesn't have the time to build his own > senor, I offered to look for a geophone for him. I have contacted R.T. > Clark and Mitcham Industries for quotes for a 1 hz or 4.5 hz geophone. R.T > Clark is offering the following: > > Mark products L-4C, 1 hz seismometer $375.00 > Connecting cable $75.00 > (the connecting cable cost is a little high in my opinion ) > > and Jim at Mitcham Industries sent me this: > ------ > I'll take $300.00 for a 1 Hz phone. $55.00 for a single 4.5 Hz. > > It's hard for me to sell these one at a time. You can have 10 of the 4.5's > for $375.00. Or 5 ea. 4.5's and one 1 Hz for $475.00. > > The 1 Hz is Geospace HS-10-1 single vertical geophone in aluminum case and > no spike (smooth bottom) with coil position indicator. It has about a 2 > meter lead with alligator clip connectors. It weighs about 9 pounds. > > The 4.5 Hz is Mark Products L10B single vertical geophone in aluminum case > with 2 3/4 inch spike,3 foot lead and Amphib IV connector. They have a > shunt resistor soldered across them for approximately 60% damping. > ------ > > Jim at Mitcham Industries has contacted me before about having to sell one > unit at a time too our members. Since I don't have the free $$$ to stock > sensors, I offered to see if we could get together a group buy. > > So I have a few questions... > > 1: Is there much difference between L-4C and the HS-10-1 and would the > extra 75.00 be worth the money? > > 2: Anyone interested in a group buy? > > 3: Does anyone have a sensor, or a source for a sensor, that Doug (the > person I'm working with) could buy? > > Thanks, > > -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 -- Terence Dowling (408) 536-3856 Adobe Systems Inc. dowling@......... _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Non-linear amplifiers From: Michael Chang pya_cha@.................. Date: Thu, 12 Aug 1999 17:27:13 -0700 I have a circuit which converts it's input to the log of it's bipolar peak. It uses Vbe matched small signal transistors, thermally bonded, as the logging element. If kept within a thermal cocoon, it can exhibit an accuracy of within 1dB over an 80dB range. This was something I built long ago as a noise meter without range switching; the meter face spans an 80dB range which can be switched to give RMS, peak, or average responding. I can prepare a schematic if anyone's interested. Michael At 07:23 PM 8/11/99 -0400, you wrote: >Regarding the discussion of the use of non-linear amplifiers for >compression of seismic output. > >I have tried a circuit which uses a feed-back amplifier with multiple >diodes and resistors in the feedback path. If germanium diodes are >used, the output can be switched smoothly at each .5 volt point to any >gain desired. It can be used for both posative and negative signals. >In a feedback instrument this cannot be in the feedback to the >instrument, otherwise the system stability is affected. It must be in a >separate output channel. > >The circuit is any opamp with the primary feedback resistor having >direct connection and chosen to give the sensitivity needed for small >signals. In parallel with this is a pair of diodes in parallel back to >back which are in series with a smaller resistor. This smaller resistor >defines a smaller gain when the diodes conduct in either direction. The >diode pairs can be continued with ever smaller resistors to define other >switching points and scale factors. The output is a smooth curve in >both polarities. > >The probem is that the diode resistance change is not sharp, so that the >output curves must be converted by use of a curve approximation in a >calculation or table look-up if precision is desired. > >Has anyone tried something similar? > >George Harris > > > >_____________________________________________________________________ > >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) Subject: HS-1 and L4-C From: S-T Morrissey sean@........... Date: Thu, 12 Aug 1999 17:31:22 -0500 (CDT) Regarding the HS-1 compared to the L4-C: The HS-1 is a much larger sensor, about 4" in diameter, whereas the L4-C is 2.75" in diameter and will fit inside 3" SCH40 ABS pipe for installing it in a borehole. Installing the HS-1 in a borehole can be difficult if the steel outer case is not provided. 5" SCH40 ABS pipe is needed. THe HS-1 has a period adjustment feature using an astitizing spring. The L4-C period is not adjustable, and tends to get shorter with age, a point to be considered in buying used ones. (have the period tested). The period can be lengthened slightly be tilting the sensor up to 10 degrees. Neither seis is easy to open up for adjustment, since any abuse of the circular leaf springs will result in an unrecoverable loss of the longer period and a trip back to the factory. Electrically they can be equivalent if the coils are similar. THey both have a 1kg mass and an intrinsic damping (Beta0) of around 0.27.. The cable on the L4-C connects to a 5 or 4-pin (w. or wout. cal coil) Bendix connector in the top of the case. THe $75 cable mignt be the "geosensor" cable with the shovel-and-rodent-resistant thick resilient outer jacket. Belden instrumentation cable or shielded phono cable will do. THe original cable is moulded into the top of the shell so that direct installation under water is possible. Most coil resistances for either seis are in the 1200 to 5500 ohm range. I have been searching for one with a galvanometer impedance, less than 300 ohms, to use as a fedback instrument where the high resistances will not work. Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Expiration From: Larry Cochrane cochrane@.............. Date: Thu, 12 Aug 1999 15:44:34 -0700 Charlie, I have a new beta release, it's available on my system at http://www.seismicnet.com/software.html. This beta extends the time out period to the end of the year. I hope to make a real (non-beta) 2.6 release soon...As usual getting the documentation together is taking a longgggg time.... -Larry Cochrane Redwood City, PSN At 12:55 PM 8/12/99 -0400, you wrote: >Hello Larry, > >I notice I have about 3 days on your latest beta Winquake program >before it expires. Do you have an update available? > >Thanks a lot, > >Charlie Plyler >Elfrad Group > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: PSN - Calibrator Question From: "Rex Klopfenstein, Jr" rklopfen@......... Date: Wed, 11 Aug 1999 20:10:00 -0400 Sean I have been playing with the calibrator circuit that you sent and have a few questions. First, is the "Alarm Clock In" a contact closure? Exactly what does the output look like? Thanks in Advance By the way- I am planning to start machining my version of the VBB. I have wired all my boards and need something to test on. Rex Klopfenstein, Jr Bowling Green, OH _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: HS-1 and L4-C From: Greg ghost@............. Date: Thu, 12 Aug 1999 18:47:22 -0700 S-T Morrissey wrote: Sean-Thomas probably already knows this, but I found a couple little things. I think I'd make a decent editor if only I knew English better. ;) > Regarding the HS-1 compared to the L4-C: I'm sure he/you meant HS-10-1 and not HS-1. The HS-1 is a 4.5 Hz model. There's also a HS-10-2 for 2 Hz. Mark Products has a L-22 2 Hz model. > Electrically they can be equivalent if the coils are similar. THey both > have a 1kg mass and an intrinsic damping (Beta0) of around 0.27.. The mass on the LC-4 is 1 Kg, but the HS-10-1 varies between 33 and 29 oz. Both are a little less than 1 Kg. A lot of the details for the GeoSpace geophones are online at the GeoSpace web site. http://www.geospacecorp.com/ Sorry Sean-Thomas, Greg _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Compression From: barry lotz gbl@....... Date: Thu, 12 Aug 1999 20:20:31 -0700 Speaking of log amps etc, I have successfully used an analog mux with code. The reason I prefered this was one can set the threshold for the gain change(up or down). I then included the gain setting as a nibble in the data file. When I compiled the data I normalized the data to the lowest gain. Worked well. Barry _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: HS-1 and L4-C From: S-T Morrissey sean@........... Date: Fri, 13 Aug 1999 00:55:58 -0500 (CDT) OOPS: I was quite clearly trying to answer Larrys question about the difference between the 1-hz L4-C and the HS-10, and writing email under the influence of a fever from the flu. I currently have 7 HS-10-1s in my lab, and a file cabinet top covered with L4-Cs in various states of repair, most sitting on the bottom stop with sagged suspensions or with more serious problems, like lightning damage.. The factory calibration data on the HS-10-1 indicate masses from about 980 to 1010 grams, which is a variant of the tolerance of the wire size for the 4000 ohm coil. Sorry for any confusion. Regards, Sean-THomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: VBB vert. w. SG sensor From: S-T Morrissey sean@........... Date: Sat, 14 Aug 1999 14:19:59 -0500 (CDT) Jim, Congratulations on building your vertical sensor. With a small resistor (like 10 ohms) across the (speaker) coil to damp it,, it does work nicely as a conventional moving coil sensor. If you have something to record it on or with, it will record larger events. But for a sensitivity to all events of interest, the VBB response is necessary. And the VBB output signal is obtained from the displacement detector when the triple feedback is connected. But the displacement data can come from any type of detector, including a capacitive detector similar to the S-G design. I had previously thought of suggesting the use of the S-G sensor, but hesitated to suggest it because I have no information on the sensitivity and particularly the linearity of the S-G capacitive sensor. There is also a question of the stability of the tuned circuits involved, which can seriously affect the linearity. (synchronous demodulators avoid this problem). THere is also a concern with the physical design and the capacitive change with distance; this could probably be improved by making the outer plates significantly larger than the center plate. The VBB feedback, because if its broad frequency response, does require a fairly linear displacement response. So I don't know if the S-G sensor will work with the triple VBB circuit, but it probably will work as for the horizontal S-G design with Larrys' circuit.. I also think that the VRDT electronics design will work with the capacitive sensor if the frequency is shifted up to 100khz or more (limited by the speed of the demodulator switch). Other options are to get someone to make the VRDT and electronics for you. I have been pursuing several options to make the electronics available. BUT FIRST I have been devoting considerable effort to tidying up all the electronics and making a truly final and detailed version of the schematics of all the electronics. This is why I have held the SASE envelopes until I am 99% confident that what is drawn is what is working. Toward this end I have assembled 3 complete multi-period school seismometers that all perform exactly the same, even when the circuit cards are swapped around. Some simplifications have worked out well, and the total number of amplifiers (op-amps) is only 10, 5 of which are in the displacement detector demodulator. I tried to update the schematics on the web site two weeks ago, but was cut short by a lightning power surge that smoked the 5-Volt, 200-amp power supply of our main spark server, so the schematics are still stuck in the scanner work station. (although they have since been updated again).. I am currently getting information on having the printed-circuit boards laid out and printed in limited quantities. But I am still unsure as to when these circuit cards and/or working (assembled) electronics might be available. Maybe by Christmas?. Regards, Sean-THomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Looking for Sensors From: Doug doug@............. Date: Sat, 14 Aug 1999 12:41:17 -0700 Greetings, I am working on setting up a PSN seismic station here in the santa cruz mountains of northern california. It should be interesting because I am about one mile from the san adreas fault line, just 3 miles from the epicenter of the 89 loma prieta quake. Larry Cochrane is putting together the interface hardware for me, including a 3 channel amp/filter board, the SG electronics board, radio telemetry board, GPS timing and A/D converter. The problem I have is locating sensors. My initial interest is for local event monitoring, so geophones are probably how I will get started. But I am also interested in setting up other sensors like the lehman and SG types. I am wondering if anyone out there knows of any sources for sensors, either geophones, lehman, or shakleford-gunderson style sensors. If you have any of these to sell, or know someone who does, please let me know. I am also wondering if anyone out there would be willing to build me the lehman or SG type sensors, let me know. BTW I have some live weather data from my location posted here: http://sensorium.los-gatos.net/ You can get a weather station from dallas semiconductor for $80 that includes temperature, wind speed, and wind direction. For another $50 you can add a rain guage. They also provide free source code for these devices. See http://www.ibutton.com/weather/index.html. Here are some other interesting weather related sensors: http://www.ibutton.com/ibuttons/thermochron.html http://www.pointsix.com/products/index.htm#1wireprobes http://www.texas-weather.com Thanks, Doug _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: An event From: Nick & Sophie Caporossi nickcap@............. Date: Sat, 14 Aug 1999 17:59:49 -0400 Hi All: Got something this morning but I can't confirm it. It occurred at 8/14/99 at 00:36:11 UTC, 8:36PM EST (my time). Did anyone pick up something at that time? Don't know where to find the Location and Time for events? The Lamont-Doherty Cooperative Seismographic Network at: >http://www.ldeo.columbia.edu/cgi-bin/mth-cgi-bin/24hr_heli Shows the event at about the same time as I do. >"http://civeng.carleton.ca/cgi-bin2/quakes" Does not seem to be updating. Anyone know where I can get an up to date listings? Thanks Nick _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: R: An event From: "Francesco" franuc@...... Date: Sun, 15 Aug 1999 00:20:38 +0200 Hi Nick, this is the event 00.35.11 Ms 6.2 Loc.: Southern Sumatera/Sonda Strait.=20 No exactly location, because the USGS quake-finger today is down... Can you see at = http://www-csem.bruyeres.cea.fr/cgi-bin/ALERT_all_messages.sh?1 of EMSC or USGS Live-cam at http://aslwww.cr.usgs.gov/Seismic_Data/heli2.htm See also my file posted this morning (for me..) on PSN-events. Francesco, I.E.S.N. Italy =FF=FE<=00!=00D=00O=00C=00T=00Y=00P=00E=00 =00H=00T=00M=00L=00 = =00P=00U=00B=00L=00I=00C=00 = =00"=00-=00/=00/=00W=003=00C=00/=00/=00D=00T=00D=00 =00H=00T=00M=00L=00 = =004=00.=000=00 = =00T=00r=00a=00n=00s=00i=00t=00i=00o=00n=00a=00l=00/=00/=00E=00N=00"=00>=00= =0D=00=0A= =00<=00H=00T=00M=00L=00>=00<=00H=00E=00A=00D=00>=00=0D=00=0A= =00<=00M=00E=00T=00A=00 = =00c=00o=00n=00t=00e=00n=00t=00=3D=00"=00t=00e=00x=00t=00/=00h=00t=00m=00= l=00;=00 = =00c=00h=00a=00r=00s=00e=00t=00=3D=00u=00n=00i=00c=00o=00d=00e=00"=00 = =00h=00t=00t=00p=00-=00e=00q=00u=00i=00v=00=3D=00C=00o=00n=00t=00e=00n=00= t=00-=00T=00y=00p=00e=00>=00=0D=00=0A= =00<=00M=00E=00T=00A=00 = =00c=00o=00n=00t=00e=00n=00t=00=3D=00"=00M=00S=00H=00T=00M=00L=00 = =005=00.=000=000=00.=002=003=001=004=00.=001=000=000=000=00"=00 = =00n=00a=00m=00e=00=3D=00G=00E=00N=00E=00R=00A=00T=00O=00R=00>=00=0D=00=0A= =00<=00S=00T=00Y=00L=00E=00>=00<=00/=00S=00T=00Y=00L=00E=00>=00=0D=00=0A= =00<=00/=00H=00E=00A=00D=00>=00=0D=00=0A= 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w=00w=00.=00c=00r=00.=00u=00s=00g=00s=00.=00g=00o=00v=00/=00S=00e=00i=00s= =00m=00i=00c=00_=00D=00a=00t=00a=00/=00h=00e=00l=00i=002=00.=00h=00t=00m=00= "=00>=00h=00t=00t=00p=00:=00/=00/=00a=00s=00l=00w=00w=00w=00.=00c=00r=00.= =00u=00s=00g=00s=00.=00g=00o=00v=00/=00S=00e=00i=00s=00m=00i=00c=00_=00D=00= a=00t=00a=00/=00h=00e=00l=00i=002=00.=00h=00t=00m=00<=00/=00A=00>=00<=00/= =00F=00O=00N=00T=00>=00<=00/=00D=00I=00V=00>=00=0D=00=0A= =00<=00D=00I=00V=00>=00<=00F=00O=00N=00T=00 = =00s=00i=00z=00e=00=3D=002=00>=00S=00e=00e=00 =00a=00l=00s=00o=00 = =00m=00y=00 =00f=00i=00l=00e=00 =00p=00o=00s=00t=00e=00d=00 = =00t=00h=00i=00s=00 =00m=00o=00r=00n=00i=00n=00g=00 =00(=00f=00o=00r=00 = =00m=00e=00.=00.=00)=00 =00o=00n=00 =00=0D=00=0A= =00P=00S=00N=00-=00e=00v=00e=00n=00t=00s=00.=00<=00/=00F=00O=00N=00T=00>=00= <=00/=00D=00I=00V=00>=00=0D=00=0A= =00<=00D=00I=00V=00>=00&=00n=00b=00s=00p=00;=00<=00/=00D=00I=00V=00>=00=0D= =00=0A= =00<=00D=00I=00V=00>=00<=00F=00O=00N=00T=00 = =00s=00i=00z=00e=00=3D=002=00>=00F=00r=00a=00n=00c=00e=00s=00c=00o=00,=00= &=00n=00b=00s=00p=00;=00 =00I=00.=00E=00.=00S=00.=00N=00.=00 = =00I=00t=00a=00l=00y=00<=00/=00F=00O=00N=00T=00>=00<=00/=00D=00I=00V=00>=00= <=00/=00B=00O=00D=00Y=00>=00<=00/=00H=00T=00M=00L=00>=00=0D=00=0A= =00 Subject: Re: VBB vert. w. SG sensor From: RADIOTEL@....... Date: Sat, 14 Aug 1999 22:04:38 EDT SEAN-THOMAS, et.al Thanks for the advice on using a 10 ohms resister for damping my new STM-8 moving coil sensor. My unit worked as soon as constructed netting me two earthquakes the first day of operation and approximately one to three each day there-after. And almost as rewarding my wife loves the look-she says that it looks so professional! I am going to now do a lot of experimenting with it, possibly purchasing one of Larry's boards next month. In the interim, please know what a great debt we all owe you for sharing your design and allowing us to pester you with so many questions. Jim Allen Cerritos, Calif. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: An event From: RLLaney@....... Date: Sun, 15 Aug 1999 12:43:44 EDT Hi Nick: Yes, I got it here as well at 00:36:24. Francesco, thanks for the info on the location. Bob Laney Herndon, VA _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Geophone group buy & Tinkering in Las Vegas... From: jimo17@........ Date: Sun, 15 Aug 1999 19:14:00 -0700 Larry-and PSN Members (The Can-Do Folks), I am in the process of developing seismic systems (as cheap as possible, so I can get them in as many schools as possible) for Clark County Schools, here in Las Vegas, which has over 200,00 students. I am thinking along the lines of PEPP, but with a much more affordable system. Recording at UNLV: I recently purchased your Amp/Filter (3 Channels) and the A/D board and hooked it up to the UNLV, 20 year old, Lehman (E-W) and 3 S-13's (X,Y,Z). The Lehman went thru your Amp/Filter (set at 2K gain) while the S-13's went thru a Geotech amplifier of 1K gain, and all 4 were recorded on a Gateway PC (8Mb Ram & 400Mb HD) at 50 sps. I was able to record the Scotty Castle sequence (M=5.7, 8/1/99), was I impressed, even the Event Detector worked! Now, all channels went off scale on the Main Shock, it appeared either the Amp or A/D clipped on the Lehman, while it appeared the S-13 seismometer, it self, was saturated, as the recording was very peculiar looking, not the normal clipping. We were 250 Km's away from the epicenter. The Lehman also has a 10hz oscillation which is small on the seismogram and comes out as a spike on the spexa. Question 1. Is it likely the S-13 seismometer itself would get saturated from this Eq ? Question 1a. How do I tell rather the Amp or A/D board clipped? Question 1b. Does the Lehman have another resonant frequency at 10 HZ? Geophone Testing (L-4): I live about 5 Km's from a recent M=2.5, May 6, which I felt. UNR has two sites 30 Km's and 50 Km's away in opposite directions from Boulder City, (BC), (BC is 30km's South-East of Las Vegas), UNR recorded the M=2.5, but they need a third site to get a better location. I hope to be that third site to pin down these small shocks which go unnoticed on their Network, here in BC. I just started testing 3 L4's, 2 H & 1 Z, here at my house in Boulder City, NV . I have them on my patio with 100' of coaxial cable which came with the sensors. I borrowed them from UNLV to determine if they would be good for detecting local EQ's. I put their output directly into a DataQ A/D board, (DI-194, 16 bit, 4 channel, 10V FS, sells for $100) thru the 100' cable, which hooks up externally to my PC( HP 96 Mb Ram & 4 GB HD) thru the Com1 port. I obviously need a preamplifier as I don't even see road traffic, they do slightly pick me up when I walk by. Question 2. What is the L-4 output? Question 3. Can I use your Amp/Filt board as a Pre-amp? and do I need to place it very close to the L4 seismometer to keep a short input cable? Question 4. Should your Filter board setting be something like 0.5 to 30 Hz for the L4. Question 5. I have a program, Atomic Clock, which calls Boulder or Fort Collins, CO to reset my PC clock. I am wondering if that is satisfactory, as my main interest is just S-P values, to locate local Eq's. At the present time I have the Lehman, 3 S-13's and 2 Z L-4's recording at UNLV using your Amp/filter board on the Lehman and L-4's. I believe you set two of the channels to 20 hz for the Geophones and 10 hz for the Lehman. I am ready to order another Amp/Filter board unless someone can suggest a cheaper pre-amp.....for the L-4's. Jim O'Donnell Retired Geophysicist _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: More on the geophone group buy. From: Larry Cochrane cochrane@.............. Date: Sun, 15 Aug 1999 22:50:03 -0700 All, I contacted Jim Croix at Mitcham Industries to see how many of the 1 hz and 4.5 hz sensors he has. He has 40-50 of each type of sensor, so everyone who contacted me can get one. This is what I have so far for the group buy: Who Qt Sensor Type David Okrent 1 4.5 hz Terence Dowling 1 1 hz Arie Verveer 1 1 hz Tom Frey 1 1 hz Doug at los-gatos.net 1 1 hz Larry Cochrane 1 1 hz If you want to be added to the list please let me know ASAP. I will contact Jim in a few days to get a final price for the equipment. Regards, Larry Cochrane Redwood City, PSN _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Geophone group buy & Tinkering in Las Vegas... From: Larry Cochrane cochrane@.............. Date: Mon, 16 Aug 1999 00:35:00 -0700 Jim, Thanks for your message. Answers to some of your questions below.... At 07:14 PM 8/15/99 -0700, you wrote: >Larry-and PSN Members (The Can-Do Folks), > >I am in the process of developing seismic systems (as cheap as possible, >so I can get them in as many schools as possible) for Clark County >Schools, here in Las Vegas, which has over 200,00 students. I am >thinking along the lines of PEPP, but with a much more affordable system. > > >Recording at UNLV: >I recently purchased your Amp/Filter (3 Channels) and the A/D board and >hooked it up to the UNLV, 20 year old, Lehman (E-W) and 3 S-13's (X,Y,Z). >The Lehman went thru your Amp/Filter (set at 2K gain) while the S-13's >went thru a Geotech amplifier of 1K gain, and all 4 were recorded on a >Gateway PC (8Mb Ram & 400Mb HD) at 50 sps. I was able to record the >Scotty Castle sequence (M=5.7, 8/1/99), was I impressed, even the Event >Detector worked! Now, all channels went off scale on the Main Shock, it >appeared either the Amp or A/D clipped on the Lehman, while it appeared >the S-13 seismometer, it self, was saturated, as the recording was very >peculiar looking, not the normal clipping. We were 250 Km's away from >the epicenter. The Lehman also has a 10hz oscillation which is small on >the seismogram and comes out as a spike on the spexa. >Question 1. Is it likely the S-13 seismometer itself would get saturated >from this Eq ? >Question 1a. How do I tell rather the Amp or A/D board clipped? I don't think the sensor saturated. Its probably too much gain through the system. >Question 1b. Does the Lehman have another resonant frequency at 10 HZ? My Lehman has several resonances. Its hard too say where they will show up. > > Geophone Testing (L-4): > I live about 5 Km's from a recent M=2.5, May 6, which I felt. UNR has >two sites 30 Km's and 50 Km's away in opposite directions from Boulder >City, (BC), (BC is 30km's South-East of Las Vegas), UNR recorded the >M=2.5, but they need a third site to get a better location. I hope to be >that third site to pin down these small shocks which go unnoticed on >their Network, here in BC. I just started testing 3 L4's, 2 H & 1 Z, >here at my house in Boulder City, NV . I have them on my patio with 100' >of coaxial cable which came with the sensors. I borrowed them from UNLV >to determine if they would be good for detecting local EQ's. I put their >output directly into a DataQ A/D board, (DI-194, 16 bit, 4 channel, 10V >FS, sells for $100) thru the 100' cable, which hooks up externally to my >PC( HP 96 Mb Ram & 4 GB HD) thru the Com1 port. I obviously need a >preamplifier as I don't even see road traffic, they do slightly pick me >up when I walk by. >Question 2. What is the L-4 output? Sorry, I don't know the sensitivity of this sensor. >Question 3. Can I use your Amp/Filt board as a Pre-amp? and do I need to >place it very close to the L4 seismometer to keep a short input cable? If your A/D card input is from 0 to 10 vdc and not +-10 vdc there will be a problem using my Amp card. It produces a +- output voltage. >Question 4. Should your Filter board setting be something like 0.5 to 30 >Hz for the L4. For geophones I have been using .5 to 20 hz, but I can make it 30 hz if needed. >Question 5. I have a program, Atomic Clock, which calls Boulder or Fort >Collins, CO to reset my PC clock. I am wondering if that is >satisfactory, as my main interest is just S-P values, to locate local >Eq's. Don't know. > >At the present time I have the Lehman, 3 S-13's and 2 Z L-4's recording >at UNLV using your Amp/filter board on the Lehman and L-4's. I believe >you set two of the channels to 20 hz for the Geophones and 10 hz for the >Lehman. Yes, this is correct. > >I am ready to order another Amp/Filter board unless someone can suggest a >cheaper pre-amp.....for the L-4's. > >Jim O'Donnell >Retired Geophysicist -Larry Cochrane Redwood City, PSN _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: More on the geophone group buy. From: jimo17@........ Date: Mon, 16 Aug 1999 06:43:11 -0700 Larry This sounds like a good idea.... Put me down for 2 Geophones, a 1Hz and a 4.5Hz... Thanks, Jim O'Donnell _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: More on the geophone group buy. From: "Rex Klopfenstein, Jr" rklopfen@......... Date: Mon, 16 Aug 1999 11:03:59 -0400 Your can put me down for qty 1 of the 1 Hz model. Larry Cochrane wrote: > All, > > I contacted Jim Croix at Mitcham Industries to see how many of the 1 hz and > 4.5 hz sensors he has. He has 40-50 of each type of sensor, so everyone who > contacted me can get one. > > This is what I have so far for the group buy: > > Who Qt Sensor Type > David Okrent 1 4.5 hz > Terence Dowling 1 1 hz > Arie Verveer 1 1 hz > Tom Frey 1 1 hz > Doug at los-gatos.net 1 1 hz > Larry Cochrane 1 1 hz > > If you want to be added to the list please let me know ASAP. I will contact > Jim in a few days to get a final price for the equipment. > > 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 -- Rex Klopfentein, Jr. rklopfen@......... http://www.wcnet.org/~rklopfen _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Expiration From: Edward Cranswick cranswick@........ Date: Mon, 16 Aug 1999 10:20:08 -0600 Larry- except the version identifies itself as 2.6.2 beta. -Edward Larry Cochrane wrote: > Charlie, > > I have a new beta release, it's available on my system at > http://www.seismicnet.com/software.html. This beta extends the time out > period to the end of the year. I hope to make a real (non-beta) 2.6 release > soon...As usual getting the documentation together is taking a longgggg > time.... > > -Larry Cochrane > Redwood City, PSN > > At 12:55 PM 8/12/99 -0400, you wrote: > >Hello Larry, > > > >I notice I have about 3 days on your latest beta Winquake program > >before it expires. Do you have an update available? > > > >Thanks a lot, > > > >Charlie Plyler > >Elfrad Group > > > > _____________________________________________________________________ > > 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) Subject: Re: More on the geophone group buy. From: Tobin Fricke tobin@....... Date: Mon, 16 Aug 1999 13:27:24 -0700 (PDT) This Geophone group buy sounds like a good opportunity for me to establish a seismometer of my own.. I'm already planning on building a Lehman when I get home (I'm in Alaska for the summer) but a geophone sounds like fun. I live in a suburban neighborhood in Southern California, and I don't really know anything about Geophones per se. What geophone would give me the most earthquake-listening entertainment, and how much do they cost? Thanks, Tobin _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: seismometer sensitivity From: S-T Morrissey sean@........... Date: Mon, 16 Aug 1999 17:32:23 -0500 (CDT) Regarding the questions of the sensitivity of various seismometers, particularly compact 1-hz and shoter period phones: There is no unique answer to the question, since they are all manufactured to meet a wide range of data and recording requirements. THe big variable is the coil resistance, which is kept low (hundreds of ohms) for galvanometric recording or long field strings, but is made high (5500 ohms for a typical L4-C) for amplified applications like telemetry. THe upper limit is where the resistance is so high that the coil cannot be used for damping because it limits the current. Some seises (long period) have a 100,000 ohm coil for the signal and a separate 500 ohm coil for damping. The other variable has been the use of improved magnets; some manufacturers have recently switched to niobium-based alloys, which can provide over 5x the output from the same package. So the best bet is to get the data for EACH phone from the manufacturer. Most provide a label with at least the coil resistance (which you can measure, of course) and the generator constant of either the main coil or the calibration coil. Most have tables or graphs of the output for various coil resistances; these are accurate to about 20%. Some show the output level at various percentages of critical damping (this is not the same as the open-circuit output), and even give the damping resistance (which has to be corrected for the parallel input resistance of the amplifier). Most geophones are sealed so that directly measuring the generator constant by a weight-lift test cannot be done. If the calibrator coil constant is given, this can be used to determine the output of the main coil. THen the actual input to the amplifier with the damping resistor in place can be determined. Years ago, we calibrated 50 or so L4-Cs and found that the nominal output (270v/m/sec for a 5500 ohm coil) varied by 20%, so we used a series/shunt method (per. J. Eaton of the USGS) to standardize all of them to a damping of 0.7 and an input to the amplifier of 100V/m/sec. The subsequent shake-table calibration showed agreement within a few percent. Obviously a shake-table provides an immediate answer to the sensitivity question as well as the response of the amplifier and data system. But they are rare, so weight-lift calibration can provide absolute results IF there is access to the moving mass. Like for the HS-10-1 with the external calibration coil and astitizing spring (to trim the period), the test weights (100 to 500 milligrams) can be applied directly or via 45 degree threads (the explanation is long and detailed) for a horizontal. Then there is the further question of the sensitivity needed to detect a given quake. Obviously, "cranking up the gain" is fun, but not if it just amplifies the freeway 1 km away. But for example: with the L4-Cs damped and trimmed to 100v/m/sec, we found that amplifier gains of 60 to 72 db (x1000 to x4000, depending on the site noise) were adequate to record a Mb=2.0 at 20km in the New Madrid region. In the west (CA and NV), site noise can be much less, but attenuation can be much more (up to 10x), so amplifier gains of 84 db (x16,000) might be needed for the same result. So what does this mean for YOUR geophone/damping/amplifier. If the L4-C above had a net output of 100V/m/sec, and is amplified 1000 times, the recorder is getting a signal of 0.1 volt/micron/sec or 0.1 millivolt/ nanometer/second.. In terms of displacement, a nm/sec is 1/(2*pi)*nanometers at a period of one second. If your amplifier noise floor is 10mv, your displacement noise sensitivity is 16 X 10^-9 meter for a 1-second wave. Assuming that you can see a 1-second waveform at 10 times the noise level, what size earthquake might be detected at this level? Using a standard magnitude scale "Ms = logA/P + 1.66*log(distance) - 0.18", and using a distance of 1 degree (about 100 km), and A is the amplitude in nanometers, (10x the noise is 160 nm), we get a Ms magnitude of 2.02, which is a quake very near the threshold of sensation. If the event is 2 degrees away, it will be a magnitude 2.5. But say that you forget the preamp, but your digitizer noise is only 1mv, so your detection level is 16000 nanometers (16 microns), the quake at 1 degree will be a magnitude 4.02. So even with a high-output sensor like the L4-C, a pre-amp is necessary. 4.5 hz phones will need up to 10x more gain, especially if the amplifier is "countoured" to boost the 1-hz output. Last year I scanned the old pencil drawing of the pre-amp that I use, along with a photo of it to my web site http://www.eas.slu.edu/People/STMorrissey/index.html ...: stmmisc.html" PSN INFO ... SLU Seismic Network I have since re-drawn it with the latest details, but it is not yet posted. I can send the new schematic to any SASE, and if Larry wants to provide it, I can send him the artwork (which is just that; it would probably have to be re-drawn for a numerical control PC board shop). With a few compromises, it should cost around $100. With micropower amplifiers, it has a current drain of about 0.1 milliamp, so it will run for several years from a pair of 6-volt alkaline lantern batteries. A final curiosity regarding the data from an S-13 from a Ms5.7 at 200km (I'm guessing the distance). Using the magnitude formula gives a value for logA/P = 5.38, so if P = 1 second, the p-p ground amplitude is about 240043 nanometers, or about 0.24mm. The peak velocity (at 1 hz) is 1.5mm/sec. The standard S-13 has a 3600 ohm coil with a generator constant of 629 V/M/sec. When damped critically with 6300 ohms, the output is 400V/m/sec. or 0.4 volt/mm/sec. So a peal velocity of 1.5mm/sec. is 0.6 volts, which will saturate any amplifier with gain much more than 10. But the seis has an air gap length, or p-p coil movement, of 1.9 mm before it "hits the stops". Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: new event From: barry lotz gbl@....... Date: Mon, 16 Aug 1999 17:24:08 -0700 Something coming in @ around 00:16 UTC here. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: PSN - Calibration Board Question From: "Rex Klopfenstein, Jr." rklopfen@......... Date: Mon, 16 Aug 1999 20:32:33 -0400 Sean- I have just finished building the calibration board you sent me. It seems to be working OK (I haven't went through the output with a 'fine-tooth comb' yet). I have answered my previous question: the input is a contact closure and the U12 circuit appears to be a single-shot to reset/start counting. I do have several questions on the function of some of the potentiometers. I am using the part# from your drawing. I am assuming that the 100K (R13) potentiometer adjusts the magitude of the "D/A" counting pair? I also assume that the 5K (R23) potentiometer is used to balance the bridge when the seismo coil is inserted. Finally, what is the function of the 100K (R14) potentiometer? Thanks in advance Rex Klopfenstein, Jr. Bowling Green, OH _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: new event From: "Rex Klopfenstein, Jr." rklopfen@......... Date: Mon, 16 Aug 1999 20:39:13 -0400 Where are you located?? barry lotz wrote: > Something coming in @ around 00:16 UTC here. > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@.............. with the body of the > message: leave PSN-L -- Rex Klopfenstein, Jr. Bowling Green, OH rklopfen@......... www.wcnet.org/~rklopfen _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: new event From: barry lotz gbl@....... Date: Mon, 16 Aug 1999 17:45:04 -0700 About 200km east of San Francisco Ca. I looked at the live helicorder and it looked like the largest records were from Russa or Norway. Barry Rex Klopfenstein, Jr. wrote: > Where are you located?? > > barry lotz wrote: > > > Something coming in @ around 00:16 UTC here. > > > > _____________________________________________________________________ > > > > Public Seismic Network Mailing List (PSN-L) > > > > To leave this list email listserver@.............. with the body of the > > message: leave PSN-L > > -- > Rex Klopfenstein, Jr. > Bowling Green, OH > rklopfen@......... > www.wcnet.org/~rklopfen > > _____________________________________________________________________ > > 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) Subject: Re: new event From: barry lotz gbl@....... Date: Mon, 16 Aug 1999 17:53:33 -0700 Rex Looks like Red Puma is putting it in the area of Turkey. If it is is would seem to be pretty large. Barry Rex Klopfenstein, Jr. wrote: > Where are you located?? > > barry lotz wrote: > > > Something coming in @ around 00:16 UTC here. > > > > _____________________________________________________________________ > > > > Public Seismic Network Mailing List (PSN-L) > > > > To leave this list email listserver@.............. with the body of the > > message: leave PSN-L > > -- > Rex Klopfenstein, Jr. > Bowling Green, OH > rklopfen@......... > www.wcnet.org/~rklopfen > > _____________________________________________________________________ > > 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) Subject: Re: new event From: ACole65464@....... Date: Mon, 16 Aug 1999 20:53:03 EDT Hi all, The large surface waves are really starting to roll through here in Edmonds Washington state, 5:53PM PDT. Allan Coleman _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: new event From: Seisguy@....... Date: Mon, 16 Aug 1999 20:58:46 EDT AP reports a very recent quake in Turkey, could this be the new event? Earthquake hits Turkey, residents on the streets ANKARA, Aug 17 (Reuters) - An earthquake shook Turkey in the early hours of Tuesday cutting electricity and sending residents out onto the streets in the capital Ankara and in the country's largest city Istanbul, some 440 km (275 miles) away. ``It shook the house for nearly a minute. We went down to the street straight away,'' said Istanbul resident Veysel Karakaya. There were no immediate reports or casualties or damage. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: new event From: ACole65464@....... Date: Mon, 16 Aug 1999 21:08:48 EDT Its got to big, the remotely located 1 Hz vertical seismometers around this state (Washington) are responding with large 20 second period waves. Allan Coleman _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: new event From: meredith lamb psnseismograph52@.......... Date: Mon, 16 Aug 1999 19:09:59 +0000 SDR still smeared here after about a 1/2 hour. Long period waves. Guess maybe upper 7's or possible ? Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: new event From: Seisguy@....... Date: Mon, 16 Aug 1999 21:21:13 EDT M6.8 sound correct? Mike Strong Earthquake Shakes Turkey ..c The Associated Press ISTANBUL, Turkey (AP) - A strong earthquake with a magnitude of 6.8 struck western Turkey early Tuesday, sending people fleeing into the streets and collapsing some buildings, a private radio said. There were no immediate reports of casualties, private TGRT said. The radio said the epicenter of the quake was the city of Izmit, just east of Istanbul. AP-NY-08-16-99 2107EDT _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Fwd: Strong Earthquake Shakes Turkey From: Seisguy@....... Date: Mon, 16 Aug 1999 21:24:15 EDT Strong Earthquake Shakes Turkey ..c The Associated Press ISTANBUL, Turkey (AP) - A strong earthquake with a magnitude of 6.8 struck western Turkey early Tuesday, sending people fleein g into the streets and collapsing some buildings, a private radio said. There were no immediate reports of casualties, private TGRT said. The radio said the epicenter of the quake was the city of Izm it, just east of Istanbul. The radio said some bridges and buildings collapsed and injuries were reported in Izmit, 65 miles east of Istanbul. The quake was strongly felt in Istanbul, where there were also reports of collapsed buildings, the radio said. The quake also s hook the capital Ankara, 270 miles to the east. Telephone and electrical service was cut in several areas as the quake struck at 3:02 a.m. (8:02 p.m. EDT), the radio said. AP-NY-08-16-99 2122EDT Copyright 1999 The Associated Press. The information contained in the AP news report may not be published, broadcast, rewri tten or otherwise distributed without prior written authority of The Associated Press. Announcement: America Online has added Reuters newswires to News Profiles. To add Reuters articles to your daily news delivery, go to KW: News Profiles and click on "Modify Your News Profiles." Then click "Edit" and add Reute rs from the list on the left. To edit your profile, go to keyword NewsProfiles. For all of today's news, go to keyword News. Subject: New event.... From: meredith lamb psnseismograph52@.......... Date: Mon, 16 Aug 1999 19:55:19 +0000 Wonder if it knocked out afew seismos in europe area? Am on the seismic chat site...for awhile... http://space.tin.it/scienza/frnucer/chatE.htm Still getting long period waves...not quite as smeared on the SDR as before. Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Expiration From: Larry Cochrane cochrane@.............. Date: Mon, 16 Aug 1999 19:11:59 -0700 Edward, Oops I forgot to increment the release number. As long as you don't get the time out message you should be OK. -Larry At 10:20 AM 8/16/99 -0600, you wrote: >Larry- > except the version identifies itself as 2.6.2 beta. >-Edward > >Larry Cochrane wrote: > >> Charlie, >> >> I have a new beta release, it's available on my system at >> http://www.seismicnet.com/software.html. This beta extends the time out >> period to the end of the year. I hope to make a real (non-beta) 2.6 release >> soon...As usual getting the documentation together is taking a longgggg >> time.... >> >> -Larry Cochrane >> Redwood City, PSN >> >> At 12:55 PM 8/12/99 -0400, you wrote: >> >Hello Larry, >> > >> >I notice I have about 3 days on your latest beta Winquake program >> >before it expires. Do you have an update available? >> > >> >Thanks a lot, >> > >> >Charlie Plyler >> >Elfrad Group >> > >> >> _____________________________________________________________________ >> >> 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) > >To leave this list email listserver@.............. with the body of the >message: leave PSN-L > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: EQ MAG 7.8 TURKEY From: The Lahrs JohnJan@........ Date: Mon, 16 Aug 1999 22:14:14 -0600 In case some on the PSN list are not aware of the NEIC's bigquake mailing list, here is a sample of the mail that is sent out following large earthquakes. At 7.8 we'll probably here more about the Turkey earthquake in the news tomorrow. This page: http://wwwneic.cr.usgs.gov/neis/data_services/data_services.html tells how to subscribe to the bigquake list. John >Return-Path: >X-Authentication-Warning: gldmutt.cr.usgs.gov: majord set sender to owner-bigquake@................... using -f >Date: Tue, 17 Aug 1999 3:42:52 GMT >From: MINSCH@................ >To: bigquake@................... >Subject: EQ MAG 7.8 TURKEY >Sender: owner-bigquake@................... >Reply-To: MINSCH@................ > > U.S. GEOLOGICAL SURVEY NATIONAL EARTHQUAKE INFORMATION CENTER > World Data Center A for Seismology > > Reply to: sedas@................. (internet) > sedas@................. (internet - alternate) > >The following is from the United States Geological Survey, National >Earthquake Information Center: Preliminary hypocenter for >earthquake of 1999 Aug 17, TURKEY: latitude 40.6 degrees north, >longitude 29.8 degrees east, origin time 00 01 38.6 utc, depth >shallow, magnitude 7.8 ms. There have been unconfirmed reports of >damage and possible casualties. >Stations used: ETER P 000616.0 ESEL P 000620.6 EROQ P 000636.7 >ETOR P 000655.7 ECRI P 000656.4 EVIA P 000704.5 ENIJ P 000706.0 >EHUE P 000706.8 ESDC P 000709.8 EBAN P 000713.6 ECOG P 000714.8 >EGUA P 000715.1 ELUQ P 000718.6 ELOJ P 000718.7 EHOR P 000723.3 >EPLA P 000723.7 EMON P 000726.7 ERUA P 000727.1 EJIF P 000729.3 >EVAL P 000735.2 STS P 000735.4 BGCA P 000847.5 LBTB P 001224.4 >BOSA P 001246.2 LBNH P 001253.3 INCN P 001257.4 LSCT P 001308.2 >SUR P 001311.7 BINY P 001314.5 COLA P 001319.4 TATO P 001323.5 >MCK P 001325.7 SSPA P 001326.1 MCWV P 001336.2 EYMN P 001336.3 >PMR P 001337.5 DIV P 001341.0 BLA P 001347.1 CEH P 001347.8 >JFWS P 001352.9 LHS P 001358.6 SIT P 001359.4 WCI P 001400.6 >MYNC P 001406.8 WVT P 001412.0 PWLA P 001416.5 OXF P 001422.0 >SFTN P 001422.0 NEW P 001424.1 DPW P 001427.6 STEW P 001433.6 >OCWA P 001434.4 RMW P 001434.9 CBKS P 001435.0 REDW P 001435.4 >HAWA P 001435.4 HAYW P 001435.9 LNOR P 001436.1 LON P 001438.0 >ISCO P 001440.7 HLID P 001441.2 HWUT P 001444.2 BDFB P 001446.0 >DAU P 001449.7 DUG P 001450.7 WVOR P 001451.5 PV08 P 001452.0 >PV09 P 001452.3 PV10 P 001455.0 MSU P 001459.1 BMN P 001500.0 >YBH P 001500.6 WDC P 001505.4 MNV P 001509.0 TPH P 001509.3 >OHCM P 001510.3 TPNV P 001513.3 CMB P 001513.5 MTUM P 001514.1 >LTX P 001516.4 DAC P 001517.9 TUC P 001520.4 PFO P 001526.9 >PLCA P 002033.0 CTAO P 002034.4 >-------------------------------------------------------------------------- >To unsubscribe from this email list send mail to: >majordomo@................... >and put >unsubscribe bigquake >in the body of the message. >Please leave the subject line blank when unsubscribing. >*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-* >SPECIAL NOTICE: The USGS is holding an Open House on August 27 & 28, 1999. >See: http://openhouse.cr.usgs.gov/ for all of the details. >-------------------------------------------------------------------------- > > John C. Lahr POB 1529 Golden, CO 80402 (303) 215-9913 http://lahr.org/john-jan I am only one, But still I am one. I cannot do everything, and because I cannot do everything, I will not refuse to do the something that I can do. Edward Everette Hale _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Turkey quake From: meredith lamb psnseismograph52@.......... Date: Mon, 16 Aug 1999 22:15:28 +0000 Tv news says N.W. Turkey, 7.1 mag, near a town call Islik (spelling). No news on NEIC or RedPuma on internet yet. Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Geophones From: aheerfor@...... Date: Tue, 17 Aug 1999 07:46:20 +0200 I am using some geophones to record strange ground vibrations which make a up a local hum phenomenon like the Taos Hum in the US. The recordings point toward a technical origin at a depth of 100 meters, possibly secret tunnels. But I have a practical problem: The stiff black geophone cabling is difficult to connect to my recording equipment. I have used XLR connectors, but when handling the cabling, the connectors sometimes break loose. The soldering is stressed, and it eventually breaks up. This is causing some failed recordings. How do you most easily make reliable connections? I have heard that geophones sometimes come with special connectors for seismic equipment, but I have never seen these connectors, and they may even be hard to find on the market. Perhaps these connectors are ideal; I don't know. Any opinions? Regards, Anders Heerfordt, Denmark _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: TURKEY MONSTER QUAKE From: "Francesco" franuc@...... Date: Tue, 17 Aug 1999 11:26:37 +0200 Hi to all, we have not posted the files yet, because the Italian isp, this night = was disable........sorry..... Now, I'm preparing a special page in the web, with all information about = the disaster. I will put in the most significant waveform of the PSN = member. Thank for the help. When the page is pubblicated I will notice to you. Francesco. IESN Italy p.s.: in some southern region of Italy the event is felt very well
Hi to all,
we have not posted the files yet, because the Italian isp, this = night was=20 disable........sorry.....
 
Now, I'm preparing a special page in the web, with all information = about=20 the disaster. I will put in the most significant waveform of the PSN=20 member.
 
Thank for the help.
 
When the page is pubblicated I will notice to you.
 
Francesco.  IESN Italy
 
 
p.s.: in some southern region of Italy the event is felt very=20 well
Subject: TURKEY SPECIAL PAGE From: "Francesco" franuc@...... Date: Tue, 17 Aug 1999 13:08:36 +0200 Hi all, It's on line the Turkey special page at = http://web.tiscalinet.it/iesn/turkey.htm I'm waiting other file from PSN members to insert in. This page is under updating. Regards Francesco
Hi all,
It's on line the Turkey special page at http://web.tiscalinet.i= t/iesn/turkey.htm
 
I'm waiting other file from PSN members to insert in.
 
This page is under updating.
 
Regards
Francesco
Subject: Re: TURKEY PAGE + Seismo Chat From: Arie Verveer ajbv@............ Date: Tue, 17 Aug 1999 20:47:20 +0800 Hi Francesco, Impressive response time with your report on the Turkey earthquake. It always distressing to hear that people died in these quakes. I should post my results, tomorrow. I had the day off from work were my seismograph is located. Though my automatic event mailer did e-mail me the recordings on the surface waves. Its a little program that e-mails me any event data that Larry's "SDR" program records. I need to do some more work on the program code but when its finished it should allow me to receive events while I'm on holiday. The data is sent on the hour if it exits. By the way, the seismo chat line now works with netscape 4.6. ? Arie _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Geophones From: Doug Crice dcrice@............ Date: Tue, 17 Aug 1999 07:39:41 -0700 Anders, Actually, the problem is not the black cable, which is a polyurethane jacket. The conductors themselves are made of "copperweld", which is an alloy of (I believe) steel and copper. The wire is much stronger and stiffer than normal copper wire. Both materials are chosen so that geophones can be used in the field handled by "juggies", folks not known to be gentle with seismic hardware. I watched a crew routinely toss geophones over the side of a stake truck onto concrete in downtown Los Angeles. A Sensor engineer once told me his geophones were designed to be dropped 50 feet from a helicopter. Geophone connectors are available, but the main problems they address are dirt and moisture, along with the aforementioned ruggedness issue. You can buy them from OYO Geospace or the Sensor Division of Input Output in Holland, but their distribution system is not geared to tiny orders. Anyway, because the wire is stiff, I would guess that flexing is breaking your solder bond. You need to use a connector with a rigid cable clamp so flexing of the wire doesn't translate down to the solder joint. Alternately, you can probably open up the geophones and substitute ordinary wire on that end. Be sure and observe the subtle polarity marks. For a quick and dirty solution, just splice some standard copper wire onto the geophone cable using one of those cylindrical wire splices. Because the copper wire will flex, that will relieve the stress on the joint. A crimp splice is more vibration resistant than a solder splice. Doug aheerfor@...... wrote: > > I am using some geophones to record strange ground vibrations which make a > up a local hum phenomenon like the Taos Hum in the US. > > The recordings point toward a technical origin at a depth of 100 meters, > possibly secret tunnels. > > But I have a practical problem: The stiff black geophone cabling is > difficult to connect to my recording equipment. I have used XLR connectors, > but when handling the cabling, the connectors sometimes break loose. The > soldering is stressed, and it eventually breaks up. This is causing some > failed recordings. > > How do you most easily make reliable connections? > > I have heard that geophones sometimes come with special connectors for > seismic equipment, but I have never seen these connectors, and they may > even be hard to find on the market. Perhaps these connectors are ideal; I > don't know. > > Any opinions? > > Regards, Anders Heerfordt, Denmark > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@.............. with the body of the > message: leave PSN-L -- 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) Subject: Re: Geophones From: jmhannon@.................... Date: Tue, 17 Aug 1999 10:03:02 -0500 Copperweld is copper clad steel piano wire, really nasty stuff. The crimp connection Doug reccoments is the best way to go. Jim Hannon Doug Crice on 08/17/99 09:39:41 AM Please respond to PSN-L Mailing List To: PSN-L Mailing List cc: Subject: Re: Geophones Anders, Actually, the problem is not the black cable, which is a polyurethane jacket. The conductors themselves are made of "copperweld", which is an alloy of (I believe) steel and copper. The wire is much stronger and stiffer than normal copper wire. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: TURKEY SPECIAL PAGE From: Edward Cranswick cranswick@........ Date: Tue, 17 Aug 1999 09:44:33 -0600 Francesco- Excellent response! -Edward Francesco wrote: > Hi all,It's on line the Turkey special page at > http://web.tiscalinet.it/iesn/turkey.htm I'm waiting other file from > PSN members to insert in. This page is under > updating. RegardsFrancesco -- 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". Francesco-
    Excellent response!
-Edward

Francesco wrote:

Hi all,It's on line the Turkey special page at http://web.tiscalinet.it/iesn/turkey.htm I'm waiting other file from PSN members to insert in. This page is under updating. RegardsFrancesco

--
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: Some notes to pass along... From: meredith lamb psnseismograph52@.......... Date: Tue, 17 Aug 1999 12:00:48 +0000 Hi all, 1. Apparently the Radio Shack DX-375 receiver is on sale this month. Regular price $99.00. On sale for $69.00 till August 28. Used for SDR card time. 2. Nuts & Volts magazine for July and August, Open Channel by Joseph J. Carr, has "Notes on Vibration Dectectors and Seismomgraphs - Part I and II. General article...not sure its worth buying...but Part II mentions the Lehman seismo. The article mentions sensors; and has acouple errors (like mounting the magnet on the boom)....but,..... Usually shows up on racks in some electronic wholesalers/retailers/electronic surplus outlets. Meredith Lamb .. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: 1999 USGS Open House notes From: meredith lamb psnseismograph52@.......... Date: Tue, 17 Aug 1999 12:30:38 +0000 > >SPECIAL NOTICE: The USGS is holding an Open House on August 27 & 28, 1999. > >See: http://openhouse.cr.usgs.gov/ for all of the details. > >-------------------------------------------------------------------------- > > > > > John C. Lahr > POB 1529 > Golden, CO 80402 > (303) 215-9913 > http://lahr.org/john-jan > > I am only one, But still I am one. > I cannot do everything, and because I cannot > do everything, I will not refuse > to do the something that I can do. > Edward Everette Hale > > The above reference by John Lahr, looks like a huge effort to acknowledge 150 years of the USGS. The August 27th Federal center is open mainly for school tours. The August 28th (Saturday) Federal Center exhibits is open to the general public. The website shows some SEVEN pages of exhibits at: http://openhouse.cr.usgs.gov/exhibits.html Check the site for maps, exhibits and notes. The August 28th USGS Open House in Golden is unique in that normally, it isn't open on Saturdays. I plan to see the National Geomagnetic Information Center...have never seen that. They removed the general exhibit in May for air conditioning work, and we'll see if its the same, or add on's have been made now. See: http://openhouse.cr.usgs.gov/golden.html Am planning on taking the digital camera along....perhaps leading to another series of web site references to pass some along. This looks like a very MASSIVE number of exhibits to see. The Golden and Federal Center sites are perhaps acouple miles apart. If you can come....it promises to be very unique. Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: PSN - Turkey From: "Rex Klopfenstein, Jr." rklopfen@......... Date: Tue, 17 Aug 1999 17:22:15 -0400 I have just posted my recording of the 00:01:38 quake in Turkey and uploaded to my website. I now am trying to come up with a scheme to calibrate my S-G's. I have been reading the "Manual of Seismological Observatory Practice" to get some ideas. I am going to write a procedure and post for better ideas. -- Rex Klopfenstein, Jr. Bowling Green, OH rklopfen@......... www.wcnet.org/~rklopfen _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Northern Cal event From: Larry Cochrane cochrane@.............. Date: Tue, 17 Aug 1999 18:14:48 -0700 All, While watching a news report on the terrible Turkey event we can a moderate local event. Heres the preliminary info 99/08/18 01:06:18 37.91N 122.69W 6.9 5.0Ml B* 0 mi SSW of Bolinas, CA The event was felt here in Redwood City. -Larry Cochrane Redwood City, PSN _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Northern Cal event From: fred@............ (Fred Bruenjes) Date: Tue, 17 Aug 1999 18:39:54 -0700 (PDT) >While watching a news report on the terrible Turkey event we can a moderate >local event. Felt it from my hotel room in San Jose - that was really wierd, I was also watching news on the 7.8 when my chair began wiggling! Lasted only a few seconds, and it wasn't enough to make me run for cover, but it definitely got my attention! Of course, my seismometer was turned off for this trip, so now I've missed both this and the Turkey quake. Bummer! Fred Bruenjes PSN Station #2 (Ramona, CA) -------------------------------------- Fred Bruenjes http://www.moonglow.net _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Y2K and an old Packard Bell 486 From: meredith lamb psnseismograph52@.......... Date: Tue, 17 Aug 1999 20:20:32 +0000 For those with old Packard Bell computers.... Finally got around to checking Y2K on an old 1993-94? Packard Bell 486 desktop computer. Instead of the usual date change check, I downloaded their Year 2000 Test Utilities & Remedies at web site: http://www.packardbell.com/y2k/pb/remedy.asp The program is downloaded and put on the hard drive. After reading the instructions, the machine is readied with another floppy which is loaded. Shutdown and restarting starts the test, which extends up to around the year 2008. The first result was that the machine failed; but could be manually set for 2000. Future years thereafter were also in doubt. Along the way, the program had a replacement file to try, and that was put on the system. The test continued and luckily it passed them all. The test program warned that date sensitive material could not be run 24 hours a day with the fix, with any kind of guarantee... 2000 and on will tell, if it really works with SDR.... Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Possible GPS glitch From: Greg ghost@............. Date: Tue, 17 Aug 1999 20:57:29 -0700 You might want to look into this if you're using a GPS receiver. Especially older civilian equipment. There's a story on CNN.com about this. The link from the story is below. The original story is on cnn.com. http://www.navcen.uscg.mil/gps/geninfo/y2k/default.htm ,Greg _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: step/sine auto-calibrator From: S-T Morrissey sean@........... Date: Tue, 17 Aug 1999 23:45:09 -0500 (CDT) Rex, I'm sorry I have not responded about the calibration board questions. It also brings up a point about seismometer calibration that I didn't mention earlier, namely using a bridge circuit with the main coil to introduce a calibration signal when a calibration coil is not available. (or has been burned out). This assumes that the main coil constant is known. Here is brief description of how the circuit is supposed to work; follow it on your schematic. The calibrator is designed to work in a bridge circuit with the main coil of an L4-C with the damping resistor installed across it. Hence the bridge balance pot R23 is 5k ohms. The calibration sequence is triggered by the "beep" of a 24-hour watch at pin 3; leads are soldered to the beeper and the case inside the watch. Before the availability of lithium batteries, the Hg watch battery was also trickle-charged by the calibration board (the dangling diode/resistor to pin 2). The watch ground is to pin 4. The 24-hour alarm is set for a night time hour; in a network, different times must be used to avoid loosing all the data if a quake should occur at a singular calibration time. The beep is rectified by a diode and amplified by U12 to provide a pulse that un-resets the oscillator and the dividers via U5.. The oscillator U1 outputs 2khz; divider U2 outputs 200hz, 60hz, and 20hz. Divider U3 outputs 1hz; the first 4017 U4 outputs 10 seconds, and U5 sequences the switches of U11, a 4066 quad switch. U7 and U8 form a 20-step sine generator, so sine frequencies of 10, 3 and 1 hz result from the switched inputs of 200, 60, and 20 hz from U2. Amplifier U13 buffers the switch outputs and filters the sine wave; Amplifiers U9 and U10 buffer and invert the signal to drive the calibration bridge. THe sequence is ended by U5 reasserting its pin 6. After the trigger or the test switch is activated, the sequence switch first applies a DC step to the calibration bridge for ten seconds, then turns it off. A 100k pot R14 controls the DC amplitude. Then there is a 10 second delay. The 20-step sine wave generator can be configured to have any two outputs like 3hz and 1 hz (or other combinations). These are sequentially switched in to the calibration bridge for 10 seconds each after the DC step. The sine amplitude is controlled by a 100k pot R13. Then C2/C3 remove the DC offset and amplifier U13 filters it.. The oscillator frequency can be changed to 200 hz, which divides all the frequencies and times by 10 for use with a long-period instrument. (C2 thru C9 need to be 10xed). The bridge balance pot is set by clamping the seis (by laying it on its side) and adjusting the amplifier output for a minimum signal. The switch manually starts the calibrator and holds it in the 3hz or 10hz sine wave mode for this adjustment. The sine amplitude is easy to set in this mode, but the 10-second DC step has to be set on the fly. In standby the current drain is about 50 microamps. I'm not sure what the current is when it is activated, but I think it is less than 1 ma.. I used to have fun shopping for a set of 20 or so watches for the trigger at places like Service Merchandise. The salesperson always wanted to know what I was going to do with 20 watches, so I simply said that I was going to bury them in the ground. They double checked my credit card! I hope this explains everything. I can provide the artwork for the 2.5" x 5.5" PC board (single sided) if anyone wants it. Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Local event From: Edward Cranswick cranswick@........ Date: Wed, 18 Aug 1999 08:44:06 -0600 Larry- I think it would be great if your records are used because I know how careful you are with the calibration and timing and your recording site is out there in Redwood City on the valley sediments of the Bay where we have few records, strong motion or otherwise. Similar sites underlain by unconsolidated sediments proved to be lethal in the Turkey Earthquake as they also did in the Marina District in the 1989 Loma Prieta Earthquake. I am leaving for Turkey on Friday. -Edward Larry Cochrane wrote: > Hi Lind, > > I heard your interview on channel 2 a few minutes ago, good job! I felt the > event very nicely while viewing a report on the terrible Turkey event. If > your seismologist need any more records to look at, for our local event, I > have some strong motion data and one on scale record from a L28. My other > sensors saturated.... The strong motion data is from a Kinemetrics FBA-23A > on loan from the local USGS. This sensor was calibrated about a year ago. > Timing for my event files are accurate to within a few milliseconds and is > referenced to WWV. I used GPS for my station location and should be > accurate to within 30-50 meters. I'm sure you guys have enough records too > look at but I thought someone there might be interested in the strong > motion data. > > Regards, > Larry Cochrane > Redwood City, PSN > > -- 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) Subject: Turkey on seismo viewer From: "Francesco" franuc@...... Date: Thu, 19 Aug 1999 01:43:49 +0200 I've updated the seimogram viewer java program with Turkysh event. I have choose at random, from all over the world, four file: one of italian station, one of Hawaii, one of Colorado and one of Texas. See at: http://web.tiscalinet.it/iesn/sve.html Regards Francesco p.s.: please, remember to push reload command (from window's men=F9 of = the applet) after the view of each file (for a large visualization).

I've updated the seimogram viewer java program with Turkysh=20 event.
I have choose at random, from all over the world, four file:
one of italian station, one of Hawaii, one of Colorado=20 and one of Texas.
 
See at: http://web.tiscalinet.it/= iesn/sve.html
 
Regards
Francesco
 
 
p.s.: please, remember to push reload command (from window's = men=F9 of=20 the applet) after the view of each file (for a large=20 visualization).
Subject: Izmit EQ From: jimo17@........ Date: Wed, 18 Aug 1999 17:29:16 -0700 Hi All, You can find the latest information on the Izmit EQ on this WEB page, a university and seismological observatory in Turkey. http://www.koeri.boun.edu.tr/earthqk/earthqk.html Date: 1999-08-17 at 03:01:37 , Surface Wave Magnitude: 7.8 Body Wave Magnitude: 6.3 Duration Magnitude: 6.7 Location: lots of maps, etc Seismicity of the Region Surface Faulting- The right lateral displacement offset of NAF between Sapanca Lake and Izmit Gulf was reported as 2.60m. Extent of the Damage-Lots of PIC's of damage, etc, Transportation Damages: Highway, Railway, Industrial Facilities: Damage areas in Istanbul and Turkey Peak Accelerations (only .3 g max!) Strong Motion Stations in Istanbul and the Marmara Region (I got this information from Prof. Barbara Luke, UNLV Engineering, who has a student visiting Istanbul) Jim O'Donnell _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Magnitude of Izmit event From: S-T Morrissey sean@........... Date: Thu, 19 Aug 1999 00:49:58 -0500 (CDT) Regarding the magnitude of the Izmit event; since there is some discussion as to what it really should be (aside from the various ways of expressing it:Mb,Ms,Ml,Mm, etc), curiosity suggests that the PSN see what its data provides. I don't know what WINQUAKE is giving for those who have it; I don't have it here. But everyone can use their own data and location to calculate Ms. To use a particularly generic formula, Gutenbergs' old formula is: Ms = log(A/P) + 1.66*log(distance) - 0.18. , where A is the p-p ground motion in nanometers (10^-9meter), P is the period in seconds, and the distance is in degrees. The value of the corrector term (-0.18) is subject to much debate, and has large regional variations. We can use the data from the STM-8B running here in the basement with the B version of the multi-period feedback set for 40 seconds, and digitizing with the RS multimeter set for 200mv full scale. The output of the VBB seismometer is 5,293 Volts/meter/second after the line driver. The signal actually clipped in the 12-bit digitizer during the surface waves at +,- 200 millivolts, or about 75 microns/second peak-peak. But graphic extrapolation of the plotted data gives a mean p-p amplitude of about 150 microns/second at 24 seconds, which is a displacement (multiplying 150 by 24/2*pi) of 572 microns or 5.72*10^5 nanometers.. Using a globe to get the distance, I find that western Turkey is about 120 degrees from St. Louis. So calculating the terms of the magnitude formula: log(A/P) = log[(5.72*10^5)/24] = 4.377 1.66*log(distance) = 1.66*log(120) = 3.45 So Ms = 4.377 + 3.45 - 0.18 = 7.65. Considering the uncertainties, this is pretty close. Changing the numbers by 10% changes the result by +,- 0.1 to 0.2 unit.. Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: More on the group sensor buy - final cost From: Larry Cochrane cochrane@.............. Date: Wed, 18 Aug 1999 23:17:45 -0700 All Geophoners, It looks like the final cost for the sensors will be $295.00 for the 1 hz device and $37.00 for the 4.5 hz sensor. These prices include the cost for shipping the sensors from Texas to Redwood City, Ca, but not the cost too ship the sensor to the user. I'm not sure what the weight is for the sensors, or what type of box and packing material I will need, so its hard to give an exact price. My guess is that for the 1 hz sensor shipping cost will be around $15.00 to $20.00 to addressed in the US, more for out of the country orders. Maybe a little less for orders here in California. For the 4.5 hz device the shipping cost should be about 1/2 the price. Too get the ball rolling lets do this. If you ordered one 1 hz sensor and you live in the US send me a check for $312.00. If you ordered one of the 4.5 hz device send me a check for $45.00. If the shipping cost ends up being a lot less or a lot more I will send you a refund or ask for more $. If you ordered more then one sensor the shipping cost should be a little less. I will contact you directly with a price. I will also contact you directly if you live outside of the US. Please make your check out to me and send it too: Larry Cochrane 24 Garden Street Redwood City, Ca. USA 94063 The order is going to be around $4500.00! Unfortunately I don't have that much money to write out a check and send it to Jim. So, when I get enough money together I will send Jim a check. When I receive the sensors I will check them out and send them too you. -Larry Cochrane Redwood City, PSN _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: LARGE QUAKE IN PROGRESS From: "Giovanni Rotta" rottag@.......... Date: Thu, 19 Aug 1999 17:33:05 +0200 Italian stations are recording a large quake new. Probably reply of Turkey - Giovanni Giovanni Rotta Via F. Pizzigoni, 10 33010 Resia (Udine) I Lat. 46.373 N Long. 13.305 E rottag@..........
Italian stations are recording a large quake=20 new.
Probably reply of Turkey -
Giovanni
 
Giovanni Rotta
Via F. Pizzigoni, 10
33010 = Resia=20 (Udine) I
Lat. 46.373 N  Long. 13.305 E
rottag@..........
Subject: R: LARGE QUAKE IN PROGRESS From: "Francesco" franuc@...... Date: Thu, 19 Aug 1999 18:04:35 +0200 Turkey aftershock Ml 4.9~ Francesco =FF=FE<=00!=00D=00O=00C=00T=00Y=00P=00E=00 =00H=00T=00M=00L=00 = =00P=00U=00B=00L=00I=00C=00 = =00"=00-=00/=00/=00W=003=00C=00/=00/=00D=00T=00D=00 =00H=00T=00M=00L=00 = =004=00.=000=00 = =00T=00r=00a=00n=00s=00i=00t=00i=00o=00n=00a=00l=00/=00/=00E=00N=00"=00>=00= =0D=00=0A= =00<=00H=00T=00M=00L=00>=00<=00H=00E=00A=00D=00>=00=0D=00=0A= =00<=00M=00E=00T=00A=00 = =00c=00o=00n=00t=00e=00n=00t=00=3D=00"=00t=00e=00x=00t=00/=00h=00t=00m=00= l=00;=00 = =00c=00h=00a=00r=00s=00e=00t=00=3D=00u=00n=00i=00c=00o=00d=00e=00"=00 = =00h=00t=00t=00p=00-=00e=00q=00u=00i=00v=00=3D=00C=00o=00n=00t=00e=00n=00= t=00-=00T=00y=00p=00e=00>=00=0D=00=0A= =00<=00M=00E=00T=00A=00 = =00c=00o=00n=00t=00e=00n=00t=00=3D=00"=00M=00S=00H=00T=00M=00L=00 = =005=00.=000=000=00.=002=000=001=004=00.=002=001=000=00"=00 = =00n=00a=00m=00e=00=3D=00G=00E=00N=00E=00R=00A=00T=00O=00R=00>=00=0D=00=0A= =00<=00S=00T=00Y=00L=00E=00>=00<=00/=00S=00T=00Y=00L=00E=00>=00=0D=00=0A= =00<=00/=00H=00E=00A=00D=00>=00=0D=00=0A= =00<=00B=00O=00D=00Y=00 = =00b=00g=00C=00o=00l=00o=00r=00=3D=00#=00f=00f=00f=00f=00f=00f=00>=00=0D=00=0A= =00<=00D=00I=00V=00>=00<=00F=00O=00N=00T=00 = =00s=00i=00z=00e=00=3D=002=00>=00T=00u=00r=00k=00e=00y=00 = =00a=00f=00t=00e=00r=00s=00h=00o=00c=00k=00<=00/=00F=00O=00N=00T=00>=00<=00= /=00D=00I=00V=00>=00=0D=00=0A= =00<=00D=00I=00V=00>=00&=00n=00b=00s=00p=00;=00<=00/=00D=00I=00V=00>=00=0D= =00=0A= =00<=00D=00I=00V=00>=00<=00F=00O=00N=00T=00 = =00s=00i=00z=00e=00=3D=002=00>=00M=00l=00 = =004=00.=009=00~=00<=00/=00F=00O=00N=00T=00>=00<=00/=00D=00I=00V=00>=00=0D= =00=0A= =00<=00D=00I=00V=00>=00&=00n=00b=00s=00p=00;=00<=00/=00D=00I=00V=00>=00=0D= =00=0A= =00<=00D=00I=00V=00>=00<=00F=00O=00N=00T=00 = =00s=00i=00z=00e=00=3D=002=00>=00F=00r=00a=00n=00c=00e=00s=00c=00o=00<=00= /=00F=00O=00N=00T=00>=00<=00/=00D=00I=00V=00>=00<=00/=00B=00O=00D=00Y=00>= =00<=00/=00H=00T=00M=00L=00>=00=0D=00=0A= =00 Subject: Re: step/sine auto-calibrator From: "Rex Klopfenstein, Jr" rklopfen@......... Date: Thu, 19 Aug 1999 13:41:02 -0400 Sean Thanks for the details of the calibration circuit. Mine appears to be working. I built it on a vector 'plug-in' card I found on my shelf. New question! I am looking at your seismic amplifier circuit and the photo of the pc cards (seispreamp.jpg) and have a question? What type of capacitor are used for the high pass filters (330mF) on the pictured boards? Thanks in advance -- Rex Klopfentein, Jr. rklopfen@......... http://www.wcnet.org/~rklopfen _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: S-G Calibration Scheme (LONG) From: "Rex Klopfenstein, Jr" rklopfen@......... Date: Thu, 19 Aug 1999 13:44:51 -0400 This is my idea of a calibration plan for my S-G seismometers. So look it over and shoot holes in it!! I am going to use a computer that has an A/D (12 bit) Board and LABview. I will plot the output of the S-G circuitry (high output) and plot voltage vs time. I can get fairly accurate readings of voltages and time using the LABView software. Most of my calibration plan comes from the "Manual of Seismological Observatory Practice". Keep in mind that this is pure theory, I haven't tried any of these procedures yet!! I am also going to disassemble my SGs and weight each pendulum and measrure center-of-gravity using a knife-edge or string loop. Measure the natural period: 1. Connect the S-G output to the data plotting system and install calibration coil (see my webpage). 2. Disconnect damping (I have a toggle switch on controller box). 3. Using leveling screws, adjust the voltage output to as close to 0 as possible (I have 1/4"-80 leveling screws). This can be roughed in using the 'tilt' LED on SG card (which I have moved to outside of box). 4. Set pendulum into oscillation by discharging a capacitor into calibration coil. 5. Record the the oscillations on plotting system. 6. Measure several periods and average to determine the apparent period T's. 7. Measure the amplitude of the waveform from the 0 line to peak and label each successive crossing of 0 line as a[1],a[2],...a[n]. 8. Calculate the mean value of logarithmic decrement L[r] = log[(a[r]+a[r=1])/(a[r+1]+a[r+2])] {log base 10}. I am a little unclear as to how to calculate the "mean value". The best I can come up with is to 'slide a window' three (3) samples wide down through the data and calculate the L for each 'stop'and then average these values. I have looked through my math books and found nothing on logarithmic decrement (anybody got a reference?). 9. Calculate the true period Ts = T's/(1+0.53/(L*L))**0.5. Measure static magnification: I have three leveling screws (1/4"-80) located in a triangular pattern. The distance from the back (2) leveling screws and the front (1) leveling screw is 10.00". If my trig is right, one turn of leveling screw is 0.00125 radian of tilt. I also plan to use a dial indicator to measure the actual lift of front edge of base and modify my trig accordingly. Also, the scheme I am using is described in the Manual of Seismological Observatory Practice to calibrate the magnification of the tilt of seismometer and mechanical indicator. I think it should work to give the magnification of the seismometer and the voltage output of the S-G board. Once I have that, I should be able to convert the voltage levels into SDR A/D units. I have a voltage calibrator at work that outputs voltage to three places to the right of decimal point. I plan to generate a series of readings and plot on spreadsheet. 1. Measure the natural period as above (Ts). 2. Connect the S-G output to the data plotting system and verify that damping is off. 3. Using front leveling screw, adjust the voltage output to as close to 0 as possible. 4. Apply a know tilt (single turn of leveling screw or via dial indicator) and record voltage level. 5. Keep increasing tilt until output (voltage) reaches level that indicates maximum travel (to be determined--maybe where the linearity falls apart). Record each step change in tilt and resoluting voltage level. Keep the step changes equal. 6. Return tilt to 0 volts. 7. Repeat step #5 with tilt in opposite direction. 8. Enter the recorded data into spreadsheet and generate calibration curve. 9. Calculate the undamped natural frequency Omega = (2*PI)/Ts 10. Solve for the static magnification (l/l') (l/l') = a/(tilt*g*Omege*Omega) a is voltage deflection g is gravity (9.81m/(s*s)) Now, this is where I am having a problem! I am now like the dog who chases cars, what am I going to do if I catch one! :). I now should have a binary_count_SDR/radian calibration factor or factors (if linearity too bad, maybe a piecewise linearization would help), how do I convert this into parameters that can be used to correlate data between stations?? Measuring Damping: 1. Reconnect damping. 2. Connect the S-G output to the data plotting system. 3. Install calibration coil. 4. Apply pulse to calibration coil by discharging a capacitor into it. 5. Record oscillations on plotting device. 6. Measure the elapsed (t)time from first peak of oscillation (a[1]) to the second peak on the other side of 0 line (a[2]). 7. Calculate normalized time (t') t' = omega*t 8. Calculate a[2]/a[1] to determine which curve to use in Fig 4.2.4 in Manual of Seismological Observatory Practice. Look up value of damping (Beta) based on proper curve and t'. According to Larry's SG Sensor Damping Adjustment instructions, the damping potentiometer should be set so that the oscillation should die away in about 1-1/2 cycles. This adjustment can be accomplished by using steps 1-5 until the waveform has proper decay and then continue to convert that setup into a damping factor. --------- Have mercy!! I am really a neophyte in the seismometer design area!! -- Rex Klopfentein, Jr. rklopfen@......... http://www.wcnet.org/~rklopfen _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Izmit Ms Calculation From: S-T Morrissey sean@........... Date: Thu, 19 Aug 1999 14:59:00 -0500 (CDT) Kevin Mackey has pointed out an error I made in the distance for the Izmit event. It appeared that I had not used the "Great Circle" distance; I had, but I measured and scaled it wrong. However, I was not pretending to do exact science at home; I have innumerable programs at the Univ for that. What I was trying to do was to show what a PSN member can do with home resources. I used a ruler on a globe as an approximation to determine the epicentral distance from St. Louis. The upper limit is of course the longitudinal distance, with St. Louis at 90W and the event at 29.8E. My antique globe has no scale on it, so I "calibrated" the ruler with the distance between St. Louis and San Francisco = 30 degrees, which led to over estimating the distance to Izmit. The actual STL to SFO distance is about 21 degrees. This makes my "ruler" say 84 degrees to Izmit; Kevin says it is 81 degrees. I should have suspected the error from the longitudinal information. The point is that simple, not so accurate measurements, are useful. At large distances, the effect of errors is not that significant. The difference in the calculated magnitude between 120 degrees and 81 degrees is 0.28. This reduces my magnitude estimate from 7.65 to 7.37, which is actually closer to todays' revised figure of 7.4. (I get 7.41 if I use 84 degrees!). I am more interested in how the amplitudes recorded by the PSN instruments worked out in determining the magnitude. Unfortunately, even large variables in the magnitude estimate provide no excuse for the hugh tragedy caused by shoddy building construction. Of course cement is expensive in that part of the world, but if only enough is used to keep the rain from washing out the mortar, it doesn't take much to shake down an apartment building. Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Grounding From: Dick Webb dwebb2@.............. Date: Thu, 19 Aug 1999 20:06:01 -0400 Well, my third board in 5 years has just bit the dust in an electrical storm and power outage. I have Larry's amp board in a vault out back and run wires, barely below the surface to my PC in the house. I also run a wire from the house to the vault for 110 volts. Both the incoming line and a line from the WWV antenna go to Larry's AtD board. That is the board that blew. The incoming line and the case I have the amp in are grounded or so it seems to me. Is there any way to protect the overall system or should I consider board replacement an operating expense. Dick Webb Raleigh, NC _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Grounding From: "jeremy t.l." tagrtfly@.......... Date: Thu, 19 Aug 1999 17:33:37 PDT try placeing fuseable links or build a circut breaker EX.like some bathroom outlets i haven ever had a problem with electronic going out in the many circut boards i have made so try it jeremy lange Fruita, colorado ________________________________________________________________ Get FREE voicemail, fax and email at http://voicemail.excite.com Talk online at http://voicechat.excite.com _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Grounding From: David Josephson david@............. Date: Thu, 19 Aug 1999 17:42:50 -0700 (PDT) > that blew. The incoming line and the case I have the amp in are grounded > or so it seems to me. Is there any way to protect the overall system or > should I consider board replacement an operating expense. Dealing with lightning currents is just like dealing with noise in board design, just bigger. You should have a lightning rod, grounded to its own ground stakes (3 of them, a foot apart, 10 feet deep, minimum) and this setup should be as far away from your instrumentation as possible. Then be sure that the lowest resistance path from your vault ground, rack ground, etc. to the same ground stakes is via a thick wire that's run as far away from your signal wires as possible. The input leads should be twisted as tightly as possible to eliminate loop area for magnetic coupling of the surge to the inputs of the gear. Finally you should look at the input circuitry of whatever blew up and protect it with gas tubes and/or MOV type surge suppressors, each routed to the same ground stake. Wide copper strap from the earth stake to your cold water system is good too. -- David Josephson / Josephson Engineering / San Jose CA / david@............. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Grounding From: SW6079@....... Date: Thu, 19 Aug 1999 21:07:13 EDT Well, If you can handle some more info, these ideas may help. I lost the preamps to two fairly expensive Ham receivers before trying these ideas... Basically, Nothing will save you on a direct hit, But I installed two zener diodes across the coaxial cable nearest the ground connection outside. I believe I used 5.1 volt zeners, 1 watt rating. I wired them in parallel, one with its anode on the antenna hot lead, the other with its cathode on the hot lead.. the other leads going to the shield of the coaxial cable. I believe that you could even use a lower value w/ Larry's boards (ie 3.3 volt) without upsetting the circut operation. I am certain that in at least one case they did the job, as one day after a nasty storm my receiver would not work with the antenna lead connected. I investigated and found one of the zeners had shorted! I also use a lightning arrester (which is really nothing more than a spark gap) However it takes upwards of a thousand static volts usually to make one of these arc.... You can well imagine that your sensitive electronic equipment will protect the spark gap by conducting first!! Good luck Mike. sw6079@....... N7ORL _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Grounding From: JIm Hannon jmhannon@........ Date: Thu, 19 Aug 1999 20:56:59 -0500 SW6079@....... wrote: > Well, If you can handle some more info, these ideas may help. I lost the > preamps to two fairly expensive Ham receivers before trying these ideas... > Basically, Nothing will save you on a direct hit, But I installed two zener > diodes across the coaxial cable I keep seeing the statement "nothing will save you from a direct hit" I would agree more with the statement "nothing will save you from every direct hit". Radio and TV towers often get hit every storm. The hits may trip the station off line until someone pushes the reset button, but most of the time no permanent damage is done. We designed some radio equipment for unatended operation in a very remote and thunder storm prone area. All the electronics are in a rf tight metal cabinet with all wires entering the cabinet protected with several layers of arrestors and surge protectors. One time one of these units stopped working. When the service tech got there he found the coax leading the cabinet was nothing but a plastic tube. All the copper had been evaporated. He replaced the coax and everything worked fine. I suppose at some point it may not be worth the expense for this level of protection. I am still struggeling with a lightning problem here at home. I go thru surge protectors like popcorn. The last storm all the electrolumenescent night lights I have blew. Jim Hannon _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Grounding From: "Rex Klopfenstein, Jr" rklopfen@......... Date: Fri, 20 Aug 1999 08:25:31 -0400 You might look into the line protection schemes used in industrial/phone lines that are buried. You can get lighting strikes via underground line. A number of manufactures sell devices that protect these lines from lighting strikes. Go to the library and look up manufactures of lighting suppressor in the Thomas Register. You might look at companys that specialize in protectors for RSXXX line are 4-20mA current loops. I have seen devices that hang off of each line and are connected to ground (they must be mounted outside and away from device to be protected. Dick Webb wrote: > Well, my third board in 5 years has just bit the dust in an electrical > storm and power outage. I have Larry's amp board in a vault out back and > run wires, barely below the surface to my PC in the house. I also run a > wire from the house to the vault for 110 volts. Both the incoming line and > a line from the WWV antenna go to Larry's AtD board. That is the board > that blew. The incoming line and the case I have the amp in are grounded > or so it seems to me. Is there any way to protect the overall system or > should I consider board replacement an operating expense. > > Dick Webb > Raleigh, NC > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@.............. with the body of the > message: leave PSN-L -- Rex Klopfentein, Jr. rklopfen@......... http://www.wcnet.org/~rklopfen _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Grounding From: "Rex Klopfenstein, Jr" rklopfen@......... Date: Fri, 20 Aug 1999 08:25:31 -0400 You might look into the line protection schemes used in industrial/phone lines that are buried. You can get lighting strikes via underground line. A number of manufactures sell devices that protect these lines from lighting strikes. Go to the library and look up manufactures of lighting suppressor in the Thomas Register. You might look at companys that specialize in protectors for RSXXX line are 4-20mA current loops. I have seen devices that hang off of each line and are connected to ground (they must be mounted outside and away from device to be protected. Dick Webb wrote: > Well, my third board in 5 years has just bit the dust in an electrical > storm and power outage. I have Larry's amp board in a vault out back and > run wires, barely below the surface to my PC in the house. I also run a > wire from the house to the vault for 110 volts. Both the incoming line and > a line from the WWV antenna go to Larry's AtD board. That is the board > that blew. The incoming line and the case I have the amp in are grounded > or so it seems to me. Is there any way to protect the overall system or > should I consider board replacement an operating expense. > > Dick Webb > Raleigh, NC > > _____________________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email listserver@.............. with the body of the > message: leave PSN-L -- Rex Klopfentein, Jr. rklopfen@......... http://www.wcnet.org/~rklopfen _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Mag. calc. From: robert barns 75612.2635@.............. Date: Fri, 20 Aug 1999 10:48:45 -0400 Sean-Thomas, Thanks for the detailed calculation example of Ms for the Turkey 'quake= and the STM-8B. Impressive agreement! I haven't been able to figure out= how you get the "p-p amplitude at 24 seconds" from your seismogram. Bob Barns _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Grounding From: Karl Cunningham karlc@....... Date: Fri, 20 Aug 1999 09:32:59 -0700 Dick -- One thing that may not have been mentioned is to run the signal wires inside *metal* conduit, grounded at both ends (as well as you can). Also, don't run the 110V power lines in the same conduit. A nearby lightning strike could put a large spike on the power lines, which could couple into the signal lines. I agree with the suggestion of zener diodes across the signal lines. Zeners are very fast at turing on and good-sized ones will dissipate a very large amount of power for a short time. Put them at the amp input and keep the leads short to improve high-frequency response. Karl Cunningham La Mesa, CA. PSN station #40 karlc@....... At 08:06 PM 8/19/1999 -0400, you wrote: >Well, my third board in 5 years has just bit the dust in an electrical >storm and power outage. I have Larry's amp board in a vault out back and >run wires, barely below the surface to my PC in the house. I also run a >wire from the house to the vault for 110 volts. Both the incoming line and >a line from the WWV antenna go to Larry's AtD board. That is the board >that blew. The incoming line and the case I have the amp in are grounded >or so it seems to me. Is there any way to protect the overall system or >should I consider board replacement an operating expense. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Grounds! From: Mike Lozano mikel@....... Date: Fri, 20 Aug 1999 13:57:07 -0500 I've been following the discussion on 'grounding' with a great deal of interest. What's becoming plainly obvious is that there are many misconceptions which are being perpetuated in this forum. One of those misconceptions is that 'grounding' is a D.C. phenomenon, measured as a resistance. It's not! When speaking of 'ground resistance' we're actually speaking of 'ground impedance' or resistivity. This 'resistance' can only be measured with special equipment, using the 'fall of potential' technique. This type of equipment is manufactured by companies such as Biddle and AEMC, to name but a few; and, it may be possible to ask your local power company or lightning protection company to check your ground rods for the proper 'resistance'.=20 The resistance issue has clouded the field of grounding, and is best demonstrated by the 'more is better' school of thought. These proponents hold that if one ground rod is good, then multiple ground rods are better =85. the 'more then merrier' school. At first blush, thi= s technique seems to make sense. The confusion stems from confusing 'ground resistance' with 'resistance' in D.C. analysis. While in D.C. analysis, resistors in parallel decrease the total resistance to less than the value of the least one, this is most definitely not true when multiple ground rods are considered! In fact, when driving multiple ground rods; they should be driven no closer together than twice the length of a single rod. Although beyond the scope of a short note, the reason the 'more the merrier' is not a valid ground resistance reduction technique has to do with mutual inductance between the rods. As to the placement of signal leads in conduit, care must be taken that ground currents flowing through the conduit walls don't couple currents into the conductors encased within. In short, this technique creates a linear transformer! As to the prevention of dangerous voltages reaching a sensitive instrument, a multiple protection scheme must be used. T he principal idea is to provide both 'common' and 'differential' mode protection. For example, take two signal lines referenced to 'ground'.=20 Common mode transients take both lines 'high' in respect to 'ground'.=20 Differential mode transients, on the other hand, take one line, or the other 'high' in respect to the other two. If it'll make it a bit clearer, consider the case of a common A.C. surge suppressor. It you take one apart, you'll find three Metal Oxide Varistors, or MOVs inside. One MOV goes from the Black wire to the White wire. This is the differential mode protector. The two MOVs going from the Black and White wire to the Green or 'ground' to provide common mode protection. The exact, same principle can be used to protect any number of signal lines. One fellow asked if replacement boards are to be considered a normal expense. The answer is, most assuredly not! I've designed and installed the common/differential protection scheme to protect several Doppler Radar installations in the Midwest, as well as in the South.=20 These radar systems are located on frequently struck television transmitting towers. At from one million to several hundred thousand dollars a pop, my clients simply can't afford to replace these systems; but it's simple to replace the protection circuits about every five years, or so. As to the use of zener diodes - they are fast, but not too sturdy. In the cases mentioned above, I've used triple protection! A current limiting agent in the form of a fast-acting thermistor; an MOV and a gas-filled spark gap. I've found that the MOV (only slightly slower than a zener) is more than adequate protection. For most signal lines, I use an MOV rated at 12 Volts, with the highest possible Joule ratings. As for the gas-filled spark gap, I use a CG75L manufactured by C.P. Clare Co. This small device fires at approximately 60 volts, and while slower than an MOV, can handle tremendous amounts of power. Of course none of these protection schemes will work well without a good quality grounding system. For the industrial installations I've performed, ranging from petroleum transfer stations, to 250 foot tall water towers with telemetry and two-way radio antennae at the top, I insist on no more than five ohms of ground resistance as measured with a Biddle ground resistivity meter, using the three lead, 'fall of potential' method.=20 Just plunking a rod in the ground does not guarantee a good ground! If you want to construct a ' relatively good quality ground', dig a hole about the size and depth of a five gallon bucket. The ground wire should be NO SMALLER than #4 copper stranded wire. Attach that to a =BD inch to =BE inch thick grounding rod, at least 8 to 10 feet long. Drive the rod into the ground so that the top of the rod is level with the bottom of the hole. Then, dig a channel about three inches across, and three inches deep around the circumference of the bottom of the hole.=20 Into the channel, pour ice cream salt until the channel is filled.=20 Then, fill the hole with dirt; moisten it down and then tamp it down.=20 Every few days add water to make sure than the salt dissolves slowly. =20 The salt will enhance the ground's 'conductivity'! =20 When connecting to the ground lead, make sure there are no kinks or short bends in the cable. Kinks and bends represent inductance, which tends to lessen the quality of the ground by raising the impedance.=20 If there's any interest, I'll try to put a JPG diagram of the protection scheme I use, on my company website at: http://www.sciencearea.com I also have a small quantity of gas-filled spark gaps left over from a project. I'd be glad to make these available to the PSN members at cost, plus shipping. Regards to all, Mike Lozano, Meteorologist / Engineer NSLI Certified Lightning Safety Professional Applied Sciences, Ltd. -0- _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: seismogram amplitude From: S-T Morrissey sean@........... Date: Fri, 20 Aug 1999 14:23:10 -0500 (CDT) Bob, Yor asked about determining the amplitude of ground motion from a seismogram: For the case of the STM-8: since this is a triple VBB system, the sensitivity is determined by the transfer function. For the flat portion of the response, the constant output level is equal to 1/(G*Cp), where G = Gn/M and Cp is the feedback capacitor value. For the STM-8 (or any other moving coil seismometer, including the SG), Gn is the constant of the feedback coil, namely the speaker coil and magnet. It is determined by zeroing the sensor (using the displacement detector), adding a small mass, like 1 gram, and using a potentiometer to control a small current (from AA battery) to lift the boom back to center. This results (for the B instrument) in 0.830ma to lift 1 gram, so Gn = (1gram/0.830ma)*9.8m/sec^2 = 11.815 Newtons/Ampere. Now M = 0.5kgrams, so G = 23.63. With Cp = 20 microfarads, or 0.00002 farad. So k = 1/G*C = 1/(23.63*0.00002) = 2116 volts/meter/second. THis is the output over the whole flat portion of the response, from 40 seconds (or whatever the long period corner of the VBB is set at) to 30 hz. So it can be used for any period output in between. The electronics has a "line driver" amplifier with a gain of X5. This is more than I need to see the background 6-second microseisms, so I divide it by two with external resistors. So the signal to my digitizer is 5290 V/m/sec = 5.29V/mm/sec = 5.29millivolt/micron/sec.. SO what did the "seismogram" show? In this case the data is from the RS 12-bit multimeter digitizer. Operating at a scale of 200mv, full scale is 37.8 microns/second or 75 microns/sec p-p. When I plotted the seismogram, I could extrapolate the clipped surface waves for an estimate of the actual p-p value of 150 microns/second. Again, note that the flat VBB response means that this value is valid for any waveform from 40 seconds (the current Tn selection) to 30 hz. I can measure the period of the maximum sustained waveform (which is used for the Ms calculation) from the seismogram plot as 5 cycles over 120 seconds = 24 seconds. The Ms calculation needs the p-p ground amplitude in nanometers. To convert the velocity of 150microns/second into displacement, it is divided by (w)omega = 2*pi/P, where P is the period. So 150/w = 150*24/(2*pi) = 573 microns, or 5.73*10^5 nanometers. This means that the p-p ground motion at St. Louis from the Izmit event was about 0.57 millimeters. Plugging this into the magnitude formula: Ms = log(A/P) + 1.66*log(distance) - 0.18 Ms = log(5.73*10^5/24) + 1.66*log(81degrees) -0.18 Ms = 4.378 + 3.17 - 0.18 Ms = 7.37 Hopefully you will get a similar result with your data. For a conventional moving coil seismometer, the output is not flat, so the sensitivity at each period must be determined. Often this is determined from a log-log graph of the calibration, which is usually determined with a calibration coil or signal bridge and a function generator. Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: More on the group sensor buy - final cost From: Doug Niessen dniessen@........... Date: Fri, 20 Aug 1999 16:54:12 -0700 Hi Larry, My check will be mailed tomorrow. I'm in Folsom CA so it should be there next week. Thank you for taking the time and effort to make these purchases. Thanks, Doug p.s. If you ever have a need for hydrophones, let me know. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: questions on strong motion and pepp systems From: Doug doug@............. Date: Sat, 21 Aug 1999 11:51:28 -0700 greetings qfolks, I am setting up a seismic station here in the santa cruz mountains of northern CA. I am very close (~1 mile) from the san andreas fault line and also very close to the bedrock. I will be starting out with the 1hz and 4.5z geophones from the group buy. Because I am close to an active fault, I would like to add some strong motion sensors. I wonder if anyone has recommendations on sources for these. I don't want to spend thousands on these but I am willing to spend $500-$1000. Does anyone know what I can get in this price range, or where I can get them? I am also wondering if any of you folks use your seismic data to trigger emergency shut off of gas, electricity, etc. Given my location it is inevitable that the ground will shake violently at some point in the future, and I'd like to set up something that would shut off my main propane valve, electricity to selected devices, etc. If anyone is aware of commercial sensors designed to trigger this, or if you have any ideas on this subject, I would appreciate the help. I also have a 75 gallon marine reef aquarium here, and I keep having these visions of water pouring out all over the place. I am wondering if there is something I could do to help make the aqauarium resilient to shaking, as in making a custom stand that would shield the aquarium from the vibrations underneath. Any ideas? One other question, the PEPP broadband system for $1500 looks quite interesting. I am wondering if anyone out there is using this system, and if so I'd like to hear some opinions about your experience with it. I am wondering if I would be better off going with strong motion sensors next, or instead adding the PEPP system to my station. If you were here literally on the edge of the san andreas fault line on the bedrock, which would you choose to do? TIA, Doug _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Epicenter Location From: Arie Verveer ajbv@............ Date: Sun, 22 Aug 1999 11:47:38 +0800 Hi, I have had some remarkable success with winkquake in predicting the location of an epicentre for a few local quakes. Using the Kalamunda station and two autodrum stations, it has been possible to locate an epicentre within 5 km of the quoted value. Though our depth of these quake are highly likely to be around 5 km. But you need a good "P" and "S" wave for the prediction. I would like to write or use a program that can locate a quake using the "P" waves. Can anyone help in locating a program, code or a source of information on how this is done? I guess a least squares equation is involved but the way depth is calculated eludes me. Any ideas. Arie _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Analog Devices & Strong Motion Arrays From: Doug doug@............. Date: Sun, 22 Aug 1999 04:11:27 -0700 Earlier I asked about strong motion sensors, both for local seismic data recording, and also for triggering gas shutoff. Someone sent me the URL for an eval kit from analog devices: http://www.analog.com/techsupt/eb/EB-232_B.pdf This kit looks really interesting, it has a simple RS232 connection and comes with software that graphs acceleration. Would definitely be easy to experiment with. It looks like this chip is being used for seismic switches http://www.analog.com/iMEMS/products/ADXL202_top.html Here's an article about using these for seismic recording http://www.analog.com/publications/whitepapers/products/Seismart.html This article talks about using these low cost accelerometers in large arrays. This sounds really interesting. Does anyone know if these are really being used for strong motion arrays? Is this $15 accelerometer really good enough to gather useful strong motion data? It's definitely an interesting concept, using low cost parts in large numbers. It will soon be possible to ethernet-enable these things for really cheap, like $15. I'd like to explore this idea further, so I'm going to get the eval kits for the ADXL202 and ADXL105 and see if I can get one of these individual accellerometers on the web. I have on order some SIMM-sized microcontrollers that have ethernet, I/O processor and RTOS, plus serial and parallel ports, CAN bus, and 1-wire microlan. Each module has its own IP address and implements TCP/IP, PPP, HTTP, FTP, and TELNET. Imagine if you could build a node of a strong motion array for $50, with all of these internet protocol interfaces. You could then plug them into ethernet 10-base-t concentrators, and have really easy ways to get at the data from large numbers of sensors. You could plug them into any existing network and browse their data at any time from anywhere in the world. You could telnet to them, transfer files, and even use ppp for communications. Does this sound interesting to anyone? Has anyone done something similar? I'm thinking about taking one of my SIMM-sized boards and trying to interface it to one of the low-cost analog devices accelerometers. The cool thing is that when I'm done, it will have its own IP address and will be hanging off my local 10-base-t LAN which routes to the Internet. You will actually be able to browse the sensor itself. The total cost of the prototype will be about $60. If the data is useful I can make a large array for really cheap. In fact I can plug them in anywhere that I can find a 10-base-t network. I guess that would make it a world wide array. Things that make you go hmmm ... -- Doug (seismic newbee but networking professional) PS. Please share your opinions on the Analog Devices accellerometers. Are these good enough to provide useful srong motion data in large arrays? Or are they really only suited to emergency switching? _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: lightning protection From: S-T Morrissey sean@........... Date: Sun, 22 Aug 1999 14:17:21 -0500 (CDT) Here is some further info about lightning protection from many years of win and lose experience.. In operating seismic telemetry stations with VHF transmitters it is obvious that the antenna in the tree or tower is the lightning rod, and the seismometer buried in the ground is the ground rod (or will try to be). So successful lightning protection is essential to equipment survival. In general, we have had more losses of the VHF radio transmitter than of the telemetry electronics itself. There were also notable disasters, like when the lightning arced right through the 1/4" ABS pipe vault from the case of the L4-C to ground. (There is no rule that lightning has to even LIKE my grounding system and use the ground rod properly!). But for the most part the equipment survives. Unfortunately, one never knows for sure when the protection works; only popped fuses, transistors, amplifiers and smoked boards say it didn't. So the protection is multi-level and inserted in any power or signal interconnection, including the coaxial line to the antenna and the DC power controllers for the solar panels. It only takes about 20 volts to burn out the RF output transistor of the radio transmitter which runs at 14 volts, so a system based on 18 volt MOVs is needed.. Until the advent of MOVs (metal oxide varistors) transorbs were the device of choice. These are essentially high power zeners designed to take a surge, and actually have a dissipation rating in joules. They are expensive, hard to test (without blowing them), and give no external sign that they are in fact blown. But they are fast, since they have low capacitance. So MOVs are preferred, since they clearly self destruct if their power rating is exceeded.. But they are also large capacitors, so they are slow. This requires some delay element (usually an inductor) to force the surge voltage to rise and fire the protection devices. Inductors are also used to isolate a VHF signal from the lower frequency transient. I generally use several levels of protection, including the 60-volt gas discharge devices (available from Newark, Mouser, etc, for under $3.) These latter may not protect a 12-volt transistor, but will help reduce the physical damage when the lower voltage MOVs are overwhelmed, such that the repair may only involve replacing the transistor. For capacitance-sensitive applications, like a 50-ohm antenna feed, a small 70-volt neon bulb will work. I installed them at the UHF or N connector of all the VHF transmitters and receivers. They tend to explode if overloaded. I have also found that lightning suppression systems should not be built on a printed circuit board; the lightning just flashes across the surface, vaporizing the foils. I use high-barrier terminal strips with point-to-point wiring. Cleanliness is also important also; dried sweat is a good conductor. Fuses are installed in-line by using the GJV type inside clear shrink tube, connected with crimp connectors. They are used in both sides of the DC power and signal (both siesmic and FM carrier) lines.These limit the damage when the protection devices conduct the surge to ground. For testing the lightning protection, we use a small electric fence transformer. It could spark across an 1/8" air gap. We use a 110v lamp in series with the AC primary to limit the power. For the ground rod, standard copperweld rods are used; since my stations are in generally wet areas (Southern Missouri, the Aleutians, etc), I have not needed to salt the ground as Mike L. recommends. But location of the rod is important; it should provide as direct a path from the antenna's coaxial feed to the ground at the base of the tower. For a building, the rod should be installed as close to the probable entry location of any lightning. Most buildings have the lightning ground rod installed right under the electrical meter. The electrical panel ground may also be connected to the cold water pipe. I there is further interest, I can scan the circuits I use, particularly those used with the seismic amplifiers and telemetry. Another note about protecting the AC line: I have had unlimited success using ferroresonant constant voltage transformers to block transients on the incoming AC line. These are made by Sola, etc, and are expensive, costing about $1 per watt of capacity. But they will not pass any power other than a 60 hz sine wave. They last almost forever, so finds at surplus stores usually work. After about 20 years the resonating capacitor fails and the insulation dries out, since they run hot.. They have no "moving parts", like the relays in the inexpensive switched line regulators, and will put out 110 volts from an input of 90 to 140 volts. But, as I said, their main virtue is that they only output a 60 hz sine wave. I have used one at a key telemetry station with 200ft tower since 1972, and have never had any lightning damage. I have also been at the 'head-end" building of a cable TV system, where we rent space 300ft up on the tower, when lightning has hit the tower, and everything survives, including the local seismometer/telemetry unit. Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Epicenter Location From: The Lahrs JohnJan@........ Date: Sun, 22 Aug 1999 13:34:22 -0600 At 11:47 AM 8/22/99 +0800, Arie wrote: >I would like to write or use a program that can locate >a quake using the "P" waves. Can anyone help in locating >a program, code or a source of information on how this is >done? Arie, One possibility would be to use the program Hypoellipse which is available from this site. There are PC/DOS and SUN/UNIX versions available. http://lahr.org/iaspei/northam/ak/s_ak/programs/hypoel/hypoel.html Cheers, John John C. Lahr POB 1529 Golden, CO 80402 (303) 215-9913 http://lahr.org/john-jan I am only one, But still I am one. I cannot do everything, and because I cannot do everything, I will not refuse to do the something that I can do. Edward Everette Hale _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Epicenter Location From: Larry Cochrane cochrane@.............. Date: Sun, 22 Aug 1999 20:28:52 -0700 Hi Arie, Also part of the IASPEI software package is a DOS program called XRTP. This is a data logging program, but it also has some event location capabilities. One advantage is its written in C, not FORTRAN like Hypoellipse. I started too pull out the location code but stopped after finding out it only works with local events. I figured if I was going to spend the time adding this to WinQuake I would try and find something that could be used for all type of events... If you get something working please let me know. I'll see if I can add it to WinQuake. I will send you the source code in a private email message. -Larry Cochrane Redwood City, Ca. At 11:47 AM 8/22/99 +0800, you wrote: >Hi, I have had some remarkable success with winkquake >in predicting the location of an epicentre for a few local >quakes. Using the Kalamunda station and two autodrum >stations, it has been possible to locate an epicentre >within 5 km of the quoted value. Though our depth of these >quake are highly likely to be around 5 km. But you need >a good "P" and "S" wave for the prediction. > >I would like to write or use a program that can locate >a quake using the "P" waves. Can anyone help in locating >a program, code or a source of information on how this is >done? I guess a least squares equation is involved but the >way depth is calculated eludes me. > >Any ideas. > >Arie > > > > >_____________________________________________________________________ > >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) Subject: Re: Analog Devices & Strong Motion Arrays From: aheerfor@...... Date: Mon, 23 Aug 1999 07:38:41 +0200 > PS. Please share your opinions on the Analog Devices accellerometers. Are these good enough to provide useful srong motion data in large arrays? Or are they really only suited to emergency switching? < The latter. I have a number of these devices. S/N ratio is really poor, making them useless for seismic use. Regards, Anders _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Analog Devices & Strong Motion Arrays From: Arie Verveer ajbv@............ Date: Mon, 23 Aug 1999 19:54:17 +0800 Hi Doug, Sorry I cant help on you seismic shut off system but I do express an interest in the the micro controller with its own "IP" address and implements TCP/IP ++++. I remember an article in "Dr. Dobbs" about a real-time weather station made by a company called: http://www.pharlap.com/ If you have more info on the manufactures address, that would be great. Interesting possibilities. - good idea. Regards Arie Doug wrote: > > I have on order some SIMM-sized microcontrollers that have > ethernet, I/O processor and RTOS, plus serial and parallel > ports, CAN bus, and 1-wire microlan. Each module has its > own IP address and implements TCP/IP, PPP, HTTP, FTP, and > TELNET. Imagine if you could build a node of a strong > motion array for $50, with all of these internet protocol > interfaces. You could then plug them into ethernet 10-base-t > concentrators, and have really easy ways to get at the data > from large numbers of sensors. You could plug them into any > existing network and browse their data at any time from > anywhere in the world. You could telnet to them, transfer > files, and even use ppp for communications. Does this sound > interesting to anyone? Has anyone done something similar? > > I'm thinking about taking one of my SIMM-sized boards and > trying to interface it to one of the low-cost analog devices > accelerometers. The cool thing is that when I'm done, it will > have its own IP address and will be hanging off my local > 10-base-t LAN which routes to the Internet. You will actually > be able to browse the sensor itself. The total cost of the > prototype will be about $60. If the data is useful I can > make a large array for really cheap. In fact I can plug > them in anywhere that I can find a 10-base-t network. I > guess that would make it a world wide array. Things that > make you go hmmm ... _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Lightning Protection From: wizard@......... (Rick Jerome) Date: Mon, 23 Aug 1999 05:10:32 -0700 I have a good book on lightning protection from Polyphaser Corp that I found valuable for this type of information. The book covers everything from theory to practical techniques to protect equipment. We have used the information in this publication to protect our telemetry sites at work. Title: The Grounds fo Lightning and EMP Protection Author: Roger R. Block Polyphaser Corp 1425 Industrial Way Gardnerville, Nevada 89410-1237 _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: More on the geophone group buy. From: "Warren Shedrick" warren@.......... Date: Mon, 23 Aug 1999 10:04:36 -0700 > Date: Sun, 15 Aug 1999 22:50:03 -0700 > To: psn-l@.............. > From: Larry Cochrane > Subject: More on the geophone group buy. > Reply-to: PSN-L Mailing List > All, > > I contacted Jim Croix at Mitcham Industries to see how many of the 1 hz and > 4.5 hz sensors he has. He has 40-50 of each type of sensor, so everyone who > contacted me can get one. > > This is what I have so far for the group buy: > > Who Qt Sensor Type > David Okrent 1 4.5 hz > Terence Dowling 1 1 hz > Arie Verveer 1 1 hz > Tom Frey 1 1 hz > Doug at los-gatos.net 1 1 hz > Larry Cochrane 1 1 hz > > If you want to be added to the list please let me know ASAP. I will contact > Jim in a few days to get a final price for the equipment. > > 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 > Sorry for the late reply, I have been on vacation. I am interested in (1) 1Hz geophone Thank you Warren Shedrick _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Analog Devices & Strong Motion Arrays From: Doug doug@............. Date: Mon, 23 Aug 1999 10:18:05 -0700 I aksed about the Analog Devices accelerometers: > Please share your opinions on the Analog Devices > accellerometers. Are these good enough to provide > useful srong motion data in large arrays? Or are > they really only suited to emergency switching? Anders wrote: >The latter. > >I have a number of these devices. S/N ratio is really poor, >making them useless for seismic use. Which ones do you have, the ADXL05s? They have two new models ADXL105 (replaced ADXL05) and ADXL202. I am wondering if these have better performance. Also, I am on the fault line in a quiet area, so I am wondering if that makes a difference. It is a complete waste of time trying these for strong motion? Assuming that the ADXL devices are not useful, does anyone have any other recommendations for accelerometers that would yield a better S/N ratio? Or any other strong motion sensor to complement my 1hz and 4.5hz geophones? Thanks, Doug _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Analog Devices & Strong Motion Arrays From: Doug doug@............. Date: Mon, 23 Aug 1999 10:23:39 -0700 Arie wrote: >Hi Doug, Sorry I cant help on you seismic shut off system >but I do express an interest in the the micro controller >with its own "IP" address and implements TCP/IP ++++. > >[snip] > >If you have more info on the manufactures address, that >would be great. Interesting possibilities. - good idea. http://www.ibutton.com/TINI/ -- Doug _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Analog Devices & Strong Motion Arrays From: jmhannon@.................... Date: Mon, 23 Aug 1999 13:15:18 -0500 > Please share your opinions on the Analog Devices > accellerometers. Are these good enough to provide > useful srong motion data in large arrays? Or are > they really only suited to emergency switching? Doug, It depends on what exactly you want to record. Your geophones should be good for most local events up to the point of felt shaking. The Analog Devices accelerometers overlap this a little bit and would then be good up to the point of total destruction. I can't find the reference just now but I think I read that the recent quake in Turkey had accelerations of up to 0.3 G. That and much weaker are within the capabilities of the Analog Devices parts. Jim Hannon _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Analog Devices & Strong Motion Arrays From: aheerfor@...... Date: Mon, 23 Aug 1999 20:57:27 +0200 > Which ones do you have, the ADXL05s? < Yes > They have two new models ADXL105 (replaced ADXL05) and ADXL202. I am wondering if these have better performance. < From my study of the data sheets, I gather that they don't have a significantly better performance. >Also, I am on the fault line in a quiet area, so I am wondering if that makes a difference. < It does. You may get stronger motion than here. I am far from any fault line. > It is a complete waste of time trying these for strong motion? < No, the devices are fine for strong motion. Say, when you are at the epicenter. And when your seismometers are driven into saturation. Bruel and Kjaer make many fine accellerometers. One of these has an extremely fine S/N ratio compared to other accellerometers. Regards, Anders _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Analog Devices & Strong Motion Arrays From: aheerfor@...... Date: Mon, 23 Aug 1999 21:06:26 +0200 For a sensitive accellerometer, look at: High Sensitivity Accelerometer Type 8318-C. see web page http://www.bk.dk/5000/5223.htm Regards, Anders _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Analog Devices & Strong Motion Arrays From: Doug Crice dcrice@............ Date: Mon, 23 Aug 1999 12:03:17 -0700 jmhannon@.................... wrote: > > > Please share your opinions on the Analog Devices > > accellerometers. Are these good enough to provide > > useful srong motion data in large arrays? Or are > > they really only suited to emergency switching? > > Back in my youth, there was a maximum theoretical acceleration from an earthquake of a fraction of a g. Then the Piocama (sp?) Dam earthquake recorded 1.01 g on bedrock. This was a good sized earthquake, but not big enough to inspire memories like the 1972 or Loma Prieta earthquakes. I would think that sitting up on the fault you could get some stuff well within the range of sensitivity of that accelerometer. You'll have to wait a while, but your geophones are going to be useless when it happens and you'll feel bad if you don't get a decent recording of your own personal event. Regarding that fish tank, it's going to have serious problems. Down here in Saratoga (10 miles North) we had waves over 6 feet in my swimming pool and lost about two feet of water from the last Loma Prieta earthquake. I'm not sure of the solution, maybe suspend it from rubber bands from the ceiling and put on a cover. Don't forget that most strong-motion seismographs fail because the batteries are dead, you will not have any power when it hits, so maybe one of those computer power supplies is in order. -- 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) Subject: Re: Analog Devices & Strong Motion Arrays From: John Lahr lahr@................... Date: Mon, 23 Aug 1999 14:23:51 -0600 (MDT) Doug, You wrote, "Assuming that the ADXL devices are not useful, does anyone have any other recommendations for accelerometers that would yield a better S/N ratio?" Here's a message that I put on the PSN back in April. John Evans is using these sensors for seismic recording - although I'm not sure which model is currently preferred. JCLahr >Because of the possible interest to PSN members, >I've put a copy of John Evans' USGS Open-file Report on >The Design and Performance of a Low-cost Strong-motion >Sensor onto the following web page: > >http://geohazards.cr.usgs.gov/evans/ofr_98_109.html > >This address will work for the next few weeks, but >eventually John E. will be moving the report to a USGS web >server in Menlo Park. The bulk of the report is in PDF format; >free readers are available here: > >http://www.adobe.com/prodindex/acrobat/readstep.html > >in case you don't have one already. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Analog Devices & Strong Motion Arrays From: Doug doug@............. Date: Mon, 23 Aug 1999 15:45:12 -0700 Jim wrote: > It depends on what exactly you want to record. I want to record only local events, and I'd like to get as much useful data on these events as reasonably possible without spending thousands on individual sensors. I guess the real question I have is this: what would be a good combination of sensors for this purpose? I am getting both the 1hz and 4.5hz geophones as per the group buy. This leaves me one extra channel on the amp/filter board, so I am wondering which type of additional geophone would be good to add as a third? Then, in addition to geophones, I am looking for other strong motion sensors that would be good for local recording, as a complement to the geos. > Your geophones should be good for most local events up to the point > of felt shaking. Okay, that is good, since I should detect the smaller local activity. > The Analog Devices accelerometers overlap this a little bit and would > then be good up to the point of total destruction. Well I think they are fine for me then. I understand that they will not be useful at all for teleseismic events, and therefore are not what most amateurs would want to use. But in my case they might be good for local activity (only during large events). Let's hope I don't get to the point of total destruction any time soon :) Since I can get the ADXL202s and ADXL105s in the form of cheap and easy eval boards, I think I'll set up a few of them here, and work towards connecting them to a microcontroller with ethernet as I described earlier. Analog also provides free samples so I already have some of these freebies on the way. If anything it should help me to learn about accelerometers, and sanity test the sensor <--> ethernet idea. It sure would be neat to have say 16 of these plugged directly into a 10-base-T hub, each with their own IP address and embedded web server. I could have one of my unix boxes run a cron job and grab the data logs. Also, I could use flash ROM on the microcontrollers to aid in saving data in the event of a complete power outage. One thing I like about the ADXL202 is that it has digital output, therefore requiring no A/D conversion, and easy to connect to a microcontroller or other host. In the meantime I got some suggestions for sources other more sensitive accelerometers. Thanks everyone for all the help. This stuff is very, very interesting. -- Doug _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Analog Devices & Strong Motion Arrays From: Doug doug@............. Date: Mon, 23 Aug 1999 16:12:43 -0700 Correction wrt my last post: > Also, I could use flash ROM on the microcontrollers to aid in saving > data in the event of a complete power outage. I meant to say flash disk, not flash ROM, which is obviously read only. -- Doug _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Event? From: barry lotz gbl@....... Date: Tue, 24 Aug 1999 19:41:01 -0700 I picked up a fairly large regional event around 13:10 UTC 8/24/99. I checked the live Internet seismic server and it shows up in New Mexico. NEIS has a very short list at this time.It doesn't show up there. Has anyone in California picked this event up? Barry _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Event? From: Seisguy@....... Date: Tue, 24 Aug 1999 23:23:51 EDT In a message dated 08/24/1999 7:40:42 PM Pacific Daylight Time, gbl@....... writes: << I picked up a fairly large regional event around 13:10 UTC 8/24/99. I checked the live Internet seismic server and it shows up in New Mexico. NEIS has a very short list at this time.It doesn't show up there. Has anyone in California picked this event up? Barry >> It was on the NEIS list before it wigged out this morning. M4.7 13:04 UTC location 51 miles south of Yuma, AZ Mike _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Hypoellipse From: Arie Verveer ajbv@............ Date: Wed, 25 Aug 1999 23:45:16 +0800 Hi, After a recent e-mail to the "PSN" list, I received three great answers to my question relating to the location of an epicentre. Dr. John Lahr suggested that his program, hypoellipse may be of interest. After setting the velocity model for my location and inputting data for my station and two AutoDrm stations, the program calculated the epicentre of a local quake, (within 0.002 of a degree!) and that is compared to an "A" class position. The program is very flexible and I do recommend its use. You will need to down load the files from : http://lahr.org/iaspei/northam/ak/s_ak/programs/hypoel/hypoel.html Thanks, Dr. John Lahr for this great resource. Arie _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: NEW RESIA' SEISMIC WEB SITE From: "Giovanni Rotta" rottag@.......... Date: Wed, 25 Aug 1999 22:27:42 +0200 Hi ! I have the pleasure to present to you the new seismic web site of my = seismic station. The new adress is http//www.resianet.org/ingssr.htm Regards, Giovanni=20 =20 Giovanni Rotta Via F. Pizzigoni, 10 33010 Resia (Udine) I Lat. 46.373 N Long. 13.305 E rottag@..........
Hi !
I have the pleasure to present to you the new = seismic web=20 site of my seismic station.
The new adress is=20 http//www.resianet.org/ingssr.htm
Regards,
Giovanni 
 
Giovanni Rotta
Via F. Pizzigoni, 10
33010 = Resia=20 (Udine) I
Lat. 46.373 N  Long. 13.305 E
rottag@..........
Subject: SORRY... THE REAL NEW RESIA' SEISMIC WEB SITE From: "Giovanni Rotta" rottag@.......... Date: Wed, 25 Aug 1999 22:39:17 +0200 Sorry!... A mistake in my e-mail... :-))) The new adress in http//www.resianet.org/sismo01.asp Regards, Giovanni Giovanni Rotta Via F. Pizzigoni, 10 33010 Resia (Udine) I Lat. 46.373 N Long. 13.305 E rottag@.......... http://www.resianet.org/sismo01.asp
Sorry!... A mistake in my e-mail... = :-)))
The new adress in=20 http//www.resianet.org/sismo01.asp
Regards,
Giovanni
 
Giovanni Rotta
Via F. Pizzigoni, 10
33010 = Resia=20 (Udine) I
Lat. 46.373 N  Long. 13.305 E
rottag@..........
http://www.resianet.org/sism= o01.asp
Subject: R: Hypoellipse From: "Francesco" franuc@...... Date: Thu, 26 Aug 1999 01:02:59 +0200 Hi Arie. Some months ago I've downloaded the Hypoellipse, but I found a lot of = difficulty to compile the program (I'm not so pratic in these = programs......). =20 Certainly, this program is useful for the location of local events and I = would try to use it for our Italian network. =20 Now, my great problem is to understand how to configure the station list = (stations.dat ???) in according with the severlas parameters indicated = in the explanation....(calibration, gain, ecc.ecc.....). Which is the input file???? If possible to use our type of file (SDR or = WQ) for Hypoellipse? If yes, how can I do? And more: how can I modify the travel model? I seem that you have used soon this programm without any difficult. Can you help me ????? From now, thank you very very much Francesco =FF=FE<=00!=00D=00O=00C=00T=00Y=00P=00E=00 =00H=00T=00M=00L=00 = =00P=00U=00B=00L=00I=00C=00 = =00"=00-=00/=00/=00W=003=00C=00/=00/=00D=00T=00D=00 =00H=00T=00M=00L=00 = =004=00.=000=00 = =00T=00r=00a=00n=00s=00i=00t=00i=00o=00n=00a=00l=00/=00/=00E=00N=00"=00>=00= =0D=00=0A= =00<=00H=00T=00M=00L=00>=00<=00H=00E=00A=00D=00>=00=0D=00=0A= =00<=00M=00E=00T=00A=00 = =00c=00o=00n=00t=00e=00n=00t=00=3D=00"=00t=00e=00x=00t=00/=00h=00t=00m=00= l=00;=00 = =00c=00h=00a=00r=00s=00e=00t=00=3D=00u=00n=00i=00c=00o=00d=00e=00"=00 = =00h=00t=00t=00p=00-=00e=00q=00u=00i=00v=00=3D=00C=00o=00n=00t=00e=00n=00= t=00-=00T=00y=00p=00e=00>=00=0D=00=0A= =00<=00M=00E=00T=00A=00 = =00c=00o=00n=00t=00e=00n=00t=00=3D=00"=00M=00S=00H=00T=00M=00L=00 = =005=00.=000=000=00.=002=000=001=004=00.=002=001=000=00"=00 = =00n=00a=00m=00e=00=3D=00G=00E=00N=00E=00R=00A=00T=00O=00R=00>=00=0D=00=0A= =00<=00S=00T=00Y=00L=00E=00>=00<=00/=00S=00T=00Y=00L=00E=00>=00=0D=00=0A= =00<=00/=00H=00E=00A=00D=00>=00=0D=00=0A= =00<=00B=00O=00D=00Y=00 = =00b=00g=00C=00o=00l=00o=00r=00=3D=00#=00f=00f=00f=00f=00f=00f=00>=00=0D=00=0A= =00<=00D=00I=00V=00>=00<=00F=00O=00N=00T=00 = =00s=00i=00z=00e=00=3D=002=00>=00H=00i=00 = =00A=00r=00i=00e=00.=00<=00/=00F=00O=00N=00T=00>=00<=00/=00D=00I=00V=00>=00= =0D=00=0A= =00<=00D=00I=00V=00>=00<=00F=00O=00N=00T=00 = =00s=00i=00z=00e=00=3D=002=00>=00S=00o=00m=00e=00 = =00m=00o=00n=00t=00h=00s=00 =00a=00g=00o=00 =00I=00'=00v=00e=00 = =00d=00o=00w=00n=00l=00o=00a=00d=00e=00d=00 =00t=00h=00e=00 = =00H=00y=00p=00o=00e=00l=00l=00i=00p=00s=00e=00,=00 =00b=00u=00t=00 = =00I=00 =00f=00o=00u=00n=00d=00 =00a=00 =00=0D=00=0A= =00l=00o=00t=00 =00o=00f=00 = =00d=00i=00f=00f=00i=00c=00u=00l=00t=00y=00&=00n=00b=00s=00p=00;=00 = =00t=00o=00 =00c=00o=00m=00p=00i=00l=00e=00 =00t=00h=00e=00 = =00p=00r=00o=00g=00r=00a=00m=00 =00(=00I=00'=00m=00 =00n=00o=00t=00 = =00s=00o=00 =00p=00r=00a=00t=00i=00c=00 =00i=00n=00 = =00t=00h=00e=00s=00e=00 =00=0D=00=0A= =00p=00r=00o=00g=00r=00a=00m=00s=00.=00.=00.=00.=00.=00.=00)=00.=00&=00n=00= b=00s=00p=00;=00 = =00<=00B=00R=00>=00C=00e=00r=00t=00a=00i=00n=00l=00y=00,=00 = =00t=00h=00i=00s=00 =00p=00r=00o=00g=00r=00a=00m=00 =00i=00s=00 = =00u=00s=00e=00f=00u=00l=00 =00f=00o=00r=00 =00t=00h=00e=00 = =00l=00o=00c=00a=00t=00i=00o=00n=00 =00o=00f=00 =00=0D=00=0A= =00l=00o=00c=00a=00l=00 =00e=00v=00e=00n=00t=00s=00 =00a=00n=00d=00 = =00I=00 =00w=00o=00u=00l=00d=00&=00n=00b=00s=00p=00;=00 =00t=00r=00y=00 = =00t=00o=00 =00u=00s=00e=00 =00i=00t=00 =00f=00o=00r=00 =00o=00u=00r=00 = =00I=00t=00a=00l=00i=00a=00n=00 = =00n=00e=00t=00w=00o=00r=00k=00.=00&=00n=00b=00s=00p=00;=00 =00=0D=00=0A= =00<=00/=00F=00O=00N=00T=00>=00<=00/=00D=00I=00V=00>=00=0D=00=0A= =00<=00D=00I=00V=00>=00<=00F=00O=00N=00T=00 = =00s=00i=00z=00e=00=3D=002=00>=00<=00/=00F=00O=00N=00T=00>=00&=00n=00b=00= s=00p=00;=00<=00/=00D=00I=00V=00>=00=0D=00=0A= =00<=00D=00I=00V=00>=00<=00F=00O=00N=00T=00 = =00s=00i=00z=00e=00=3D=002=00>=00N=00o=00w=00,=00 =00m=00y=00 = =00g=00r=00e=00a=00t=00 =00p=00r=00o=00b=00l=00e=00m=00 =00i=00s=00 = =00t=00o=00 =00u=00n=00d=00e=00r=00s=00t=00a=00n=00d=00 =00h=00o=00w=00 = =00t=00o=00 =00c=00o=00n=00f=00i=00g=00u=00r=00e=00 =00t=00h=00e=00 = =00=0D=00=0A= =00s=00t=00a=00t=00i=00o=00n=00 =00l=00i=00s=00t=00 = =00(=00s=00t=00a=00t=00i=00o=00n=00s=00.=00d=00a=00t=00 = =00?=00?=00?=00)=00 =00i=00n=00 =00a=00c=00c=00o=00r=00d=00i=00n=00g=00 = =00w=00i=00t=00h=00 =00t=00h=00e=00 =00s=00e=00v=00e=00r=00l=00a=00s=00 = =00p=00a=00r=00a=00m=00e=00t=00e=00r=00s=00 =00=0D=00=0A= =00i=00n=00d=00i=00c=00a=00t=00e=00d=00 =00i=00n=00 =00t=00h=00e=00 = =00e=00x=00p=00l=00a=00n=00a=00t=00i=00o=00n=00.=00.=00.=00.=00(=00c=00a=00= l=00i=00b=00r=00a=00t=00i=00o=00n=00,=00 =00g=00a=00i=00n=00,=00 = =00e=00c=00c=00.=00e=00c=00c=00.=00.=00.=00.=00.=00)=00.=00<=00/=00F=00O=00= N=00T=00>=00<=00/=00D=00I=00V=00>=00=0D=00=0A= =00<=00D=00I=00V=00>=00<=00F=00O=00N=00T=00 = =00s=00i=00z=00e=00=3D=002=00>=00W=00h=00i=00c=00h=00 =00i=00s=00 = =00t=00h=00e=00 =00i=00n=00p=00u=00t=00 = =00f=00i=00l=00e=00?=00?=00?=00?=00 =00I=00f=00 = =00p=00o=00s=00s=00i=00b=00l=00e=00 =00t=00o=00 =00u=00s=00e=00 = =00o=00u=00r=00 =00t=00y=00p=00e=00 =00o=00f=00 =00=0D=00=0A= =00f=00i=00l=00e=00 =00(=00S=00D=00R=00 =00o=00r=00 =00W=00Q=00)=00 = =00f=00o=00r=00 =00H=00y=00p=00o=00e=00l=00l=00i=00p=00s=00e=00?=00 = =00I=00f=00 =00y=00e=00s=00,=00 =00h=00o=00w=00 =00c=00a=00n=00 =00I=00 = =00d=00o=00?=00<=00/=00F=00O=00N=00T=00>=00<=00/=00D=00I=00V=00>=00=0D=00=0A= =00<=00D=00I=00V=00>=00<=00F=00O=00N=00T=00 = =00s=00i=00z=00e=00=3D=002=00>=00A=00n=00d=00 =00m=00o=00r=00e=00:=00 = =00h=00o=00w=00 =00c=00a=00n=00 =00I=00 =00m=00o=00d=00i=00f=00y=00 = =00t=00h=00e=00 =00t=00r=00a=00v=00e=00l=00 = =00m=00o=00d=00e=00l=00?=00<=00/=00F=00O=00N=00T=00>=00<=00/=00D=00I=00V=00= >=00=0D=00=0A= =00<=00D=00I=00V=00>=00&=00n=00b=00s=00p=00;=00<=00/=00D=00I=00V=00>=00=0D= =00=0A= =00<=00D=00I=00V=00>=00<=00F=00O=00N=00T=00 = =00s=00i=00z=00e=00=3D=002=00>=00I=00 =00s=00e=00e=00m=00 = =00t=00h=00a=00t=00 =00y=00o=00u=00 =00h=00a=00v=00e=00 = =00u=00s=00e=00d=00 =00s=00o=00o=00n=00 =00t=00h=00i=00s=00 = =00p=00r=00o=00g=00r=00a=00m=00m=00 =00w=00i=00t=00h=00o=00u=00t=00 = =00a=00n=00y=00 =00=0D=00=0A= =00d=00i=00f=00f=00i=00c=00u=00l=00t=00.=00<=00/=00F=00O=00N=00T=00>=00<=00= /=00D=00I=00V=00>=00=0D=00=0A= =00<=00D=00I=00V=00>=00<=00F=00O=00N=00T=00 = =00s=00i=00z=00e=00=3D=002=00>=00C=00a=00n=00 =00y=00o=00u=00 = =00h=00e=00l=00p=00 =00m=00e=00 = =00?=00?=00?=00?=00?=00<=00/=00F=00O=00N=00T=00>=00<=00/=00D=00I=00V=00>=00= =0D=00=0A= =00<=00D=00I=00V=00>=00&=00n=00b=00s=00p=00;=00<=00/=00D=00I=00V=00>=00=0D= =00=0A= =00<=00D=00I=00V=00>=00<=00F=00O=00N=00T=00 = =00s=00i=00z=00e=00=3D=002=00>=00F=00r=00o=00m=00 =00n=00o=00w=00,=00 = =00t=00h=00a=00n=00k=00 =00y=00o=00u=00 =00v=00e=00r=00y=00 = =00v=00e=00r=00y=00 = =00m=00u=00c=00h=00<=00/=00F=00O=00N=00T=00>=00<=00/=00D=00I=00V=00>=00=0D= =00=0A= =00<=00D=00I=00V=00>=00&=00n=00b=00s=00p=00;=00<=00/=00D=00I=00V=00>=00=0D= =00=0A= =00<=00D=00I=00V=00>=00<=00F=00O=00N=00T=00 = =00s=00i=00z=00e=00=3D=002=00>=00F=00r=00a=00n=00c=00e=00s=00c=00o=00<=00= /=00F=00O=00N=00T=00>=00<=00/=00D=00I=00V=00>=00<=00/=00B=00O=00D=00Y=00>= =00<=00/=00H=00T=00M=00L=00>=00=0D=00=0A= =00 Subject: I: Hypoellipse From: "Francesco" franuc@...... Date: Thu, 26 Aug 1999 15:49:02 +0200 John and Arie. Some problem with the server for the last message.... I repost it. Francesco -----Messaggio Originale----- Da: Francesco A: PSN-L Mailing List Data invio: giovedě 26 agosto 1999 1.02 Oggetto: R: Hypoellipse Hi Arie. Some months ago I've downloaded the Hypoellipse, but I found a lot of difficulty to compile the program (I'm not so pratic in these programs......). Certainly, this program is useful for the location of local events and I would try to use it for our Italian network. Now, my great problem is to understand how to configure the station list (stations.dat ???) in according with the severlas parameters indicated in the explanation....(calibration, gain, ecc.ecc.....). Which is the input file???? If possible to use our type of file (SDR or WQ) for Hypoellipse? If yes, how can I do? And more: how can I modify the travel model? I seem that you have used soon this programm without any difficult. Can you help me ????? From now, thank you very very much Francesco _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Hypoellipse From: John Lahr lahr@................... Date: Thu, 26 Aug 1999 09:19:53 -0600 (MDT) Hello Francesco, I would be happy to help you get hypoellipse going for your local and regional seismicity. What platform (IBM PC or UNIX) are you using? If PC or SUN UNIX then you will not need to recompile the program. The manual is quite fat, but if you print out Chapter 2 it will help with many questions. This is not the easiest program to run, so don't hesitate to ask me, also. Good luck, 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) Subject: Evans' reports From: John Lahr lahr@................... Date: Thu, 26 Aug 1999 11:13:00 -0600 (MDT) Hi Doug, As you read, John Evans is breaking some new ground with the new acceleration sensors. To get to the reports that John Evans mentioned, first ftp andreas.wr.usgs.gov Then cd pub/outgoing/jrevans/OFR_98_109 for the first report, and cd pub/outgoing/jrevans/OFR_98_586 for the second one. I've also put PDF and MS WORD97 versions of the first report here: http://geohazards.cr.usgs.gov/evans/ofr_98_109.html Good luck with your monitoring! JCLahr ****** >From: "John R. Evans" >To: doug@............. >Subject: Strong motion for Santa Cruz mountain home Doug, I have a design for a good but relatively inexpensive (ca. $500 parts for three components) strong-motion sensor. You will need four channels (the fourth for temperature) if you use it. Do an old-fashioned anonymous ftp() to andreas.wr.usgs.gov and retrieve either the PC (.zip) or the Unix (.Z's) version of USGS Open-file Report 98-109 (design), and possibly 98-586 (what we're doing with them in Oakland): /ftp/pub/outgoing/jrevans/OFR_98_109 /ftp/pub/outgoing/jrevans/OFR_98_586 PEPP would be interesting and useful too (Susan Schwartz at UCSC would like some teleseismic records, I'm sure, to look at anisotropy) but strong-motion is my passion (and bias!). The PEPP instrument will peg, I believe, for strong motion. Either way, good luck. --John jrevans@........ Doug, Just got down to your follow-up message, again forwarded to me by John Lahr. The ADXL devices are certainly adequate for shut-off valves and a microcontroller with them could be used to trigger on something more subtle than peak acceleration (peak velocity is a better predictor of damage, for example). We would not sneeze at records from them either, but they are rather noisy by our standards and really only about a 9-bit sensor (when comparing broadband peak-to-peak noise to a +/-2 g relevant range in earthquakes ... well, some say +/-3 g is wiser very close to a fault). Useful, but the design I sent you in the previous e-mail is a true 16-bit sensor and therefore produces much more valuable seismograms. It can be stretched beyond the +/-2 g limit, but the maker does not guarantee linearity (probably adequate to +/-2.5 g anyway). My TREMOR Project is aimed at something similar to your sug- gestion for a strong-motion instrument at many internet nodes. It looks like the spatial variability of shaking requires an instrument at least every km to get a decently accurate map of shaking strength. We're currently using CDPD (cell phone internet) but I have serious doubts about its reliability after a big event (mainly because ground lines to the cell phone base stations are vulnerable). A more robust private telemetry, such as ISM spread spectrum, is a better long-term solution. We are currently exploring a particularly interesting version. Stay tuned. Good luck, John jrevans@........ _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: R: Hypoellipse From: "Francesco" franuc@...... Date: Fri, 27 Aug 1999 01:12:16 +0200 I use a PC-dos. Our network is based on eight stations all around Italy, equiped with 3 components (z 1hz, e/w n/s); Larry's ampli-board and a/d 16 bit; SDR and Wq software. I read chapter 2, but, until now I have not understod which file and how I must modify it to accord the several parameters. About the input file? Thank Francesco _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: R: Hypoellipse From: "Francesco" franuc@...... Date: Fri, 27 Aug 1999 01:12:16 +0200 I use a PC-dos. Our network is based on eight stations all around Italy, equiped with 3 components (z 1hz, e/w n/s); Larry's ampli-board and a/d 16 bit; SDR and Wq software. I read chapter 2, but, until now I have not understod which file and how I must modify it to accord the several parameters. About the input file? Thank Francesco _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Hypoellipse From: Arie Verveer ajbv@............ Date: Fri, 27 Aug 1999 11:17:13 +0800 Hi Francesco, I'm just a novice in getting it to work, but I'll Zip all the files that I used and write a brief description on how it was approached. I'll be away for about day, but when I get back I'll get the info together. In the mean time, I would suggest to copy all the files relating to Hypoellipse for "DOS" from Dr. John Lahr's site. Especially the "Quick start manual" (quikstrt.doc or quikstrt.pdf) and "Quickrun files". Placing them in a separate folders. See you in a day or so. Arie _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: calibration: log decrement From: S-T Morrissey sean@........... Date: Fri, 27 Aug 1999 12:34:41 -0500 (CDT) Rex, Regarding your notes on calibrating yout SG sensors. The "Manual of Seismological Observatory Practice" was a major accomplishment at its release in 1970 and is still certainly a very useful reference. However, as the editors note, it was being updated even as it was being published, and some of the contents have since been significantly updated. In particular, some of the instrumentation specifications and formula were revised for the WWNSS (worldwide network of standardized stations), so the information in the WWNSS manual became preferred. The sections on record content and earthquake parameter determination are quite good. The instrumentation formulas involving galvanometers and coupling circuits are obviously no longer applicable, but complicate the basic seismometer formulas.. You asked about the "logarithmic decrement" mentioned in paragraph 4.1.3. I cannot verify the formulas found there, since they propose be for using log(10), rather than the natural log ln, which is always used to define the function, since the amplitude of the damped oscillation decays as e^-hwnt. This can be found in other seismic instrumentation notes (Eaton, Kisslinger, Bullen (pg 148), as well as in: "Advanced Engineering Mathematics": by Erwin Kreyszig. Pg115: The ratio of two consecutive maximum amplitudes a1 and a2 of a damped oscillation is constant. The natural logarithm of this ratio is the logarithmic decrement d, where: ln(a1/a2) = d = 2*pi*a/w*, where a = c/2*m and w* is omega*. c being the damping constant, m the mass, and w* the damped period. This method is used to determine the open-circuit damping of seismometers. In the conventions of seismic instrumentation, where h = the damping ratio to critical (h = 1 at critical) (B, l or L is often used in place of h for the damping ratio) a1/a2 = xm/x(m+1) = exp (2*pi*h/sqrt(1-h^2)), and the decrement is then d = ln(xm/x(m+1) = 2*pi*h/sqrt(1-h^2) Often several successive zero-crossings are used to get a mean value. Or several values of d are determined and averaged. Depends on your program. So by determining the logarithmic decrement from a graph of the output of an undamped seis, the actual open-circuit damping can be determined. h = d/sqrt(pi^2 + d^2) OR h =1/sqrt((pi/d)^2 +1) From this the actual undamped natural period wn can be found, since: wn = wd/sqrt(1-h^2), where wd is measured from a graphic output or by timing swings of the pendulum with a stopwatch. With no damping wn = wd; damping decreases the frequency of oscillation. In practice, the open-circuit damping of larger seismometers is generally small, like 0.1 to 0.3. It is due to the piston effect of the coils moving in the magnet gap, where clearances are significant to allow for mechanical variations of the coil position. If h or lambda = 0.3, wn = 1.05*wd, So a 1 hz seis will be measured as 0.95 hz with ho = 0.3. or considering the period T = 2*pi/w, Tn = Td*sqrt(1-h^2). Tn = 0.954*Td, (h = 0.3) So if the damped period is measured at 15 seconds with a stopwatch, the actual period is 14.31 seconds. If h = 0.1, Tn = 0.995*Td, or 15 sec Td is a Tn of 14.93, which is within the accuracy of the measurement. Damping lengthens the effective period. At h = 1, or critical damping, Td is infinite since there is no oscillation. A common application of using the logarithmic decrement to determine the damping (h or l or lambda or B (beta):) if the damping is changed by adding different parallel resistances to damp the coil, the successive overshoot ratios and hence the log decrement will change; the total damping Bt can be determined for each resistance and the motor constant G can be determined. G = sqrt(2*wn*m*(Rd + Rs)*(Bt - Bo)*10^-7) volts/cm/second. where Rd is the test resistance resulting in the new Bt (total damping), Rs is the coil resistance, and Bo is the open circuit damping. m is in grams, wn = 2*pi*fn. This is measured for several values of Rd that still allow the undamped oscillation to be measured to determine the logarithmic decrement and hence B. Then the desired damping resistor is calculated by: Bem = Bt - Bo, and usually a total damping of 1/2*sqrt(2) ( = 0.707) to 1 is desired). Bem = G^2 / (2*omega*M*(Rs + Rd), or Rd = [G^2 / (Bem*2*omega*m)] - Rs Where Bem is the electromagnetic damping, G is the main coil constant, omega is the angular frequency, equivalent to 2*pi/Tn, where Tn is the natural period, and M is the mass. For an L4-C, with a 5500 ohm coil, with G = 270 V/m/sec, Bo = 0.27, we want Bt to be 0.77, so Bem = 0.5, M = 1 kgm, omega = 2*pi, we calculate a damping resistor Rd of 6102 ohms for critical damping (0.7). For an S5000 Long Period Seis, with a 500 ohm coil, G = 100 V/m/sec, Bo = 0.1, we want a flatter response with Bt = 1, so Bem = 0.9, omega = 2*pi/15 (seconds), M = 11 kg, we calculate a resistor of 705 ohms for Bt = 1 (the LP is over damped for a broader response). Other topics like determining the static magnification (the sensitivity to a DC or zero-frequency signal) are really not applicable to modern electronic seismic recording. The method can be used to determine the sensitivity of a displacement transducer in a VBB instrument if a suitable micrometer is not available. SOOOOOO........ How do I calibrate a seismometer???????. ............... see my next email ........ Regards, Sean-Thomas References: ......... Benioff,H., "Earthquake Seismographs and Associated Instruments", Advances in Geophysics, vol 2, 1955, p219-275. Bullen K.E., "An Introduction to the Theory of Seismology", Cambridge University Press, London, 1965 (365 page book) Eaton,J, Theory of the Electromagnetic Seismograph, BSSA (Bulletin of the Seismological Society of America),#47, p37-76, 1957 Kisslinger, C., "Lecture Notes on Seismological Instrumentation", UNESCO and IISEE, International Institute of Seismology and Earthquake Engineering, Tokyo, Japan, 1967. Scherbaum, Frank, "Of Poles and Zeros: Fundamentals of Digital Seismology", Kluwer Academic Press, Dordrecht, Netherlands; 1996, ISBN 0-7923-4012-4 _____________________ _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Need help with SDR From: Nick & Sophie Caporossi nickcap@............. Date: Fri, 27 Aug 1999 22:37:01 -0400 Hi Larry and all. I transferred sdr to an other computer. The problem is: When I'm in SDR, using the "cntl and D" keys it does not put me into the temporary DOS mode. The "cntl and D" key flash momentarily and do nothing else. Am at a loss to know how to view a Replay file, to view in Winquake with out exiting Sdr. The new machine is 486 dx2x80 with 278meg hard drive 36meg Ram with a 7.0 Dos installed. I installed sdr22 and then updating with sdr262. It still did not operate correctly. I don't have this problem with an of my other computers. Any help will be greatly appreciated. Thanks Nick _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: STM-8 SETTINGS From: RADIOTEL@....... Date: Sat, 28 Aug 1999 00:28:37 EDT SEAN-THOMAS As I shared with you previously, I have my velocity model ( coil and magnet ) STM-8 seismo working. However, I have tried many combinations of weights and distance from the hinges to the flexture bars - but my best period thus far is about 4.5 sec. I presently have the distances from the hinges to the top and bottom flextures as reflected in your drawings. Any suggestions to assist me obtaining an eight second period or longer would be appreciated. Jim Allen Cerritos, CA _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Need help with SDR From: barry lotz gbl@....... Date: Fri, 27 Aug 1999 21:50:46 -0700 Hi I'm having the same problem. I think it may have something to do with available memory but am not sure. Barry Nick & Sophie Caporossi wrote: > Hi Larry and all. > I transferred sdr to an other computer. > The problem is: When I'm in SDR, using the "cntl and D" keys it does not > put me into the temporary DOS mode. The "cntl and D" key flash momentarily > and do nothing else. > > Am at a loss to know how to view a Replay file, to view in Winquake with > out exiting Sdr. > > The new machine is 486 dx2x80 with 278meg hard drive 36meg Ram with a 7.0 > Dos installed. I installed sdr22 and then updating with sdr262. It still > did not operate correctly. I don't have this problem with an of my other > computers. > Any help will be greatly appreciated. > > Thanks > > Nick > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: STM-8 SETTINGS From: S-T Morrissey sean@........... Date: Sat, 28 Aug 1999 00:03:06 -0500 (CDT) Jim, I can only guess that the total spring constant of the spring, its flexures, and the main hinges is too large. I am presently using hinges that are 0.005" thick and 3/8 inch wide. The free, non-contacting area where the hinges cross to the frame angles is about 1/16". As I move the upper contact point of the main leaf spring along the boom closer to the hinges, adjusting the mass position accordingly, I can reach a point of infinite period or instability. The range of adjustment (moving along the boom) from several seconds to over ten seconds is only about 1 cm. Also, the level of the boom affects the period. As the instrument is tilted back, raising the mass end of the boom, the period lengthens. This is reducing the gravity vector and direction of the forces at the hinge. Obviously, tilt it too far, and it will flop over. Hope this helps. Maybe someone else has some suggestion. Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Edward Cranswick in Turkey From: meredith lamb psnseismograph52@.......... Date: Fri, 27 Aug 1999 23:09:52 +0000 Hi, Anybody heard from Edward Cranswick in Turkey yet? He left last Friday....just wondering.... Probably incredibly busy I imagine. Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Need help with SDR From: Larry Cochrane cochrane@.............. Date: Sat, 28 Aug 1999 01:01:36 -0700 Nick, The problem, as Barry pointed out, is with the amount of memory available to run another copy of DOS. The first thing to try is running memmaker at the DOS prompt. This may free up enough memory. This utility, available in higher version of DOS and Win95/98, moves some of the drivers, and the first copy of DOS, into memory above 640K. This frees up memory below 640k to run another copy of DOS. Also, make sure you have selected the same sample rate and number of channel to records. Increasing either will use more memory. -Larry Cochrane Redwood City, PSN At 10:37 PM 8/27/99 -0400, Nick & Sophie Caporossi wrote: >Hi Larry and all. > I transferred sdr to an other computer. >The problem is: When I'm in SDR, using the "cntl and D" keys it does not >put me into the temporary DOS mode. The "cntl and D" key flash momentarily >and do nothing else. > >Am at a loss to know how to view a Replay file, to view in Winquake with >out exiting Sdr. > >The new machine is 486 dx2x80 with 278meg hard drive 36meg Ram with a 7.0 >Dos installed. I installed sdr22 and then updating with sdr262. It still >did not operate correctly. I don't have this problem with an of my other >computers. > Any help will be greatly appreciated. > >Thanks > >Nick > >_____________________________________________________________________ > >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) Subject: Re: Hypoellipse From: Arie Verveer ajbv@............ Date: Sat, 28 Aug 1999 21:36:34 +0800 Hi Francesco, Please take note that I'm just a novice in using Hypoellipse. So my description on the way the program is used may be questionable. Anyhow, here goes. It should be noted the file names can be different from the one's used here. (I'll call them the same as the manual file names.) 1) The first thing is to copy all the "DOS" and "Documents" files form Dr. John Lahr's great site. http://lahr.org/iaspei/northam/ak/s_ak/programs/hypoel/hypoel.html Its best to place each individual section in a separate folder. Its important for this example to copy all the "Quickrun" files to a new "quickrun folder". Make a backup of this folder. 2) Print out the Quick-Start manual. 3) (Read chapter on "crustal.prm" ) In the "Quickrun folder" load the file called "crustal.prm" into a text editor. You need to modify this "VELOCITY" file for your location. I'll give you the data I have used but you will need to talk to Dr. Lahr or you local Geophysical Observatory and get the velocity of the "P" and "S" waves at various depths around you location. In My area its 6.13 Km/sec for a P wave at 0 Km Depth. 7.14 Km/sec for a P wave at 19 km Depth 8.27 Km/sec for a P wave at 36.0 km Depth In My area its 3.62 Km/sec for a S wave at 0 Km Depth. 3.96 Km/sec for a S wave at 19 km Depth 4.75 Km/sec for a S wave at 36.0 km Depth Now calculate the (Vp/Vs) data for each depth. 0 Km Depth is (6.13/3.62) = 1.69 19 Km Depth is (7.14/3.96) = 1.80 36 Km Depth is (8.27/4.75) = 1.74 Your model may have different depths but the principle is the same. Using the information from the "quickrun" manual modify the opened file "crustal.prm" to reflect the velocity model data. Note the column spacing. It Should look someting like this for my area. ! Model 1: Western Australia ! VELOCITY 6.13 0.0 1.69 VELOCITY 7.14 19.0 1.80 VELOCITY 8.27 36.0 1.74 Close and save the file. 4) Input Data. Its important to follow the manual and watch your column spacing. For each seismic station you should calculate, using "Winquake" an arrival time of the "P" wave or the "S" wave or both waves. Accuracy, depends on how good your data is and how many stations you have. Not less than three stations. I used my station plus two AutoDrm stations. BICK station P arrival is 1:46:38.5 On 99/07/13 S arrival 1:46:56.6 FORT station P arrival is 1:48:22.4 On 99/07/13 S arrival 1:49:59.5 - Very Poor data MEEK station P arrival is 1:47:22.9 On 99/07/13 S arrival 1:48:14.8 I also calculated the amplitude of the wave data, but its not used in this example. Magnitude is a bigger problem and wont be considered in this example. "Winquake" gives a very good estimate on the magnitude when the right corrections are entered. Amplitude BICK 5660 FORT 376 MEEK 1319 In the "Quickrun folder" load the file called "akutan.pha" into a text editor. You need to modify this file for your Input Data. Again I'll give you the data from my station plus the two AutoDrm stations. Armed with the arrival time data and your "quickrun" manual; the modified "akutan.pha" file should look something like this. BICKIP 9907130146 3850 5660 4121 FORTEP 9907130148 2240 11950 376 MEEKEP 9907130147 2290 7480 1319 C* YrMoDyHrMn P-Sec S-Sec Amp C*(F) 960423065129i. C*(C) Any record starting with C* is a comment. Make sure the columns are correct. The printout here may not reflect the correct column spacing. Close and save the file. You have now set the velocity Model and input data for a particular quake. 5) Station Locations. In the "Quickrun folder" load the file called "akutan.sta" into a text editor. You need to modify this file for your station Input Data. Again I'll give you the data from my station plus the two AutoDrm stations. BICK -32.008 Latitude by 116.135E Longitude 300 Meteres above Mean sea level. FORT -30.778 by 128.059E 165 MEEK -26.638 by 118.615E 530 So BICK is -32 degrees 00.48 minutes south by 114 degees 08.10 minutes east FORT -30 46.68 128 03.54 MEEK -26 38.28 118 36.90 Armed with the station location's and your "quickrun" manual. The "akutan.sta" file should look something like this. BICK32S00.48 116E08.10 300 BICK* 18 FORT30S46.68 128E03.54 165 FORT* 18 MEEK26S38.28 118E36.90 530 MEEK* 18 Save and close the file. 6) Seismograph amplitude response. I entered this data since I had it available, its need for magnitude calculation. I'm going to do this later. In the "Quickrun folder" load the file called "caldata.prm" into a text editor. You need to modify this file for your seismograph amplitude response. Again I'll give you the data from my station plus the two AutoDrm stations. The file should look like this. Check the manual for column layout. BICK D 980713 999999 1 1.00 400000. FORT D 980713 999999 1 1.00 591716. MEEK D 980713 999999 1 1.00 680272. Save and close the file. 7) Options. Hypoellipse allows many, many options is the way it process data. I changed these parameters so it approached the reduction in the way I like it to. You will need to printout the full manual to see the options. See page 2-23 "Big manual". Maybe for this exercise just print out the relevant part of the manual. (2-23 -> 2.29) In the "Quickrun folder" load the file called "headopts.vol" into a text editor. You need to modify this file for your various options. In this case I'll give my selection and why. I'm a novice in all of this so shot me down, with compassion. Options and Why ! Options - control file header content Bickley Western Australia ! Run Name reset test 1 1.69 !Ratio P/S wave velocity ** reset test 2 6.13 !P wave velocity ** reset test 3 -31.0 !First Trial Latitude ** reset test 4 -117.0 !First Trial Longitude ** reset test 5 -1.0 !First trial depth reset test 6 -1.0 !RMS See page 2-24 reset test 8 0.0 !Top of Model, respect to sea level ** reset test 21 20. !Maximum nuber of iteration allowed (important) reset test 22 1.0 !Limit chang of focal depth (km) ** reset test 31 -0.87 !C1 constant (magnitude) ** reset test 32 2.0 !C2 constant (magnitude) ** reset test 33 0.0035!C3 constant (magnitude) ** ! end of headopts.vol NOTE: the Lines ending with "**" aren't really needed in this epicentre location example. Anyhow the new "headopts.vol" should look like this. ! Options - control file header content Bickley Western Australia reset test 1 1.69 reset test 2 6.13 reset test 3 -31.0 reset test 4 -117.0 reset test 5 -1.0 reset test 6 -1.0 reset test 8 0.0 reset test 21 20. reset test 22 1.0 reset test 31 -0.87 reset test 32 2.0 reset test 33 0.0035 ! end of headopts.vol Save and close the file. 8) Input control file. (Hypo.ctl) This file controls which files are used and controls. In the "Quickrun folder" load the file called "hypo.ctl" into a text editor. You need to modify this file for your file name and options. (Example) It should look something like this. ! headopts.vol contain the setup parameters ! for running HYPOELLIPSE. jump headopts.vol ! ! crustal.prm specifies the velocity model. jump crustal.prm ! ! caldata.prm contains the calibration parameters. uofacal option caldata.prm ! ! Constants noprint = 1 will cause documentation of the ! parameter values, crustal model, station locations, etc ! to be added to the output (.out) file. Note that if the ! same parameter value it specified more than once, the last ! setting will be the one used (in this case the value will ! be set to 1). constants noprint 0 constants noprint 1 ! ! Printer option 1 adds a blow by blow description of ! every iteration step and is useful for debugging purposes. ! Reverse the order of the following records to turn this ! option on. printer option 1 printer option 0 tabulation option 4 ! begin station list +1 19960101 jump akutan.sta arrival times next jump akutan.pha Save and close the file. You will need to consult the "Big Manual" for a full explenation of this file. -------------------------------------------- The files (akutan.sta, crustal.prm, caldata.prm, and headopt.vol ) once set shouldn't need to be changed for other events. 9) Copy the file "Hypoel.ex" into your quickrun folder and rename it "Hypoel.exe". At this point I recommend to close all other windows except the "quickrun" folder. 10) Lets give it a go!! Open an "Msdos" Window. I recommend a window and not the full screen. See "MsDos" prompt, properties. In the "MsDos" window change the directory until you are in the "quickrun" folder. At the prompt, type. hypoel < hypo.in (and hit the return key) If all goes well you should see some new files in the "quickrun" folder. Look at the "Hypoel.out" file with a text editor and see the program process and reduction. Hopefully you should see the quakes location at 99/07/13 01:46:13.6 UT -31.21 latitude (-31 degrees 12.6 minutes) 117.48 East (117 degrees 28.8 minutes) 3 km Depth. Or something close to this "A" accuracy position. More data means more accuracy! If you want to re-compute this run with some modifications then you will need to delete the previously generated output files. Go to the "MsDos" window and repeat the line hypoel < hypo.in (and hit the return key) Francesco, I hope this is of help and I'll send you these files in a "ZIP". Again I wish to thank Dr. John Lahr for this great resource. Have Fun. I did. Arie _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Hypoellipse From: The Lahrs JohnJan@........ Date: Sat, 28 Aug 1999 08:17:47 -0600 Hi Arie, Wow, what a great tutorial for running Hypoellipse! Would you mind if I include this along with the program on the web site? I will give it the title: Short tutorial written by Arie Verveer on running Hypoellipse on a PC for the first time. Thanks! John At 09:36 PM 8/28/99 +0800, you wrote: >Hi Francesco, > >Please take note that I'm just a novice in using Hypoellipse. So my >description ...... * John C. and Jan H. Lahr * * JohnJan@........ * * 1925 Foothills Road * * Golden, Colorado 80401-1718 * * (303) 215-9913 * * http://lahr.org/john-jan * * http://giseis.alaska.edu/lahr * _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Edward Cranswick in Turkey From: Mustafa Erdik earthquake@............... Date: Sat, 28 Aug 1999 17:48:14 +0100 Hi, Ed is working in the field with us. He is fine and healthy. Regards, Mustafa Erdik At 11:09 PM 8/27/99 +0000, you wrote: >Hi, > >Anybody heard from Edward Cranswick in Turkey yet? He >left last Friday....just wondering.... Probably incredibly busy >I imagine. > >Meredith Lamb > > > > >_____________________________________________________________________ > >Public Seismic Network Mailing List (PSN-L) > >To leave this list email listserver@.............. with the body of the >message: leave PSN-L > Mustafa Erdik Professor and Chair, Department of Earthquake Engineering Kandilli Observatory and Earthquake Engineering, Bogazici University 81220 Cengelkoy, Istanbul, Turkey e-mail: erdik@............ earthquake@............... Web: http://www.koeri.boun.edu.tr/earthqk/earthqk.html Fax: +90.216.308.0163, +90.216.332.1711 Tel: (Bus.) +90.216.332.6560, +90.216.332.9701; (Home) +90.216.339.8633 _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Need help with SDR, thanks From: Nick & Sophie Caporossi nickcap@............. Date: Sun, 29 Aug 1999 00:07:35 -0400 Thanks Barry and Larry: The second hand computers I got from a computer show has most of the memory un enabled. Getting to the setup was quite a task. It was protected by a password. Had to take the computers apart and hunt around for the jumper straps to bypass the password. Should be home free now. I may remove command file and install Windows95 and take it from there. Thanks for the tip. Nick At 01:01 AM 8/28/99 -0700, you wrote: >Nick, > >The problem, as Barry pointed out, is with the amount of memory available >to run another copy of DOS. The first thing to try is running memmaker at >the DOS prompt. This may free up enough memory. This utility, available in >higher version of DOS and Win95/98, moves some of the drivers, and the >first copy of DOS, into memory above 640K. This frees up memory below 640k >to run another copy of DOS. > >Also, make sure you have selected the same sample rate and number of >channel to records. Increasing either will use more memory. > >-Larry Cochrane >Redwood City, PSN _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: [Fwd: calibration: log decrement] From: "Rex Klopfenstein, Jr." rklopfen@......... Date: Sun, 29 Aug 1999 15:00:18 -0400 Thanks for the info. Will take sometime to ingest and some trips to the library. By the way, the references really helps!!! > Rex, > > Regarding your notes on calibrating yout SG sensors.... > -- Rex Klopfenstein, Jr. Bowling Green, OH rklopfen@......... http://www.wcnet.org/~rklopfen _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: USGS 150th Anniversary open house photos From: meredith lamb psnseismograph52@.......... Date: Sun, 29 Aug 1999 14:03:17 +0000 Hi everyone, Now have on a website some 86 photos on 15 pages of the 150th anniversary open house exhibits shown at the NEIC in Golden Colorado, and the Federal Center in Lakewood, Colorado on August 28th 1999. I would say it seemed to be a huge success, what with perhaps thousands of people visiting both places. The USGS really put up a large number of exhibits and went all out on a large number of subjects they are involved with. http://members.xoom.com/seismogram/page32.html .....will get you started. Xoom seems to occasionally drop pictures and initially somewhat slow loading; you may have to reload sometimes to see them all. This is a what you see is what you get Netscape Composer program, so, the html, may not function perfectly. ......................... Note....I'll be switching USWest addresses soon, so, the Xoom site will be the primary for me for some time: http://members.xoom.com/seismogram/ Enjoy the pictures....it was alot of fun at the open house. Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Murphys law....USGS site photos? From: meredith lamb psnseismograph52@.......... Date: Sun, 29 Aug 1999 18:01:08 +0000 Hi all, Yes...I do note the Xoom site seems to be down. The general notes indicates a number of servers are not working right at this time. Overall, this doesn't seem to be unusual per my experience with Xoom.com. Suggest you try sometime in the future again. Its a free web site, and has some 7 million members, so problems aren't too scarce...ha. It seemed to have gone down about 10 minutes after the first email notice of the USGS photos....murphys law prevails.... Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Murphys law....USGS site photos? From: Raul Alvarez ralvarez@........ Date: Sun, 29 Aug 1999 18:13:22 -0600 Meredith, When I try to go to your site, I get the following message: "Forbidden You don't have permission to access /s/e/seismogram/ on this server." Raul meredith lamb wrote: > Hi all, > > Yes...I do note the Xoom site seems to be down. The general > notes indicates a number of servers are not working right at > this time. Overall, this doesn't seem to be unusual per my > experience with Xoom.com. Suggest you try sometime in the > future again. Its a free web site, and has some 7 million members, > so problems aren't too scarce...ha. > > It seemed to have gone down about 10 minutes after the first > email notice of the USGS photos....murphys law prevails.... > > Meredith Lamb > > _____________________________________________________________________ > > 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) Subject: Re: Murphys law....USGS site photos? From: Larry Cochrane cochrane@.............. Date: Sun, 29 Aug 1999 22:00:05 -0700 Hmmm the phrase "you get what you pay for" comes to mind.... -Larry At 06:01 PM 8/29/99 +0000, you wrote: >Hi all, > >Yes...I do note the Xoom site seems to be down. The general >notes indicates a number of servers are not working right at >this time. Overall, this doesn't seem to be unusual per my >experience with Xoom.com. Suggest you try sometime in the >future again. Its a free web site, and has some 7 million members, >so problems aren't too scarce...ha. > >It seemed to have gone down about 10 minutes after the first >email notice of the USGS photos....murphys law prevails.... > >Meredith Lamb > > > > > >_____________________________________________________________________ > >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) Subject: PSN - Increase in noise From: "Rex Klopfenstein, Jr" rklopfen@......... Date: Mon, 30 Aug 1999 13:43:42 -0400 I have two S-G seisms running and everything was fine. I had the amplifiers adjusted to display about +/-100 counts of background noise. Sunday (8/29/99) I turned on the monitor on my SDR computer. All channels (HI/LO on both N/S and E/W) are somewhat more noisy. The average values are now about +/-300 to 400 counts. I retrieved a block of data from my N/S channel during a quiet time (2:00am LOCAL). I then switched to the FFT screen and noted a peak at 0.12 on LOG(f) scale (x axis). I assume that the scale is log base 10 of frequency or 0.12 = approx 1.3 Hz?? Would this increase in noise be caused by the hurricane on the East Coast (I am located in NW Ohio). I remember seeing something on this list sometime ago, but can't remember if there was a characteristic frequency of this hurricane noise. If the hurricane isn't doing it, it's time for some detective work!! Any help would appreciated before I start looking for gremlins!!! -- Rex Klopfentein, Jr. rklopfen@......... http://www.wcnet.org/~rklopfen _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: PSN - Increase in noise From: "Kevin Mackey" mackeyke@............. Date: Tue, 31 Aug 1999 14:41:55 -0400 Rex, I suspect that the hurricane might be your problem. I am located in East Lansing, MI - operating station LNSM (not a PSN station). We currently are seeing noise levels approximately 10X normal background in the 0.2 Hz range. This is normal for us whenever there is a hurricane or large storm off the east coast. At times, the noise here has increased about 50X due to hurricanes. So, I would suggest waiting until the hurricane passes and see if your noise levels go down. If anyone has any references for coastal storm induced noise for stations far inland, it might be helpful for additional information. Kevin Mackey Michigan State University ----- Original Message ----- From: Rex Klopfenstein, Jr To: Sent: Monday, August 30, 1999 1:43 PM Subject: PSN - Increase in noise > I have two S-G seisms running and everything was fine. I had the > amplifiers adjusted to display about +/-100 counts of background noise. > Sunday (8/29/99) I turned on the monitor on my SDR computer. All > channels (HI/LO on both N/S and E/W) are somewhat more noisy. The > average values are now about +/-300 to 400 counts. > > Would this increase in noise be caused by the hurricane on the East > Coast (I am located in NW Ohio). I remember seeing something on this > list sometime ago, but can't remember if there was a characteristic > frequency of this hurricane noise. > > If the hurricane isn't doing it, it's time for some detective work!! > > Rex Klopfentein, Jr. > rklopfen@......... > http://www.wcnet.org/~rklopfen > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: PSN - Increase in noise From: meredith lamb psnseismograph52@.......... Date: Mon, 30 Aug 1999 12:49:59 +0000 "Rex Klopfenstein, Jr" wrote: > I have two S-G seisms running and everything was fine. I had the > amplifiers adjusted to display about +/-100 counts of background noise. > Sunday (8/29/99) I turned on the monitor on my SDR computer. All > channels (HI/LO on both N/S and E/W) are somewhat more noisy. The > average values are now about +/-300 to 400 counts. > > I retrieved a block of data from my N/S channel during a quiet time > (2:00am LOCAL). I then switched to the FFT screen and noted a peak at > 0.12 on LOG(f) scale (x axis). I assume that the scale is log base 10 > of frequency or 0.12 = approx 1.3 Hz?? > > Would this increase in noise be caused by the hurricane on the East > Coast (I am located in NW Ohio). I remember seeing something on this > list sometime ago, but can't remember if there was a characteristic > frequency of this hurricane noise. > > If the hurricane isn't doing it, it's time for some detective work!! > > Any help would appreciated before I start looking for gremlins!!! > -- > Rex Klopfentein, Jr. > rklopfen@......... > http://www.wcnet.org/~rklopfen > Rex, Don't think anything is unusual on your end....the hurricane microseisms are hitting me hard here too. Need to increase the trigger level here...probably as well there...its set it off afew times since yesterday when it started building up with time. Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Microseisms from hurricane Dennis From: RLLaney@....... Date: Mon, 30 Aug 1999 18:16:27 EDT For the past 2 days, I have been observing microseisms gradually increasing in amplitude as hurricane Dennis moves northward along the Atlantic coast. Periods are in the 4 to 6 second range. The amplitude was so great this morning that I had to increase the alarm threshold to keep from recording unwanted files. I would be interested in hearing from others who are, or who are not, receiving these microseisms and how far westward they can be detected. Thanks. Bob Laney Herndon, VA _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Microseisms from hurricane Dennis From: twleiper@........ Date: Mon, 30 Aug 1999 19:10:01 -0400 Our background level here in Stamford CT is running about 40X normal thanks to Dennis the Menace. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: PSN - Increase in noise From: "Rex Klopfenstein, Jr" rklopfen@......... Date: Mon, 30 Aug 1999 21:16:56 -0400 If I would have looked at WinQuake closer I would have seen that the scale is in frequency just scaled to LOG!!! Therefore I am seeing about 0.12 Hz noise peak. "Rex Klopfenstein, Jr" wrote: > ... I then switched to the FFT screen and noted a peak at > 0.12 on LOG(f) scale (x axis). I assume that the scale is log base 10 > of frequency or 0.12 = approx 1.3 Hz?? > -- Rex Klopfentein, Jr. rklopfen@......... http://www.wcnet.org/~rklopfen _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Autodrm calibration From: barry lotz gbl@....... Date: Mon, 30 Aug 1999 19:29:33 -0700 Just a thought-- Autodrm stations have calibration info included with the files requested (eg 0.12 nm/count). If I choose a station near mine and record an event in the same direction (ie N,E or Z) then could I compare my station response both in frequency and amplitude? I realize local effects would have an effect on results. For example, if the event is of similar distance from me as an autodrm station with gain of 0.2 nm/count, if my amplitude is higher, would it indicate my gain is also higher? (possibly in a linear fashion?) Barry _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Microseisms from hurricane Dennis From: Larry Cochrane cochrane@.............. Date: Mon, 30 Aug 1999 20:16:59 -0700 At 06:16 PM 8/30/99 EDT, you wrote: >For the past 2 days, I have been observing microseisms gradually increasing >in amplitude as hurricane Dennis moves northward along the Atlantic coast. >Periods are in the 4 to 6 second range. The amplitude was so great this >morning that I had to increase the alarm threshold to keep from recording >unwanted files. > >I would be interested in hearing from others who are, or who are not, >receiving these microseisms and how far westward they can be detected. The microseismic activity has not increased here... -Larry Cochrane Redwood City, PSN _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: 6-second microseisms From: S-T Morrissey sean@........... Date: Mon, 30 Aug 1999 23:57:18 -0500 (CDT) Re microseisms from hurricane Dennis: Here at St. Louis the level of the 6-second microseisms as recorded from the STM8 broadband in the basement had increased by a factor of 10 over the previous week. THe peak level from the VBB was about 20 millivolts. With a broadband sensitivity of 5.29 mv/micron/second, this indicates a peak velocity of 3.4 microns/second. At a period T of 6 seconds, the angular frequency is w =2*pi/T, or 1.05*sec^-1. The velocity is divided by w to give a peak displacement of 3.6 microns. Here are some notes I have previously posted: Re: 6-second microseisms and hurricanes: An interesting phenomenon in the eastern USA is that when a large wind storm due to a deep barometric low occurs off the east coast, particularly off of New England, the wave energy pounding on the continental shelf propagates through the lithosphere under the eastern USA as a 6-second surface wave, at about half the period of the oceanic wave. This is also true of any storm off the east coast, except that the period will be different, varying from 4 to 10 seconds. Storms off the southwest coast cause a longer storm wave, but the predominant energy is still from 5 to 8 seconds. This storm microseism noise is the major reason that the original global seismograph stations were configured as two separate instruments: a SP or short-period, peaking in gain at about 1 second, at 50k to 100k, and the LP, or long-period, peaking at 15 to 30 seconds, with magnifications from 1.5k to 6k. During a microseism storm, even the LP record could be a scribbled mess; usually the storm peak would only last for a several hours, so we wouldn't interrupt the recording. With the advent of wide dynamic range digital recording and VBB response instruments, we deal with the microseisms in later digital processing. However, for a visible monitor record on a drum recorder, we usually use a "twin-T" notch filter to reduce the microseisms by 40db (1/100). The twin-T is passive and easy to make with 3 resistors and 4 capacitors. Even with the filter, a strong storm can fill the record with noise, which is easily seen as 10 waves per minute. A historical note on tracking hurricanes before the use of satellites and aircraft: small seismograph arrays were used. At our old station FLO outside St. Louis, two additional small vaults were built 1/4 mile west and north of the main vault. THen intermediate period (10 second) seismometers were used, connected to 6-second galvanometers for photo recording with a peak response at 6-seconds. THe relative phase of the microseisms crossing the L shaped array provided a vector pointing toward the origin if the waves. It was much more accurate than 3-component particle motion analysis. With several such stations (one was at Spring Hill, AL, another at Rochester, NY) providing a pointer, the location of the hurricane could be estimated, even when hundreds of km from shore. There are some examples of the spectral noise from microseisms on my web page featuring figures and data; there is even an example of a storm peak from a hurricane last year. http://www.eas.slu.edu/People/STMorrissey/index.html Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Automatic E-mailed earthquake files. From: Arie Verveer ajbv@............ Date: Tue, 31 Aug 1999 14:08:20 +0800 Hi Lately I've been working on a way to send the "SDR" quake files automatically via email. The reason is, my station is located in a basement some 11 km from home and that meant a weekend trip to "SDR" to retrieve the data. Anyhow the following method has been developed to "check and send" any new "SDR" quake files on the hour, to an e-mail address. 1) You need a "SDR" logging computer networked to a another computer. That computer has to be connected to a "ISP" via a modem or some other network connection. 2) Set-up "SDR" to save the event files to the networked computer as per "Winquake" instructions. On the network computer I installed some server software for "windows" called "Sambar 4.2.9" It runs in the background and is so easy to install. There is a charge to get the professional version. (professional - mail, ftp, tenet ) servers. The rest is easy; set-up the server scheduler to run a "CGI" on the hour. This "CGI" is essentially a small program that checks the "SDR" files and looks for a new entry. If data is found, it's e-mailed via a server program called "mailit.exe". This a "DOS" program that can send email. This "mailit.exe" program sends the e-mail to the server mailing program and that in turn sends it to e-mail address. It's done this way so you could "forward" the mail to other interested people. I have a permanent "mail" connection to the internet world via the networked computer. But the server software allows for "Dial-On-Demand". You must have some familiarity with "TCP/IP" to get things going. If anyone's interested then I can send you the source "C" code for the "CGI". Its really simple.The code is first draft and can be improved. It should be remembered that the e-mailed data is "RAW" data and may only be a false trigger. Also I'm working on a variant of this "CGI" for quick notification. But that is very specific and involves another computer(?). Regards Arie ajbv@............ _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Microseisms from hurricane Dennis From: "Charlie Rond" rond@................ Date: Tue, 31 Aug 1999 01:34:45 -0500 Bob, >For the past 2 days, I have been observing microseisms gradually increasing >in amplitude as hurricane Dennis moves northward along the Atlantic coast. >Periods are in the 4 to 6 second range. The amplitude was so great this >morning that I had to increase the alarm threshold to keep from recording >unwanted files. > >I would be interested in hearing from others who are, or who are not, >receiving these microseisms and how far westward they can be detected. The same thing has been happening here in Memphis, TN. I was so fascinated watching them, I didn't think to change the threshold. This evening while I was gone, the program screeched to a halt as the hard drive filled up with "events"! They are the largest microseism I've ever recorded! _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: USGS open house photos...again... From: meredith lamb psnseismograph52@.......... Date: Tue, 31 Aug 1999 09:08:58 +0000 Hi all, Trying again..... I put the USGS open house photos on another web site. Hopefully it will work somewhat better, and faster. The Xoom com site seems to be getting worse with time, and patch attempts. http://www.geocities.com/ResearchTriangle/Facility/1739/page47.html Yahoo/Geocities has had its long period of troubles also, but seems to be somewhat better. You may need to reload sometimes. There is a pop up ad, but moving it somewhat out of the way initially, will prevent having to delete it with every page you see. Depending on your computer speed of loading, viewing all could consume quite some time. The site also contains all the rest of my original files: http://www.geocities.com/ResearchTriangle/Facility/1739/index.html Thanks, Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: 6-second microseisms From: "Mark & Lori" mlpg@................. Date: Tue, 31 Aug 1999 10:33:01 -0700 Can you please take me off your address list? Thank you ---------- >From: S-T Morrissey >To: psn-l@.............. >Subject: 6-second microseisms >Date: Mon, Aug 30, 1999, 9:57 PM > >Re microseisms from hurricane Dennis: > >Here at St. Louis the level of the 6-second microseisms as recorded >from the STM8 broadband in the basement had increased by a factor of 10 over >the previous week. THe peak level from the VBB was about 20 millivolts. >With a broadband sensitivity of 5.29 mv/micron/second, this indicates >a peak velocity of 3.4 microns/second. At a period T of 6 seconds, >the angular frequency is w =2*pi/T, or 1.05*sec^-1. The velocity is >divided by w to give a peak displacement of 3.6 microns. > >Here are some notes I have previously posted: > >Re: 6-second microseisms and hurricanes: > >An interesting phenomenon in the eastern USA is that when a large >wind storm due to a deep barometric low occurs off the east coast, >particularly off of New England, the wave energy pounding on the >continental shelf propagates through the lithosphere under the >eastern USA as a 6-second surface wave, at about half the period of >the oceanic wave. This is also true of any storm off the east >coast, except that the period will be different, varying from 4 to >10 seconds. Storms off the southwest coast cause a longer storm wave, >but the predominant energy is still from 5 to 8 seconds. > >This storm microseism noise is the major reason that the original >global seismograph stations were configured as two separate instruments: >a SP or short-period, peaking in gain at about 1 second, at 50k to 100k, >and the LP, or long-period, peaking at 15 to 30 seconds, with magnifications >from 1.5k to 6k. During a microseism storm, even the LP record could be >a scribbled mess; usually the storm peak would only last for a several >hours, so we wouldn't interrupt the recording. > >With the advent of wide dynamic range digital recording and VBB response >instruments, we deal with the microseisms in later digital processing. >However, for a visible monitor record on a drum recorder, we usually >use a "twin-T" notch filter to reduce the microseisms by 40db (1/100). >The twin-T is passive and easy to make with 3 resistors and 4 capacitors. >Even with the filter, a strong storm can fill the record with noise, which >is easily seen as 10 waves per minute. > >A historical note on tracking hurricanes before the use of >satellites and aircraft: small seismograph arrays were used. >At our old station FLO outside St. Louis, two additional small >vaults were built 1/4 mile west and north of the main vault. >THen intermediate period (10 second) seismometers were used, >connected to 6-second galvanometers for photo recording with a >peak response at 6-seconds. >THe relative phase of the microseisms crossing the L shaped >array provided a vector pointing toward the origin if the waves. >It was much more accurate than 3-component particle motion analysis. >With several such stations (one was at Spring Hill, AL, another at >Rochester, NY) providing a pointer, the location of the hurricane >could be estimated, even when hundreds of km from shore. > >There are some examples of the spectral noise from microseisms on >my web page featuring figures and data; there is even an example of >a storm peak from a hurricane last year. >http://www.eas.slu.edu/People/STMorrissey/index.html > >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 _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Automatic E-mailed earthquake files. From: "Mark & Lori" mlpg@................. Date: Tue, 31 Aug 1999 10:34:46 -0700 Can you please take me off you address list? Thank you. ---------- >From: Arie Verveer >To: PSN-L Mailing List >Subject: Automatic E-mailed earthquake files. >Date: Mon, Aug 30, 1999, 11:08 PM > >Hi > >Lately I've been working on a way to send the "SDR" quake files >automatically via email. >The reason is, my station is located in a basement some 11 km from home >and that meant >a weekend trip to "SDR" to retrieve the data. Anyhow the following >method has been >developed to "check and send" any new "SDR" quake files on the hour, to an e-mail >address. > >1) >You need a "SDR" logging computer networked to a another computer. That computer >has to be connected to a "ISP" via a modem or some other network connection. > >2) >Set-up "SDR" to save the event files to the networked computer as per "Winquake" >instructions. > >On the network computer I installed some server software for "windows" called >"Sambar 4.2.9" It runs in the background and is so easy to install. There is a >charge to get the professional version. (professional - mail, ftp, tenet ) >servers. > >The rest is easy; set-up the server scheduler to run a "CGI" on the hour. >This "CGI" >is essentially a small program that checks the "SDR" files and looks for a >new entry. >If data is found, it's e-mailed via a server program called "mailit.exe". > >This a "DOS" program that can send email. This "mailit.exe" program sends >the e-mail >to the server mailing program and that in turn sends it to e-mail address. >It's done this way >so you could "forward" the mail to other interested people. > >I have a permanent "mail" connection to the internet world via the >networked computer. >But the server software allows for "Dial-On-Demand". > >You must have some familiarity with "TCP/IP" to get things going. If >anyone's interested then >I can send you the source "C" code for the "CGI". Its really simple.The >code is first draft and > >can be improved. > >It should be remembered that the e-mailed data is "RAW" data and may only >be a false trigger. >Also I'm working on a variant of this "CGI" for quick notification. But >that is very specific >and >involves another computer(?). > > >Regards > >Arie > >ajbv@............ > > >_____________________________________________________________________ > >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) Subject: Re: USGS open house photos...again... From: "Mark & Lori" mlpg@................. Date: Tue, 31 Aug 1999 10:37:23 -0700 Can you please take me off your address list? Thank You ---------- >From: meredith lamb >To: psn-L mailing list >Subject: USGS open house photos...again... >Date: Tue, Aug 31, 1999, 2:08 AM > >Hi all, > >Trying again..... I put the USGS open house photos on another >web site. Hopefully it will work somewhat better, and faster. >The Xoom com site seems to be getting worse with time, and >patch attempts. > >http://www.geocities.com/ResearchTriangle/Facility/1739/page47.html > >Yahoo/Geocities has had its long period of troubles also, but seems >to be somewhat better. You may need to reload sometimes. >There is a pop up ad, but moving it somewhat out of the way >initially, will prevent having to delete it with every page you see. > >Depending on your computer speed of loading, viewing all could >consume quite some time. > >The site also contains all the rest of my original files: > >http://www.geocities.com/ResearchTriangle/Facility/1739/index.html > >Thanks, > >Meredith Lamb > > > > >_____________________________________________________________________ > >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) Subject: Re: USGS open house photos...again... From: Greg ghost@............. Date: Tue, 31 Aug 1999 11:29:00 -0700 meredith lamb wrote: > Trying again..... I put the USGS open house photos on another > web site. Hopefully it will work somewhat better, and faster. > http://www.geocities.com/ResearchTriangle/Facility/1739/page47.html Thanks Meredith for taking and posting those photos. ,Greg _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: [Fwd: Update?] From: Edward Cranswick cranswick@........ Date: Sat, 04 Sep 1999 01:32:00 -0600 -- Edward Cranswick US Geological Survey Golden, CO 80401 USA TEL: 303-273-8609 FAX: 303-273-8600 -------------------------------------------------------------- Kocaeli Earthquake Kandilli Observatory Istanbul, Turkey Tom- The website has been updated and provides a summary of our activities in Turkey. Please forward this message to the appropriate recipients. We leave for Golden tomorrow. Thank you for coordinating our activities here in Turkey. -Edward Tom Holzer wrote: > Dave and Ed, > > I am curious about how the deployment is going. Did Dave get the > Toyota-plant K2 on line in time for the M5.2 aftershock? Did all of our > instruments record it? Did any of you feel it? > > What is the present stage of the USGS/Kandilli deployment? Have the > additional instruments been redeployed and and the origninal deployment > reconfigured? Has Kandilli been recording on the SSA-2's? > > We had an easy, but long trip home. We have been besieged by Bay area > press, but the earthquake stories are fading from the national press. > > I want to say again what a pleasure it was working with you guys. I was > really impressed by your operation. I think the Survey brass was really > impressed by the way the whole group performed. I have gotten nothing but > positive vibes. It made me proud to be part of the effort. > > Have a safe trip home in case we do not communicate again. > > Tom > > -----/\/\/\/\/\/\/\/\/\/\/\/\/\/----------- > > Thomas L. Holzer > U. S. Geological Survey > 345 Middlefield Road, MS 977 > Menlo Park, CA 94025-3591 USA > Voice: 650-329-5637 FAX: 650-329-5163 > E-mail: tholzer@........ -- Edward Cranswick US Geological Survey Golden, CO 80401 USA TEL: 303-273-8609 FAX: 303-273-8600 -------------------------------------------------------------- Kocaeli Earthquake Kandilli Observatory Istanbul, Turkey Subject: A Sense of Disaster - SATURDAY !! From: Bob Fryer bfryer@............ Date: Fri, 3 Sep 1999 15:46:09 -0700 Hey firefighter friends, It's on again! Saturday, Discovery Channel, 6:00 p.m. PDT -- according to my TV scedule. And -- I have posted this on my webpage. Unfortunately, I will miss Ali's "Seismic Central" party (1999) to be held on Labor Day week-end. (B{(> Take care, Bob Fryer (retired TVFR) --------------- About "A Sense of Disaster" on The Discovery Channel "A Sense of Disaster," a documentary about earthquake prediction sciences outside of the seismological straitjacket, has been rebroadcast on The Discovery Channel. Taped by Granada TV in 1998, the producers covered a wide range of events and efforts that could be described as 'hidden science.' The program tells the story of "earthquake sensitive" people and animals, discusses the electromagnetic basis for the phenomenon, and reports on the successful use of the related sciences to predict earthquakes in China. Some of the most interesting experiments on the electromagnetics are being conducted by Prof. Motoji Ikeya, a physicist at Osaka University. Ikeya is determining whether there is basis-in-fact for many previously unverified earthquake precursor legends. Professor Ikeya was kind enough to send me a list of these projects, early last year. Unfortunately for me, most of his material is published in Japanese. The archaic "not invented here, so it doesn't exist" bias of the seismological community was brought into focus by the pathetic obfuscations of Dr. Robert Geller, at the University of Tokyo, and Dr. Allan Lindh of the US Geologic Survey, Menlo Park, California. Five important areas neglected in the program were: Charlotte King's experience, the basic physics of stressed rocks, the work of the VAN group in Greece, the hidden military technology, and the successful Landers, California prediction in June, 1992. Perhaps it should have been a two-hour program. The average viewer may express some wonderment at the "earthquake sensitive" people video-taped at the 'Fourth Annual Seismic Central Party' (1998) held at Ali Rhoden's home on the San Andreas fault, in the California desert. I can assure you that these are real people, experiencing a real phenomenon, while carrying on with their otherwise ordinary lives. I have enjoyed the generous hospitality of Ali and Steve Rhoden, and their daughter Ashley, for many weeks over the past four years. My own investigations into 'paranormal' perception began in 1965, and focused on earthquake prediction in 1982, after I obtained the full story of Charlotte King who gave a 12-hour warning for the eruption of Mount Saint Helens in 1980. These activities were essentially concurrent with my Fire Department career (1960-1995) in Washington County, Oregon, where I was a Fire & Rescue dispatcher (1966-1985) before transferring to the Fire Marshal's Office. Additional information on "earthquake sensitivity" will be presented on this webpage. Thank you, Bob Fryer ----- earthquake WARNING research ----- --- animals, people, scientific evidence --- --- http://www.teleport.com/~bfryer --- _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Turkey From: Larry Cochrane cochrane@.............. Date: Fri, 03 Sep 1999 15:58:35 -0700 From Edward Cranswick... >Kocaeli Earthquake >Kandilli Observatory >Istanbul, Turkey >Received: from usgs.gov ([193.140.203.93]) >To: Tom Holzer >CC: carver@......... geo_haz_gld@.................. >Subject: Re: Update? > > >Tom- > The website has been updated and >provides a summary of our activities in Turkey. Please forward this message >to the appropriate recipients. > We leave for Golden tomorrow. Thank you for coordinating our activities >here in Turkey. >-Edward > >Tom Holzer wrote: > >> Dave and Ed, >> >> I am curious about how the deployment is going. Did Dave get the >> Toyota-plant K2 on line in time for the M5.2 aftershock? Did all of our >> instruments record it? Did any of you feel it? >> >> What is the present stage of the USGS/Kandilli deployment? Have the >> additional instruments been redeployed and and the origninal deployment >> reconfigured? Has Kandilli been recording on the SSA-2's? >> >> We had an easy, but long trip home. We have been besieged by Bay area >> press, but the earthquake stories are fading from the national press. >> >> I want to say again what a pleasure it was working with you guys. I was >> really impressed by your operation. I think the Survey brass was really >> impressed by the way the whole group performed. I have gotten nothing but >> positive vibes. It made me proud to be part of the effort. >> >> Have a safe trip home in case we do not communicate again. >> >> Tom >> >> -----/\/\/\/\/\/\/\/\/\/\/\/\/\/----------- >> >> Thomas L. Holzer >> U. S. Geological Survey >> 345 Middlefield Road, MS 977 >> Menlo Park, CA 94025-3591 USA >> Voice: 650-329-5637 FAX: 650-329-5163 >> E-mail: tholzer@........ > >-- >Edward Cranswick US Geological Survey Golden, CO 80401 USA >TEL: 303-273-8609 FAX: 303-273-8600 >-------------------------------------------------------------- >Kocaeli Earthquake >Kandilli Observatory >Istanbul, Turkey > > > > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: A Sense of Disaster - SATURDAY !! From: "BONNIE SCHAFER" bschafer@......... Date: Fri, 3 Sep 1999 21:31:52 -0700 hi bob, I AM SO SORRY THAT YOU WON'T BE AT Ali's. you WILL BE MISSED. hopefully, WHEN i COME TO Oregon, NEXT YEAR, WE CAN GET TOGETHER. believe ME YOU WOULDN'T HAVE WANTED WHATEVER i HAD WHILE i WAS THERE THE LAST TIME. i HAVEN'T BEEN THAT SICK IN A LONG TIME. take CARE AND HAVE A GOOD WEEKEND. Bonnie the crafty crafter _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: [Fwd: model and timing] From: Larry Cochrane cochrane@.............. Date: Sun, 05 Sep 1999 03:48:32 -0700 Hi Wayne, At 10:13 PM 9/3/99 -0400, you wrote: >Larry > >The attached email is a response to a timing difference I found while >going through an interim solution which involved data submitted to the >USGS by both the SRU and the DPSN. I found that the P-wave arrived at my >station before SRU stations which were closer to the epicenter. A >station 5km closer to the epicenter had an arrival time 0.15 seconds >later than my station. A few years ago I thought I saw a problem with the local USGS timing. When I looked at the records from the telemetry stations I record compared to the same station recorded by the USGS, I saw a ~150 ms difference. It turned out to be the propagation delay through the low pass filter on my Demod card. At that time I was using two 8 pole switched cap filters. This caused a very long delay through the two filters of about 70 ms each, when the cut-off freq was set to 10 hz. I think the propagation delay changes somewhat with cut-off freq. So I did two things. I removed one of the filter chips (a MAX 291) and added a menu item to SDR called "Filter Delay". This is used to compensate for the filter delay. If your SDR system was locked to the GPS receiver at the time of the event, your timing should be within a few milliseconds. If you see the (L) time indicator in WinQuake, SDR was locked to GPS at the time of the event file. One thing you should check to see is if you have anything in the "Filter Delay" field. I don't think this is the problem because you are seeing the P wave before the expected time. I'm assuming you are looking at the geophone records and not the telemetry records... For the Amp / Filter card with a ~20 hz low-pass filter the delay should be about 50 ms. Too check the timing, heres what you can do. Take the one pulse per second output signal from the GPS receiver and feed it into one of the A/D channels. First do it without the Amp in the path. If the GPS receiver is locked (seeing enough satellites) you know that the 1 pps signal is within 1 us of the correct time. Now create an event file and look at it with WinQuake. The low to high transition should be at the top of each second and within one A/D sample. I haven't tried this but you should also be able to measure the filter delay by feeding the 1pps signal into the amp card. But you MUST divide the signal down with a resistor divider. You don't want to saturate the input. It won't hurt the card, just screw up the measurement. What you want to do is find a resistor value that will keep the output under +- 32k A/D counts. When you look at the event file you should see a rounded signal with some delay from the top of the second. As far as the problem you are having, not sure. Could elevation have something too do with it? Also the type of ground the sensors are over can make a lot of difference. Maybe Edward or others on the PSN-L list have some thoughts.... > >The person who wrote the email, is the volcanologist on island. Do >you have any input on the information he gave me? My comments below... >Wayne Abraham >1430 Rodney Street >Portsmouth, Dominica >hi Wayne >.... > >On the issue of timing, it appears very unlikely that >the problem is with our system. We've invested a lot >of time and technical expertise on this issue, in fact >as recently as the last few months. This could be correct... but when I was working with the local USGS about the timing problem I was seeing with my system and theirs, they did find a problem. At the time they had two systems, one recording the triggered data and another doing the P picks. I pointed out too them that their seismograph records, not the ones form my system, showed a different time for the P arrive then their P picking system. The guy I was working with went over too some equipment and sure enough it was switched to a wrong timing source! Its been a while, I think the error was about 50 ms. They sample at 200 sps. > First, in order >to obtain your quoted accuracy your data sampling rate >would have to be in the region of 20 megahertz. I'm not sure what "quoted accuracy" you gave him. If its a few milliseconds, maybe he thought microseconds, this is not correct. SDR uses a 1 ms interrupt, not the PC time, so timing accuracies can get down to 3 - 5 ms, if used with a GPS receiver. A little more with WWV and WWVB. Since the max sample rate of SDR is 100 sps, or every 10 ms, each sample should have accurate timing. >This >would mean, for a three component station, recording >60 Mb of data per second. Typical sampling rates are >more like 20 Hz, which due to signal processing theory >gives a best possible accuracy on arrival times of >0.1 seconds. Given that it takes a few samples to detect the P wave, 100 ms sounds about right at 20 hz or 50 ms for each sample. If they are only sampling at 20 sps this could be a large part of the error you are seeing. >I say 'best possible' because it takes >much more than using a gps clock to correct the pc >clock, since system limitations end up giving this >timing accuracy an error of +/- 1 second. Again, SDR does not use the PC clock except to seed its internal time when the program first starts up. After that, it uses the 1 ms interrupt generated by the A/D card for all timing, and hopefully some time reference. Since SDR only runs under DOS, there shouldn't be a problem keeping up with the 1 ms interrupt. If the system drops a lot of interrupts (it will do this under Windows), there will be timing problems. You can check for this in the SDR.LOG file if you have the debug mode on. If you see large correction times, you are losing interrupts or some other TSR or driver is disabling interrupts for a long period of time. >We have >been able to by-pass the pc clock and correct the >seismograph clock directly from the gps incoming >data stream, and also sample at 100 Hz. We get an >arrival time accuracy of 20ms as a result. So the >timing discrepancy more likely comes from your system. Running the time signal through the A/D system is one way of doing it... The other way is to control the sampling and timing the way SDR, and I'm sure other data logging systems, do it.... -Larry Cochrane Redwood City, PSN _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: New SDR release From: Larry Cochrane cochrane@.............. Date: Sun, 05 Sep 1999 19:14:22 -0700 Greetings, Today I released a new version of SDR. This is version 2.7. Its mostly a bug fix release. Several people reported a problem in the replay mode when you used a high value for the X-Scale. I finally tracked down the problem. A link to download the new release can be found here: http://www.seismicnet.com/sdrdocs/sdr.htm This page also has a What's New section describing the new features in this release. Regards, Larry Cochrane Redwood City, PSN _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: A Sense of Disaster - SATURDAY !! From: "Robert Sailor" rob888@........... Date: Mon, 06 Sep 1999 11:58:30 PDT Bonnie, I received the following, but we do not know one another. I live in San Diego and am getting this mailing incorrectly. Please check you address. mine is rob888@........... >From: "BONNIE SCHAFER" >Reply-To: PSN-L Mailing List >To: "PSN-L Mailing List" >Subject: Re: A Sense of Disaster - SATURDAY !! >Date: Fri, 3 Sep 1999 21:31:52 -0700 > >hi bob, > >I AM SO SORRY THAT YOU WON'T BE AT Ali's. you WILL BE MISSED. > >hopefully, WHEN i COME TO Oregon, NEXT YEAR, WE CAN GET TOGETHER. believe >ME YOU WOULDN'T HAVE WANTED WHATEVER i HAD WHILE i WAS THERE THE LAST TIME. >i HAVEN'T BEEN THAT SICK IN A LONG TIME. > >take CARE AND HAVE A GOOD WEEKEND. > >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 ______________________________________________________ Get Your Private, Free Email at http://www.hotmail.com _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: VBB Circuit Cards From: "Rex Klopfenstein, Jr." rklopfen@......... Date: Mon, 06 Sep 1999 16:56:49 -0400 I finally got around to posting the pictures of my VBB circuit cards. Haven't tested them yet, got to build the frame to support the VRDT. -- Rex Klopfenstein, Jr. Bowling Green, OH rklopfen@......... http://www.wcnet.org/~rklopfen _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: A Sense of Disaster - SATURDAY !! From: Bob Fryer bfryer@............ Date: Mon, 6 Sep 1999 15:01:21 -0700 Hi Rob, Bonnie's reply to me went to the list by mistake. Easy enough error, even when you CAN see the screen. Take care, Bob Fryer >Bonnie, > >I received the following, but we do not know one another. I live in San >Diego and am getting this mailing incorrectly. Please check you address. >mine is rob888@........... > > >>From: "BONNIE SCHAFER" >>Reply-To: PSN-L Mailing List ----- earthquake WARNING research ----- --- animals, people, scientific evidence --- --- http://www.teleport.com/~bfryer --- _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Geophone group buy - Last call.... From: Larry Cochrane cochrane@.............. Date: Tue, 07 Sep 1999 00:29:06 -0700 All, Heres an update on the PSN geophone group buy. Last night I sent out a series of emails informing everyone of the status of their order. I ended up splitting up the order. I got about 1/2 of checks right away, so I ask Jim at Mitcham if it was ok to order some now and then place another order when I get the rest of the checks in. I currently wafting for this group of sensors too arrive. So there is still time if anyone is interested. I currently have two checks in house and am waiting for 4 or 5 more to come in. I want to get this over with, so I think I will set a cut off date of mid next week or around Sept 15. At that time I will place the second and last order (for awhile) with Mitcham. Any checks received after the cut off date will be returned. This is the message I sent out list month about the group buy. Please note that the sensors are used.... It looks like the final cost for the sensors will be $295.00 for the 1 hz device and $37.00 for the 4.5 hz sensor. These prices include the cost for shipping the sensors from Texas to Redwood City, Ca, but not the cost to ship the sensor to the user. I'm not sure what the weight is for the sensors, or what type of box and packing material I will need, so its hard to give an exact price. My guess is that for the 1 hz sensor shipping cost will be around $15.00 to $20.00 to addressed in the US, more for out of the country orders. Maybe a little less for orders here in California. For the 4.5 hz device the shipping cost should be about 1/2 the price. Too get the ball rolling lets do this. If you ordered one 1 hz sensor and you live in the US send me a check for $312.00. If you ordered one of the 4.5 hz device send me a check for $45.00. If the shipping cost ends up being a lot less or a lot more I will send you a refund or ask for more $. If you ordered more then one sensor the shipping cost should be a little less. I will contact you directly with a price. I will also contact you directly if you live outside of the US. Please make your check out to me and send it too: Larry Cochrane 24 Garden Street Redwood City, Ca. USA 94063 Regards, Larry Cochrane Redwood City, PSN _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Link to the HS 10-1 Geophone From: Larry Cochrane cochrane@.............. Date: Tue, 07 Sep 1999 01:23:45 -0700 All, I found this link to the 1 hz geophone that Mitcham Industries is selling us: http://www.geospacecorp.com/hs10.htm. I don't know what the coil resistance is yet. I couldn't find any specs online for the 4.5 hz Mark L10B sensor. -Larry Cochrane Redwood City, PSN _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: quake in progress From: "Liberio Rossi" l.rossi@....... Date: Tue, 7 Sep 1999 14:26:05 +0200 big quake in progress, maybe north europe... (starting at 12.04 GMT) regards, Liberio (43=B054'79"N, 10=B031'56"E) _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: AEGEAN LARGE QUAKE From: "Francesco" franuc@...... Date: Tue, 7 Sep 1999 14:32:58 +0200 preliminary location: 11.56.20 Mb 5.8 Loc.: 37.4.N 26.3E Central Aegean Sea, Dodecanese Islands
preliminary location:
 
11.56.20
Mb 5.8
Loc.: 37.4.N   26.3E  = Central=20 Aegean Sea, Dodecanese Islands
Subject: Running SDR & WinQuake on same PC From: jimo17@........ Date: Tue, 7 Sep 1999 05:42:21 -0700 Hi Larry and Others; I would like to run SDR- say all 6 channels @ 100sps, using WWVB for time, on my HP Pavilion: 200MHz Processor 96Mb Ram 4 GB of HD I would also like to run WinQuake in the background, as well as surf the Internet and download large files occasionally. Is this permissible or would I run into problems? What other method would you recommend? Jim _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Book From: jmhannon@.................... Date: Tue, 7 Sep 1999 08:07:12 -0500 Does anyone know anything about this book? "Earthquakes, Mechanisms and Detection. An Amateur Primer" by Jeffrey M. Lichtman This 75 page, basic beginners publication, is for those interested in doing research and assembling a simple seismograph. Included are history, people, and how-to projects. Jim Hannon _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: wrong address From: "Robert Sailor" rob888@........... Date: Tue, 07 Sep 1999 10:01:07 PDT Hello, For some reason I seem to be on your listserve. I just opened a Hotmail account and the first time I looked at it, it contained lots of mail from your list. Please remove me. It's all very interesting and I'm pleased to get mail, but I worry that whomever is supposed to receive what is being sent to me is leading an all-too quiet life. Robert rob888@........... ______________________________________________________ Get Your Private, Free Email at http://www.hotmail.com _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Seismic data From: Daniel Gammon dgammon@......... Date: Tue, 07 Sep 1999 16:20:08 -0400 Does anyone know of studies or seismic data associated with rocket launches or static engine testing? I am interested in the sesimic source levels corresponding to different rockets. Thanks for your help! Dan Gammon _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Strong motion for Santa Cruz mountain home From: Edward Cranswick cranswick@........ Date: Tue, 07 Sep 1999 16:13:58 -0600 John- This is a very interesting email. -Edward "John R. Evans" wrote: > Doug, > > Thank you for your enthusiastic and thoughtful response to > my e-mails on the ICS-3028 accelerometer design. By Cc: of > this e-mail, I'm soliciting key colleagues' thoughts on the > issues. > > YES, the thought of gillions of strong-motion sensors on-line > is extremely interesting to us. Indeed, we've been nurturing such > fantasies for some time, and are in the process of working toward > a "big science" solution (well, big for us anyway). But we would > also be very interested in a good small-science/amateur solution, > to augment any array we might eventually build. PSN and similarly > interested folks could make a truly valuable contribution, given > the extreme spatial variability of shaking strength, the need for > detailed data to test models and improve building codes, and the > skills and dedication shown by you folks over the years. > > A suggestion: I could try to get some official "outreach" > money or even a little internal "Team" money (we're talking > small dollars and moderate staff time) to create a 3-accel > redesign and make a large purchase of these boards possible. > USGS could buy that bunch of boards and make them available > to those showing serious interest (PSN, high-school science > teachers, etc.). As you point out, the board is the hardest > bit to do in small quantities. I'm sure between you and other > PSN members, the appropriate software will follow shortly. > > (Also, there may be a commercial solution not too far off, I'd > guess for in the neighborhood of $1000, but nothing is firm.) > > You and like minded folks could then make a group purchase of > the other parts. (ICS is in Milpitas, and they sell through an > EG&G building in Santa Clara. They take Visa and doubtless other > forms of green.) The only other hard parts to find are the low- > value trimming resistors (must be metal film, should be low Ct, > should be low wattage to fit the board and keep leads short, as > must be). I have the start of a comprehensive collection here > and we might find a way to help each other make a more extensive > central stash for all to draw from. There may be a significant > advantage in buying the Op Amps and thermistors in bulk too, and > you might want to buy a bunch of mounting blocks from a machinist > somewhere. > > Yes, that's three acceleration channels and one temperature. > The design does not compensate for temperature variation of > sensitivity (too noisy), which is done digitally in the data > collection system (ICS supplies the needed, serial-number- > specific coefficients). I have software to help select pairs > of compensating resistors from any pool, by the way. > > We would offer guidance on siting to get "free field" sites. > Basically, anyone with a one- or two-story wood-frame house > and a garage, utility room, or outbuilding with a grade-level > slab (and no basement beneath) has a nearly ideal spot--one > we've had our eyes on for several years. Such structures are > light and have little effect on the seismic signal (i.e., they > have minimal "soil-structure interaction"). The accelerometers > need to be rigidly affixed to the slab, preferably away from > large noise sources like washing machines. They also need some > insulation to keep air circulation down and slow the temperature > changes. Any decent chunk of urethane foam will do the trick. > > My schedule these days is totally nuts, but this is something > I could probably fit in over the next year. Alternatively, I > could give guidance and let someone else do the legwork of the > board re-design. Indeed, the notion of making kits available > might get PSN's interest? (Anyone out there interested in > making a single-board with 18-bit ADCs on it too?) In any > case, someone else will have to do any resistor pulling from > the central stash (I can't afford to offer my time for that, > but we could at least build upon my existing $1200 stash). > > We already accept Internet reports of MMI (Modified Mercalli > Intensity--observations of local earthquake effects/damage) so > adding a semi-secure port for shaking metrics would probably be > straightforward. We would be interested in shaking metrics (peak > accelerations, peak velocities, etc.--we can help with software) > in the first minutes after an event to help build our ShakeMap > images. We would be extremely interested in the waveforms too > (after a few hours or days) and could be a good release route > for those data, if you desire. That availability could make the > waveforms very valuable for the structural engineering community > as well, though they are a very conservative lot (since they can > be sued if they goof). Appropriate caveats would have to be > attached to the waveforms ("amateur generated--use at your own > risk" or something like that). I think it would be worth our > investment in software if there were hundreds or more of sites. > > Realize that I'm not yet able to offer an "official" proposal. > This is part of the discussion that could lead to a proposal > within the USGS to do some or all of what I suggest here. It > would help for that process if you got some firm measure of the > number of folks with serious, immediate interest, at least in > PSN. Given our various experiences with asking for help siting > our own instruments, I suspect there would be lots of interest, > with the main negative the need to build and maintain it > yourself. > > I don't know why Guralp is non-responsive. For PEPP, contact > Prof. Robert Phinney (rphinney@............... Bob can point > you to the right person to answer your questions. (Bob: any > thoughts on bringing PEPP into this to make strong-motion > available to science teachers?) > > Best wishes, > John > jrevans@........ > > ----------------------------------------------------------- > > Doug wrote: > > > > On Thu, 26 Aug 1999, you wrote: > > > > > I have a design for a good but relatively inexpensive (ca. > > > $500 parts for three components) strong-motion sensor. > > > > This is excellent. Thank you for the information. > > > > I took a look at the report and component listing, and it > > looks really interesting. But I am wondering how hard it > > will be to source parts in single quantities, and also > > the production of the PCB board would be very difficult > > for me. I am very interested in getting a strong motion > > sensor set up like the one you outlined, and the cost is > > not a problem. But do I have to build it from scratch? > > Any ideas on how I might get an assembled one, or at > > least a PCB board for it? It appears to be exactly what > > I am looking for but I'm a software guy and I'm not sure > > I'm up to the task of putting it together from scratch. > > Any ideas or suggestions? I'd sure like to try hooking > > up ethernet to this 3028-based sensor. > > > > > You will need four channels (the fourth for temperature) > > > if you use it. > > > > Is that three ICS-3028s and one thermistor? > > > > > PEPP would be interesting and useful too (Susan Schwartz at > > > UCSC would like some teleseismic records, I'm sure, to look > > > at anisotropy) but strong-motion is my passion (and bias!). > > > > I am very interested in the PEPP system also, and intend > > to get one. Strangely though I can't seem to get a reply > > from the people at Guralp. I sent two emails to their > > north american sales rep asking for pricing and how to > > order, but no reply so far. Any idea who I might talk to > > to get one the CMG-PEPP units? > > > > Thanks, > > Doug > > > > PS. It would be really interesting to put together a fairly > > low cost yet useful strong motion sensor that could be > > plug-and-play on the internet, automatically joining a > > "federation" of other sensors. It would be cool to > > have a station that anyone can use, with software that > > automatically sends event data to a site on the net > > that USGS could use for analysis. One could imagine > > 1000s of these sensors plugged into everyday networks > > all around the san andreas, imagine how much data > > could be gathered! -- 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) Subject: Re: Book From: CARRJJ@....... Date: Tue, 7 Sep 1999 18:23:33 EDT Jeff Lichtmann is a subscriber to this network I believe. He is on the net, but I don't have his e-mail address (Jeff....can you accommodate me!?!). At any rate, he is the owner of Radio Astronomy Supplies. Joe Carr _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Running SDR & WinQuake on same PC From: Arie Verveer ajbv@............ Date: Wed, 08 Sep 1999 08:36:52 +0800 Hi Jim, As I understand, SDR uses interrupts for timing. This timing interrupt must have priority over "windows" but "Windows" wont allow this. Thus "SDR" should be run in a "Dos" only mode. One easy solution is to run a second computer networked to your "Windows" machine. This (+486) computer runs "SDR" in a Dos only mode. Larry's has some good Doc's on this. Winquake can request files from the "SDR" computer while you have full windows functionality. I use this method all the time and it works well. Regards Arie > > > I would like to run SDR- say all 6 channels @ 100sps, using WWVB for > time, on my HP Pavilion: > 200MHz Processor > 96Mb Ram > 4 GB of HD > > I would also like to run WinQuake in the background, as well as surf the > Internet and download large files occasionally. Is this permissible or > would I run into problems? What other method would you recommend? > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: quake in progress From: "Anders Heerfordt" aheerfor@...... Date: Wed, 8 Sep 1999 07:41:14 +0200 The quake was around 10 km north of Athens, Greece, according the radio broadcast this morning. Some collapsed buildings, maybe a hundred dead, maybe two thousand wounded. They said thay had located around 60 still living people, trapped in the ruins. Two million people in Athens slept in the streets tonight. Regards, Anders _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Book From: Doug doug@............. Date: Wed, 8 Sep 1999 01:38:14 -0700 Jim Hannon wrote: > Does anyone know anything about this book? > "Earthquakes, Mechanisms and Detection. An Amateur Primer" > > by Jeffrey M. Lichtman No, but the name rang a bell, and sure enough I found the same name on a radio astronomy page. Seems that Jeffery does a lot of work in radio astronomy including this book: http://www.nitehawk.com/rasmit/jml_bk.html In addition to this seismic fascination, I've been exploring the basics of radio astronomy. Very interesting. And similar to seismology in quite a few ways. Radio "viewing" is much like seismic recording: you have a weak signal, you pass it through amp/filters, you do analog/digital sampling, then send it to a chart recorder or data file. The challenges are also similar in getting a S/N ratio and timing system that makes the data useful. It appears that almost all of the relevant technology aside from the sensor/antenna itself is the same. I found this very interesting place a while ago: http://www.nitehawk.com/rasmit/jm_10.html They have the high end SETI systems and hydrogen line spectrometers, but they also have some low-cost amplifiers tuned to frequencies to monitor jupiter noise storms and solar activity. I am contemplating trying to monitor some jupiter activity here just for kicks. Hey -- I just realized that it was Jefferey M. Lichtman who answered my questions about the jupiter and solar systems: >Hi Doug, > >Here are your answers: > >> 1) What additional equipment would I need to use these radio >> telescope units? Please advise on what type of antennas, >> filters, and anything else that would be required to get a >> minimal/simple system going. > >Full instructions for a standard wire dipole are given for the >Jupiter system. The VLF comes with the dipole wire, as were the >Jupiter one does not. > >In addition, the VLF can be equipped with a 12 Bit A/D converter >and software, for an additional $50.00. This way, you can attach >that to a simple 286 or higher IBM type computer. > >>2) I want to capture the signals to a host computer, so I >> assume that some kind of analog/digital converter will be >> required. Please recommend what type of card/software >> would be appropriate (ie what resolution etc would I need)? > >Answered above for the VLF. The Jupiter receiver will work with the >Radio Sky Data Collect Lite Software and their A/D unit (must be built). > >> 3) Are you aware, or can you recommend any software that >> would be appropriate for use with the RF2001A and VLD Solar >> radio telescopes? > >Same as above. > >> 4) Are the instructions that come with the RF2001A and VLF Solar >> telescopes detailed enough for a radio astronomy newbie to >> get a system running and recording signals? If not, how >> else can I get that information? > >Yes! > >> 5) Where can I find more information about Jupiter storm >> monitoring and solar activity monitoring as it relates to >> your products? >> >Many sources on the web about both subjects, also in our books. > >> - Does Mr Dick Flagg have information on the web or in books >> or other resources about jupiter monitoring? > >No > >> - What books would you recommend to a newbie trying to do >> simple radio astronomy, assumijng that I'm starting with >> jupiter storms and solar studies? > >Radio Astronomy Handbook by Sickels, also check our website links. > >> 6) Are amatuer radio licences or other licences required to >> operate your products, and if so, which require licences? >> Would I need a license to operate the Ultra Cyber or the >> Seeker 2000 for example? > >Licenses are required ONLY on transmitting equipment. Not on receivers. > >Hope this info helps. Let us know if we can be of further service. > > >Best Regards, >Jeffrey M. Lichtman >Radio Astronomy Supplies >http://www.nitehawk.com/rasmit/ras.html _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Book From: Raul Alvarez ralvarez@........ Date: Wed, 08 Sep 1999 07:34:32 -0600 Hi all, I have known Jeff for some time. He is very active and knowledgeable in radio astronomy. He was one of the founder of SARA the society of amateur radio astronomy. Raul Doug wrote: > Jim Hannon wrote: > > > Does anyone know anything about this book? > > "Earthquakes, Mechanisms and Detection. An Amateur Primer" > > > > by Jeffrey M. Lichtman > > No, but the name rang a bell, and sure enough I found the same name on a > radio astronomy page. Seems that Jeffery does a lot of work in radio > astronomy including this book: > > http://www.nitehawk.com/rasmit/jml_bk.html > > In addition to this seismic fascination, I've been exploring the basics > of radio astronomy. Very interesting. And similar to seismology in quite > a few ways. Radio "viewing" is much like seismic recording: you have a > weak signal, you pass it through amp/filters, you do analog/digital > sampling, then send it to a chart recorder or data file. The challenges > are also similar in getting a S/N ratio and timing system that makes > the data useful. It appears that almost all of the relevant technology > aside from the sensor/antenna itself is the same. I found this very > interesting place a while ago: > > http://www.nitehawk.com/rasmit/jm_10.html > > They have the high end SETI systems and hydrogen line spectrometers, > but they also have some low-cost amplifiers tuned to frequencies to > monitor jupiter noise storms and solar activity. I am contemplating > trying to monitor some jupiter activity here just for kicks. > > Hey -- I just realized that it was Jefferey M. Lichtman who answered > my questions about the jupiter and solar systems: > > >Hi Doug, > > > >Here are your answers: > > > >> 1) What additional equipment would I need to use these radio > >> telescope units? Please advise on what type of antennas, > >> filters, and anything else that would be required to get a > >> minimal/simple system going. > > > >Full instructions for a standard wire dipole are given for the > >Jupiter system. The VLF comes with the dipole wire, as were the > >Jupiter one does not. > > > >In addition, the VLF can be equipped with a 12 Bit A/D converter > >and software, for an additional $50.00. This way, you can attach > >that to a simple 286 or higher IBM type computer. > > > >>2) I want to capture the signals to a host computer, so I > >> assume that some kind of analog/digital converter will be > >> required. Please recommend what type of card/software > >> would be appropriate (ie what resolution etc would I need)? > > > >Answered above for the VLF. The Jupiter receiver will work with the > >Radio Sky Data Collect Lite Software and their A/D unit (must be built). > > > >> 3) Are you aware, or can you recommend any software that > >> would be appropriate for use with the RF2001A and VLD Solar > >> radio telescopes? > > > >Same as above. > > > >> 4) Are the instructions that come with the RF2001A and VLF Solar > >> telescopes detailed enough for a radio astronomy newbie to > >> get a system running and recording signals? If not, how > >> else can I get that information? > > > >Yes! > > > >> 5) Where can I find more information about Jupiter storm > >> monitoring and solar activity monitoring as it relates to > >> your products? > >> > >Many sources on the web about both subjects, also in our books. > > > >> - Does Mr Dick Flagg have information on the web or in books > >> or other resources about jupiter monitoring? > > > >No > > > >> - What books would you recommend to a newbie trying to do > >> simple radio astronomy, assumijng that I'm starting with > >> jupiter storms and solar studies? > > > >Radio Astronomy Handbook by Sickels, also check our website links. > > > >> 6) Are amatuer radio licences or other licences required to > >> operate your products, and if so, which require licences? > >> Would I need a license to operate the Ultra Cyber or the > >> Seeker 2000 for example? > > > >Licenses are required ONLY on transmitting equipment. Not on receivers. > > > >Hope this info helps. Let us know if we can be of further service. > > > > > >Best Regards, > >Jeffrey M. Lichtman > >Radio Astronomy Supplies > >http://www.nitehawk.com/rasmit/ras.html > > _____________________________________________________________________ > > 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) Subject: Re: Open House Photos on Web From: Edward Cranswick cranswick@........ Date: Wed, 08 Sep 1999 07:37:24 -0600 Meredith- Wonderful pictures! Even though I missed Open House because I was in Turkey, I've seen it at your website! -Edward John Lahr wrote: > Hi Team, > > Check out the great photos that Meredith Lamb took at the Open House > on Saturday. I think he did a fantastic job and was sure quick in > making them available. Meredith is an amateur seismologist, member > of the Public Seismic Network, and runs his own seismic observatory! > > Open House Pictures start here: > > http://members.xoom.com/seismogram/page32.html > > Meredith's Observatory: > > http://www.users.uswest.net/~psnseismograph52/Index.html > > JCLahr -- 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) Subject: Re: Running SDR & WinQuake on same PC From: "Rex Klopfenstein, Jr" rklopfen@......... Date: Wed, 08 Sep 1999 09:57:56 -0400 Now you have something to do with that old 486!! I too have the same setup and with the pricing of network cards it doesn't cost much. By the way, a 486/66 works just fine! I saw several at garage sales for $25!! Arie Verveer wrote: > Hi Jim, > > One easy solution is to run a second computer networked to your "Windows" machine. > This (+486) computer runs "SDR" in a Dos only mode. -- Rex Klopfentein, Jr. rklopfen@......... http://www.wcnet.org/~rklopfen _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Running SDR & WinQuake on same PC From: Larry Cochrane cochrane@.............. Date: Wed, 08 Sep 1999 17:23:57 -0700 Jim, As Arie pointed out, SDR needs to run under DOS because Windows disables interrupts for long periods of time. This causes SDR to loose time. You can run everything on one computer, you can run SDR under DOS, exit SDR and then boot to Windows to run WinQuake. Not very eloquent...The best thing to do is network two systems and have the SDR system place event files on the drive of the system running Windows and WinQuake. The disadvantage is you need to run two systems all of the time. Since SDR only needs a DOS system to run, a 66mhz 486 system is perfect for data logging and at this point very cheap, if not free. The only problem with older 486's is most are not Y2K compliant. A Y2K card can fix this or you can set the time each time the system reboots. Hope this helps... -Larry Cochrane Redwood City, PSN At 05:42 AM 9/7/99 -0700, you wrote: >Hi Larry and Others; > >I would like to run SDR- say all 6 channels @ 100sps, using WWVB for >time, on my HP Pavilion: >200MHz Processor >96Mb Ram >4 GB of HD > >I would also like to run WinQuake in the background, as well as surf the >Internet and download large files occasionally. Is this permissible or >would I run into problems? What other method would you recommend? > >Jim _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: GPS location From: EK kerls@...... Date: Wed, 08 Sep 1999 22:57:05 -0500 Dear seismic net ; S.O.D.A.T. is looking for VOLUNTEERS to test a new Earthquake Precursor Monitor System. What we are looking for is people that live no closer than 5 miles, but not over 10 miles west of a fault line. To volunteer we need to now your GPS location and the GPS point due west of you on the fault line. You will also need to E-mail us at any change on the GVR units, along with the time of the action. For more information go to; www.geocities.com/CapeCanaveral/Hall/1110/earthquake.html Maj. Edward E. Kerls A.R. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: One more time... Update on the geophone group buy From: Larry Cochrane cochrane@.............. Date: Wed, 08 Sep 1999 21:30:07 -0700 All, The first batch of sensors arrived today. They look like they are in good condition. I took some pictures of them with my digital camera (a RICOH 4200 I bought a few months ago) and made a web page at http://www.seismicnet.com/geophone/index.html. The coil resistance for the 1 hz devices is around 400 ohms and the 4.5 hz sensors around 220 ohms. This gives the 1 hz device a sensitivity of 2.99 V/ ips (volts per inch per second). I currently have one of the 1 hz units on line. The event file extension is *.lc9. This replaces the *.lc2 channel that was connected to a 4.5 hz vertical sensor. If I had more free channels I would record both. I'll see if I can set up another SDR system so I can monitor both type of sensors simultaneously. -Larry Cochrane Redwood City, PSN _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: The Planet That Hums article... From: meredith lamb mlamb1@.......... Date: Wed, 08 Sep 1999 21:15:41 +0000 Hi all, Note a internet address with an article of interest: http://www.newscientist.com It has the 5 page article on "The Planet That Hums", and, "Disaster this week-landslides", which goes alittle bit into the island of Hawaii's past history and current potential for land slides. The planet that hums goes into history and current thought with high frequency background noise. Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Running SDR & WinQuake on same PC From: Doug doug@............. Date: Wed, 8 Sep 1999 22:50:58 -0700 On Wed, 08 Sep 1999, you wrote: > Since SDR only needs a DOS system to run, a 66mhz 486 system is perfect for > data logging and at this point very cheap, if not free. Here's one on ebay for $49 with 1GB storage http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=158538466 -- Doug _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: GPS location From: Larry Cochrane cochrane@.............. Date: Wed, 08 Sep 1999 23:26:40 -0700 Edward, OK, I'll bite... I live about 5 to 10 miles from the San Andreas fault, but I'm east of the fault. What's the difference and why the narrow distance??? -Larry Cochrane Redwood City, PSN At 10:57 PM 9/8/99 -0500, you wrote: >Dear seismic net ; > S.O.D.A.T. is looking for VOLUNTEERS to test a new Earthquake >Precursor Monitor System. What we are looking for is people that live no >closer than 5 miles, but not over 10 miles west of a fault line. > To volunteer we need to now your GPS location and the GPS point >due west of you on the fault line. You will also need to E-mail us at >any change on the GVR units, along with the time of the action. > For more information go to; >www.geocities.com/CapeCanaveral/Hall/1110/earthquake.html > > > Maj. Edward E. Kerls A.R. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: GPS location From: EK kerls@...... Date: Thu, 09 Sep 1999 04:55:26 -0500 Dear Mr. Cochrane; In short, the Earth's core has been found to rotate about two degrees faster, [ or about 0.36 miles per hour] than the Earth's crust. And sence the core is where gravity comes from, thus gravity cuts across the crust at that rate. But the core is not smooth , it has peeks and valleys just like the surface does. It is theses wave forms that we are looking for because a valley would lower the density level of gravity that is rising to the fault line that is holding it in place.. This allows the westword movement of the plates to move. Of course you would want to detect these waves before they get to the fault line. This is why you need to be to the west of the fault line for a good waring time. Maj. Edward E. Kerls A.R. Larry Cochrane wrote: > Edward, > > OK, I'll bite... I live about 5 to 10 miles from the San Andreas fault, but > I'm east of the fault. What's the difference and why the narrow distance??? > > -Larry Cochrane > Redwood City, PSN > > At 10:57 PM 9/8/99 -0500, you wrote: > >Dear seismic net ; > > S.O.D.A.T. is looking for VOLUNTEERS to test a new Earthquake > >Precursor Monitor System. What we are looking for is people that live no > >closer than 5 miles, but not over 10 miles west of a fault line. > > To volunteer we need to now your GPS location and the GPS point > >due west of you on the fault line. You will also need to E-mail us at > >any change on the GVR units, along with the time of the action. > > For more information go to; > >www.geocities.com/CapeCanaveral/Hall/1110/earthquake.html > > > > > > Maj. Edward E. Kerls A.R. > > _____________________________________________________________________ > > 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) Subject: PSN - Y2K Cards? From: "Rex Klopfenstein, Jr" rklopfen@......... Date: Thu, 09 Sep 1999 08:55:07 -0400 I am trying to decide to upgrade the motherboard or install a Y2K card in my SDR (486/66) computer. Can anybody point me to a source of a cheap Y2K card. I have seen a few for around $90, at that price I'll look for a cheap Pentum motherboard! Thanks in advance -- Rex Klopfentein, Jr. rklopfen@......... http://www.wcnet.org/~rklopfen _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: The Planet That Hums article... From: Arie Verveer ajbv@............ Date: Thu, 09 Sep 1999 21:56:24 +0800 Hi Meredith, Interesting article. A few months ago a chap contacted me, who is working on a "Phd" on 3D sound modelling? . Anyhow, he wanted a months worth of seismic data, which I sent him. After a few weeks he sent me the same data that was turned into a "Wave" file. When I played the "CD" it was amazing to hear the seismic events and background noise. The big quakes sound like thunder with pop's and clicks. I identified some of these as "PcS" waves. Its amazing. The earth is worth listening too . Arie meredith lamb wrote: > > Note a internet address with an article of interest: > > http://www.newscientist.com > > It has the 5 page article on "The Planet That Hums", and, _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Running SDR & WinQuake on same PC From: Karl Cunningham karlc@....... Date: Thu, 09 Sep 1999 08:41:32 -0700 Jim -- To add a bit to what Larry said, you can run networked SDR and Winquake without having the Winquake machine on all the time, but it takes a bit of effort on your part when you start the Winquake machine. You need to set up two configurations for SDR (one networked and the other not) and be able to switch between them. When you turn the Winquake machine on, you then go to the SDR machine and start the networked SDR configuration and copy event files to the Winquake machine. When you are ready to turn off the Winquake machine, you go to the SDR machine and switch SDR back to the non-networked configuration so it will save event files to its local hard disk. I did this for over a year (for other reasons I leave my Winquake machine on all the time now), and used DOS batch files to change the configurations back and forth. If you are interested, I can give more details. Karl Cunningham La Mesa, CA. PSN station #40 karlc@....... _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: The Planet That Hums article... From: John Lahr lahr@................... Date: Thu, 9 Sep 1999 10:06:23 -0600 (MDT) Meredith, Thanks for the heads up on the interesting hum story! JCLahr _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: TURKEY: Re: Strong motion for Santa Cruz mountain home From: Edward Cranswick cranswick@........ Date: Thu, 09 Sep 1999 10:53:57 -0600 PSN and others- There is a large number of people in Turkey at right now -- several tens of millions -- who are in an excited state because of the Izmet Earthquake , and many would be interested in having some kind of seismograph to monitor weak/strong ground motions. I saw more cell-phones in Istanbul than I have seen anywhere else; the populace is definitely hardware conscious. The only thing they don't have is a cheap, reliable seismic data acquisition unit built in the same mode as a PC computer; you take it out of the box, plug it in, and it starts working. Something like a Kinemetrics K2, but an order-of-magnitude cheaper, i.e., less than a $1000. So the interest is there; where is the device? -Edward Bob Phinney wrote: > To: John Evans and friends... > PEPP has been locked in amber for a year while we have haggled with NSF > education folks about continued funding. We now are funded. > > GaryPavlis: check the bottom for my response. > > "John R. Evans" wrote: > > > > Doug, > > > > Thank you for your enthusiastic and thoughtful response to > > my e-mails on the ICS-3028 accelerometer design. By Cc: of > > this e-mail, I'm soliciting key colleagues' thoughts on the > > issues. > > > > YES, the thought of gillions of strong-motion sensors on-line > > is extremely interesting to us. Indeed, we've been nurturing such > > fantasies for some time, and are in the process of working toward > > a "big science" solution (well, big for us anyway). But we would > > also be very interested in a good small-science/amateur solution, > > to augment any array we might eventually build. PSN and similarly > > interested folks could make a truly valuable contribution, given > > the extreme spatial variability of shaking strength, the need for > > detailed data to test models and improve building codes, and the > > skills and dedication shown by you folks over the years. > > > > A suggestion: I could try to get some official "outreach" > > money or even a little internal "Team" money (we're talking > > small dollars and moderate staff time) to create a 3-accel > > redesign and make a large purchase of these boards possible. > > USGS could buy that bunch of boards and make them available > > to those showing serious interest (PSN, high-school science > > teachers, etc.). As you point out, the board is the hardest > > bit to do in small quantities. I'm sure between you and other > > PSN members, the appropriate software will follow shortly. > > > > (Also, there may be a commercial solution not too far off, I'd > > guess for in the neighborhood of $1000, but nothing is firm.) > > > > You and like minded folks could then make a group purchase of > > the other parts. (ICS is in Milpitas, and they sell through an > > EG&G building in Santa Clara. They take Visa and doubtless other > > forms of green.) The only other hard parts to find are the low- > > value trimming resistors (must be metal film, should be low Ct, > > should be low wattage to fit the board and keep leads short, as > > must be). I have the start of a comprehensive collection here > > and we might find a way to help each other make a more extensive > > central stash for all to draw from. There may be a significant > > advantage in buying the Op Amps and thermistors in bulk too, and > > you might want to buy a bunch of mounting blocks from a machinist > > somewhere. > > > > Yes, that's three acceleration channels and one temperature. > > The design does not compensate for temperature variation of > > sensitivity (too noisy), which is done digitally in the data > > collection system (ICS supplies the needed, serial-number- > > specific coefficients). I have software to help select pairs > > of compensating resistors from any pool, by the way. > > > > We would offer guidance on siting to get "free field" sites. > > Basically, anyone with a one- or two-story wood-frame house > > and a garage, utility room, or outbuilding with a grade-level > > slab (and no basement beneath) has a nearly ideal spot--one > > we've had our eyes on for several years. Such structures are > > light and have little effect on the seismic signal (i.e., they > > have minimal "soil-structure interaction"). The accelerometers > > need to be rigidly affixed to the slab, preferably away from > > large noise sources like washing machines. They also need some > > insulation to keep air circulation down and slow the temperature > > changes. Any decent chunk of urethane foam will do the trick. > > > > My schedule these days is totally nuts, but this is something > > I could probably fit in over the next year. Alternatively, I > > could give guidance and let someone else do the legwork of the > > board re-design. Indeed, the notion of making kits available > > might get PSN's interest? (Anyone out there interested in > > making a single-board with 18-bit ADCs on it too?) In any > > case, someone else will have to do any resistor pulling from > > the central stash (I can't afford to offer my time for that, > > but we could at least build upon my existing $1200 stash). > > > > We already accept Internet reports of MMI (Modified Mercalli > > Intensity--observations of local earthquake effects/damage) so > > adding a semi-secure port for shaking metrics would probably be > > straightforward. We would be interested in shaking metrics (peak > > accelerations, peak velocities, etc.--we can help with software) > > in the first minutes after an event to help build our ShakeMap > > images. We would be extremely interested in the waveforms too > > (after a few hours or days) and could be a good release route > > for those data, if you desire. That availability could make the > > waveforms very valuable for the structural engineering community > > as well, though they are a very conservative lot (since they can > > be sued if they goof). Appropriate caveats would have to be > > attached to the waveforms ("amateur generated--use at your own > > risk" or something like that). I think it would be worth our > > investment in software if there were hundreds or more of sites. > > > > Realize that I'm not yet able to offer an "official" proposal. > > This is part of the discussion that could lead to a proposal > > within the USGS to do some or all of what I suggest here. It > > would help for that process if you got some firm measure of the > > number of folks with serious, immediate interest, at least in > > PSN. Given our various experiences with asking for help siting > > our own instruments, I suspect there would be lots of interest, > > with the main negative the need to build and maintain it > > yourself. > > > > I don't know why Guralp is non-responsive. For PEPP, contact > > Prof. Robert Phinney (rphinney@............... Bob can point > > you to the right person to answer your questions. (Bob: any > > thoughts on bringing PEPP into this to make strong-motion > > available to science teachers?) > > > > Best wishes, > > John > > jrevans@........ > > > > ----------------------------------------------------------- > > > > Doug wrote: > > > > > > On Thu, 26 Aug 1999, you wrote: > > > > > > > I have a design for a good but relatively inexpensive (ca. > > > > $500 parts for three components) strong-motion sensor. > > > > > > This is excellent. Thank you for the information. > > > > > > I took a look at the report and component listing, and it > > > looks really interesting. But I am wondering how hard it > > > will be to source parts in single quantities, and also > > > the production of the PCB board would be very difficult > > > for me. I am very interested in getting a strong motion > > > sensor set up like the one you outlined, and the cost is > > > not a problem. But do I have to build it from scratch? > > > Any ideas on how I might get an assembled one, or at > > > least a PCB board for it? It appears to be exactly what > > > I am looking for but I'm a software guy and I'm not sure > > > I'm up to the task of putting it together from scratch. > > > Any ideas or suggestions? I'd sure like to try hooking > > > up ethernet to this 3028-based sensor. > > > > > > > You will need four channels (the fourth for temperature) > > > > if you use it. > > > > > > Is that three ICS-3028s and one thermistor? > > > > > > > PEPP would be interesting and useful too (Susan Schwartz at > > > > UCSC would like some teleseismic records, I'm sure, to look > > > > at anisotropy) but strong-motion is my passion (and bias!). > > > > > > I am very interested in the PEPP system also, and intend > > > to get one. Strangely though I can't seem to get a reply > > > from the people at Guralp. I sent two emails to their > > > north american sales rep asking for pricing and how to > > > order, but no reply so far. Any idea who I might talk to > > > to get one the CMG-PEPP units? > > > > > > Thanks, > > > Doug > > > > > > PS. It would be really interesting to put together a fairly > > > low cost yet useful strong motion sensor that could be > > > plug-and-play on the internet, automatically joining a > > > "federation" of other sensors. It would be cool to > > > have a station that anyone can use, with software that > > > automatically sends event data to a site on the net > > > that USGS could use for analysis. One could imagine > > > 1000s of these sensors plugged into everyday networks > > > all around the san andreas, imagine how much data > > > could be gathered! > The (single vertical component) Guralp PEPPVb instrument was done by Cansun > himself, and Steve Pauly was left out of the loop. We are not certain whether > they will continue to offer these instruments. > > Now that we are funded, we are trying to pull together an information base > on all possible instruments for high school use. This will include tricky > stuff like, can I order in quantity 1? is the instrumnet design stable? > what is its noise?. Almost all of the newer digitizer/data logger designs > for a PC permit several channels of input/display. So i assume that a strong > motion channel would be an excellent extension of the basic instrument. > > As you might suspect, established players in the CA seismic network business > feel swamped by their present stations, and have given us little indication > of wanting to add lots of additional stations with poorer S/N and dubious > maintenance problems. However, by adding a strong mkotion instrument, things > might change quickly. All of those SM instruments would serve a big public > need. > > Re: California. At present, there are stirrings from teachers in CA who > would like to run a seismic station. We hope to structure some "How to > get started" material, which will include encouragement for teachers to > form into local networks of 2-? under the auspices of a local college/univ. > > -- > Robert A. Phinney > Dept. of Geosciences > Princeton University > Princeton, NJ 08544-1003 > 609-258-4118 (ph) 609-258-1274 (f) > rphinney@............. [new on 23 June]. -- 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) Subject: Y2K From: John Lahr lahr@................... Date: Thu, 9 Sep 1999 11:00:07 -0600 (MDT) There may be some useful Y2K information on this site, per a USGS memo I received today. "... On the occasion of 9/9/99, we have prepared a web site ( http://9999.cr.usgs.gov ) with links to some of the more useful information on Y2K..." I'm not sure this is a public site, as I'm at work right now. I hope it is. JCLahr _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: PSN - Y2K Cards? From: Greg ghost@............. Date: Thu, 09 Sep 1999 10:24:48 -0700 "Rex Klopfenstein, Jr" wrote: > I am trying to decide to upgrade the motherboard or install a Y2K card You could get a used Pentium for that price, but there is no guarantee of Y2K with used. My mom's old P90 is more Y2K compatible than my P166 or my dad's P133 though. I've heard people talking about some $50-70 motherboards as "good", but that doesn't include the CPU or RAM or AGP video card. Also most newer motherboards are ATX size, and most 486s are AT. So you need a new case also. It's a bit tricky, but this is the way I look at it. You're going to be using DOS or DOS mode after Y2K right? DOS isn't really Y2K safe. Windows 95 isn't totally either. Try your computer right now, if it still works with the year set to 2000 or 00, then it will work the same then. The only problem you will have is the rollover from 99 to 00. Change the year on the clock at 12:01 AM. I found a 286 laptop that will work up to 2030. I can't imagine it being used then. If it still bothers you get a new computer. Most new motherboards and computers come with some kind of compliance testing statement. That doesn't include the operating system for most of them. I personally will be using non-Y2K compliant computers until I get a fair salary or win the lottery. All in fun, Greg _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Y2K From: Canie Brooks canie@........... Date: Thu, 09 Sep 1999 10:35:53 -0700 At 11:00 AM 9/9/99 -0600, you wrote: >There may be some useful Y2K information on this site, per a USGS >memo I received today. > >"... On the occasion of 9/9/99, we have >prepared a web site ( http://9999.cr.usgs.gov ) with links to some of the >more useful information on Y2K..." > >I'm not sure this is a public site, as I'm at work right now. I hope >it is. > >JCLahr I get a 403 Forbidden Error when I try to access the page - its available, just no permissions to see it. Canie _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Y2K From: John Lahr lahr@................... Date: Thu, 9 Sep 1999 11:45:15 -0600 (MDT) Woops, it was an internal site! Here's what's on it. JCLahr Y2K and YOU: A Site Dedicated to Providing Information on Y2K This site is being made available for employees who may have concerns about Y2K issues outside of the office. The U.S. Geological Survey has been working very hard to resolve mission and support problems, but many employees are not directly involved in that effort. The following sites represent the many great places to find information about Y2K topics that may impact us in our daily lives. The list is not intended to be complete, rather it is a good starting point from which you can begin your own searches. Information contained in the sites provided has not been reviewed for accuracy or endorsed by the USGS. Significant Dates for Y2K and Beyond http://www.r1.fws.gov/y2k/sigdates.htm Household Products and Consumer Update Information http://www.washingtonpost.com/wp-srv/washtech/longterm/y2k/consumer.htm http://www.ftc.gov/bcp/conline/edcams/y2k/index.html Banking http://www.fdic.gov/about/y2k/brochure/ Public Service Utility Company http://www.psco.com/y2k/default.htm US West http://www.uswest.com/about/year2000/ Local Community Information Sample sites--Contact your local city and county for specific information http://co.jefferson.co.us/y2k/y2kindex.htm http://www.ci.lakewood.co.us/y2k/y2k4.htm State of Colorado http://www.state.co.us/y2k Federal Government http://www.y2k.gov http://www.itpolicy.gsa.gov/mks/yr2000/y2khome.htm U.S. Geological Survey, PO Box 25046, Mail Stop 801, Denver CO 80225 URL: http://9999.cr.usgs.gov/index.htm For content information, contact: 9999 Page Created:September 1, 1999 Last updated: Wed Sep 08 15:09:38 1999 ... Site has changed since last visit! _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Flexures---YES From: The Gladow Family glad@.......... Date: Thu, 09 Sep 1999 14:38:30 -0500 A voice from the past has arisen; hopefully, it can be of some benefit to you guys. I recently happened to stumble across my name in your seismicnet-psnl site--- in a Charles Patton message back in March. It, and several other messages on this site, have brought the memories flooding back. As you might gather, I am semi-retired, doing consulting work only. However, my past experience--- especially at Sandia Labs (including design of unattended seismic stations), Rolamite/Foothill Inc. ("inventor-engineer" was the most fun position of my career), and Sparton Southwest (geophones and pressure instrumentation)--- might qualify me to make a few comments on flexural suspension systems. I've long been a "champion" of flexures--- a paradox of simplicity, and likely the least well known, yet most relied upon, mechanical element. Consider a few "elegant" (i.e., simple but highly effective) examples--- steel tape measures (where both the "blade" and retracting element are flexures), spring washers (common lock washer to Belleville), leaf springs (including the one in that stapler on your desk), paper clips (common and "binder"), and 3-ring binders (ever take one apart to what creates the action?). A few comments which might be of benefit: 1. Yes, spring metal flexures should definitely be the suspension of choice in seismic instruments (rather than bearings, hinges, knife edges, etc.). They can provide zero friction, insensitivity to dirt, zero lubrication, zero "dead zone", negligible hysteresis, and indefinite life with no degradation. They can also provide the centering force for the "zero position" and, if desired, an electrical path without dangling wires. 2. I agree with the consensus that the rolamite, which includes rollers as well as the flexural element, is NOT the suspension of choice. Basically, the rolling action, although very low friction, is susceptible to minor variations on the contacting surfaaces (contaminants, scratches, etc.) which become critical on the typically tiny motions of seismometer pivots. Alas, once again, the knock on rolamite of being "the second-best answer to anything" has arisen! Incidentally, although I have some rolamite-related patents, I am not the inventor of the basic device; that was the late Donald Wilkes. 3. The "crossed-flexure" design certainly has a lot going for it, since it can provide a very stable suspension as well as an "exact" center of rotation. For those designing devices which will go into production, the Bendix Free-Flex flexural pivot is an excellent choice--- I see from other messages that Lucas is now the manufacturer and/or distributor. However, for those building one-of-a-kind devices, a less expensive but more time-consuming solution is to do it yourself. I'm not familiar with the "Cardan hinge", but your descriptions indicate to me that it is also a crossed-flexure, utilizing a more complex flexure (band) which provides simpler assembly. 4. One possible exception to the choice of a crossed-flexure is the "inverted pendulum", which can provide a long-period instrument in a very compact package. (I've had lab setups of 20-second periods.) Yes, the crossed-flexure could work here also, but it would be difficult to do the final, precise "free-length" adjustment which is normally required. 5. As you can see from the above items, I generally agree with the inputs and conclusions of B. Nordgren and S-T Morrissey--- "taut" vs. "taught" not withstanding! :) Keep up the good work and analyses, guys. 6. The material from which flexures are made can be important. I used the term "spring metal flexure" above because this is normally what you want. Do NOT be tempted by the ease of plastics; you'll eventually be disappointed by hysteresis, "cold flow", and other degradations. To a lesser extent, soft metals (such as brass shim stock) have similar problems, and are relatively easily damaged. Spring steels are fine if corrosion is controlled. For flexure applications that "work hard" (large deflections and/or large forces), beryllium copper is typically the best choice, due to a high material effectiveness ratio--- allowable stress divided by elastic modulus--- and good fatigue life. However, this is normally unimportant for the minute motions of seismic devices. BeCu also has the advantage of being readily formed via photochemical machining (etching) into intricate two-dimensional shapes. 7. For anyone wanting to pursue the design of flexures in more detail, there is an unfortunate lack of textbooks, or even technical papers. By far the best book I've encountered (chock full of formuli, graphs, and tables) on the subject is Elastic Elements of Instruments by L. E. Andreeva. It was originally published in Russian, but was translated into English by the Israelis (IPST Cat. No. 2152). It can probably be found only in top-notch technical libraries. I do have a small collection of technical papers, including those published when rolamite was "hot". For anyone who feels that further input from me might be of some value, I'll plan on monitoring this site for a few weeks. After that, contact me via my E-mail address. Think flexures! ---Dean E. Gladow--- _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Y2K From: meredith lamb mlamb1@.......... Date: Thu, 09 Sep 1999 10:45:40 +0000 John Lahr wrote: > There may be some useful Y2K information on this site, per a USGS > memo I received today. > > "... On the occasion of 9/9/99, we have > prepared a web site ( http://9999.cr.usgs.gov ) with links to some of the > more useful information on Y2K..." > > I'm not sure this is a public site, as I'm at work right now. I hope > it is. > > JCLahr > Hi John, Apparently it is not....it shows "403 forbidden", no access to this computer....at least per my computer attempt. Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: TURKEY: Re: Strong motion for Santa Cruz mountain home From: meredith lamb mlamb1@.......... Date: Thu, 09 Sep 1999 12:00:14 +0000 Edward Cranswick wrote: > PSN and others- > There is a large number of people in Turkey at right now -- several tens of > millions -- who are in an excited state because of the Izmet Earthquake > , and many would be interested in having some > kind of seismograph to monitor weak/strong ground motions. I saw more cell-phones > in Istanbul than I have seen anywhere else; the populace is definitely hardware > conscious. The only thing they don't have is a cheap, reliable seismic data > acquisition unit built in the same mode as a PC computer; you take it out of the > box, plug it in, and it starts working. Something like a Kinemetrics K2, but an > order-of-magnitude cheaper, i.e., less than a $1000. > So the interest is there; where is the device? > -Edward Hi Edward, Glad you're back safely from Turkey and that disastrous quake and environment. Personally, I would think it was the toughest job of any USGS personnel, for the time involved. Probably a minimum of 16 hour days while you were there would also be a rough guess of a typical day. (The below is for anyones response) Anyway.....the one thing that kind of bothers me in understanding of the basic sensors variety is;.. why is their so much headlong ties with solid state type accelerometers, when specifically, the Hall device can do the same job? I understand solid state accelerometers in themselves would probably take up alot less physical space, while any Hall design would involve probably more space volume, i.e., added boom/mass and some kind of damping/feedback circuitry, or additional eddy current magnets approaches. Additional comparisons involve circuitry. I've seen Mr. John R. Evans circuit last year. It has alot of individual parts and alot of them involve nonstandard values. The Hall circuit (devoloped by Robert Lamb) I've used for over a year, has very few. Not withstanding some kind of damping mechanism, which could be eddy current also, let alone the possiblity of other electronic means. I always feel that the previous history of Hall devices has been "limited" by previous extensive research available on the web. These devices all used just standard 2 pole magnets in various configurations. Specifically, when 4 pole magnets are involved, the magnitude of sensitivity, bi-direction, velocity all improve dramatically...but I admit the circuit I use "overdrives" the Hall devices considerably, from the original design standard per gauss field....around 500, and not, 13-14K at or near the junction of the 4 pole magnets divisions. I suspect the linearity is affected somewhat, but I would think it wouldn't matter excessively. On the other hand, no Hall has failed electronically either. A rough comparison of my Hall devices with my old Sprengnether coil/magnet computer output shows a fair similarity, but, the coil magnets seem to win with distances over afew thousand miles from the epicenter of quakes. The likely difference is that the Hall are connected to a simple hanging pendulum (S-G design), whereas the coil magnet seismometers are amplified mechanically per their boom tilt angle with seismic signal arrival. I admit I'am bypassing the standard coil/magnet sensors in much discussion here. For amateurs, coils and magnets appropriation is difficult, whereas, Hall sensors are available (even at Radio Shack, on special order). I admit I lack alot of electronics knowledge, and educational background to go into much detail on specifics, but I hope that someone can explain the difference and the why-fors reasonably. I understand the added complexity of creating mini-seismos to fit Hall sensors over that of ready made accelerometers, but I would think its readily possible to do just that. Other thoughts especially with commercial companys, is that possibly they are "tied up" into standard approaches, and any new means involves expenditures they may not want to get into. Also, the idea of alot of manufacturing is too just shove the product "out the door", for profit, regardless of quality control....good basic idea....bad product.... On the other hand, if its just a seismometer for private curiosity, I would think that any people interested, could derive some benefit from using Hall devices. Any more extensive calibration involving knowledable engineering would likely have to be done by volunteers or any commercial interprise pursuing it. Perhaps the worst aspect of using Hall sensors, is the need for 4 pole magnet/s (one can use one or two, per each sensor). All of my sources have been surplus outlets. Alot of the thinner 4 pole magnets are difficult to remove from their original assemblys. Whether or not, commercial 4 pole pieces are still available now, is an unknown. For more Hall sensor details, visit the following web site: http://www.geocities.com/ResearchTriangle/Facility/1739/index.html Am looking forward to any replys,...I try to stay open to thoughts ........really.....ha. Thanks, Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Flexures---YES From: Karl Cunningham karlc@....... Date: Thu, 09 Sep 1999 15:52:26 -0700 Hi Dean -- Thanks for the report on flexures. After trying a pivot point, I'm now sold on flexures. One thing that bothers me is the possibility of oil canning. I don't think it is likely for a flexure to be free from this at microscopic scales, when operated near zero strain. I haven't seen a treatise on this but have noticed it in my experiments. A possible solution may be to not let the flexures go through zero strain, but I'm not sure. A positive aspect is that when operated in a seismometer with active feedback such as the VBB system, the change in stress during operation is minimal. Another potential source of hysteresis is the clamping at the ends of the flexures. If the clamping force applied and the friction aren't enough, the outer fibers of the flexure will slip under the clamp. This would dictate that the clamping be done far enough away from the bending zone that the stress in the flexure at the clamp will be low. Adhesives would be much simpler than mechanical clamps, but the potential for hysteresis due to cold flow seems much greater. I have been experimenting with full-hard 0.003" thick 304 stainless shim stock for flexures. I would like to etch the flexures out of the shim stock, as this would reduce the stress imparted during cutting. Do you have any comments about these two problems or my choice of material? Best regards, Karl Cunningham La Mesa, CA. PSN station #40 karlc@....... _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Utah rocking and rolling... From: Larry Cochrane cochrane@.............. Date: Thu, 09 Sep 1999 18:12:03 -0700 From the USGS finger service: 99/09/09 09:44:20 38.85N 111.98W 4.1 3.1Ml UTAH 99/09/09 10:07:41 38.85N 111.98W 4.5 3.6Ml UTAH 99/09/09 10:14:15 38.86N 111.97W 3.4 3.5Ml UTAH 99/09/09 11:38:43 38.86N 111.98W 4.0 3.6Ml UTAH 99/09/09 19:34:12 38.84N 111.98W 3.9 3.1Ml UTAH Keeping the phrase "be careful what you ask for" in mind, it would be nice to have one of these "calbration" events here so I can check out my new 1 hz sensor. -Larry Cochrane Redwood City, PSN _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: GPS location From: twleiper@........ Date: Thu, 9 Sep 1999 22:48:53 -0400 Is it just me? If I live west of the fault line, wouldn't I want the GPS point on the fault line due EAST of me? Or perhaps he really wanted people who were between 25,005 and 25,010 miles EAST of the fault line. Brothers and sisters, I have none, but that man's father is my father's son... On Wed, 08 Sep 1999 22:57:05 -0500 EK writes: >Dear seismic net ; > S.O.D.A.T. is looking for VOLUNTEERS to test a new Earthquake >Precursor Monitor System. What we are looking for is people that live >no >closer than 5 miles, but not over 10 miles west of a fault line. > To volunteer we need to now your GPS location and the GPS >point >due west of you on the fault line. You will also need to E-mail us at >any change on the GVR units, along with the time of the action. > For more information go to; >www.geocities.com/CapeCanaveral/Hall/1110/earthquake.html > > > Maj. Edward E. Kerls A.R. > > >_____________________________________________________________________ > >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) Subject: Re: PSN - Y2K Cards? From: barry lotz gbl@....... Date: Thu, 09 Sep 1999 20:13:47 -0700 Hi Rex JDR microdevices has one for $50. www.jdr.com (8 bit ISA) . They're in San Jose Calif. I don't have one but thinking of getting one. Since networking discussions came up, JDR also has a network starter kit for $90- $150. It has three cards,one hub, 25' cables, and drivers. Since I know little about networking I thought it would be good for me. Barry Rex Klopfenstein, Jr wrote: > I am trying to decide to upgrade the motherboard or install a Y2K card > in my SDR (486/66) computer. Can anybody point me to a source of a > cheap Y2K card. I have seen a few for around $90, at that price I'll > look for a cheap Pentum motherboard! > > Thanks in advance > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: GPS location From: EK kerls@...... Date: Thu, 09 Sep 1999 22:58:57 -0500 Yes your are right about the GPS point due east of you.. Sorry; but we of S.O.D.A.T. are bad spellers and typest, that is why we are S.O.D.A.T. [ The Society of Dyslexic Analytical Thinkers. ] Maj. Edward E. Kerls twleiper@........ wrote: > Is it just me? If I live west of the fault line, wouldn't I want the GPS > point on the fault line due EAST of me? > Or perhaps he really wanted people who were between 25,005 and 25,010 > miles EAST of the fault line. > Brothers and sisters, I have none, but that man's father is my father's > son... > > On Wed, 08 Sep 1999 22:57:05 -0500 EK writes: > >Dear seismic net ; > > S.O.D.A.T. is looking for VOLUNTEERS to test a new Earthquake > >Precursor Monitor System. What we are looking for is people that live > >no > >closer than 5 miles, but not over 10 miles west of a fault line. > > To volunteer we need to now your GPS location and the GPS > >point > >due west of you on the fault line. You will also need to E-mail us at > >any change on the GVR units, along with the time of the action. > > For more information go to; > >www.geocities.com/CapeCanaveral/Hall/1110/earthquake.html > > > > > > Maj. Edward E. Kerls A.R. > > > > > >_____________________________________________________________________ > > > >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) Subject: Re: GPS location From: EK kerls@...... Date: Thu, 09 Sep 1999 23:12:56 -0500 PS ; We of S.O.D.A.T. just thought that those of you that fit our GPS locations would like to monitor the Precursors of and Earthquake along with the Event and the after Events. Sorry that we bother you and your after the fact net. EK wrote: > Dear Mr. Cochrane; > In short, the Earth's core has been found to rotate about two degrees > faster, [ or about 0.36 miles per hour] than the Earth's crust. And sence the > core is where gravity comes from, thus gravity cuts across the crust at that > rate. But the core is not smooth , it has peeks and valleys just like the > surface does. It is theses wave forms that we are looking for because a valley > would lower the density level of gravity that is rising to the fault line that > is holding it in place.. This allows the westword movement of the plates to > move. > Of course you would want to detect these waves before they get to the > fault line. This is why you need to be to the west of the fault line for a good > waring time. > Maj. Edward E. Kerls A.R. > > Larry Cochrane wrote: > > > Edward, > > > > OK, I'll bite... I live about 5 to 10 miles from the San Andreas fault, but > > I'm east of the fault. What's the difference and why the narrow distance??? > > > > -Larry Cochrane > > Redwood City, PSN > > > > At 10:57 PM 9/8/99 -0500, you wrote: > > >Dear seismic net ; > > > S.O.D.A.T. is looking for VOLUNTEERS to test a new Earthquake > > >Precursor Monitor System. What we are looking for is people that live no > > >closer than 5 miles, but not over 10 miles west of a fault line. > > > To volunteer we need to now your GPS location and the GPS point > > >due west of you on the fault line. You will also need to E-mail us at > > >any change on the GVR units, along with the time of the action. > > > For more information go to; > > >www.geocities.com/CapeCanaveral/Hall/1110/earthquake.html > > > > > > > > > Maj. Edward E. Kerls A.R. > > > > _____________________________________________________________________ > > > > 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) Subject: Re: GPS location From: "Erich Kern" ekern@......... Date: Thu, 9 Sep 1999 21:22:44 -0700 Wait a minute. Kerls didn't say he wanted the GPS point of the fault, he wants YOUR GPS point, not the point of the fault nearest you. Kerls says "people that live ........west of of a fault line. What could be clearer than that? Erich Kern -----Original Message----- From: EK To: PSN-L Mailing List Date: Thursday, September 09, 1999 9:01 PM Subject: Re: GPS location Yes your are right about the GPS point due east of you.. Sorry; but we of S.O.D.A.T. are bad spellers and typest, that is why we are S.O.D.A.T. [ The Society of Dyslexic Analytical Thinkers. ] Maj. Edward E. Kerls twleiper@........ wrote: > Is it just me? If I live west of the fault line, wouldn't I want the GPS > point on the fault line due EAST of me? > Or perhaps he really wanted people who were between 25,005 and 25,010 > miles EAST of the fault line. > Brothers and sisters, I have none, but that man's father is my father's > son... > > On Wed, 08 Sep 1999 22:57:05 -0500 EK writes: > >Dear seismic net ; > > S.O.D.A.T. is looking for VOLUNTEERS to test a new Earthquake > >Precursor Monitor System. What we are looking for is people that live > >no > >closer than 5 miles, but not over 10 miles west of a fault line. > > To volunteer we need to now your GPS location and the GPS > >point > >due west of you on the fault line. You will also need to E-mail us at > >any change on the GVR units, along with the time of the action. > > For more information go to; > >www.geocities.com/CapeCanaveral/Hall/1110/earthquake.html > > > > > > Maj. Edward E. Kerls A.R. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: GPS location From: Norman Davis WB6SHI normd@............. Date: Fri, 10 Sep 1999 06:39:00 -0700 I am in the Sierra and there are all kind of minor faults up hear. What fault is he looking for. >Dear Mr. Cochrane; > In short, the Earth's core has been found to rotate about two degrees >faster, [ or about 0.36 miles per hour] than the Earth's crust. And sence the >core is where gravity comes from, thus gravity cuts across the crust at that >rate. But the core is not smooth , it has peeks and valleys just like the >surface does. It is theses wave forms that we are looking for because a valley >would lower the density level of gravity that is rising to the fault line that >is holding it in place.. This allows the westword movement of the plates to >move. > Of course you would want to detect these waves before they get to the >fault line. This is why you need to be to the west of the fault line for a good >waring time. > Maj. Edward E. Kerls A.R. > >Larry Cochrane wrote: > >> Edward, >> >> OK, I'll bite... I live about 5 to 10 miles from the San Andreas fault, but >> I'm east of the fault. What's the difference and why the narrow distance??? >> >> -Larry Cochrane >> Redwood City, PSN >> >> At 10:57 PM 9/8/99 -0500, you wrote: >> >Dear seismic net ; >> > S.O.D.A.T. is looking for VOLUNTEERS to test a new Earthquake >> >Precursor Monitor System. What we are looking for is people that live no >> >closer than 5 miles, but not over 10 miles west of a fault line. >> > To volunteer we need to now your GPS location and the GPS point >> >due west of you on the fault line. You will also need to E-mail us at >> >any change on the GVR units, along with the time of the action. >> > For more information go to; >> >www.geocities.com/CapeCanaveral/Hall/1110/earthquake.html >> > >> > >> > Maj. Edward E. Kerls A.R. >> >> _____________________________________________________________________ >> >> 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 > > Norman M. Davis WB6SHI Shingle springs, CA mailto:normd@............. http://www.directcon.net/normd/index.htm ICQ: 7192318 _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: INTEGRATED DATA From: "Francesco" franuc@...... Date: Fri, 10 Sep 1999 17:44:55 +0200 Someone can explain me the function of "INTEGRATED DATA" on Winaquake, = the reading and the interpretation of his? Francesco
Someone can explain me the function of = "INTEGRATED=20 DATA" on Winaquake, the reading and the interpretation of = his?
 
Francesco
Subject: Re: GPS location From: Stephen & Kathy mortskm@....... Date: Fri, 10 Sep 1999 09:13:06 -0700 E K, I would be interested in learning more about the Gravity wave sensor! I'm also in the foothills and east of the San andraes, but detecting gravity waves after the fact might be a good way to establish evidence for setting up sensors on the west side of the fault! At any rate it would be interesting to use the data from a line of sensors to try and determine the shape and motion of the core! I'm interested in anything that can be related to the cause or precursors of earthquakes! So, if you would,, I'm looking forward to any tech. info. you are willing to share. I might be interested in buying or building my own sensor. Stephen near Pilot Hill Ca 38.828N 120.9784W _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Geophone group buy - Last call.... From: Terence Dowling dowling@......... Date: Fri, 10 Sep 1999 14:39:34 -0700 I've been out of town so I'm lat getting back to you. If I've missed the window I'll completely understand. I have one of your amplifiers and I've already sent you a check for a 1hz geophone. Here is my question/quandry: I think I need an amplifier board? and If I'm going to do this, it seems to make sense to fill the available channels with a N-S and an E-W 4.5 hz geophones. If I'm making any sense, let me know what size $$ check I should write. If not, have patience with me and put me on the right path. I'll be back to my e-mail by Monday night (9/13). Thanks Terry Larry Cochrane wrote: > > All, > > Heres an update on the PSN geophone group buy. Last night I sent out a > series of emails informing everyone of the status of their order. I ended > up splitting up the order. I got about 1/2 of checks right away, so I ask > Jim at Mitcham if it was ok to order some now and then place another order > when I get the rest of the checks in. I currently wafting for this group of > sensors too arrive. > > So there is still time if anyone is interested. I currently have two checks > in house and am waiting for 4 or 5 more to come in. I want to get this over > with, so I think I will set a cut off date of mid next week or around Sept > 15. At that time I will place the second and last order (for awhile) with > Mitcham. Any checks received after the cut off date will be returned. > > This is the message I sent out list month about the group buy. Please note > that the sensors are used.... > > It looks like the final cost for the sensors will be $295.00 for the 1 hz > device and $37.00 for the 4.5 hz sensor. These prices include the cost for > shipping the sensors from Texas to Redwood City, Ca, but not the cost to > ship the sensor to the user. I'm not sure what the weight is for the > sensors, or what type of box and packing material I will need, so its hard > to give an exact price. My guess is that for the 1 hz sensor shipping cost > will be around $15.00 to $20.00 to addressed in the US, more for out of the > country orders. Maybe a little less for orders here in California. For the > 4.5 hz device the shipping cost should be about 1/2 the price. > > Too get the ball rolling lets do this. If you ordered one 1 hz sensor and > you live in the US send me a check for $312.00. If you ordered one of the > 4.5 hz device send me a check for $45.00. If the shipping cost ends up > being a lot less or a lot more I will send you a refund or ask for more $. > If you ordered more then one sensor the shipping cost should be a little > less. I will contact you directly with a price. I will also contact you > directly if you live outside of the US. > > Please make your check out to me and send it too: > > Larry Cochrane > 24 Garden Street > Redwood City, Ca. USA > 94063 > > 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 -- Terence Dowling (408) 536-3856 Adobe Systems Inc. dowling@......... _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Geophone group buy - Last call.... From: Doug Crice dcrice@............ Date: Fri, 10 Sep 1999 14:54:00 -0700 Terence Dowling wrote: > > > If I'm going to do this, it seems to make sense to fill the > available channels with a N-S and an E-W 4.5 hz geophones. > I'm relatively certain that those 4.5 Hz geophones are "vertical" geophones and they won't work as horizontals. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Flexures---YES 2 From: The Gladow Family glad@.......... Date: Fri, 10 Sep 1999 23:12:13 -0500 In response to a couple of further inquiries that I've received at home, in addition to the one on-line from Karl Cunningham: Experimenting with flexures--- Some flat, good quality spring-tempered flexure material which is readily available in a range of thicknesses is feeler guages. Although typically available only in a single width (0.500 inch), feeler guage stock should at least allow you to make some "mock-ups" for experimentation to determine what you need for your final design. Go to your local auto supply store. All should have the complete feeler guage sets, which have several blades typically ranging in thickness from .0015 inch to .040 inch that pivot into the handle for storage. If you're lucky, the store may also have single "replacement" blades for sale--- possibly in longer lengths; ask, since the single blades may be a "back-room" item. (The replacement blades allow you to obtain multiple flexures of the same thickness without buying additional sets.) In any case, try to get a set which has relatively long blades and has a screw-type pivot for easy disassembly. Most sets have flat blades, but there is also the "tappet-style" which has an approximate 30 degree bend about 2/3 down it's length; this might be useful for certain mounting situations. In any case, a set should run about $4-$8. Although obviously a spring steel, and somewhat "stainless" (although magnetic), I don't know what the material designation is (and it may vary, depending on origin). However, the important material property in determining the spring constant (k) is the elastic modulus (E), and this is essentially the same for all steels. Thus, your experimental results will be "accurate" to within a few percent for any spring steel. BeCu, phosphor bronze, and the "exotics" (such as low-expansion, constant modulus materials which some "purists" may want for their final design) can obviously be "ratioed" from your test results--- see paragraph on "Calculations" below. Forming flexures--- If your flexure is going to be a simple, constant-width, constant-thickness strip, and you can obtain the material in that width and thickness, the only thing you'll need is a pair of household scissors! Not tin snips, not a sheet metal shear, not a guillotine paper cutter, and not your kid's super-dull school scissors. You'll find that any relatively thin (say less that .012 inch) metal can be cut well with with a good (sharp) pair of scissors, and that it actually cuts "cleaner" in the hardened (spring) state than when soft. You can probably also "get by" with scissor cuts in the "active" portion of the flexure (i.e., cutting to an exact width) if you carefully "stone" the cut edges to remove any burrs or distortions. If you want mounting holes, obviously the normal drill bit won't do the job on hardened metals; the three best answers are--- 1. drill first, harden (heat treat) second, 2. use a hardened punch and die (total diametral clearance no more than material thickness), or 3. chemical milling. For complex shapes, such as the "spider" suspensions in geophones or bands with internal cutouts (such as in the "Cardan hinge"?), photochemical milling (etching) is really the only way to go. Basically, this consists of coating the material with a photosensitive material, exposing it to light with a mask providing the desired pattern, and then spraying with etchant chemicals. As mentioned in the earlier message, BeCu is easily etched; stainless steels are difficult. If you do use photochemical processing, additional features--- such as holes, slots, mounting "ticks", etc. are easily incorporated. Mounting--- Usually, thin flexures are attached at both ends (one end on the stationary base, the other to the moving assembly) using clamp bars and machine screws. The clamp bars need to be sturdy (e.g., at least 1/4 inch thick steel for 1/2 inch wide flexures) to maintain good contact across the entire width, and the screws well tightened. Having at least one of the screws through a hole or slot in the flexure can be helpful (particularly on wider flexures), as are somewhat roughened surfaces on the mating parts. Karl asked about adhesives; my feeling is "only if proven necessary in addition to the clamping". Distortion and/or "oil-canning"--- My experience with this would indicate that there is a some other problem present--- lack of clamp bar (or one which isn't sturdy enough), flexure material which wasn't initially flat, unequal weight distribution during assembly, too thin flexures for the weight being supported, etc. Having said all of this, I do kinda' like Karl's thought of AVOIDING ZERO stress/strain on these seismic devices. In other words, since the motion is very small, why not provide a mounting such that the flexure never returns to being completely flat. One way of doing this with crossed flexures would be to have 90 degrees between flexures on one (stationary?) end, and somewhat more (or less)-- perhaps 100 degrees-- on the other. Thus, both flexures would have a small initial curvature--- say 5 degrees if both have the same thickness, width, and free length--- which is larger than the maximum instrument motion. I can't think of any reason why the crossed flexures wouldn't work equally well. Calculations--- To a first approximation, the (torsional) spring force, and thus the (torsional) spring constant, can be calculated for flat flexures (or ones with small curvatures) using the "cantilever beam with end loading" equations of Mechanics of Materials. (Note that you will probably want to use the "slope at end", since the normal action of a flexure is a pivot.) For those who would prefer to do it entirely experimentally, your rules of thumb are: Force is directly proportional to the cube of thickness (i.e., doubling the thickness multiplies the force by eight); force is directly proportional to flexure width; force is directly proportional to elastic modulus of the material (i.e., BeCu will produce approximately 62% of the force of spring steels), and force is inversely proportional to the square of the free length (i.e., a free length of 1/4 inch is four times as "stiff" as a free length of 1/2 inch). "Inverted Pendulum"--- As indicated in the earlier message, this is a (potential?) method of making a long period horizontal seismic instrument in a compact package. The principle can best be understood by clamping a flat flexure, such as a .004 inch thick feeler guage blade, in a vise such that it is vertical. At the upper (free) end, start adding weight (a small bolt, washers, and nuts in the pivot hole of the blade is a convenient method), keeping approximately equal weight on each side of the flexure). You'll note that as the weoght is increased, the natural frequency changes. If too much weight is added, it becomes "bistable", leaning one way or the other when at rest. However, with just the correct weight, it becomes a surprisingly long period device (several seconds per cycle). In my earlier message, I was somewhat discouraging about the practicality of replacing the single flexure with crossed flexures; further reflection on my part says that the final adjustment could be just as indicated here--- adjustment of the mass instead of the free length of the flexure(s)--- which would then allow crossed flexures of a predetermined spring constant to be used. ---Dean E. Gladow--- _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Flexures---YES 2 From: barry lotz gbl@....... Date: Fri, 10 Sep 1999 22:19:44 -0700 Dean A few of my thoughts, experiences and questions. I have used cross flexures in the VBB style sensor described by Sean Thomas. I experienced oil canning with parallel 0.001" steel stock but not as much with 0.005 phosphor bronze. I think what I was experiencing was the fact that the two parallel shims were not in the absolutely same plane. I think the idea of something other than 90 degrees would work well. I haven't calculated the moment of inertia of fine music wire vs flat stock but parallel music wires might prevent this phenomenom. With regards to flexural steel properties, have you any references or input relating to steel relaxation vs time under stress? The VBB sensor uses an ~ 0.018" strip bent in ~180 degrees for a vertical spring. I have needed to adjust the zero for several months before the deflection/relaxation slows down. Someone in an earlier message likened this to the slow relaxation of a piano wire under stress. I think this would be a similar mechanism. I would be interested in a possible relation between strain vs time at various stress levels. How sensitive might this be wrt different metals? Regards Barry _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: INTEGRATED DATA From: barry lotz gbl@....... Date: Fri, 10 Sep 1999 22:23:06 -0700 Francesco If one is measuring acceleration vs time , if you integrate this you will get velocity vs time. If you integrate velocity you will get displacement vs time. Barry .. Francesco wrote: > Someone can explain me the function of "INTEGRATED DATA" on Winaquake, > the reading and the interpretation of his? Francesco Francesco
    If one is measuring acceleration vs time , if you integrate this you will get velocity vs time. If you integrate velocity you will get displacement vs time.
Barry
.

Francesco wrote:

Someone can explain me the function of "INTEGRATED DATA" on Winaquake, the reading and the interpretation of his? Francesco
Subject: gravimetry From: S-T Morrissey sean@........... Date: Sat, 11 Sep 1999 00:24:13 -0500 (CDT) Regarding the idea of detecting gravitational variations prior to earthquakes: The gravitational force is an effect between two masses m1 and m2 separated by some distance r. For a large object, the center of mass of the objects is the reference distance. The idea that gravity comes "from the core" of the earth and "cuts across" some part of the surface is rather far fetched. This implies that the gravitational force is some sort of "beam", rather than the omnidirectional force that it is. The formula for the force (F = G*m1*m2/r^2, G = 6.67 x 10^-11 N*m^2/kg^2) has no directive components; it is simply between the two objects. A good reference for studies of the core-mantle-boundary (CMB) is: "Earth's Deep Interior", edited by D.J.Crossley; Gordon and Breach Science Publishers; ISBN 9056990322. (Dr. Crossley is the Chair of the Department of Earth and Atmospheric Sciences at St. Louis University. He is a specialist in superconducting gravimeter systems and in interpreting the data). The book contains 11 research papers on the CMB conditions, and how they are determined from geomagnetism, gravimetry, seismology, and geochemistry. It contains hundreds of references. Several papers estimate the velocity at the CMB, which is the rotation of the outer core with respect to the lower mantle across the transition zone called the D" layer. Velocities of 4 x 10^-4 m/sec or 0.15 degree/year result from the most recent models; converting this to more familiar rates results in a velocity of 0.009mph. RMS values range from 12.7 to 14.3 km/year (4.03 to 4.53 x10^-4 m/sec), depending on the theoretical model chosen. All the models and the math are very complex. The flow of the core surface is also spatially irregular in both rate and direction, with the favored model called a "tangentially geostrophic" flow ( in the paper by Whaler and Davis in the book). It is not difficult to expect that the CMB is a rather irregular surface. And if there are irregularities in the mass distribution, they will cause variations in the gravity vectors that involve them. But detecting them has not yet been possible, even with superconducting gravimeters with a resolution of 1 nanogal ( 10^-11 of g). Gravimeter data is recorded in micro-gals, (10^-8 of g) for historical reasons. I have been operating a quartz-spring recording gravimeter at SLU since 1969. The dominant output is the 12 to 24 hour lunar-solar tides at 50 to 300 microgals (ugals). Instrument drift is around 100 ugal/year. To detect smaller effects, these have to be removed, as well as barometric effects, ocean tide loading, etc. This can reduce the noise level to less han 1 ugal, where oscillations of the core that are excited by large earthquakes can be detected. The primary nutation of the outer core is 433 days. Roughness or texture of the CMB HAS been detected by tomographic studies using modern broadband data. But the resolution is still poor until the density of VBB stations is significantly increased. Modern VBB seismometers reliably record earth tides as well, with resolution at the ugal level. But since the gravitational effect of any texture at the CMB is not currently detectable at the 0.001ugal level, the effect is orders of magnitude less than the lunar-solar gravitational changes of 50 to 300 ugals that occurr daily. Some have proposed these forces as trigger mechanisms for earthquakes, but the numbers don't agree any better than random chance. Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: [Fwd: Strong motion for Santa Cruz mountain home] From: Edward Cranswick cranswick@........ Date: Fri, 10 Sep 1999 23:58:12 -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". I thought I would chime in on this issue, as a CA network operator. As Bob pointed out, we (in N CA) are swamped trying to maintain our existing network of stations on what staff we have left after the Reduction in Force a few years ago. In addition, adding in exotic instruments to a real-time network can be a very time consuming task, particularly when the data are intermittent, noisy, etc. In other words, if the value-added is small in relation to the effort, then I probably cannot be actively involved. In particular, I don't think we have a problem locating earthquakes in CA, except for the hinterlands. In well instrumented portions of the state, a few more traveltimes is unlikely to improve our locations significantly. Of course, the recent work on doublets using waveform correlations could change this picture. Where I see the value of these PSN stations is in strong motion data. There are several grey-literature papers documenting a need for 1000's of observations in a metropolitan area, and the PSN sites are potentially quite useful. I suspect most PSN operators would be more interested in running weak-motion sensors, as there is more to see, but with the improvements in sensor quality and ADC dynamic range, perhaps they can have the best of both worlds in an accelerometer. A few questions to the group (forgive my complete ignorance of the PSN): Does anyone know how many PSN operators exist, say, in the SF Bay region? My level of interest goes with the power of 10. Would it be reasonable to ask that the PSN work with, say, the Earthworm developers to transmit data via the Internet in a common format, so regional seismic network operators could limit the amount of software integration? Likewise, could we ask for some set of standards, so that we don't start importing data that corrupts instead of enhances our dataset? -David Subject: Re: Automatic E-mailed earthquake files. From: barry lotz gbl@....... Date: Sat, 11 Sep 1999 08:49:45 -0700 Arie I suppose you probably already thought of it but would it be possible to request ones own data from another location in an autodrm method? Barry _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Flexures-YES 2 From: ACole65464@....... Date: Sat, 11 Sep 1999 12:08:25 EDT To All, My 2 cents worth. I have been using flexures in my seismometer designs for 6 years now and would never think of using a pivot point configuration again. If you are the type who needs to prove to themselves which is the better, a piece of music wire or a piece of shim stock, for a flexible hinge try this simple experiment. Take a piece of your favorite size music wire (example ..010" diameter), cut it 1" long. Calculate its cross sectional area (example is .0000785 sq. "). Then cut a piece of .001" thick heat treated shim stock, length 1". Cut its width to have the same cross sectional area as the wire piece (example shim width = .078"). Clamp both pieces in a vice with about 1/2" of each protruding. Push on the free end of both pieces. You will instantly notice which piece flexes the easiest. The horizontal instruments that I have been making lately have .002" thick shims for flexures. The upper flexure is narrower than the lower one. The upper is in tension and the lower is in compression. The lower flexure's width should be such that it will not buckle under the weight of the pendulum. Minimize the width of the flexures to minimize the restoring force on the pendulum. An inverted pendulum needs flexures that have sufficient restoring force to center the pendulum, otherwise the pendulum will flop off to the side. To reduce any oil canning effect, make sure that the surfaces that the fexures are clamped to are really flat and aligned in the same plane. Don't clamp them directly to the surface of a piece of extruded aluminum (straight from the mill) for example. Place a straight edge across the mounting surfaces and hold it up to the light. Run the straight edge backwards and forwards to ensure some degree of flatness. If you cannot have the flexure mounting surfaces machined coplannar, put a piece of fine emery paper face up on a machined flat plate, then slide the part you want flat across the paper in a figure 8 pattern, without rocking the part. This should at least knock off the high spots. Having non-distorted, burr free edged flexures will not perform well if they are forced down on an uneven and/or misaligned surfaces. Thank you Dean for in depth description of flexures. Allan Coleman _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Automatic E-mailed earthquake files. From: TMrvos@....... Date: Sat, 11 Sep 1999 14:20:55 EDT HUH ??? _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: gravimetry From: EK kerls@...... Date: Sat, 11 Sep 1999 15:14:41 -0500 Dear S-T Morrissey ; I am sure you can state known theories over and over again. Because you was taught them as facts all though out your education.Yes, the math that you quoted does work , but the statement that it is simply forces between two objects is wrong. We download gigabytes of new facts daily, it is these facts that we are working with, not 50 year theories. Answer this. Why can't our 96 ton space shuttle can't attract even a human hair? Would you like to see these new facts, are not???? Maj. Edward E. Kerls A.R. S-T Morrissey wrote: > Regarding the idea of detecting gravitational variations prior > to earthquakes: > > The gravitational force is an effect between two masses m1 and m2 > separated by some distance r. For a large object, the center of mass > of the objects is the reference distance. The idea that gravity comes > "from the core" of the earth and "cuts across" some part of the surface > is rather far fetched. This implies that the gravitational force is > some sort of "beam", rather than the omnidirectional force that it is. > The formula for the force (F = G*m1*m2/r^2, G = 6.67 x 10^-11 N*m^2/kg^2) > has no directive components; it is simply between the two objects. > > A good reference for studies of the core-mantle-boundary (CMB) is: > > "Earth's Deep Interior", edited by D.J.Crossley; Gordon and Breach > Science Publishers; ISBN 9056990322. > > (Dr. Crossley is the Chair of the Department of Earth and Atmospheric > Sciences at St. Louis University. He is a specialist in superconducting > gravimeter systems and in interpreting the data). > > The book contains 11 research papers on the CMB conditions, and how > they are determined from geomagnetism, gravimetry, seismology, and > geochemistry. It contains hundreds of references. > > Several papers estimate the velocity at the CMB, which is the rotation > of the outer core with respect to the lower mantle across the transition > zone called the D" layer. Velocities of 4 x 10^-4 m/sec or 0.15 > degree/year result from the most recent models; converting this to > more familiar rates results in a velocity of 0.009mph. RMS values range > from 12.7 to 14.3 km/year (4.03 to 4.53 x10^-4 m/sec), depending on > the theoretical model chosen. All the models and the math are very complex. > The flow of the core surface is also spatially irregular in both rate > and direction, with the favored model called a "tangentially geostrophic" > flow ( in the paper by Whaler and Davis in the book). > > It is not difficult to expect that the CMB is a rather irregular surface. > And if there are irregularities in the mass distribution, they will cause > variations in the gravity vectors that involve them. But detecting them > has not yet been possible, even with superconducting gravimeters with a > resolution of 1 nanogal ( 10^-11 of g). > > Gravimeter data is recorded in micro-gals, (10^-8 of g) for historical > reasons. I have been operating a quartz-spring recording gravimeter at > SLU since 1969. The dominant output is the 12 to 24 hour lunar-solar > tides at 50 to 300 microgals (ugals). Instrument drift is around 100 > ugal/year. To detect smaller effects, these have to be removed, as well > as barometric effects, ocean tide loading, etc. This can reduce the > noise level to less han 1 ugal, where oscillations of the core that are > excited by large earthquakes can be detected. The primary nutation of the > outer core is 433 days. > > Roughness or texture of the CMB HAS been detected by tomographic studies > using modern broadband data. But the resolution is still poor until the > density of VBB stations is significantly increased. Modern VBB seismometers > reliably record earth tides as well, with resolution at the ugal level. > > But since the gravitational effect of any texture at the CMB is not > currently detectable at the 0.001ugal level, the effect is orders of > magnitude less than the lunar-solar gravitational changes of 50 to > 300 ugals that occurr daily. Some have proposed these forces as trigger > mechanisms for earthquakes, but the numbers don't agree any better than > random chance. > > 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 _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: more flexures From: S-T Morrissey sean@........... Date: Sat, 11 Sep 1999 15:46:12 -0500 (CDT) Regarding comments on hinge flexures: my 2cents: My experience is that things aren't that difficult: 1: Cutting the material: I bought a roll of 0.005" phosphor-bronze from McMaster, as well as stainless and spring-steel sheets. I have had no problem cutting the thinner material, up to 0.010", with an office type paper cutter. It makes very clean, burr-free, and straight cuts. I do sharpen the cutter (flat file the edges) once every few years. To make a single 1/4" hole in the thin material (for clearance of the single clamping screw) I use a common paper punch. Most will make a clean hole. 2: Gluing the flexures: industrial-strength, like DEVCON brand, epoxies are stronger than the hinge material IF the surfaces are properly cleaned and prepared. I "un-polish" the surfaces with 400-grit emery paper. The shear strength of these epoxies is remarkable; so under normal conditions they work well, since the forces on crossed-hinge flexures are entirely in shear. Glued flexures are the ultimate in a noise free (no micropositioning) design. The ones where I prepared the surfaces properly and haven' t abused have lasted many years and show no signs of coming apart. But the abused ones, where the flexure actually gets bent from such clever acts as dropping the seismometer, are a problem. The bent flexure starts to come unglued at the hinge side. So I have installed a single screw clamp thru a hole punched in the hinge strip to a tapped hole in the aluminum angle to control any accidental damage. I use a 1/4", 6-32 pan head screw, a #10 washer, and a 1/4" washer with the side toward the hinge filed straight. The straight edge is aligned exactly over the filed back corner edge of the aluminum angle. (figure needed!) (Excerpt from previous explanation: When I prepare the aluminum angle brackets that the hinges are epoxied to, I file off the outside corners of the angles in the area where the hinges go from one bracket to the other. I file the corner at a 45deg angle, removing about 1/16 or more from each orthogonal side, so when the hinges are assembled, the free air distance is at least 0.125 inches. The actual pivot point is within the hinge thickness (0.005") of the corner of the angles. This method of providing the hinge clearance has been common practice in many of the hinge designs I have seen in large mechanical seismometers over the years. ) When the flexure is visibly bent it has to be replaced. It can usually be pealed away from the aluminum angle and the epoxy sanded off. This usually means re-doing all the flexures of a hinge assembly; a clamping arrangement without gluing could avoid this. 3: I have had no problem in using extruded aluminum angle stock from hardware stores or McMaster supply. THe tolerances are very good. 4: I have had no indication of the "oil can" distortion. Even after cutting, the flexures are flat enough to mirror your face in. However, once a flat piece has been bent or twisted, it is history, since the original stress-free surface is lost. A handy source of thin brass sheet is the hobby materials section of your ACE hardware store. 5: Flat or crossed flexure hinges are generally not used in compression. In the case of a flat hinge, especially used as the lower hinge of a "garden gate" horizontal, this can result in unstable and non-linear response, since as the center of mass moves away from the centerline of the boom, the hinged end moves in the opposite direction (at the scale of the ground motions we are interested in .... microns or less). Large horizontal boom seismometers use a short taught wire for both upper and lower hinges, where its dimension is minimal compared with boom length and transducer clearance. More compact horizontals with close tolerance transducers use crossed hinges for both, with the flexure elements under tension (even when using the Lucas-Bendix assemblies).. In general, the spring constant of the hinges should be much less than the gravitational restoring force that determines the instrument characteristics. In fact, forces caused by the hinges are usually ignored, and the period of the horizontal is calculated by: (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 (like the SG design) 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 less stable also means sensitive to smaller ground motions. THen the tilt sensitivity of a horizontal is a function of the square of the operating period Tn. (where z is the displacement, and phi is the tilt) z = (g * Tn^2 / 4 * pi^2) * phi (horizontal) 6: Inverted pendulums have been experimented with since the Weichert of 1903. Even with a mass of 80 kg 1 meter above the hinge, the operating period was only 6 seconds. There was a "Reef" design that was about 1 meter high but was only usefully stable to 1 second. Horizontal-boom designs (as above) were preferred because their response does not depend on the elastic behavior of the hinge. Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: more flexures From: barry lotz gbl@....... Date: Sat, 11 Sep 1999 19:34:37 -0700 $0.02 I did the math: An 0.008" diameter music wire has the same moment of inertia as a 0.005" thick shim stock 0.3" wide. I use this wire in a FB horizontal with both hinges in tension and it works very well. Barry _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Automatic E-mailed earthquake files. From: Arie Verveer ajbv@............ Date: Sun, 12 Sep 1999 11:46:34 +0800 Hi, > HUH ??? This was general method that I used to send the raw data from my seismograph to my residence. The device is some 11 km away. For most P.S.N users it not really relevant but for anyone who has a remote station the technique may be useful. The original P.S.N message was on the 8/31/99. Arie _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Automatic E-mailed earthquake files. From: Mark Robinson other@............... Date: Sun, 12 Sep 1999 15:56:36 +1200 hi folks, is anyone streaming seismo data onto the net ? regards Mark _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Automatic E-mailed earthquake files. From: Larry Cochrane cochrane@.............. Date: Sat, 11 Sep 1999 23:59:13 -0700 Mark, See the Albuquerque Seismological Laboratory web site at http://aslwww.cr.usgs.gov/Seismic_Data/. I just placed a event file on my system from station TATO in Taiwan for the Mb 5.6 TAIWAN REGION event. I used the live data feed from ASL to create this event file. -Larry Cochrane Redwood City, PSN At 03:56 PM 9/12/99 +1200, you wrote: >hi folks, > >is anyone streaming seismo data onto the net ? > >regards >Mark > >_____________________________________________________________________ > >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) Subject: Re: Automatic E-mailed earthquake files. From: Mark Robinson other@............... Date: Sun, 12 Sep 1999 19:30:53 +1200 Thanks larry, that was easier than I expected, now I just need to learn enough to write a program to decode from a telnet session under windows ... or spend some more time getting the Linux system working :) I had seen the Liss before, but only as the graphical page, and I didn't realise it had the streaming function underlying it ... some damn strange patterns on there today. What is the story on the server software ? regards Mark Larry Cochrane wrote: > > Mark, > > See the Albuquerque Seismological Laboratory web site at > http://aslwww.cr.usgs.gov/Seismic_Data/. I just placed a event file on my > system from station TATO in Taiwan for the Mb 5.6 TAIWAN REGION event. I > used the live data feed from ASL to create this event file. > > -Larry Cochrane > Redwood City, PSN > > At 03:56 PM 9/12/99 +1200, you wrote: > >hi folks, > > > >is anyone streaming seismo data onto the net ? > > > >regards > >Mark > > > >_____________________________________________________________________ > > > >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) Subject: Frozen male mammoth found in Siberia From: meredith lamb mlamb1@.......... Date: Sun, 12 Sep 1999 10:51:10 +0000 Hi all, Yes, this has nothing to do with seismology...but its sure very, very interesting. Too exciting too me, to not share.... Haven't heard of this till today....a wolly male mammoth was found in 1997 in Siberia by natives. A french explorer by the name of Bernard Buiques was led to the site. A expedition seems to be underway to dig it out, transport it to a different site and begin examination. One of the main hopes is that the sperm or DNA can be used to clone another mammoth (mixed species), and so on, to get a majority of a resurrected mammoth over time. See the discovery web site: http://www.discovery.com/exp/mammoth/mammoth.html From there their is other clickable "pages" to look over....like weblink.html , clue.html, and especially the dispatch.html, with real photos at the site. The top picture is not real, where the tusks are sticking up out of the ground (although it was actually found by the natives like that). As for more coverage, a discovery channel employee, by the name of Dirk Hoogstra is leaving this Sept 12th, 1999, to cover the expedition; and hopefully more (much more) photos and details will be forthcoming soon thereafter. Have heard of Japanese attempts a year or so ago, with tusks being found, but no actual mammoth bodys being found. Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Frozen male mammoth found in Siberia From: "Anders Heerfordt" aheerfor@...... Date: Sun, 12 Sep 1999 19:03:09 +0200 > Haven't heard of this till today....a wolly male mammoth was found in 1997 in Siberia by natives. < A hundred years ago findings of mammoth were far more common than now, as far as I know. If eggs and sperm had been preserved in liquid nitrogen, the chances would have been much better of ressurecting the mammoth... I wish we knew what killed them. A large meteor hitting the earth 11000 years ago, or something else? Regards, Anders _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Frozen male mammoth found in Siberia From: meredithlamb@.............. Date: 12 Sep 1999 10:24:54 -0700 On Sun, 12 September 1999, "Anders Heerfordt" wrote: > > > > Haven't heard of this till today....a wolly male mammoth was > found in 1997 in Siberia by natives. > < > > A hundred years ago findings of mammoth were far more common than now, as far as > I know. If eggs and sperm had been preserved in liquid nitrogen, the chances > would have been much better of ressurecting the mammoth... > > I wish we knew what killed them. A large meteor hitting the earth 11000 years > ago, or something else? > > Regards, Anders > Anders, Yes, over time alot of carcasses have been found. Some stuffed, mounted etc, mainly by the Russians. Impression I seem to pick up is that the natives of Siberia, fairly infrequently come across these remains, but are more concerned with the money that the pieces and parts will bring in. Often, it seems, some are not reported either. On the other hand, if one was a native, this could be considered common place stuff, and without alot of the essentials common to alot of the world, they would disregard much excitement about it, (it doesn't put food on the table or present a value) otherwise, their life is extremely harsh normally anyway. Understand that some of the natives consider the bones/tusks with a superstition, relating to a long sleep, if one possess's them. The extinction of the species, and other animals, seems anymore to be tied up with either man himself and/or extreme rapid climate (and short term, like a decade) climate change from what I've heard or read. Probably really an open que stion...with no definite resolve forthcoming. Regards, Meredith Lamb Signup for your free USWEST.mail Email account http://www.uswestmail.net _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Material Creep From: The Gladow Family glad@.......... Date: Sun, 12 Sep 1999 13:02:58 -0500 To: Barry Lotz & other interested parties Hey, I hadn't expected to get this deeply involved in the details, but since you asked about "relaxation vs. time under stress" in the second paragraph of your September 10th message: 1. Basically, material creep is a primary reason that my initial message included the statement "Do NOT be tempted by the ease of plastics"--- since even the best engineering plastic will exhibit a creep rate which is typically a couple orders of magnitude worse than metals. 2. As you have discovered, however, even metals--- under continuous loads producing relatively high stress--- will exhibit some creep. This is not unique to flexures; you already pointed out that it can happen to music wire, and most of us have seen cases where coil springs have "relaxed" when under load for long periods. Even knife-edge pivots have been shown to have some (small) amount of "cold flow". 3. Therefore, there should be little, if any, concern about creep in flexures for "horizontal-boom" seismic devices, where the stress level is low. I am, however, a fan of using comparatively thicker spring-metal flexures, say in the .004 to .008 inch range for spring steels, for your typical size and weight instruments--- but this is primarily because of the ruggedness which is provided. For those, like Sean-Thomas, who want to maintain gravity as the primary centering force, you can readily compensate for flexure thickness by increasing the free-length (i.e., distance between clamps) per my "Calculations" paragraph of previous message. 4. But, back to your case of the "VBB sensor using an ~.018" strip bent in ~180 degrees". The stress level is obviously rather high, so what can be done?--- 5. As you have noted, creep is time dependent--- gradually decreasing over a period of months. Therefore, one helpful "trick" used by many instrument manufacturers is to speed up the "aging". A typical method of doing this is the cycle the metal (a minimum of 100 times, with 1000 being better) to a stress level which is approximately 50% higher than the load which will be seen in service. Obviously, you don't want to exceed the yield strength or proportional limit! Application of heat--- perhaps 250 degrees F, but again well below any temperature used for heat treatment (or normalizing) of that particular metal--- during the cycling will also assist in the stress aging. 6. Yes, the selection of the spring metal is also important in controlling creep. However, the metallurgists and other experts tend to use a lot of caveats--- items such as differing times and temperatures during tempering, amount of cold-working due to rolling or drawing to final size, etc. Therefore, I haven't seen any good comparisons in tabulated data. (Anyone else?) One general rule of thumb seems to be to avoid those spring metals which are hardened entirely, or primarily, by strain hardening ("cold working") rather than heat ("precipitation hardening" and "transformation hardening"). This would indicate the avoidance of phosphor and silicon bronzes, 18-8 stainless, and the 300 series of stainless steels if your application demands minimum creep. ---Dean E. Gladow--- _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Material Creep From: S-T Morrissey sean@........... Date: Sun, 12 Sep 1999 16:59:11 -0500 (CDT) A bit of historical info: For several decades the "zero-length" springs of long(ish) period seismometers with large (gt. 5kg) masses were shipped with a stretcher rod on the inside of the coil spring. (These seismometers are too large to be shipped with the mass and spring installed). The length was the working length of the spring, and although it was quite necessary just to get the spring installed, the main reason was to pre-stress the spring to minimize creep after the instrument was installed. The sensors still needed several days to stabilize. Newer VBB leaf-spring designs are "factory aged" before final determination of constants is done. Some are still notorious for needing a "settling in" period of several days to weeks every time they are installed. Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Frozen male mammoth found in Siberia From: GeE777@....... Date: Sun, 12 Sep 1999 20:33:22 EDT In a message dated 9/12/99 10:25:09 AM Pacific Daylight Time, meredithlamb@.............. writes: > The extinction of the species, and other animals, seems > anymore to be tied up with either man himself and/or > extreme rapid climate I have worked on seismic crews on the North Slope of Alaska. We found several half frozen mammoths. I had a tooth from a Mammoth for a long time but it got stolen from me. George Erich _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Frozen male mammoth found in Siberia From: meredithlamb@.............. Date: 12 Sep 1999 18:27:11 -0700 On Sun, 12 September 1999, GeE777@....... wrote: > > In a message dated 9/12/99 10:25:09 AM Pacific Daylight Time, > meredithlamb@.............. writes: > > > The extinction of the species, and other animals, seems > > anymore to be tied up with either man himself and/or > > extreme rapid climate > > I have worked on seismic crews on the North Slope of Alaska. We found > several half frozen mammoths. I had a tooth from a Mammoth for a long time > but it got stolen from me. > > George Erich Hey George.....would sure like to hear about that and/or any particular circumstance that stands in your memory. Where, who, etc. Real interesting circumstance I would think. I would suppose that previous to current DNA type advances that there wasn't much one could do with a carcass, for the time period you may be speaking of. Actually Sean-Thomas and John Lahr were also up in Alaska. Makes me wonder if they have storys also... whether being part of a find or hearing it from others? Thanks, Meredith Lamb P.S. I suppose that the British Columbia ice man story will eventually come out, that was also found recently. He was found entombed in a glacier, and maybe up to some 10 thousand years old. Think the specimen is in a Vancouver college at the moment. Personally, the only thing age doubtful about him was the hat. The hat looked like it had fine weaving...like it was much more recent. Spear, knif e, buckskin clothing, alot of intact flesh. Reported on Aug 25th 1999. Think CNN web news has the most comprehensive of any, at the moment. Signup for your free USWEST.mail Email account http://www.uswestmail.net _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Home Depot stores ferrite magnets From: meredithlamb@.............. Date: 12 Sep 1999 20:06:15 -0700 Hi all, Just a general note. I see Home Depot stores are now selling a limited variety of ferrite magnets. The particular Denver store where I went had some 3/8" X 7/8" X 1-7/8" rectangular blocks (stock #07044, made by "The Magnet Source"/Master Magnetics, Inc./Craft Magnets...all the same company). Mostly refrigerator round button sizes, but afew other block sizes. The size I got, just happened to fit in some square coils I've had for a long time. OK....loosely, but better than nothing...ha. Meredith Lamb Signup for your free USWEST.mail Email account http://www.uswestmail.net _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Aftershock in Izmit From: Oguzhan Aydogmus-HRB oaydogmus@................ Date: Mon, 13 Sep 1999 15:36:46 +0300 Place: Izmit Magnitude: 5.8 Date : 13.09.99 _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: R: Aftershock in Izmit From: "Francesco" franuc@...... Date: Mon, 13 Sep 1999 15:13:29 +0200 The same localization from italian stations. Ms 6.0 Good vaweform Francesco I.E.S.N. - PSN Italy _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Frozen male mammoth found in Siberia From: GeE777@....... Date: Mon, 13 Sep 1999 13:57:22 EDT In a message dated 9/12/99 6:27:30 PM Pacific Daylight Time, meredithlamb@.............. writes: > Hey George.....would sure like to hear about that and/or > any particular circumstance that stands in your memory. > Where, who, etc. Real interesting circumstance I would > think. The years I was up on the North Slope, North of the Brooks Range was 1950 and 1951. Once a short time after that. Every few weeks someone on the crew would come across a partially frozen and buried carcass of a mammoth. The tooth I found was in a dry wash, in an area of many rounded stones about the size of the tooth. It was on the west side of the Naval Petroleum Rreserve There was a Bison found further south by gold miners that was estimated to be 35,000 years old and claw marks indicate it was killed by a lion. (see Guthrie, Dale and Guthrie, Mary Lee "Death on the steepe: the case of the frozen bison" New Scientist No. 1727, 28 July 1990 p. 47-51) George Erich _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: PC-based seismograph From: Edward Cranswick cranswick@........ Date: Mon, 13 Sep 1999 12:07:55 -0600 Eric- Thank you for the information. Please notify me when the product is released. -Edward eric_canuteson@....... wrote: > Mel Lund forwarded your inquiry regarding a simple, low-cost seismograph system > for Turkey. We are now offering a PC-based seismograph for $495. The device is > a 1-channel system based on a geophone and intended primarily for educators and > hobbyists. The software is compatible with older computers (386 DOS) as well as > newer systems. The seismograph provides a graphical window that emulates a drum > recorder as well as data analysis and event recording. > > We are about 3 weeks away from receiving our first production shipment of these > devices, and the information will be available on the internet at that point. > > Sincerely, > > Eric Canuteson > Kinemetrics, Inc. -- 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) Subject: Re: PC-based seismograph From: Greg ghost@............. Date: Mon, 13 Sep 1999 22:36:23 -0700 Edward Cranswick forwarded: > > Mel Lund forwarded your inquiry regarding a simple, low-cost seismograph system > > for Turkey. We are now offering a PC-based seismograph for $495. The device is > > a 1-channel system based on a geophone and intended primarily for educators and A 1 channel geophone system for $500? I hope that's a better deal than what it sounds like. I didn't see it on their website yet. Maybe I missed it? Larry could probably set you up for about $300, based on that description. ,Greg _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: PC-based seismograph From: Doug Crice dcrice@............ Date: Tue, 14 Sep 1999 09:09:52 -0700 With all due respect, $500 for a single channel seismograph from a major company is sounds pretty reasonable for me, perhaps even a tactical error. Even though Larry can set you up with an equivalent or better system for $300, you should understand that he is subsidizing the PSN by taking a smaller salary than he deserves, probably dedicating part of his home rent free, and I would guess working unpaid overtime. However, he is filling a market niche, segmenting it to match his resources, a viable business strategy. Kinemetrics is paying rent, free-market salaries, employment taxes, benefits, marketing expenses, ISO documentation, and has to make a profit besides. The reason a $500 seismograph is probably a mistake for them is that it will eat up the same selling expenses (or more) than a $10,000 item. Somebody will have to talk to the customer, respond to an RFQ, write the order, ship the thing, and then answer those support inquiries. It's not like you can crate up a gross of these units and ship them to a distributor like a cell phone, they will have to sell them the old-fashioned way: one at a time. And how many are they going to sell over the lifetime of the product? 1000? 5000? $5000 x 500 is only $2.5 million dollars. For the same amount of engineering they could have designed something with a real revenue stream (although probably they are running out of things to invent). $500 gentlemen is a bargain. Kinemetrics would be smart to give the design to Larry and refer all enquiries to him. Larry, on the other hand, might consider a push into the education market. He could reach it within his budget, and might multiply his sales substantially. Greg wrote: > > Edward Cranswick forwarded: > > Mel Lund forwarded your inquiry regarding a simple, low-cost seismograph system > for Turkey. We are now offering a PC-based seismograph for $495. The device is >> a 1-channel system based on a geophone and intended primarily for educators and > > A 1 channel geophone system for $500? I hope that's a better deal than > what it sounds like. I didn't see it on their website yet. Maybe I > missed it? > > Larry could probably set you up for about $300, based on that > description. > > ,Greg -- 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) Subject: Re: PC-based seismograph From: GeE777@....... Date: Tue, 14 Sep 1999 12:21:03 EDT In a message dated 9/13/99 10:37:23 PM Pacific Daylight Time, ghost@............. writes: > The device is > > > a 1-channel system based on a geophone and intended primarily for > educator I am using a 3 channel PC based system George Erich _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: PC-based seismograph From: Greg ghost@............. Date: Tue, 14 Sep 1999 10:56:39 -0700 Doug Crice wrote: > With all due respect, $500 for a single channel seismograph from a major > company is sounds pretty reasonable for me, perhaps even a tactical > error. Even though Larry can set you up with an equivalent or better Larry runs this list. He runs the web site. He designed the hardware. He builds the hardware. He ships the hardware. He wrote the software. He does tech support. He's a great guy working for peanuts. Kinemetrics is some company trying to muscle in on Larry (to me). Then again they might have actually done something new for a low price and put a warranty on it? I don't know yet. > $500 gentlemen is a bargain. Kinemetrics would be smart to give the > design to Larry and refer all enquiries to him. Larry, on the other I'm anxious to see exactly what they "designed". My guess is very little. I'm a pessimist though, no doubt. A bargain to me is not easy for the seller at all. I'm not cheap, but I am poor. $500 without specs or details cannot be defined as a bargain. I'll sell you a car for $5,000. What a bargain! Wheels and tires are no charge. I've seen cars costing over $1,000,000. Just think of the savings you're getting. Suppose they spent the bare minimum to get it to work. What does that cost? Maybe $100 plus software and design. For all I know right now, they didn't design anything except software. A company is not the most admirable source of ethics these days. To blindly offer respect for one is sad. You probably know them better than I do. To me a company is just a bunch of people trying to make money. That's all I'm going to say until I see more from Kinemetrics, Greg _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: PC-based seismograph From: Doug Crice dcrice@............ Date: Tue, 14 Sep 1999 13:01:20 -0700 Greg wrote: > > A company is not the most admirable source of ethics these days. To > blindly offer respect for one is sad. You probably know them better than > I do. To me a company is just a bunch of people trying to make money. > I have known Kinemetrics for over 25 years. The founders Bob Swain, Harry Halvorson, Bill Rihn and Lee Benuska were among the most ethical people I ever dealt with both as vendors and customers. They taught me about fair dealing and showing respect for the customers, and about what it takes to run a business. Perhaps you can find big companies with practices you disagree with, but all of Geophysics and Seismology is a small family and you don't succeed, especially over the long run, by treating customers unfairly. To blindly criticize a company is sad. Another of my mentors taught me the definition of a fair price: "one that's high enough to allow you to stay in business and continue to serve your customer". By that definition, I would suggest that Larry's prices are too low, and are subsidized by his heroic efforts and love of the game. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: PS-2 Personal Seismograph From: S-T Morrissey sean@........... Date: Tue, 14 Sep 1999 17:43:47 -0500 (CDT) re: PS-2 Several years ago I evaluated a self-contaied short period "personal seismograph" called the "PS-2" , from a company called GEOSENSE in Pasedena. The single-channel price was $450 ( in 1995). It consisted of a package that plugged into a com port on a PC thru an adapter that also supplied power to the sensor package from a wall adapter. The sensor is a 4.5 hz geophone, aparently over damped for a broader response, and an 19-bit digitizer with a sample rate of 128 hz. Several programs ran on the DOS PC, including a "recorder" helical drum emulation mode and various analysis and plotting routines. The PC clock was used for time. The software included event detecting with a pre-event buffer for automatically saving files to disk in binary format. The files could be exported as an ascii table. The sensitivity was not great: The manual lists a threshold (LSB?) of 1.6 microns/second at 1hz and 76 nanometers/second from 4.5 to 32 hz. At one point the manual suggests jumping up and down to test the sensor. I don't know if this has anything to do with the recent discussion of a similar system from Kinemetrics. regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: PS-2 Personal Seismograph From: TMrvos@....... Date: Tue, 14 Sep 1999 18:47:23 EDT Where is the sensor located and how is it installed ? Any brochures available ? _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Microseisms from Hurricane Floyd From: RLLaney@....... Date: Wed, 15 Sep 1999 15:18:39 EDT Microseisms from Floyd began yesterday and are increasing in amplitude as the hurricane moves in our direction. Center is suppose to move just to our east tomorrow. Bob Laney Herndon, VA _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Microseisms from Hurricane Floyd From: Dick Webb dwebb2@.............. Date: Wed, 15 Sep 1999 20:13:35 -0400 Glad to hear that you can keep running. I had to vacate my vault and turn off the data computer as I think we are in the path of Floyd. Raleigh, NC is on the western edge of the probable path of the hurricane. Heads up and keep safe. Dick At 03:18 PM 09/15/1999 -0400, RLLaney@....... wrote: >Microseisms from Floyd began yesterday and are increasing in amplitude as the >hurricane moves in our direction. Center is suppose to move just to our east >tomorrow. > >Bob Laney >Herndon, VA > >_____________________________________________________________________ > >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) Subject: Re: Microseisms from Hurricane Floyd From: "Rex Klopfenstein, Jr." rklopfen@......... Date: Wed, 15 Sep 1999 21:01:01 -0400 Yesterday (9/14) everything was normal. Now tonight (9PM 9/15) my noise levels have tripled! > At 03:18 PM 09/15/1999 -0400, RLLaney@....... wrote: > >Microseisms from Floyd began yesterday and are increasing in amplitude as the > >hurricane moves in our direction. Center is suppose to move just to our east > >tomorrow. > > > >Bob Laney > >Herndon, VA -- Rex Klopfenstein, Jr. Bowling Green, OH rklopfen@......... http://www.wcnet.org/~rklopfen _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: dynamic range requirements From: S-T Morrissey sean@........... Date: Wed, 15 Sep 1999 21:43:58 -0500 (CDT) Warren, You asked about the dynamic range required of seismometers. The range of ground motions expected from earthquakes as recorded by a seismometer is hugh. Obviously if "you are there" at the fault scarp, you will need an accelerometer with a range to 2gs. But most instrumental seismology follows general magnitude formulas of the classic form: M = log(A/T) + 1.66*log(distance) + constant. The constant is a regional variable, usually about -0.18. The distance is degrees (111 km per), A is the ground amplitude in nanometers, and T is the period of the wave in seconds. For Ms calculations, A is the sustained peak-peak surface wave amplitude. You can plug in numbers for various scenarios. To answer your question about what will happen in the seismometer, solve for A: log(A/T) = Ms - 1.66*log(distance) + 0.18 A = T*log^-1(Ms -1.66*log(d) + 0.18. Considering the Turkey quake: the record here was 150 microns/second at 24 seconds. 24 seconds is an w (omega) of 2*pi/24 = 0.262radian/sec. The velocity is converted to displacement by dividing by w, so 150/0.262 = 573 microns or 5.73x10^5 nanometers. (0.573 millimeters) So Ms = log(5.73x10^5/24) + 1.66*log(81deg) -0.18 = 7.37 (a maximum magnitude of 8.0 at that distance would cause 2.46 millimeters of motion at St. Louis) But what did I record for the Ms = 5.8 aftershock? A = 24[log^-1(5.8 - 3.17 + 0.18) = 15 564 nanometers. (15.5 microns) This is a velocity (at 24 seconds) of 4.07 microns/second. With an output of 5.3mv/micron/sec, the record here was about 22 millivolts p-p, or about 10 times the 6-second microseisms.(At 0.5 microns p-p; today they are running more than 10 times that due to the hurricane). But what about a nearby quake? Say a Ms 4.0 in the next state? Putting numbers in the formula with distance = 3 degrees (200 miles) and T = 0.3 second, the seismometer will record 0.81 microns. For a magnitude 3, it will only sense 0.081 microns or 81 nanometrers. (using the local Mblg(3hz) formula gives 43 nanometers) If M = 4 and is 1000km away, the motion at 1 second will be 398 nanometers. If M = 3 and is 1000km away, the motion at 1 second will be 40 nanometers. For a threshold event, say a 2.5 at 110 km with T = 0.22 sec (4.5hz), (this magnitude formula is revised for such local events, but we'll use it anyhow) the amplitude is 105 nanometers. (using the local Mblg formula gives 56 nanometers). To record these with useful signal-to-noise ratio requires a resolution of 1 nanometer from the seismometer. SO.... we need a displacement dynamic range of 1 nanometer to 1 millimeter, or 10^6. This is one reason seismometers prefer a velocity output. Looking at such numbers:. At 10 hz, 1 nanometer is 63nm/sec. At 1 hz, it is 6.3nm/sec. At 20 seconds (a broadband instrument) 1 millimeter is 314 microns/second. This is a velocity range of about 50 000 to 1, which is the same as the voltage output range. Until recently this range was difficult to handle with analog electronics, so multi-level recording was used. A 16-bit digitizer can realize this if noise is ignored. Providing for noise and instrumental drift increases the required range by a factor of 100 to 1000. So modern broadband stations use 24-bit digitizers with a resolution of 1 part on 16 777 216 with a least count value of 1.2 microvolts. For a seismometer with a VBB velocity output of 2000 volts/meter/second, the LSB represents 1.67 nanometers/sec. The maximum value is 10 millimeters/second p-p. Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: microseisms From: S-T Morrissey sean@........... Date: Thu, 16 Sep 1999 01:19:51 -0500 (CDT) Microseisms from hurricane Floyd: This evening the 6-second microseisms have peaked at about 6 microns peak-peak at St. Louis. This is about 15 x the normal value. They should be readily seen on any seismograph with an operating period longer than 1 second. Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: microseisms From: Karl Cunningham karlc@....... Date: Thu, 16 Sep 1999 10:18:31 -0700 If one were to construct an undamped mechanical system resonant at 6 seconds, such as a Lehman, inverted pendulum, rocking chair, ball rolling in a very shallow bowl, etc., could you see it move with the naked eye when excited with these microseisms? If so, put it in a clear case to keep air currents off and this could make a striking display for schools, the public, etc. Karl Cunningham La Mesa, CA. PSN station #40 karlc@....... At 01:19 AM 9/16/1999 -0500, Sean-Thomas wrote: >Microseisms from hurricane Floyd: > >This evening the 6-second microseisms have peaked at about >6 microns peak-peak at St. Louis. This is about 15 x the >normal value. They should be readily seen on any seismograph >with an operating period longer than 1 second. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Computer question From: meredithlamb@.............. Date: 16 Sep 1999 20:36:08 -0700 Hi all, Have a computer question, about a computer screen I get on turnoff/shutdown; it says: DPMS off mode Anyone know the meaning, and/or what to do about it, or correct? Trying to install a SDR card in the machine, don't know if this "DPMS off mode" monitor note would affect such, in operation. Thanks, Meredith Lamb Signup for your free USWEST.mail Email account http://www.uswestmail.net _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Computer question From: Karl Cunningham karlc@....... Date: Thu, 16 Sep 1999 23:53:22 -0700 Meredith -- We have several computers at work that do that too. It is a message from the monitor's processor saying that it has stopped getting regular video data from the computer's graphics card and it is about to shut off the monitor's power. It is part of the energy saving features of newer monitors. They could have picked a better way of relating the message, but it doesn't hurt anything and is a normal situation. It shouldn't affect SDR operation. Karl Cunningham At 08:36 PM 9/16/1999 -0700, you wrote: >Hi all, > >Have a computer question, about a computer screen >I get on turnoff/shutdown; it says: > >DPMS off mode > >Anyone know the meaning, and/or what to do about >it, or correct? > >Trying to install a SDR card in the machine, don't >know if this "DPMS off mode" monitor note would >affect such, in operation. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: ??? Imples that G-force is a beam. From: EK kerls@...... Date: Fri, 17 Sep 1999 22:24:14 -0500 Attention: Mr. Cochrane Jerry Shifman S-T Morrissey In reply to your asking if I was implying that Earth's gravitational fields are beams. In short " No", they are not beams. The Earth's gravitational fields of force are individual micro fields of force. [ 28-12cm by about 1,380,000 miles ] with two poles, all of witch one faces the Earth's core, [ Thus the C-Pole. ] and the other that all of with faces universe, [ Thus the U-Pole. ] This is what gives us the elusion of being a single field of force with an omnidirectional force / pull. Gravitational fields of force are the weakest of the known fields of force. The Earth's gravitational fields of force are like magnetic fields with one big exception. The particles and the actions of the particles that spins out these fields can not conduct. This is to have the ability to move from one atomic system to another atomic system like the electrons that spins out magnetic fields from each level of electrons in the magnetic mass, thus making a single fat field with many lines of force in each level of orbiting electrons of the magnetic mass thus making a much denser field of force. With out the ability to conduct the particles that spin out the gravitational fields can only polarize each of the systems end to end making very slim but very long field of force. The systems that I just talked about are the systems of three quarks in the Proton and the system of three quarks in the Neutron. these are the six particles that spin out the Earth's gravitational fields of force. The ' TOP ' quark the last one to found is much larger than the others. This is what causes the atomic systems to warble / vibrate at citron frequencies. Under the conditions at the Earth's core level. This off balanceing by the " TOP " quark in these polarized gravitational fields of force gives the fields a frequency of about 2.1GHz. But this shouldn't be a surprise. Just think about who and what discovery won the Nobel Prize for physics in 1965. Six lines of force shouldn't be a surprize eather for we have known for a time now the gravity is the weakest of all the known fields of force. Also , what in nature comes by the trillions apron trillions , but none are alike, but all have six sides. " Snowflakes. " Yes gravity is the force that forces togther the water vpor / clouds to from rain and snow, of couse at the right temperatures. Oh I could go on and on with more facts and a lot of math, but I think that this is enough for tonight. Maj. Edward E. Kerls A.R. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: microseism display From: S-T Morrissey sean@........... Date: Fri, 17 Sep 1999 23:58:11 -0500 (CDT) Karl, Regarding your suggestion of visualizing the 6-second microseisms. It would take a very high Q (undamped) resonant system to get the 1 to 5 micron motion up to some visible scheme, and even then some optical magnification would be necessary.. But it would be fairly easy to amplify the output of a long period seismometer and connect the signal to a galvanometer or another seismometer. A light beam (pencil lasar (with a diffuser for safety)) shining off a mirror on the boom of the driven seismometer to a screen on a wall would make the amplified ground motion quite visible. The amplification can be adjusted for the best effect. This would provide a dynamic demonstration of the "restless earth" that people can relate to easier than minute wiggles on a PC screen. And during a quake, the lasar spot would swing from the ceiling to the floor. There was a use of high Q physical resonance in the days of moving- coil seismometers with galvanometric photo-recording. Since the whole system was passive, filters were a problem. So to filter the 6-second noise, a 6-second galvanometer was connected into the coupling network so that it was half damped. It would oscillate with the 6-second noise and absorb the energy. Later when very large computer capacitors came along, I was able to make a twin-tee 6-second notch filter with an 80 ohm impedance (for the galvo) that used 120 000 ufarad capacitors. Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Sensor Magazine ? From: Arie Verveer ajbv@............ Date: Sat, 18 Sep 1999 16:56:15 +0800 Hi, Way back, I remember that a PSN message was posted that had a "URL" to a magazine dedicated to Sensors. Can anybody recall the magazine and its "URL". I was planning to search for the word "sensor" through the PSN mailing list, but realized the hit rate would be high! Arie _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Sensor Magazine ? From: wizard@......... (Rick Jerome) Date: Sat, 18 Sep 1999 05:22:15 -0700 www.sensormag.com Execllent magazine. Always look forward to the new issues. ----- Original Message ----- From: Arie Verveer To: PSN-L Mailing List Sent: Saturday, September 18, 1999 01:56 Subject: Sensor Magazine ? > Hi, Way back, I remember that a PSN message was posted that had > a "URL" to a magazine dedicated to Sensors. Can anybody recall > the magazine and its "URL". I was planning to search for the word > "sensor" through the PSN mailing list, but realized the hit rate would > be high! > > Arie > > > > _____________________________________________________________________ > > 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) Subject: Re: Sensor Magazine ? From: jimo17@........ Date: Sat, 18 Sep 1999 05:59:24 -0700 Rick- I believe you left the 's' out of 'sensors', I just found it, and it looks great, thanks. http://www.sensorsmag.com/ Jim _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: GPS Time system From: "Giovanni Rotta" rottag@.......... Date: Sat, 18 Sep 1999 15:36:49 +0200 Hi, Larry ! I have connected your GPS system to my computer and setted SDR program. It works fine ! Have my best compliments ! Some question... It don't shows the elevation. I see by the position.log file that there are little changes in the = Latitude and Longitude data. It is possibile to recover the antenna into a little plastic box to = protect it by rain, snow and ice ? Thank you more for your help and beautiful system !! Giovanni Giovanni Rotta Via F. Pizzigoni, 10 33010 Resia (Udine) I Lat. 46.373 N Long. 13.305 E rottag@.......... http://www.resianet.org
Hi, Larry !
I have connected your GPS system to my computer = and setted=20 SDR program.
It works fine ! Have my best compliments = !
Some question...
It don't shows the elevation.
I see by the position.log file that = there are little=20 changes in the Latitude and Longitude data.
It is possibile to recover the antenna into a = little=20 plastic box to protect it by rain, snow and ice ?
Thank you more for your help and beautiful = system=20 !!
Giovanni
 
Giovanni Rotta
Via F. Pizzigoni, 10
33010 = Resia=20 (Udine) I
Lat. 46.373 N  Long. 13.305 E
rottag@..........
http://www.resianet.org
= Subject: Re: Sensor Magazine ? From: Doug Crice dcrice@............ Date: Sat, 18 Sep 1999 07:52:04 -0700 Close, try http://www.sensorsmag.com/ Rick Jerome wrote: > > www.sensormag.com > > Execllent magazine. Always look forward to the new issues. > > ----- Original Message ----- > From: Arie Verveer > To: PSN-L Mailing List > Sent: Saturday, September 18, 1999 01:56 > Subject: Sensor Magazine ? > > > Hi, Way back, I remember that a PSN message was posted that had > > a "URL" to a magazine dedicated to Sensors. Can anybody recall > > the magazine and its "URL". I was planning to search for the word > > "sensor" through the PSN mailing list, but realized the hit rate would > > be high! > > > > Arie > > > > > > > > _____________________________________________________________________ > > > > 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 -- 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) Subject: Re: Sensor Magazine ? From: "Al Allworth" allworth@.............. Date: Sat, 18 Sep 1999 22:03:13 -0700 www.sensormag.com seems to lead to MotionSearch.com which is under construction. ____________________________________ Al Allworth allworth@.............. Gold Beach On The Beautiful Southern Oregon Coast ____________________________________ ----- Original Message ----- From: Rick Jerome To: PSN-L Mailing List Sent: Saturday, September 18, 1999 5:22 AM Subject: Re: Sensor Magazine ? > www.sensormag.com > > Execllent magazine. Always look forward to the new issues. > > ----- Original Message ----- > From: Arie Verveer > To: PSN-L Mailing List > Sent: Saturday, September 18, 1999 01:56 > Subject: Sensor Magazine ? > > > > Hi, Way back, I remember that a PSN message was posted that had > > a "URL" to a magazine dedicated to Sensors. Can anybody recall > > the magazine and its "URL". I was planning to search for the word > > "sensor" through the PSN mailing list, but realized the hit rate would > > be high! > > > > Arie > > > > > > > > _____________________________________________________________________ > > > > 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) Subject: Re: Sensor Magazine ? Correction on URL From: wizard@......... (Rick Jerome) Date: Sun, 19 Sep 1999 06:25:19 -0700 Think I should have gotten some more sleep. The URL should be www.sensorsmag.com. Sorry about the error. Am re-doing my lab and it is chaos in here. Was trying to do it from memory. Michael Duck N6EGQ Telemetry Systems Tuolumne Utilities District _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Thin Flexible Refrigerator Magnets From: meredithlamb@.............. Date: 19 Sep 1999 19:09:44 -0700 Hi all, Hmmm...just noted tonight that these common thin magnets seem to have a property I've not noted before. On one side, they stick magnetically OK. On the other side, it's almost like their wasn't almost even a magnet there. Have 3 such critters on the refrig steel side, 2 have very little attraction on the paper side, and 1 seems like its field has been cut down 2/3rds. Even on a flat steel surface, the difference is notable. Anyone know what kind of property these magnets have to act the way they do? OR; Perhaps the manufacturers only magnetize on one side to a very shallow depth into the magnet? Meredith Lamb Signup for your free USWEST.mail Email account http://www.uswestmail.net _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Thin Flexible Refrigerator Magnets From: "Anders Heerfordt" aheerfor@...... Date: Mon, 20 Sep 1999 06:17:03 +0200 > Anyone know what kind of property these magnets have to act the way they do? < They have a row of alternating N and S poles on one side (the magnetic side) Regards, Anders _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Thin Flexible Refrigerator Magnets From: Raul Alvarez ralvarez@........ Date: Mon, 20 Sep 1999 07:34:46 -0600 Meredith, I think that a lot of that has to do with the painted surface. It keeps just enough seperation that you can't get a good contact. Usually they are painted with a fairly thick coat of paint. That's my guess. Raul meredithlamb@.............. wrote: > Hi all, > > Hmmm...just noted tonight that these common thin > magnets seem to have a property I've not noted > before. On one side, they stick magnetically OK. > On the other side, it's almost like their wasn't > almost even a magnet there. Have 3 such critters > on the refrig steel side, 2 have very little > attraction on the paper side, and 1 seems like > its field has been cut down 2/3rds. Even on a > flat steel surface, the difference is notable. > > Anyone know what kind of property these magnets > have to act the way they do? > > OR; > > Perhaps the manufacturers only magnetize on one > side to a very shallow depth into the magnet? > > Meredith Lamb > > > > Signup for your free USWEST.mail Email account http://www.uswestmail.net > > _____________________________________________________________________ > > 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) Subject: Quake in progress From: "Francesco" franuc@...... Date: Mon, 20 Sep 1999 20:12:30 +0200 Large P until now=20 Have someone the same? Francesco, Italy
Large P until now
Have someone the=20 same?
 
Francesco, = Italy
Subject: Incoming teleseismic... From: meredith lamb mlamb1@.......... Date: Mon, 20 Sep 1999 12:17:27 +0000 Seeing incoming L waves at this time. Looks to be south of the U.s. per amplitude. Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Large quake in eastern Asia From: "Francesco" franuc@...... Date: Mon, 20 Sep 1999 20:20:27 +0200 Now very large S Preliminary location: about 9600 km from Italy, China- Russia border region (Sahkalin?) M ~6.4 Francesco
Now very large S
 
Preliminary location:
about 9600 km from Italy,  China- = Russia=20 border region (Sahkalin?)
M ~6.4
 
Francesco
Subject: R: Incoming teleseismic... From: "Francesco" franuc@...... Date: Mon, 20 Sep 1999 20:24:04 +0200 Hello Meredith Here is incoming the third phase. Some difficult yet for exact determination. However, Asian quake! Francesco _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: More on quake... From: "Francesco" franuc@...... Date: Mon, 20 Sep 1999 20:29:23 +0200 Nice view from USGS telemetry network connection at = http://aslwww.cr.usgs.gov/Seismic_Data/heli2.htm Asian stations are strong excitated... Taiwan, Korea and Russia with signal out of scale! Francesco
Nice view from USGS telemetry network = connection at=20 http://aslwww.c= r.usgs.gov/Seismic_Data/heli2.htm
 
Asian stations are strong = excitated...
Taiwan, Korea and Russia with signal = out of=20 scale!
 
Francesco
 
Subject: Re: Large quake in eastern Asia From: meredithlamb@.............. Date: 20 Sep 1999 11:29:49 -0700 On Mon, 20 September 1999, "Francesco" wrote: > > Now very large S > > Preliminary location: > about 9600 km from Italy, China- Russia border region (Sahkalin?) > M ~6.4 > > Francesco Thanks Francesco. Fairly strong vertical component to this quake here, in comparison to past quakes. Hard to discern indivdual instrument traces now. Meredith Lamb Signup for your free USWEST.mail Email account http://www.uswestmail.net _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Tsunami Warning/Watch Bulletin From: John Lahr lahr@................... Date: Mon, 20 Sep 1999 12:40:45 -0600 (MDT) ------------- Begin Forwarded Message ------------- From: TWS Operations Date: Mon, 20 Sep 1999 18:35:29 GMT To: bulletin@............. Subject: Tsunami Warning/Watch Bulletin Mime-Version: 1.0 TSUNAMI BULLETIN NUMBER 001 PACIFIC TSUNAMI WARNING CENTER/NOAA/NWS ISSUED 20 SEP, 1830 UTC THIS BULLETIN IS FOR ALL AREAS OF THE PACIFIC BASIN EXCEPT CALIFORNIA, OREGON, WASHINGTON, BRITISH COLUMBIA, AND ALASKA. .. . . A TSUNAMI WARNING AND WATCH ARE IN EFFECT . . . A TSUNAMI WARNING IS IN EFFECT FOR: TAIWAN, JAPAN, PHILIPPINES, BELAU, YAP, GUAM A TSUNAMI WATCH IS IN EFFECT FOR: MARCUS IS., RUSSIA, CHUUK, MARSHALL IS., HONG KONG, WAKE IS. FOR OTHER AREAS IN THE PACIFIC, THIS MESSAGE IS FOR INFORMATION ONLY. AN EARTHQUAKE, PRELIMINARY MAGNITUDE 7.6, OCCURRED 20 SEP, 1747 UTC. COORDINATES: LATITUDE 23.8 NORTH, LONGITUDE 121.3 EAST VICINITY: TAIWAN. EVALUATION: IT IS NOT KNOWN THAT A TSUNAMI WAS GENERATED. THIS WARNING AND WATCH ARE BASED ONLY ON EARTHQUAKE EVALUATION. ESTIMATED TIMES OF INITIAL WAVE ARRIVAL AT LOCATIONS WITHIN THE WARNING AND WATCH AREAS ARE: HUALIEN,TAIWAN 1747Z 20 SEP OKINAWA,JAPAN 1905Z 20 SEP LEGASPI,PHILIPPINES 1951Z 20 SEP SHIMIZU,JAPAN 2008Z 20 SEP MALAKAL,PALAU 2038Z 20 SEP YAP 2042Z 20 SEP GUAM,USA 2111Z 20 SEP MARCUS 2202Z 20 SEP HACHINOHE,JAPAN 2225Z 20 SEP TRUK,FSM 2240Z 20 SEP ENIWETOK,MARSHALL ISLS 2330Z 20 SEP HONG KONG 2343Z 20 SEP WAKE,USA 2343Z 20 SEP KWAJALEIN,MARSHALL ISLS 0024Z 21 SEP BULLETINS WILL BE ISSUED HOURLY OR SOONER IF CONDITIONS WARRANT. THE TSUNAMI WARNING WILL REMAIN IN EFFECT UNTIL FURTHER NOTICE. RECIPIENTS OF THIS MESSAGE LOCATED IN CALIFORNIA, OREGON, WASHINGTON, BRITISH COLUMBIA, AND ALASKA SHOULD REFER ONLY TO ALASKA TSUNAMI WARNING CENTER MESSAGES FOR INFORMATION ABOUT ANY TSUNAMI THREAT IN THOSE AREAS. ------------- End Forwarded Message ------------- _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: R: Incoming teleseismic... From: meredithlamb@.............. Date: 20 Sep 1999 11:41:12 -0700 On Mon, 20 September 1999, "Francesco" wrote: > > Hello Meredith > Here is incoming the third phase. > Some difficult yet for exact determination. > However, Asian quake! > > Francesco OK Francesco, Hard to gauge the vertical L wave periods, maybe 12 to 20s in spots, per monitor. Horizontal periods maybe 10s to 15s. Time will tell. Useful to me as I tried changing the capacitors on the Halls instruments, and checking the comparison to that of the regular coil/magnet instruments. Interesting...doesn't mean it works any better, but still interesting. I see even longer period stuff rolling in now... Very interesting....am sure the long period stuff exceeds the normal coil/magnet instrument period. Meredith Lamb Signup for your free USWEST.mail Email account http://www.uswestmail.net _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: REVIEWED LOCATION FROM USGS/NEIC From: John Lahr lahr@................... Date: Mon, 20 Sep 1999 12:48:05 -0600 (MDT) ------------- Begin Forwarded Message ------------- Date: Mon, 20 Sep 1999 18:37:28 GMT From: MINSCH@................ To: lahr@................... Subject: REVIEWED LOCATION FROM USGS/NEIC Mime-Version: 1.0 STAP 99/09/20 17:47:19 23.78N 121.09E 33.0 7.6Ms A TAIWAN ------------- End Forwarded Message ------------- _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Taiwan quake From: meredithlamb@.............. Date: 20 Sep 1999 11:54:33 -0700 Hi all, Thanks John Lahr for the info. This quake is setting off all my trigger levels, just afew minutes ago. Exceptionally long period L waves. I use the vertical for the main trigger, all the rest were set high, to suppress noise induced events. Meredith Lamb Signup for your free USWEST.mail Email account http://www.uswestmail.net _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Taiwan quake From: meredithlamb@.............. Date: 20 Sep 1999 12:04:44 -0700 All, This looks to be a deadly quake, probably affecting many areas around it. Front page news, I'am sure. Monitor totally smirred here now. Meredith Lamb Signup for your free USWEST.mail Email account http://www.uswestmail.net _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Taiwan quake From: Kees Verbeek kverb@........ Date: Mon, 20 Sep 1999 21:43:08 +0200 (CEST) Hi all, Just came back from a long iceland-trip ,first night that I connect my seismograph again(still the "old" Bosch). I am afraid that this one is realy big ,my pen broke,and I could even see my pendulum swing,till it did hit the max. safety-pins. Bad news on my "first" night!!!!!! Greetings, Kees Verbeek ,Holland _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Quake in progress From: TORBEN THAMS tobythams@................ Date: Mon, 20 Sep 1999 13:54:58 +0100 ....it is a 7.6 in Taiwan Torben "Toby" Thams _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Incoming teleseismic... From: TORBEN THAMS tobythams@................ Date: Mon, 20 Sep 1999 13:56:28 +0100 ....a 7.6 in Taiwan Torben "Toby" Thams So. Calif. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Taiwan quake From: Kees Verbeek kverb@........ Date: Tue, 21 Sep 1999 00:41:04 +0200 (CEST) Another Quake is coming in ,aftershock? Kees Verbeek, hOLLAND _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Taiwan quake From: meredithlamb@.............. Date: 20 Sep 1999 15:53:31 -0700 On Mon, 20 September 1999, Kees Verbeek wrote: > > Another Quake is coming in ,aftershock? > > Kees Verbeek, hOLLAND > Hi Kees, Only getting in long period waves here, but low level. About 20s period. Can't see P-S. Meredith Lamb Signup for your free USWEST.mail Email account http://www.uswestmail.net _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Taiwan broadband sensor From: Larry Cochrane cochrane@.............. Date: Mon, 20 Sep 1999 20:31:47 -0700 All, One of the broadband sensors I am monitoring using the Internet (see http://aslwww.cr.usgs.gov/Seismic_Data for more info) is the Taiwan broadband sensor TATO. I placed an event file on my system showing what it recorded for the main event. The event file can be downloaded at ftp://ftp.seismicnet.com/quakes/9909/990920a.bhz.tato. As you can see the sensor saturated very soon after the P wave. The sensor is was only 138km (~86 miles) from the event. The sensor went off-line a few hours ago, so I'm not receiving anymore data from it... -Larry Cochrane Redwood City, PSN _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Taiwan aftershocks From: S-T Morrissey sean@........... Date: Mon, 20 Sep 1999 22:48:16 -0500 (CDT) Regarding aftershocks to the Taiwan quake: here is the current NEIS lsiting. The aftershocks ARE large; generally the largest aftershocks are 2 (+-0.5 ) magnitude units less than the main shock. So much for generalities .... Regards, Sean-Thomas NEIS listing: Updated as of Mon Sep 20 17:10:38 MDT 1999. DATE-(UTC)-TIME LAT LON DEP MAG Q COMMENTS yy/mm/dd hh:mm:ss deg. deg. km 99/09/18 23:25:19 22.80S 66.10W 261.7 4.3Mb B JUJUY PROVINCE, ARGENTINA 99/09/18 23:51:30 19.79S 169.28E 103.6 5.8Mb A VANUATU ISLANDS 99/09/19 03:18:54 3.58S 150.91E 426.2 5.3Mb A NEW IRELAND REGION, P.N.G. 99/09/19 11:16:15 16.55S 74.00W 33.0 4.8Mb A NEAR COAST OF PERU 99/09/19 16:46:59 43.07N 46.82E 33.0 4.8Mb B EASTERN CAUCASUS 99/09/19 19:59:24 6.55S 154.58E 33.0 5.1Mb B SOLOMON ISLANDS 99/09/19 20:25:02 52.45N 179.92E 67.5 4.3Mb C RAT ISLANDS, ALEUTIAN ISLANDS 99/09/20 04:16:34 51.22N 176.84W 33.0 4.2Mb B ANDREANOF ISL, ALEUTIAN IS. 99/09/20 07:02:49 34.32N 116.85W 5.6 4.2Ml SOUTHERN CALIFORNIA 99/09/20 07:34:11 54.41N 168.26E 33.0 4.8Mb A KOMANDORSKY ISLANDS REGION 99/09/20 07:53:49 54.50N 168.21E 33.0 4.2Mb A KOMANDORSKY ISLANDS REGION 99/09/20 09:32:42 46.73N 153.18E 33.0 5.2Mb A KURIL ISLANDS 99/09/20 10:18:52 31.86N 40.49W 10.0 4.8Mb B NORTHERN MID-ATLANTIC RIDGE 99/09/20 17:47:19 23.78N 121.09E 33.0 7.6Ms A TAIWAN 99/09/20 17:57:16 23.80N 121.34E 33.0 6.0Mb B TAIWAN 99/09/20 18:03:44 23.65N 121.36E 33.0 5.9Mb B TAIWAN 99/09/20 18:11:53 23.75N 121.19E 33.0 6.1Mb B TAIWAN 99/09/20 18:16:18 23.69N 121.31E 33.0 6.1Mb B TAIWAN 99/09/20 20:40:08 24.09N 121.95E 33.0 5.1Mb C TAIWAN 99/09/20 21:27:59 40.70N 27.62E 10.0 4.5Mb A TURKEY 99/09/20 21:46:44 23.61N 121.12E 33.0 6.4Ms B TAIWAN ___________________________________________________ _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Taiwan news From: meredithlamb@.............. Date: 20 Sep 1999 21:33:05 -0700 Most major news services have online data/news on the quake. http://www.cnn.com http://abcnews.go.com http://www.usatoday.com Haven't heard of any water bodys/lakes doing seiches from it. If I remember right, the Turkey quake of the same rough size, did. Anybody watch a pendulum during a large quake oscillate, like Kees did in the Netherlands? Unique for sure. Meredith Lamb Signup for your free USWEST.mail Email account http://www.uswestmail.net _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: R: Taiwan broadband sensor From: "Francesco" franuc@...... Date: Tue, 21 Sep 1999 08:34:14 +0200 Larry, which is the right address to download the file of USGS word telemetry? Francesco _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: taiwan event.... an interesting note From: "David A. Nelson" davenn@........ Date: Tue, 21 Sep 1999 19:53:41 +1200 going back through the records i find today's even is very close to a larger event in 1986 99/09/20 17:47:19 23.78N 121.09E 33.0 7.6Ms A TAIWAN major damage and 1000+ dead so far and back then..... 86/11/14 212004.6 23.96N 121.82E 33 Mb6.2 Ms7.8 TAIWAN cheers Dave Co-ordinator: New Zealand Public Seismic Network Dave A. Nelson ZL4TBN 23 Duncan St., Dunedin, South Is.. New Zealand. http://www.seismicnet.com/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) Subject: Re: R: Taiwan broadband sensor From: Mhammed kamal eldin salah msalah@................. Date: Tue, 21 Sep 1999 11:40:06 +0300 (EET DST) On Tue, 21 Sep 1999, Francesco wrote: > Larry, > which is the right address to download the file of USGS word telemetry? > > Francesco > > > _____________________________________________________________________ > > 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) Subject: Re: R: Taiwan broadband sensor From: Mhammed kamal eldin salah msalah@................. Date: Tue, 21 Sep 1999 11:40:06 +0300 (EET DST) On Tue, 21 Sep 1999, Francesco wrote: > Larry, > which is the right address to download the file of USGS word telemetry? > > Francesco > > > _____________________________________________________________________ > > 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) Subject: travel times From: John Lahr lahr@................... Date: Tue, 21 Sep 1999 11:42:57 -0600 (MDT) ------------- Begin Forwarded Message ------------- Date: Tue, 21 Sep 1999 11:30:14 -0600 (MDT) From: John Lahr Subject: travel times To: blewis@.............. Cc: lahr@................... MIME-Version: 1.0 Content-MD5: 25ZXK6XSkC0uEyy2EokPDQ== Bob Lewis Plano, TX Hi Bob, I just checked and the computer gldfs has crashed due to the load of hits folling the Taiwan earthquake. It is being rebooted now. There are two work-arounds. One: instead of selecting the NEIC - USGS National Earthquake Information Center select: NEIC - Accumulated listing from past 45 days (This listing is updated each morning.) The other is: Go to this page: http://geohazards.cr.usgs.gov/tt/ and select: Compute arrival times at Your seismic station for a specified earthquake and plug in the coordinates of the Taiwan earthquake. Good talking to you today. I'll cc this to the PSN, as some others may have run into the problem with finger quake@................. 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 ------------- End Forwarded Message ------------- _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: AGU Pictures... From: Edward Cranswick cranswick@........ Date: Tue, 21 Sep 1999 14:30:33 -0600 Jan- I just took a breather from Turkey to check out your PSN/AGU pictures on the SVJHB website, and they are great! Seeing them makes me understand how successful that show was after all (I tended to remember only my bureaucratic interactions with AGU): the kids are alright! Quite aside from anything else we have accomplished together, putting all those pieces together at the San Francisco AGU represents quite an achievement for a decade of PSN. Three Turkish colleagues are arriving tonight from the Earthquake Engineering Department, Kandilli Observatory & Earthquake Research Institute, Bogaziçi University, Istanbul with whom we worked when we were there two weeks ago. The Director of the Department, Professor Mustafa Erdik (Chair), has been a PSN member for years because he likes to keep up with our low-rent approach to technological innovation. Mustafa was the one who responded when Meredith asked on PSN-L where I had disappeared to and said that I was safely in his office in Turkey: so no matter where you go, that's where you are. I hope you are well. -Edward PS. I am sending some hardcopies of the PSN/AGU pictures to my mother in Australia to let her know what I am doing with my life. "Jan D. Froom" wrote: > Ted.... while I don't have it linked to anything yet.... I do have some > of the AGU pictures on my school web site at: > > http://www.gusd.k12.ca.us/schools/svjhb/weather/agumeet.htm > > You might correct any gross errors, before I make it public..... Sorry > that I don't have more Almaden pictures... but most of the pictures I > got from you were pictures of backs.... > > How are making out with the STORMS ? Did the earlier one get you wet ? > The guys on the PSN net are talking about watching the storm on their > seismometers. > > Jan.... -- 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) Subject: quake again. From: Kees Verbeek kverb@........ Date: Wed, 22 Sep 1999 03:07:39 +0200 (CEST) hi, all Quake coming in at this moment ? Kees Verbeek, Netherlands _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: quake again. From: Seisguy@....... Date: Tue, 21 Sep 1999 21:10:34 EDT In a message dated 09/21/1999 6:08:10 PM Pacific Daylight Time, kverb@........ writes: << hi, all Quake coming in at this moment ? Kees Verbeek, Netherlands >> D a t e Time (UTC) Location Dep Magn. T AGY R e g i o n HHMM 22Sep1999 00:14:43.0 22.0N 119.0E 10 mb=6.1 A*LED TAIWAN REGION 0034 22Sep1999 00:14:41.2 25.7N 123.4E 10 mb=6.2 A*SED NORTHEAST OF TAIWAN 0032 _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: quake again. From: Seisguy@....... Date: Tue, 21 Sep 1999 21:24:26 EDT And another D a t e Time (UTC) Location Dep Magn. T AGY R e g i o n HHMM 22Sep1999 00:49:46.1 25.3N 119.5E 33 mb=6.0 A*NEI NEAR SOUTHEASTERN COAST O0115 22Sep1999 00:49:36.0 23.0N 122.0E 33 mb=5.6 A*YKA TAIWAN REGION 0113 22Sep1999 00:49:44.0 21.0N 119.0E 10 mb=5.8 A*LED TAIWAN REGION 0109 22Sep1999 00:49:37.7 23.6N 122.8E 10 mb=5.9 A*SED TAIWAN REGION 010 _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: [Fwd: Taiwan earthquake information from Willie Lee] From: Edward Cranswick cranswick@........ Date: Tue, 21 Sep 1999 19:41:05 -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". ------------- Begin Forwarded Message ------------- Mime-Version: 1.0 X-Sender: mblanpied@.................. Date: Tue, 21 Sep 1999 13:04:41 -0700 To: wehz@........................ From: William Lee (by way of Michael Blanpied) Subject: Taiwan earthquake information from Willie Lee Dear Mike: I was probably the first person outside Taiwan to know about this earthquake. The e-mail containing the shock arrived several minutes after the earthquake, and a dozen more later on its aftershocks. The automatic system produced very reasonable estimates for epicenter, focal depth, and magnitude of the main shock in about 100 seconds after the earthquake's origin time. I faxed all the info to Dave Oppenheimer in the early afternoon of 9/20 after he called me. I came to the office later and left a big map with the "dots" in the press room of Building 3. Last night, I wrote a short note about the Taiwan EQ and sent it primarily to John Filson as he left me a phone message for more info. Please feel free to circulate this e-mail. One sad comment is that I was too optimistic. It appears that the epicentral area was hard hit and the dead toll is mounting. The peak PGA recorded at Chiayi (about 50 km southwest of the quake) was about 16% g acceleration. There are closer strong- motion stations, but they are not telemetered, and it appears that most phone communications are out as of now. Internet to Taiwan is still out as of now (12 noon; 9/21). After an intensive programs to instrument urban areas during 1991-1996, Taiwan has the highest concentrations of modern digital accelerographs of the world (about 5 times closer station spacing than Japan): about 1,000 digital accelerograhs in free sites, and an equivalence of over 500 accelerographs in structures (about 50 structures have been instrumented with an array of accelerometers and are monitored by a realtime system). The results reported below derived from about 70 continuously telemetered digital accelerographs, many at the local weather stations in urban areas. A few simple facts: (1) Taiwan has an area of about 8% of California or Japan. More than 1/2 of the area are mountainous (up to 4,000 meters). (2) It is very seismic active, because Philippines plate/Pacific Plate/Eurasia Plate converge there. Seismicity is about 3-5 times higher than California. (3) I am fortunate to have the opportunity to participate in their earthquake program while I was at the USGS before and after my retirement. (4) The Taiwan instrumentation program costed about $40 millions in 6 years (about 90% were spent on strong-motion). It was completed on time, under the budget (the program was budgeted at $72 million), and with only a few additional staff from their original staff of about 30 people. (5) Finally, I believe the "KISS" principal works, i.e., keeping it simple. Willie ====== Prepared by about 11 p.m, 9/20/99, Calif. time ============= Taiwan Quake: Results and Performance of Taiwan's Rapid Earthquake Information Release System At 1:47 a.m. Taiwan local time, a major earthquake occurred in Taiwan, about 140 km SSW of Taipei, its capital. Fortunately, the epicenter was located in the mountainous area, about 50 km southeast and northeast from two major cities: Taichung and Chiayi, respectively. Hundreds of people were killed and thousands were injured. The disaster would be similar to the recent Turkey quake if the epicenter were 50 km west in the coastal plain, where the population is very dense. I received the main shock information in an e-mail, several minutes after the earthquake occurred. The Taiwan's realtime system is based on about 70 continuously digital-telemetered accelerographs all over the island, and has been in operation since March 5, 1996. Data were automatically processed in Taipei using hardware and software designed and implemented in the early 1990's (Lee et al., 1996; Shin et al., 1996;). Early results had been published by Teng et al. (1997) and Wu et al. (1997). [see References after the table]. In the following table, I listed the results received as of 10 p.m., Sept. 20, California time (or 1 p.m., Taiwan local time), i.e., for a period of about 11 hours after the main shock. Several general conclusions are: (1) The Taiwan system performed as designed and has shown to be capable of handling probably the largest earthquake of this century in Taiwan. The first located aftershock occurred just 10 minutes after the main shock. There were many aftershocks and some were quite large. (2) The preliminary result of the main shock is reasonably accurate. The local magnitude was estimated to be 7.3 in about 100 seconds after the earthquake's origin time and agreed well with the Mw = 7.6 determined by NEIC in about 3 hours after the earthquake. Focal depth was 10 km vs 5 km given by the moment tensor solution of NEIC. (3) Hypocenter and magnitude were determined in about 100 seconds after the origin time, or about 90 seconds after sufficient number of stations recorded the first P-arrivals. Some extra time was spent in making sure that the largest amplitudes had been recorded. For some aftershocks, the processing time (Proc. Time in the following table) was less than 1 minute. The Proc. Time is defined to be the elapsed time from the earthquake's origin time to the time the results sent to the e-mail server. (4) E-mail transit time is quick in the beginning (middle of the night), taking only several minutes to get from Taipei to my home. However, by 5 a.m. local time, e-mails were backed up and for several hours, no e-mails arrived from Taiwan. Phone calls to Taiwan are not possible at this moment (12 hours after the quake and e-mails from Taiwan started to dribble in. The following lists the results from the Taiwan realtime system as received in e-mails after the first 11 hours of the quake. Results after the first two hours are probably not complete as the e-mails could not get out of Taiwan rapidly. ------------------------------------------------------------------- Date Origin Time Latitude Longitude Depth(Km) ML Proc. Time ------------------------------------------------------------------- 9/20/99 17:47:15.89 23.87 N 120.75 E 10.0 7.3 102 sec. 9/20/99 17:57:17.16 23.95 N 121.03 E 6.9 6.1 57 sec. 9/20/99 18:03:42.64 23.80 N 120.85 E 5.0 6.5 75 sec. 9/20/99 18:11:27.71 24.03 N 120.98 E 5.2 5.2 56 sec. 9/20/99 18:16:21.01 23.86 N 121.03 E 13.5 6.9 85 sec. 9/20/99 18:21:31.57 23.99 N 121.07 E 8.9 5.1 50 sec. 9/20/99 18:32:55.60 23.82 N 121.01 E 2.9 5.2 62 sec. 9/20/99 19:28:43.48 23.88 N 120.97 E 2.4 4.9 53 sec. 9/20/99 19:40:33.27 23.57 N 120.88 E 2.5 5.4 55 sec. 9/20/99 19:57:52.19 24.17 N 120.75 E 6.9 5.9 76 sec. 9/20/99 20:02:15.36 24.01 N 120.67 E 2.5 5.7 69 sec. 9/21/99 01:37:09.01 23.73 N 120.75 E 2.5 5.2 55 sec. 9/21/99 02:24:46.48 23.93 N 121.00 E 8.4 4.9 56 sec. 9/21/99 03:31:49.58 23.99 N 121.02 E 3.1 5.1 58 sec. ------------------------------------------------------------------- REFERENCES: Lee WHK, Shin TC and Teng TL (1996). Design and implementation of earthquake early warning systems in Taiwan. Proc. 11th World Conf. Earthq. Eng., Paper No. 2133. Shin TC, Tsai YB, and Wu YM (1996). Rapid response of large earthquake in Taiwan using a realtime telemetered network of digital accelerographs. Proc. 11th World Conf. Earthq. Eng., Paper No. 2137. Teng TL, Wu L, Shin TC, Tsai YB, and Lee WHK (1997). One minute after: strong motion map, effective epicenter, and effective magnitude. Bull. Seism. Soc. Am., vol 87, p 1209-1219. Wu YM, Shin TC, Chen CC, Tsai YB, Lee WHK, and Teng TL (1997). Taiwan rapid earthquake information release system. Seism. Res. Letters, vol 68, p 931-943. ------------- End Forwarded Message ------------- Subject: Taiwan 7.6 event From: barry lotz gbl@....... Date: Tue, 21 Sep 1999 20:04:21 -0700 I all I noticed that my events, and others in California (Karl and Larry) have a large wave arrival between the SSS anf the LQ phases. I looked in the travel time graph and did not see what phase that might be. Any thoughts? Barry _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Taiwan 7.6 event From: S-T Morrissey sean@........... Date: Tue, 21 Sep 1999 22:26:28 -0500 (CDT) Barry, My impression is that there are two events separated by about 4 minutes: a somewhat emergent P about 1/10 the amplitude of the main P about 4 minutes later. This somewhat confuses the interpretation of later phases. The event is very shallow, so complex phases are emergent and may be involved in early aftershocks. Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Taiwan 7.6 event From: barry lotz gbl@....... Date: Tue, 21 Sep 1999 21:05:40 -0700 Sean Thomas Thanks Barry _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Fireballs From: Oguzhan Aydogmus-HRB oaydogmus@................ Date: Wed, 22 Sep 1999 08:39:05 +0300 Hi all I live in Izmit , Turkey and experience everything. I have a question .During the earthquake in Izmit fireballs jumped out of sea ..What is it according to you? Thanks Oguzhan Aydogmus _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Fireballs From: "Anders Heerfordt" aheerfor@...... Date: Wed, 22 Sep 1999 08:38:36 +0200 > I have a question .During the earthquake in Izmit fireballs jumped out of sea ..What is it according to you? < An unexplainable mystery? Regards, Anders _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: RE: Fireballs From: Oguzhan Aydogmus-HRB oaydogmus@................ Date: Wed, 22 Sep 1999 10:00:00 +0300 Authoizeds said methane burst.But I thing it's not satisfy. > ---------- > From: Anders Heerfordt[SMTP:aheerfor@....... > Reply To: PSN-L Mailing List > Sent: 22 Eyl=FCl 1999 =C7ar=FEamba 09:38 > To: PSN-L Mailing List > Subject: Re: Fireballs >=20 >=20 > > > I have a > question .During the earthquake in Izmit fireballs jumped out of sea > .What is it according to you? > < >=20 > An unexplainable mystery? >=20 > Regards, Anders >=20 >=20 >=20 > _____________________________________________________________________ >=20 > Public Seismic Network Mailing List (PSN-L) >=20 > To leave this list email listserver@.............. with the body of > the=20 > message: leave PSN-L >=20 _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Fireballs From: Arie Verveer ajbv@............ Date: Wed, 22 Sep 1999 19:04:44 +0800 Hi Oguzhan Interesting question, and this may be a possible answer. I stress may be an answer. On the 25th of june I posted a copy of an article that I found in nature. It deals with light from earthquakes. Here is a copy of the posting on that date. Arie. > > ---------- > > From: Anders Heerfordt[SMTP:aheerfor@....... > > Reply To: PSN-L Mailing List > > Sent: 22 Eyl=FCl 1999 =C7ar=FEamba 09:38 > > To: PSN-L Mailing List > > Subject: Re: Fireballs > > > > > > > > > I have a > > question .During the earthquake in Izmit fireballs jumped out of sea > > .What is it according to you? > > < > > > > An unexplainable mystery? > > > > Regards, Anders ---------------------------------------------------------------- I came across this interesting article by Dr. A. C. Johnston in a scientific magazine called Nature. Sorry about the length of the document but I think its worth it. Arie -------------------------------------------------------------------- Article Nature Vol 354 (5 December 1991) page 361. By Arch C. Johnston Light from seismic waves Sir - Sonoluminescence (SL) - the production of light by the action of sound waves in liquid - has been observed and studied in the laboratory for more than 50 years. But I believe it has been observed in nature for centuries as earthquake lights (EQLs). EQLs are largely a coseismic occurrence, second only to pre-seismic abnormal behaviour for difficulty of reliable documentation and lack of a verifiable explanatory mechanism. Many explanations for the generation of EQLs exist (see refs 1-3). Most proposed mechanisms require assumptions such the presence of special minerals, gases or organisms, or unverified physical conditions in the fault zone. All have difficulty explaining the persistent reports of EQLs at distances of up to hundreds of kilometres from the earthquake, and at sea or in association with large bodies of both fresh and salt water or wetlands. I propose that at least some EQLs are not the product of high strain accumulation or shear rupture dynamics in fault zones, but rather result from molecular reactions in water that has been strongly shaken by the compressional (P) waves produced by the earthquake. A seismic wave is simply an earthquake generated sound wave in a solid or liquid; hence if a P wave induces light emission from liquid, it is a situation entirely analogous to SL as generated in the chemist's laboratory. SL is a remarkable consequence of acoustic cavitation in liquids irradiated by sound waves(4,5). For it to occur, a cavity or bubble must be created in the liquid continuum, then rapidly compressed. The process adiabatically heats the trapped gas or vapour sufficiently to dissociate molecules. On recombination or return to the ground state, photons are emitted. Once a cavity or bubble is formed, two types of SL are possible: "stable", in which the bubble resonates and incrementally grows, usually in a standing wave field; and 'transient', in Which the bubble expands and implodes all within one cycle of a standing or travelling sound wave. A travelling P wave should be an efficient stimulus of transient cavitation, although long trains or strong-motion P waves may induce Stable cavitation SL as well. The observed SL spectrum in water has a peak at 310 nm (in the ultraviolet), arising from the return to the ground state of the excited hydroxyl radical (OH); there is also a poorly understood continuum throughout the visible waveband. A pure water SL spectrum will appear blue to bluish-white, but the but the presence of dissolved salts or other impurities can appreciably alter the basic aqueous spectrum(6), so that yellow or red may predominate. SL has been generated in the laboratory with ultrasonic pressure amplitudes of 1-2 bar (0. 1-0.2 MPa)', corresponding roughly to an energy density in the ambient fluid of 10-20 erg cm-3. Whether SL is a viable mechanism for EQLs hinges on the question of whether it is reasonable that P waves of sub audible frequency can supply this energy density in water. The density of the kinetic energy, e (per unit volume), induced in the transmission medium by one cycle of an advancing seismic wavefront is a standard result in seismology(7) and is given by 2 2 e =3D 2(Pi) * p *(Ao/to) where "p" is the density of the medium and "Ao" and "to" are the displacement amplitude and period respectively of the seismic wave. Conservatively estimated values for "Ao" of 1-10 cm and "to" of 0.1-1.0 s may be obtained from the strong ground motion recordings of earthquakes. This yields P-wave energy densities in water of roughly 500-2,000 erg cm-3 at 10-1 Hz and pressure differentials of 1.3-2.7 bar. Thus, seismic P waves are capable of supplying pressure changes and energy densities that exceed the laboratory values that induce SL. Within the water volume irradiated by P waves, EQLs would arise as the integrated light flux from many SL cavitation bursts, all loosely synchronised by the P-wave dilational half-cycles. In the laboratory, SL produces an illuminance of ~10-(8) lumen CM-(2) (ref.8), which is visible to the dark- adapted eye. Thus, to reproduce an illuminance equivalent to moonlight of 10-(4) lumen cm-(2), as reported for EQLs in Japan(9), ~10(4) ultrasonic SL bursts are required in the laboratory. For the much larger P-wave cavitation events (with bubble micrometre range), the same illuminance could arise from a single event. To illuminate a landscape to moonlight brightness from at least several kilometres distance, 10(2) -10(4) individual SL P-wave bursts would be sufficient. A P- wave with a dilational half-cycle wavelength of ~ 1 km is certainly capable of spawning such an SL field. Reports of EQLs for large nocturnal earthquakes are not ubiquitous, but neither are they extremely rare. Selected characteristics relevant to the SL hypothesis that appear in the EQL literature are: (1) distinct blue to bluish-white EQLs reported from coastal Japan(10) and Hawaii(2); (2) extensive EQLs from an onshore alluvial setting(11); (3) numerous accounts of EQLs sighted offshore from California(1), Mexico(11) and other coastal zones; and (4) well-defined, blue and yellow spherical lights in tsunami wavecrests . (Luminescent organisms may be another source of luminescence in tsunami wavecrests(13), but I do not believe that they would create well defined spheres of light.) Natural SL is perhaps not the only mechanism that produces EQLS, but it is able to explain a wide range of the existing reports. The hypothesis predicts that (1) EQLs should not be confined to the immediate fault rupture zone; (2) bodies of water must be present, although it is possible that saturated soil can sustain SL; (3) EOLs are essentially a coseismic phenomenon, which in the absence of strong foreshocks or aftershocks should not be observed before or more than several minutes after the earthquake; and (4) the EQL spectrum should contain a prominent hydroxyl peak at 310 nm (and for sea water(6) a sodium peak at 589 rim). Hence the SL-EQL hypothesis can be tested by means of spectrographic analysis although obtaining an EQL spectrum will not be a trivial undertaking. ARCH C. JOHNSTON Center for Earthquake Research, Memphis State University, Memphis, Tennessee 38152, USA 1. Derr, J. Bull. seis. Soc. Am. 63, 2177-2187 (1973). 2. Lockner, D. A., Johnston, M. J. S. & Byerlee, J. D. Nature 302, 28-33 (1983). 3. Brady, B. T. & Rowell. G. A. Nature 321, 488-492 1986). 4. Barber, B. P. & Putterman, S. J. Nature 352, 318-320 (1991). 5. Suslick, K. s. science 247, 1439-1445 (1990). 6. Suslick, K. S. & Flint, E. B. J. Phys. Chem. 95, 1484 (1990). 7. Kasahara. K. Earthquake Mechanics (Cambridge University Press, (1981). 8. Walton. A. J. & Reynolds, G. T. Adv. Phys. 33, 595-660 (1984). 9. Musya. K. Bull. Earthquake Res. inst. Tokyo univ. 9, 214-215 1931). 10. Terada, T. Bull. Earthquake Res. Inst. Tokyo Univ. 9, 225-255 (1931). 11. Fuller, M. 1. U.S. Geol. Sutv. Bull. 494, 120 (1912). 12. Musya, K. Bull. Earthquake Res. Inst. Tokyo Univ. 10, 666-673 (1932). 13. Terada, T. Bull. Earthquake Res. Inst. Tokyo Univ. 1, 25-35 (1934). _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Report #1 on Taiwan EQ by Willie Lee From: John Lahr lahr@................... Date: Wed, 22 Sep 1999 10:45:04 -0600 (MDT) ------------- Begin Forwarded Message ------------- Date: Wed, 22 Sep 1999 11:27:44 -0500 (CDT) X-Sender: whklee@.................. Mime-Version: 1.0 To: wehz@........................ From: William Lee Subject: Re: Report #1 on Taiwan EQ by Willie Lee Dear WEHZ team members: Attached below is my first report on the Taiwan earthquake based on waveform data I received last night (i.e., the main shock waveform data from the RTD telemetered system, and from the building array at the CWB HQ). You are free to distribute this Report #1. More with tables, waveforms, graphs, and maps will be ready later today. The strong-motion records from near ground zero look great -- up to about 1g PGA. Willie ============================================================= REPORT #1 on the Chi-Chi (Taiwan) Earthquake as of 6 a.m., Sept. 22 Prepared by W. H. K. Lee with seismic data kindly provided by Dr. K. W. Kuo, Director of the Seismology Center, Central Weather Bureau (CWB), Taipei, Taiwan and his staff. A preliminary note was written by Lee on the night of Sept. 20, based on the information received in e-mails from the CWB AutoLocation system. This is the first report based on some seismic waveform data and preliminary results that Lee had received from CWB. More specific reports containing tables, graphs, and maps will be prepared later today. INTRODUCTION A major earthquake occurred near Chi Chi in the Nantou county, Taiwan, on 1:47 a.m., Sept. 21, local time, about 90 miles south of Taipei. The dead toll exceeded 1800 and is mounting, thousands of houses collapsed making more than 100,000 people homeless. It is a major disaster. This big quake generated a wealth of modern digital data for seismology and earthquake engineering, because an extensive six-year, strong-motion instrumentation program for Taiwan was successfully implemented 3 years ago. Reliable hypocenter and magnitude were determined automatically in about 100 seconds (after the earthquake's origin time), and I received this information in an e-mail, several minutes later. Thousands of aftershcoks have been recorded. PGA VALUES NEAR THE EPICENTER Strong-motion records had been retrieved at two stations in the epicentral area (epicentral distance of 8 and 10 km) with the following PGA values. Strong ground motion lasted over 30 seconds. Station TCU078: 0.17 g (vertical), 0.30 g (NS), and 0.44 g (EW). Station TCU129: 0.34 g (vertical), 0.61 g (NS), and 0.98 g (EW). INSTRUMENTATION IN OPERATION In 1990, Professor Ta-Liang Teng of the University of Southern California and Professor Yi-Ben Tsai (now at the National Central University of Taiwan) persuaded the local government to fund an extensive seismic instrumentation program for the urban areas of Taiwan with mostly strong-motion instruments. After 6 years and about $40 million US dollars later, the Seismology Center of the Central Weather Bureau completed the installation in 1996 of: (1) About 700 modern digital accelerograhs in free-field sites, (2) About 50 realtime seismic arrays (up to 60 accelerometers) in representative buildings and bridges, (3) A rapid earthquake information release system based on 60+ telemetered digital accelerographs, and (4) A prototype earthquake early warning system in Hualien. This program was executed by the CWB's Seismology Center under the direction of Dr. T. C. Shin (now Deputy Director-General of CWB). An advisory committee consists of about 10 seismologists and earthquake engineers assisted CWB in the planning of the program and the design of the instrumentation. Cooperative projects with the U. S. Geological Survey (1991-1995), and with the Southern California Earthquake Center (1991-present) greatly accelerated the implementation and the successful operation. Taiwan is a small island, about 8% of the area of California or Japan. With the above instrumentation, Taiwan operates the densest digital strong-motion instruments of the world. For comparison, station spacing of the free-field accelerographs in Taiwan is about 3 km in the metropolitan area (vs a 25-km uniform spacing of K-Net in Japan). The basic design of the realtime strong-motion array system for structures has since been implemented by PG&E for the headquarter building in San Francisco, and is now being implemented in the Millikan Library building of Caltech and in a building at UCLA. CWB's Rapid Earthquake Information Release System (AutoLocation) began operation in March 5, 1996. Continuously telemetered data from 60+ digital accelerographs were automatically processed in a dual PC-based system (for redundancy) in Taipei, using hardware and software designed and implemented in the early 1990's (Lee et al., 1996; Shin et al., 1996). Early results had been published by Teng et al. (1997), and by Wu et al. (1997). REFERENCES Lee WHK, Shin TC and Teng TL (1996). Design and implementation of earthquake early warning systems in Taiwan. Proc. 11th World Conf. Earthq. Eng., Paper No. 2133. Shin TC, Tsai YB, and Wu YM (1996). Rapid response of large earthquake in Taiwan using a realtime telemetered network of digital accelerographs. Proc. 11th World Conf. Earthq. Eng., Paper No. 2137. Teng TL, Wu L, Shin TC, Tsai YB, and Lee WHK (1997). One minute after: strong motion map, effective epicenter, and effective magnitude. Bull. Seism. Soc. Am., vol 87, p 1209-1219. Wu YM, Shin TC, Chen CC, Tsai YB, Lee WHK, and Teng TL (1997). Taiwan rapid earthquake information release system. Seism. Res. Letters, vol 68, p 931-943. ------------- End Forwarded Message ------------- _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: RE: Fireballs From: John Hernlund hernlund@....... Date: Wed, 22 Sep 1999 15:15:57 -0700 (MST) On Wed, 22 Sep 1999, Oguzhan Aydogmus-HRB wrote: > Authoizeds said methane burst.But I thing it's not satisfy. Many coastal areas have what are called "gas clathrates" which are hydrocarbons like methane caged inside a special kind of low density ice structure. They are very unstable however (it is a metastable phase), and any shaking could easily cause the exsolution of the gases. People are trying to find safe ways to mine the stuff, but the technical challenges have not yet been overcome... This has worried some people in regions like the northwestern US where large resevoirs of the stuff are reported to exist. A big cascadia quake could upset it easily. Another interesting thing is that some people attribute dissapearances in the Bermuda Triangle to these gas bursts because they could easily sink a ship or choke a plane engine. John Hernlund E-mail: hernlund@....... WWW: http://www.public.asu.edu/~hernlund/ ****************************************************************************** _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: R: R: Taiwan broadband sensor From: Larry Cochrane cochrane@.............. Date: Wed, 22 Sep 1999 19:52:22 -0700 At 08:51 AM 9/22/99 +0200, you wrote: >Usgs world telemetry at http://aslwww.cr.usgs.gov/Seismic_Data/heli2.htm >I seen your Tato Station event file of Taiwan Quake. Where do you have >downloaded the sac file? > >Francesco Francesco, This is how I receive the data from the USGS. I wrote two command line C programs to do this. One program connects to the USGS using TCP/IP and saves the data received from the USGS server to disk. These files, one for each station I am monitoring, is like the daily record file in SDR except the data received is in mini-seed format. This program runs all of the time as a NT service on my Web server system. I am able to receive data all of the time since I have a full time connection to the Internet with a high speed DSL connection. The second program is used to create PSN formatted event files from the data saved by the other program. On the command line I enter the station ID, start time and how many minutes to save, and the program tries to create the PSN event files. Since the data to the USGS and then to me all use the Internet the reliability is not that great.... I am planning to create a web page similar to the Data Request page at http://www.seismicnet.com/request.html so anyone on the Internet can access the data I am receiving. -Larry Cochrane Redwood City, PSN _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: From: "jeremy t.l." tagrtfly@.......... Date: Thu, 23 Sep 1999 13:37:14 PDT hey i need to get removed from this mailing list temporarily so how do i get removed ________________________________________________________________ Get FREE voicemail, fax and email at http://voicemail.excite.com Talk online at http://voicechat.excite.com _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Ohio 'Hiccup' From: "Rex Klopfenstein, Jr." rklopfen@......... Date: Thu, 23 Sep 1999 20:45:12 -0400 I have just posted a recording of the 2.8 Quake on my website that appears to have occurred just offshore of Cleveland in Lake Erie. Didn't feel anything here, I was sound asleep at 6:02 AM anyway. It actually hasn't been on the news yet, maybe on the 11PM news. -- Rex Klopfenstein, Jr. Bowling Green, OH rklopfen@......... http://www.wcnet.org/~rklopfen _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Ohio 'Hiccup' From: Larry Cochrane cochrane@.............. Date: Thu, 23 Sep 1999 18:59:18 -0700 Rex, Can you send your event file in to the archive system (event@............... so we can look at it with WinQuake? Thanks, Larry Cochrane Redwood City, PSN At 08:45 PM 9/23/99 -0400, you wrote: >I have just posted a recording of the 2.8 Quake on my website that >appears to have occurred just offshore of Cleveland in Lake Erie. >Didn't feel anything here, I was sound asleep at 6:02 AM anyway. It >actually hasn't been on the news yet, maybe on the 11PM news. > >-- >Rex Klopfenstein, Jr. >Bowling Green, OH >rklopfen@......... >http://www.wcnet.org/~rklopfen > > > >_____________________________________________________________________ > >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) Subject: Stable Levitation, web site, with pic's From: meredithlamb@.............. Date: 23 Sep 1999 20:29:13 -0700 Hi All, Not exactly seismic orientated, but perhaps of interest to afew on the list. Robert Lamb forwarded this interesting web site reference. http://www.eden.com/~little/index.html This small group in Austin, Texas, checks out claims from others in relation to "free energy sources", and other things. Therein is some particular brief statements and acouple pictures on a "Stable Magnetic Levitation...without superconductors" The brief web site shows a levitating neodymium magnet, with a large ceramic magnet and acouple cyclindrical sections of bismuth. There is no motors, spinning magnets, electronic circuits, cryogenics or etc., with this device. http://www.eden.com/~little/magnets/lev.html The rough model is a followup from an article in Nature magazine (Vol. 400, 22jul99 p. 323), and from there additional explanations or some clarifications could be likely found. Meredith Lamb Signup for your free USWEST.mail Email account http://www.uswestmail.net _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Ohio 'Hiccup' From: Nick & Sophie Caporossi nickcap@............. Date: Fri, 24 Sep 1999 00:12:50 -0400 Hi Rex: I also think I detected something on about 10:03utc on 9/22/99. It was a small Hiccup, not much to write home about. It indicated it was 392 mile from me. On: >http://quake.wr.usgs.gov/cgi-bin/quake/seismo.nrcan.gc.ca The following was posted. >1999/09/22 10:02:22 41.83N 81.48W 18.0G 2.8MN GSC OHIO, SOUTH SHORE OF LAKE ERIE Nick Caporossi 40.413N 74.390W At 08:45 PM 9/23/99 -0400, you wrote: >I have just posted a recording of the 2.8 Quake on my website that >appears to have occurred just offshore of Cleveland in Lake Erie. >Didn't feel anything here, I was sound asleep at 6:02 AM anyway. It >actually hasn't been on the news yet, maybe on the 11PM news. > >-- >Rex Klopfenstein, Jr. >Bowling Green, OH >rklopfen@......... >http://www.wcnet.org/~rklopfen _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: [Fwd: Advice] From: Edward Cranswick cranswick@........ Date: Thu, 23 Sep 1999 22:28:07 -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". Warren- It has been more than two decades since I have been in graduate school, and I am not very familiar with recent books on the subjects you ask about. The best source of information in my recent experience about these matters is the Public Seismic Network (PSN), and I recommend you check out the following website: . Good luck. -Edward Warren Offutt wrote: > I am interested in studying the > > interpretation of seismograms, and also > > short range (active) seismic subsurface survey techniques > > could you suggest any good text(s) at the undergraduate or graduate level > for either or both of these subjects? > > Thanks in advance for any advice you might be able to provide. > > Warren Offutt, D.E. > W & B Observatory > Cloudcroft, NM 88317 -- 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: Ohio 'Hiccup' From: Edward Cranswick cranswick@........ Date: Thu, 23 Sep 1999 23:15:13 -0600 Rex- I have talked to three members of the Pennsylvania/Ohio media in the last few days about the 1998 Sep 25 Pymatuning Earthquake ( and ), the largest earthquake in the history of Pennsylvania, because they are writing stories about the one year anniversary of the event this Saturday. Your report is a fitting reminder that seismicity is still alive and well in the old Northwest. -Edward "Rex Klopfenstein, Jr." wrote: > I have just posted a recording of the 2.8 Quake on my website that > appears to have occurred just offshore of Cleveland in Lake Erie. > Didn't feel anything here, I was sound asleep at 6:02 AM anyway. It > actually hasn't been on the news yet, maybe on the 11PM news. > > -- > Rex Klopfenstein, Jr. > Bowling Green, OH > rklopfen@......... > http://www.wcnet.org/~rklopfen > > _____________________________________________________________________ > > 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) Subject: Moffett Field, CA Simulation From: DGentry509@....... Date: Fri, 24 Sep 1999 08:20:21 EDT NASA AMES TO HOST COLLAPSED STRUCTURE SIMULATION In observance of Earthquake Preparedness Month, news reporters are invited to participate in a Collapsed Structure Simulation on Wednesday, Sept. 29, at NASA Ames Research Center, Moffett Field, CA. The simulation will be held from 8 a.m. to 4 p.m. PDT at Ames' Collapsed Structure Training Facility, Bldg. N-267, the primary training site for the center's Disaster Assistance & Rescue Team (DART). During a realistic training exercise, reporters will be able to either rescue a victim, portray a victim being rescued, or operate the concrete-breaking tools needed to reach a victim. Since reporters may be crawling through smoke-filled tunnels, basements or rooms with collapsed ceilings, safety equipment and protective clothing will be provided. "This will be an opportunity to make the public aware of what it is like to be in a collapsed structure caused by a disaster, such as a major earthquake," said Robert J. Dolci, Director of Emergency Services at NASA Ames. Santa Clara County disaster officials plan to conduct an earthquake exercise on Oct. 13, four days before the 10th anniversary of the Loma Prieta Earthquake. Reporters will be able to participate in seven one-hour training exercises. Training exercises will be scheduled from 8 a.m. to 9 a.m.; 9 a.m. to 10 a.m.; 10 a.m. to 11 a.m., 11 a.m. to 12 p.m.; 1 p.m. to 2 p.m.; 2 p.m. to 3 p.m. and 3 p.m. to 4 p.m. Reporters wishing to participate in the training exercise should call 650/604-3937 to book a time slot and plan to arrive at least 30 minutes prior to the start of their training exercise in order to don protective gear. "People need to be aware that it takes a large team many, many hours to find and remove a victim," Dolci said. "It can take as many as 70 highly-trained specialists 24 hours or more to remove one person from a collapsed structure." _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: More on Ohio 'Hiccup' From: Nick & Sophie Caporossi nickcap@............. Date: Fri, 24 Sep 1999 09:11:17 -0400 Hi Rex: Me again. On closer inspection of the Ohio event, the hiccup I got was only house noise. My son got early that morning and I attribute the noise to the walking around on the second floor. Nick >Date: Fri, 24 Sep 1999 00:12:50 -0400 >To: PSN-L Mailing List >From: Nick & Sophie Caporossi >Subject: Re: Ohio 'Hiccup' > >Hi Rex: > I also think I detected something on about 10:03utc on 9/22/99. > It was a small Hiccup, not much to write home about. It indicated it was 392 mile from me. > _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: RE: Taiwan earthquake reports and data available on the Web From: John Lahr lahr@................... Date: Fri, 24 Sep 1999 08:16:53 -0600 (MDT) ------------- Begin Forwarded Message ------------- Date: Thu, 23 Sep 1999 21:59:28 -0500 (CDT) X-Sender: whklee@.................. Mime-Version: 1.0 To: wehz@........................ From: William Lee Subject: RE: Taiwan earthquake reports and data available on the Web Dear WEHZ colleagues: I am very pleased to inform you that all seismological data recorded by the Central Weather Bureau (CWB) for the Chi-Chi (Taiwan) earthquake will be made available as soon as practical. Dr. Tony T. C. Shin, Deputy Director of the Central Weather Bureau (and formerly the Director of its Seismology Center) told me that these valuable data belong to the world [for scientific and engineering use]. As a step towards making these data available, a temporary Web site has been established through the courtesy of the United States Geological Survey. Report #1 and Report #2 (containing early aftershock data and two near-source accelerograms) are now posted at: http://caldera.wr.usgs.gov These two near-source accelerograms were retrieved by the CWB staff under great difficulties as roads and communication to the epicentral area had been disrupted by the earthquake. The digital data files for these two near-source accelerograms will be available for download in the next few days. There are over 700 digital accelerographs in the free-field sites (see Figure 2 in Report #2), and about 50 accelerometer arrays in buildings and structures. Please be patience as the CWB staff have been stretched to their limits, and I also need some sleep. Best regards, Willie Lee c.c.: Dr. Tony Shin; Dr. K. W. Kuo; ------------- End Forwarded Message ------------- _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Stable Levitation, web site, with pic's From: John Lahr lahr@................... Date: Fri, 24 Sep 1999 08:34:00 -0600 (MDT) Hi Meredith, On another list I was introduced to static magnetic levitation. There is a link to the demo I built on this page: http://lahr.org/john-jan/handson/ I had this device at the USGS open house and should have shown it to you then! JCLahr _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Ohio Quake From: "Rex Klopfenstein, Jr." rklopfen@......... Date: Fri, 24 Sep 1999 12:29:57 -0400 I just posted the data file to Larry Cochrane's archive http://psn.quake.net -- Rex Klopfenstein, Jr. Bowling Green, OH rklopfen@......... http://www.wcnet.org/~rklopfen _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Stable Levitation, web site, with pic's From: meredithlamb@.............. Date: 24 Sep 1999 10:15:38 -0700 On Fri, 24 September 1999, John Lahr wrote: > > Hi Meredith, > > On another list I was introduced to static magnetic levitation. There > is a link to the demo I built on this page: > http://lahr.org/john-jan/handson/ > > I had this device at the USGS open house and should have shown it > to you then! > > JCLahr Hey John....your web site and and Simon Quellen's site, were just fantastic to review! I never forgot the first time at your then, rented house in Golden, with your magnetic spinning top hovering in the air some 5-6 inches above magnetic b ase...it made the whole group go silent with facination!! I suppose in the back of everyones minds, comes the questions involving using the neodymium magnet as a seismic sensor, or vague environmental magnetic field magnetometer. With it, the questions of maximum and minimum sizes of magnets involved and in particular the allowable mass of the neodymium magnet. Simon Quellens web site, showed a picture of a stable/static neo which: "bobs and spins in the wind from the viewers's breath", which implied some neo/mass allowable movement, from the rest of the "frame structure". Now I wonder if a Hall sensor/s could find some application here; even though the "period" would likely be short period. Sounds kind of far fetched, but, it almost sounds very possible, if for nothing more than a newer and unique approach. Looks like I'll have to thoughly check out your site much more often, in the future.... Thanks for the reply and references; very interesting! Meredith Lamb Signup for your free USWEST.mail Email account http://www.uswestmail.net _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Stable Levitation, web site, with pic's From: The Lahrs JohnJan@........ Date: Fri, 24 Sep 1999 19:07:34 -0600 Hi Meredith, Could you resend me the URL's from your first message on magnetic levitation? I've lost the Email somehow! Thanks, John John C. Lahr 1925 Foothills Road Golden, CO 80402 (303) 215-9913 http://lahr.org/john-jan I am only one, But still I am one. I cannot do everything, and because I cannot do everything, I will not refuse to do the something that I can do. Edward Everette Hale _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Noise From: Doug Crice dcrice@............ Date: Fri, 24 Sep 1999 20:17:04 -0700 Sean (or anybody else), I was chatting with Eric from Kinemetrics to try and figure out what kind of specsmanship they are using to get so much dynamic range from their accelerometer. He said that they use something called a "half octave" for the bandwidth (bandwidth being a necessary component of any noise spec of course) and that this was published in the literature and some sort of a standard. To save me looking all over, can you tell me what a "half octave" is? I was also surprised to hear that they used something called a "noise model" which is supposed to be the median noise of production sensors, which of course means that half the sensors they ship don't meet the spec. Is this "noise model" thing legit? -- 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) Subject: seismology book; diamagnetism From: S-T Morrissey sean@........... Date: Fri, 24 Sep 1999 22:21:43 -0500 (CDT) A recent question about interpreting seismograms: A modern book that is used as a classroom textbook is: "Modern Global Seismology", by Thorn Lay and Terry C. Wallace. Academic Press; 1995; ISBN 0-12-732870-X. It covers the whole range of seismology and solid earth geophysics. There is math and formulas, but it is quite readable, with lots of figures, without deciphering the math. About magnetic leviation: There was an article in PHYSICS TODAY last September about diamagnetism (the magnetism of normally non-magnetic materials). THey use a hugh magnet (that takes 20 000 amperes at several megawatts) to levitate things like blobs of water and a live frog in a 20 Tesla specially shaped field (a common Alnico magnet is about 1 Tesla). Since levitation is in fact balancing gravity, and gravity is changing from 50 to 300 microgals daily due to earth tides, continuous fine-tuning of the field is necessary. The diamagnetism is due to the forces on electrons in the material that when immersed in the intense magnetic field become weak magnets of the order of 1 gauss. THey report that the 1 gauss frog is quite confused but otherwise unharmed. Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Precursors From: EK kerls@...... Date: Fri, 24 Sep 1999 22:31:59 -0500 Dear jerry; If you are interested in understanding earthquakes precursors, over the weekend I am going to post on our web-page NOAA satellite pictures of proof of the precursors that we am talking about. These pictures will start three [ 3 ] satellite pictures in advance,[ But these pictures are a composite of three days each so we start on 09/11/99, before the Taiwan earthquake of 09/20/99 so that you can follow these precursors to the fault. This is not a precise means to do this but it does show proof of theses precursors. I will also show the precursors on the earthquake in Turkey. Maj. Edward E. Kerls A.R. [ KD5ELB ] _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Noise From: Mark Robinson other@............... Date: Sat, 25 Sep 1999 17:33:00 +1200 Hi Doug, Octaves come from music. A note one octave higher than another is twice the frequency, or a piece of string half as long ;) consequently half an octave is a number which I cant work out in my head being half of double. This aint a linear thing, and I am no mathematician. Lets just say it is the distance from say middle C to F sharp, but then I am no musician either. regards mark > To save me looking all over, can you tell me what a "half octave" is? _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Precursors From: Canie canie@........... Date: Fri, 24 Sep 1999 22:41:37 -0700 what web site is that ? Canie At 10:31 PM 9/24/99 -0500, you wrote: >Dear jerry; > If you are interested in understanding earthquakes precursors, >over the weekend I am going to post on our web-page NOAA satellite >pictures of proof of the precursors that we am talking about. > These pictures will start three [ 3 ] satellite pictures in >advance,[ But these pictures are a composite of three days each so we >start on 09/11/99, before the Taiwan earthquake of 09/20/99 so that you >can follow these precursors to the fault. This is not a precise means to >do this but it does show proof of theses precursors. I will also show >the precursors on the earthquake in Turkey. > > Maj. Edward E. Kerls A.R. [ KD5ELB ] > > >_____________________________________________________________________ > >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) Subject: Re: Noise From: "Anders Heerfordt" aheerfor@...... Date: Sat, 25 Sep 1999 07:45:45 +0200 > consequently half an octave is a number which I cant work out in my head being half of double. < A half octave is bounded by two frequencies of which the higher is the lower times the square root of two. Regards,Anders _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Precursors From: Canie canie@........... Date: Fri, 24 Sep 1999 22:50:35 -0700 Sorry - I found the web site... I remember looking at that - I am within 1 mile of a fault line so I can't help with your project. Canie At 10:31 PM 9/24/99 -0500, you wrote: >Dear jerry; > If you are interested in understanding earthquakes precursors, >over the weekend I am going to post on our web-page NOAA satellite >pictures of proof of the precursors that we am talking about. > These pictures will start three [ 3 ] satellite pictures in >advance,[ But these pictures are a composite of three days each so we >start on 09/11/99, before the Taiwan earthquake of 09/20/99 so that you >can follow these precursors to the fault. This is not a precise means to >do this but it does show proof of theses precursors. I will also show >the precursors on the earthquake in Turkey. > > Maj. Edward E. Kerls A.R. [ KD5ELB ] > > >_____________________________________________________________________ > >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) Subject: Re: seismology book; diamagnetism From: Karl Cunningham karlc@....... Date: Sat, 25 Sep 1999 00:06:56 -0700 Diamagnetism has been used for years as a method to achieve very fine adjustments in the inductance of coils. In RF work, a coil is wound with a diameter of perhaps 1/4" and a length of maybe 1". Instead of using the typical ferrite core, a brass (diamagnetic) core is used. When adjusted in and out of the coil, the brass affects the inductance of the coil, but only very slightly and in the opposite sense than that of ferrite. Inserting the core reduces the inductance. Charts can be found of the permeability of diamagnetic materials, which is less than one. Can't remember where I've seen them, and I don't remember frogs being listed. Karl Cunningham La Mesa, CA. PSN Station #40 karlc@....... _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Noise From: Doug Crice dcrice@............ Date: Sat, 25 Sep 1999 07:56:20 -0700 Anders Heerfordt wrote: > > consequently half an octave is a number which I cant work out in my head > being half of double. > < > A half octave is bounded by two frequencies of which the higher is the lower > times the square root of two. > Regards,Anders > Thanks, I actually knew what an octave was, but also couldn't do the math to intuit a "half-octave". In hindsight, the square root of two is an obvious choice. Now I understand how they can claim a dynamic range of 155 dB. If you make the bandwidth small enough, you can get big numbers. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: seismology book; diamagnetism From: Bob Fryer bfryer@............ Date: Sat, 25 Sep 1999 08:38:05 -0700 Bismuth is the strongest diamagnetic material, with lead as one of the weaker diamagnetics. Jerry Gallimore used bismuth in his (1975) room-temperature superconductor, to eject the magnetic field and channel the interfering energy, possibly gravity. He found that there is a halo-shaped field of gravity around the midpoint of a bar magnet. Bob Fryer >Diamagnetism has been used for years as a method to achieve very fine >adjustments in the inductance of coils. In RF work, a coil is wound with a >diameter of perhaps 1/4" and a length of maybe 1". Instead of using the >typical ferrite core, a brass (diamagnetic) core is used. When adjusted in >and out of the coil, the brass affects the inductance of the coil, but only >very slightly and in the opposite sense than that of ferrite. Inserting >the core reduces the inductance. > >Charts can be found of the permeability of diamagnetic materials, which is >less than one. Can't remember where I've seen them, and I don't remember >frogs being listed. > >Karl Cunningham ----- earthquake WARNING research ----- --- animals, people, scientific evidence --- --- http://www.teleport.com/~bfryer --- _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Bruce Bolt Article From: "Erich Kern" ekern@......... Date: Sat, 25 Sep 1999 13:41:43 -0700 Hi All, Bruce Bolt has an Op-Ed piece on quake prediction in this past Thursday's Wall St. Journal, page A22. In a nutshell, precursors such as they are, are not reliable and the most effective path is seismic hazard mitigation through well engineered structures. A large amount of strong motion data is essential to the engineering process. Bolt adds that the U.S. and other quake prone areas need more strong motion data networks to enlarge the data base of how quakes effect structures. Not only buildings but bridges, highways and other infrastructure. Erich Kern Murrieta, CA ********************************************************* Please visit our web site at: http://fqs.dconn.com ********************************************************* _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Copies of B. Bolt article From: "Erich Kern" ekern@......... Date: Sat, 25 Sep 1999 14:19:49 -0700 I'd be willing to fax anyone who wants it, a copy of Bruce Bolt's article. Can't send by email...no scanner, and it's not on the WSJ web site. Send your fax number to me, ekern@......... not to the list please. Erich Kern _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Diamagetism / coil tuning / seismometers From: "Charles R. Patton" charles.r.patton@........ Date: Sat, 25 Sep 1999 15:40:21 -0700 First: Karl, sorry, but diamagnetism may be present, but the main effect of RF tuning with brass slugs is due to the shorted turn effect of the slug. As the slug is brought into the coil it couples a shorted turn to the coil, thus lowering its effective primary inductance, thereby causing the resonance frequency to rise. The key is to use a very conductive material so the Q doesn=92t take too big a hit. That is the main drawbac= k to the slug, Q has to go down from the coil=92s Q alone, conversely, the use of ferrite can be accompanied by an increase in Q (as long as the loss of the ferrite is low in comparison to the loss in the coil). So decreasing Q can be OK in an oscillator, but generally is at odds with tuned filter type applications where a constant BW is desired. So to maintain constant BW, Q has to increase in proportion to the frequency (or inductance). Second: Meredith Lamb asked, =93=85questions involving using the neodymium magnet= as a seismic sensor=85=94 I knew for a long time that a carbon rod had been incorporated in a seismic sensor but I didn=92t know much more until recently I finally found the report with the construction details. ARPA sponsored Arthur D. Little company to design a borehole seismic sensor around 1967-69. The final report is titled: DEVELOPMENT OF A THREE-AXIS LONG-PERIOD SEISMOGRAPH Report no. C-69429. It=92s a 75 page report with many of the constructio= n details. It used a 2.5=94 by 0.086=94 dia. carbon rod approx. 0.8 gms in= weight suspended diamagnetically as the seismic mass. They sensed the position photoelectrically. The sensor itself was essentially flat from DC to 0.5 Hz. With filters they tailored the response to be flat (3dB) from 0.02 to 0.07 Hz. teleseimic events of mb <=3D 5 were consistently recorded. You can order it from NTIS at 800-553-6847 for $34. (It=92s public domain, and if you want a copy from me I=92ll do the whole thing for $10, US postage included.) Sincerely, Charles R. Patton charles.r.patton@........ _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Diamagetism / coil tuning / seismometers From: meredith lamb mlamb1@.......... Date: Sat, 25 Sep 1999 17:17:34 +0000 "Charles R. Patton" wrote: > Second: > Meredith Lamb asked, “…questions involving using the neodymium magnet as > a seismic sensor…” > I knew for a long time that a carbon rod had been incorporated in a > seismic sensor but I didn’t know much more until recently I finally > found the report with the construction details. ARPA sponsored Arthur > D. Little company to design a borehole seismic sensor around 1967-69. > The final report is titled: > DEVELOPMENT OF A THREE-AXIS LONG-PERIOD SEISMOGRAPH > Report no. C-69429. It’s a 75 page report with many of the construction > details. It used a 2.5” by 0.086” dia. carbon rod approx. 0.8 gms in > weight suspended diamagnetically as the seismic mass. They sensed the > position photoelectrically. The sensor itself was essentially flat from > DC to 0.5 Hz. With filters they tailored the response to be flat (3dB) > from 0.02 to 0.07 Hz. teleseimic events of mb <= 5 were consistently > recorded. You can order it from NTIS at 800-553-6847 for $34. (It’s > public domain, and if you want a copy from me I’ll do the whole thing > for $10, US postage included.) > > Sincerely, > Charles R. Patton > charles.r.patton@........ > Charles, This news is absolutely amazing to me. I would almost suspect the construction details are pretty much beyond any amateur level to accomplish; but they would sure be very, very interesting to see. In a way, I thought diamagnetic suspension only occurried in the 1990's....but, from John Lahr's site and reference followup, there is some implied reference (unaccessible for the moment), with dates going back to the 1940's. Thanks so much for the information. Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: quake in progress From: "Francesco" franuc@...... Date: Sun, 26 Sep 1999 02:30:01 +0200 Large S and surface wave is coming. Taiwan aftershock? ~6.5 Francesco _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: TAIWAN From: "Francesco" franuc@...... Date: Sun, 26 Sep 1999 02:39:52 +0200 Now, L e R w. Taiwan, Mb 6.4 Francesco _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: more on diagmagnetism From: S-T Morrissey sean@........... Date: Sun, 26 Sep 1999 00:37:24 -0500 (CDT) Some further info from the PHYSICS TODAY (9/98) article, since there seems to be further interest: Diamagnetism was first discovered by Michael Faraday in 1846, but he and Lord Kelvin assumed that there never would be magnets strong enough for it to be experimented with. In 1939 graphite beads were levitated (graphite has the largest ratio of susceptibility to density of diagmagnetics). By 1947 superconductors got into the game. But as was mentioned, it wasn't until 1991 that intense enough controllable fields could levitate organics and water. A diagmagnetic tiltmeter was also made by A.D.Little using principles similar to their seismometer. (Simon, I., et al, "Sensitive tiltmeter utilizing a diagmagnetic suspension", Reviews of Scientific Instruments, 39, 1666-1671, 1968). It used a graphite rod suspended horizontally in the long gap of a large horseshoe shaped permanent/electromagnet with cleverly crafted pole shapes. It sensed the rod position optically, which limited the resolution; but because of the sensitivity of the levitation, it could detect earth tides at a tilt of 10^-9 radian. A major problem was the change in the strength of the magnet with temperature. Only a few were built and tested. Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Diamagetism / coil tuning / seismometers From: Karl Cunningham karlc@....... Date: Sun, 26 Sep 1999 07:21:27 -0700 Charles -- Thanks for setting me straight. I had heard it was diamagnetism years ag= o, but your explanation makes more sense. Karl At 03:40 PM 9/25/99 -0700, you wrote: >First: >Karl, sorry, but diamagnetism may be present, but the main effect of RF >tuning with brass slugs is due to the shorted turn effect of the slug. >As the slug is brought into the coil it couples a shorted turn to the >coil, thus lowering its effective primary inductance, thereby causing >the resonance frequency to rise. The key is to use a very conductive >material so the Q doesn=92t take too big a hit. That is the main drawba= ck >to the slug, Q has to go down from the coil=92s Q alone, conversely, the >use of ferrite can be accompanied by an increase in Q (as long as the >loss of the ferrite is low in comparison to the loss in the coil). So >decreasing Q can be OK in an oscillator, but generally is at odds with >tuned filter type applications where a constant BW is desired. So to >maintain constant BW, Q has to increase in proportion to the frequency >(or inductance). _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Diamagetism / coil tuning / seismometers From: TMrvos@....... Date: Sun, 26 Sep 1999 11:38:58 EDT You people do not say a word about what you are doing to beginners, likre me. So far everything has been like Greek. At least I know a couple of words in Greek. Primers ? _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Questions (was Re: Diamagetism / coil tuning / seismometers) From: Karl Cunningham karlc@....... Date: Sun, 26 Sep 1999 09:50:43 -0700 Please let us know what you would like to know about. Many of the discussions on this list get rather technical, but many are not. Ask some questions, no matter how elementary. If it relates to seismology, I'm sure there will be someone willing to answer. Karl Cunningham La Mesa, CA. PSN Station #40 karlc@....... At 11:38 AM 9/26/99 EDT, you wrote: >You people do not say a word about what you are doing to beginners, likre me. >So far everything has been like Greek. At least I know a couple of words in >Greek. Primers ? _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: ask questions From: S-T Morrissey sean@........... Date: Sun, 26 Sep 1999 12:41:48 -0500 (CDT) I agree with Karl. Please don't hesitate to ask. There is an archive of all our arcane ramblings on the PSN site, if you can muster enough "greek" (or is it seismo-geek) to wade through it. I maintain several directories of my contributions, so it is not a major task to search and rehash an old topic to be appropos to a new discussion. And, if you are concerned, the latest discussions about diamagnetism is an interesting curiosity that has little to do with practical seismology or instrumentation. THe point is that a seismometer needs to have an inertial mass that is suspended delicately so that it does not move exactly as the ground moves. THe instrument somehow detects the relative motion between the suspended mass and the ground. THe more delicate the suspension is, the more potentially sensitive the detection of ground motion is. So a mass that is levitated by a magnet can be very sensitive because of the near-instability of the levitation. However, diagmagnetic levitation has not resulted in a practical seismometer, even after some intense professional efforts. ' Regards, Sean-Thomas _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: A Sunday levitating neodymium From: meredithlamb@.............. Date: 26 Sep 1999 19:32:57 -0700 Hi All, Lee Ann and I were invited over to John and Jan Lahr's to explore stable/static diagmagnetic levitation today. John has built afew devices, and we used acouple to test out a variety of neodymium magnets of various sizes and shapes; and also a variety of graphite/carbon DC motor commutator brushes, for their effects. While we primarily tried a number of brushes, we were also easily able to levitate about 5 different neodymium magnets of different shapes and sizes relatively easily. My preconception of difficulty in adjustments went out the window. Thus far, the magnet size limit seemed to be having enough diagmagnetic material to cover above and below the magnets. The largest piece was about 3/4" long by about 3/8's" wide, by around 1/16" thick. It was a most interesting afternoon. I whomped up a fast web page for those interested in diagmagnetics; but without alot of details. http://www.users.uswest.net/~mlamb1/index.html Thanks John and Jan for all the effort and demonstrations, it was very, very interesting. It doesn't seem that long ago, that the top science news was levitating a magnet on a cyrogenic supercooled magnet device....one doesn't need that fancy equipment. Meredith and Lee Ann Lamb Signup for your free USWEST.mail Email account http://www.uswestmail.net _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Student Question... From: "Jan D. Froom" froom@............. Date: Mon, 27 Sep 1999 15:27:18 -0700 In working with my kids at SVJH in Gilroy, I had one student ask the following: He was doing an experiment to determine the amount of iron in the sand at various beaches. He noted that sand from a beach in the state of Washington had about 5 times as much iron as one from Santa Cruz, CA. His conclusion was that the closer you get to the N or S pole, the stronger the magnetic field, and that's why there is more iron in the sand the further north you go. So what do I tell him..... Thanks Jan _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Student Question... From: AHrubetz@....... Date: Mon, 27 Sep 1999 20:28:12 EDT The amount of iron in the beach sands have no relationship to magnetic north as to origin, but rather are a function of the iron content of the igneous, sedimentary, or metamorphic rocks that outcrop or subcrop in the general vicinity of the beach. When the rocks are decomposed, iron and other heavy minerals originally contained in the rock are found along with the silica sands. Rip tides and current action might move the heavy minerals away from the area of origination, but they should not move too far away, relatively speaking, because of their high specific gravity relative to that of water. Al Hrubetz _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Student Question... From: "Kenneth J. De Nault" denault@....... Date: Mon, 27 Sep 1999 20:05:35 -0500 I would commend the student for his hypothesis and ask him to propose some method for testing his hypothesis, such as examining the iron content of sand from Alaska. You might also ask him to make a prediction concerning the iron content of sands as one goes toward the south pole. I would not tell him he is "wrong" but would encourage him to be a scientist. All of us "scientists" have proposed "wrong" hypothesis. Ken De Nault. P.S. The "iron" content is most probably the mineral magnetite. This is a dense, iron oxide mineral whose concentration is a function of many factors, among which is availability in the source rock, the energy of the transport mechanism, and the energy of the depositional environment. As a dense mineral, it tends to be concentrated by the removal of the less dense, and generally much more abundant, silicate minerals. _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Student Question... From: Robert Mathieson rmathieson@.......... Date: Mon, 27 Sep 1999 20:08:34 -0500 The source of the iron in the Washington beaches is probably from the extensive basalt lava flows in the northwestern USA. Basalt is a mafic rock composed mostly of iron and magnesium silicates. There are many fewer mafic rocks inland from Santa Cruz. At 03:27 PM 9/27/99 -0700, you wrote: >In working with my kids at SVJH in Gilroy, I had one student ask the >following: > >He was doing an experiment to determine the amount of iron in the sand >at various beaches. He noted that sand from a beach in the state of >Washington had about 5 times as much iron as one from Santa Cruz, CA. >His conclusion was that the closer you get to the N or S pole, the >stronger the magnetic field, and that's why there is more iron in the >sand the further north you go. > >So what do I tell him..... Thanks Jan > > >_____________________________________________________________________ > >Public Seismic Network Mailing List (PSN-L) > >To leave this list email listserver@.............. with the body of the >message: leave PSN-L > Robert Mathieson Culver-Stockton College Canton, MO 63435 (217)231-6000 rmathieson@.......... _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: ES-SSA99 From: Dick Webb dwebb2@.............. Date: Mon, 27 Sep 1999 21:21:02 -0400 The Eastern Section of the SSA is having their annual meeting in Memphis in October. It's a centrally located city and I was wondering if any PSN members are planning to attend. They have meeting information at ceri.memphis.edu and seismosoc.org Hope to see you there! Dick Webb Raleigh, NC _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: A Sunday levitating neodymium From: "fxmurphy@............" fxmurphy@.................... Date: Mon, 27 Sep 1999 21:43:15 -0400 Very nice it looks like you had alot of fun! I too tried on sunday but did not have alot of luck finding any diagmagnetic material. I tried melting some non lead fishing lures, but I think they were made of mostly tin. What happened was the neodymium magnet would jump from top to bottom, very slowly but I could not stabilze it. So I guess I am going to have to scrounge for some carbon rod. Would like to hear more about finding a good source of diagmagnetic material. Thanks Francis > It was a most interesting afternoon. I whomped up a > fast web page for those interested in diagmagnetics; > but without alot of details. > > http://www.users.uswest.net/~mlamb1/index.html > > Thanks John and Jan for all the effort and demonstrations, > it was very, very interesting. It doesn't seem that long > ago, that the top science news was levitating a magnet on > a cyrogenic supercooled magnet device....one doesn't need > that fancy equipment. > > Meredith and Lee Ann Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: A Sunday levitating neodymium From: meredithlamb@.............. Date: 27 Sep 1999 21:04:56 -0700 On Mon, 27 September 1999, "fxmurphy@............" wrote: > > > Very nice it looks like you had alot of fun! > > I too tried on sunday but did not have alot of luck finding > any diagmagnetic material. I tried melting some non lead fishing > lures, but I think they were made of mostly tin. Haven't worked with bismuth myself. According to what I have read busmuth reloading shot, can be melted on a typical stove. Was this the case? Or, blowtorch high temperature melting? > > What happened was the neodymium magnet would jump from top > to bottom, very slowly but I could not stabilze it. It could be that your adjustment thread on the upper magnet is too coarse...if ? you actually had bismuth? One has to slow down and back up the magnet if the neo jumps up in the sandwich of graphite/bismuth. Sometimes, it a matter of fine adjustment. > So I guess I am going to have to scrounge for some carbon rod. > > Would like to hear more about finding a good source of > diagmagnetic material. With my 4 day experience...ha....I frankly don't know of any commercial outlet for graphite, at least any one, which sells the stuff cheaply. Maybe Mcmaster-carr has carbon rods, but even the smallest diameter stuff is expensive for what they give you....and....theres no guarantee its even diagmagnetic at all. Here in Denver, the only place I found some, was a local surplus outlet (general, but mostly mechanical, not electronics), and they had roughly 50-60 variety shapes, all jumbled together. I picked up a variety and took them home, for testing, using a simple string to a beam balance about 8" long, with a magnet on each end. Bringing the carbon/graphite, close to the magnet on one end, it will either be repelled slightly, or it will be attracted to the magnet, or nothing will happen. Another less sensitive method is using 1/2" scotch tape, about 4-5" long, or longer, and hanging it from like a overhead cabinet in the kitchen. Attach the test carbon, bring the magnet close (this works better with a larger neo magnet than the small neos like at Radio Shack). One could also just hang it on string also... Either method, theres a very limited range of motion on either the magnet or test carbon, probably less than 1/8" for the scotch tape method, and higher for the torsion/beam approach. The real message with finding carbon is that its a search, find, test approach. Old motor carbon brushs, seem to be the most common to me. I wouldn't want to get into old batterys for the electrodes. Perhaps motor repair shops (probably scarce anymore). Junkyards may have old DC motors, but if you have to buy the motor, I'd look elsewhere. Look for the blackest carbon brushs. Forget the grayish black, copper colored, or even the silvery appearance stuff...too much impurities I would think. Again its a shotgun approach, and will cost money to acquire even test pieces, that may or may not work. The size of the 2 carbons that work, will have to fit the neo you are trying to float, and you will have to find something to use as spacers. I'd also hit up electronic surplus stores, most have a variety of older equipment, and I'd guess that perhaps a minority would have "some" old carbon rods or carbon brushs. I'd probably have a better idea of source, but 4 days of acquantance with the subject, doesn't yield any known (guaranteed)commercial source yet. I've checked on the net mind you, but nothing found. Failing that search for graphite...there is net sources/references for bismuth gun reloading shot, but the purity is in question? Some people like it better, some don't... I hear alot of sporting gun shots could have loaded shotgun shells with the stuff; but I really wouldn't want to mess with that. http://www.bismuth-notox.com The above site gives a local search function for your area. http://www.precisionreloading.com/index.html The above site sells direct; credit card, but the quanity (7 pounds) at some $78.00; is a wee bit too high priced for what you would use. Stable/static levitation devices can be bought ready made, at probably a variety of sources. I only web address I have handy is this: http://www.physics.ucla.edu/marty/diamag/lev4sale.html Two models, one for $49, and the other is $69, unless the price went up. It might be cheaper in the long run to buy...rather than homebrew. Of course, theres the challenge in making your own...ha.... Maybe in time, I'll have more data.... Meredith Lamb Signup for your free USWEST.mail Email account http://www.uswestmail.net _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Diamagnetic materials From: "Charles R. Patton" charles.r.patton@........ Date: Mon, 27 Sep 1999 10:27:33 -0700 A quick question/thought for diamagnetic materials (or in particular carbon). I know you have been playing with carbon brushes, what about carbon rods from a welding supply? Usually they are covered with a copper coat, but the copper peels off easily and a 3/16 dia piece I played with is obviously diamagnetic. The other carbon rod source is the old fashioned dry cell =96 not alkaline =96 but carbon/zinc. Pick yo= ur battery for the size rod you want. The main question I had was, if you took several rods from a source such as above, how about just laying them down, next to one another and hot melt gluing them together, i.e., form a plate out of rods? Would this be sufficient for the diamagnetic plates? Charles R. Patton _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: A Sunday levitating neodymium From: Edward Cranswick cranswick@........ Date: Mon, 27 Sep 1999 22:37:37 -0600 Meredith- Belatedly checked out your website which graphicly (graphitely?) brought home to me that I, in my techno-myopia, have blithely missed this whole business of diagmagnetic phenomena which has blossomed in front of me on the PSN-L: why be here and now when I can be in Turkey 5 weeks ago? I'll grab John in the hall and get him to force-feed me on magnetic developments; the human brain is still the best random-access device around. -Edward PS. I didn't know you guys were so religous on Sundays. meredithlamb@.............. wrote: > Hi All, > > Lee Ann and I were invited over to John and Jan Lahr's > to explore stable/static diagmagnetic levitation today. > John has built afew devices, and we used acouple to > test out a variety of neodymium magnets of various > sizes and shapes; and also a variety of graphite/carbon > DC motor commutator brushes, for their effects. > > While we primarily tried a number of brushes, we were > also easily able to levitate about 5 different neodymium > magnets of different shapes and sizes relatively easily. > My preconception of difficulty in adjustments went out > the window. Thus far, the magnet size limit seemed to > be having enough diagmagnetic material to cover above > and below the magnets. The largest piece was about > 3/4" long by about 3/8's" wide, by around 1/16" thick. > > It was a most interesting afternoon. I whomped up a > fast web page for those interested in diagmagnetics; > but without alot of details. > > http://www.users.uswest.net/~mlamb1/index.html > > Thanks John and Jan for all the effort and demonstrations, > it was very, very interesting. It doesn't seem that long > ago, that the top science news was levitating a magnet on > a cyrogenic supercooled magnet device....one doesn't need > that fancy equipment. > > Meredith and Lee Ann Lamb > > > > Signup for your free USWEST.mail Email account http://www.uswestmail.net > > _____________________________________________________________________ > > 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) Subject: Re: Diamagnetic materials From: meredithlamb@.............. Date: 27 Sep 1999 22:20:01 -0700 Charles patton, Both the dry cell battery rod (carbon) source, and the welding carbon rod approachs sound good as possible diamagnetic material. I didn't know welding carbon rods were often coated with copper, this could be useful in damping in itself, as is, for other schemes, Presuming either source yields the right stuff, of course. Wonderful i dea to check on...thanks Charles. As for laying the rods side to side, I doubt it would work (I haven't tried that), but the carbon/graphite I've seen barely floats above the graphite, which has only a weak field. I'am guessing, that the hills and valley in such an arrangement, could also tilt the floating neo, and snag all over the place. Of course, one could try grinding, filing down 1/2 the surface for a smooth "platform/surface", but with the frail nature of carbon, it could be very difficult to do. Another approach might be chopping up the carbon into thin sections and jaming them together vertically, but they would need to be smoothed I'am sure at the "floating surface". What effect all the openings would have, compared to a solid surface is unknown; particularly for the top layer nearest the overhead magnet. Plugging the carbon pieces gingerly into a drill press head, turning on, and using a hand held file could smooth the surface/s also. ************ Actually the 68 pieces that were mentioned earlier, showed a wide variation in diamagnetic properties. Probably a indication of the manufacturer using any old carbon to make their product. Whether welding manufacturers are more stringent; I wouldn't know. This was one piece that had clear markings for a certain mfg, and production # on 58 of the 68 pieces. I should also mention in my carbon brush collecting, the majority of the total, were no good. The assortment I got on saturday, only 2 out of the odd 15 varietys, were diamagnetic. The "68" mentioned, were collected on Monday, of one of the two known "good ones", that luckily they had a quanity on. Again, thanks for the suggestions...they could pan out very well. Thanks, Meredith Lamb Signup for your free USWEST.mail Email account http://www.uswestmail.net _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: A Sunday levitating neodymium From: John Hernlund hernlund@....... Date: Mon, 27 Sep 1999 22:16:39 -0700 (MST) Be careful with the Bismuth! It is far worse for you than lead... John Hernlund E-mail: hernlund@....... WWW: http://www.public.asu.edu/~hernlund/ ****************************************************************************** _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: A Sunday levitating neodymium From: meredithlamb@.............. Date: 27 Sep 1999 22:28:44 -0700 On Mon, 27 September 1999, Edward Cranswick wrote: > -Edward > PS. I didn't know you guys were so religous on Sundays. > > Edward, Very good humor edward.... "graphitely"...ha. Sure glad you didn't spell "religous", with the other version of: "religious"....otherwise, it may not be looked upon with favor in some churches...ha. Meredith Lamb Signup for your free USWEST.mail Email account http://www.uswestmail.net _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: A Sunday levitating neodymium From: "Erich Kern" ekern@......... Date: Mon, 27 Sep 1999 22:56:55 -0700 John, You've not heard of Bismuth enemas then. For lower GI fluoroscope exams. Can't be too toxic then can it? Erich -----Original Message----- From: John Hernlund To: PSN-L Mailing List Date: Monday, September 27, 1999 10:27 PM Subject: Re: A Sunday levitating neodymium Be careful with the Bismuth! It is far worse for you than lead... John Hernlund E-mail: hernlund@....... WWW: http://www.public.asu.edu/~hernlund/ ****************************************************************************** _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: A Sunday levitating neodymium From: jmhannon@.................... Date: Tue, 28 Sep 1999 07:29:47 -0500 The reason bismuth shot and fishing weights are avaliable is that they are a less toxic subsitute for the lead shot and weights. Jim Hannon John Hernlund on 09/28/99 12:16:39 AM Please respond to PSN-L Mailing List To: PSN-L Mailing List cc: Subject: Re: A Sunday levitating neodymium Be careful with the Bismuth! It is far worse for you than lead... John Hernlund E-mail: hernlund@....... WWW: http://www.public.asu.edu/~hernlund/ ****************************************************************************** _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: A Sunday levitating neodymium From: Warner warlin@.......... Date: Tue, 28 Sep 1999 06:27:08 -0700 (PDT) On Mon, 27 Sep 1999, Erich Kern wrote: > John, > You've not heard of Bismuth enemas then. For lower GI fluoroscope exams. Can't > be too toxic then can it? > Erich > Weren't those _barium_?? > > -----Original Message----- > From: John Hernlund > To: PSN-L Mailing List > Date: Monday, September 27, 1999 10:27 PM > Subject: Re: A Sunday levitating neodymium > > > Be careful with the Bismuth! It is far worse for you than lead... > > John Hernlund > E-mail: hernlund@....... > WWW: http://www.public.asu.edu/~hernlund/ > > ****************************************************************************** > > > _____________________________________________________________________ > > 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) Subject: Re: A Sunday levitating neodymium From: jmhannon@.................... Date: Tue, 28 Sep 1999 08:48:09 -0500 They probably are barium. At least that is what I had. However a bismuth compound is the active ingredient in PeptoBismo and bismuth compounds are used to treat a number of GI problems. Bismuth is also used extensively in cosmetics. Jim Hannon Warner on 09/28/99 08:27:08 AM Please respond to PSN-L Mailing List To: PSN-L Mailing List cc: Subject: Re: A Sunday levitating neodymium On Mon, 27 Sep 1999, Erich Kern wrote: > John, > You've not heard of Bismuth enemas then. For lower GI fluoroscope exams. Can't > be too toxic then can it? > Erich > Weren't those _barium_?? > > -----Original Message----- > From: John Hernlund > To: PSN-L Mailing List > Date: Monday, September 27, 1999 10:27 PM > Subject: Re: A Sunday levitating neodymium > > > Be careful with the Bismuth! It is far worse for you than lead... > > John Hernlund > E-mail: hernlund@....... > WWW: http://www.public.asu.edu/~hernlund/ > > ****************************************************************************** > > > _____________________________________________________________________ > > 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) Subject: Re: Student Question... From: angel rodriguez angel@............ Date: Tue, 28 Sep 1999 09:31:48 -0400 Hello Jan, Monday, September 27, 1999, 6:27:18 PM, you wrote: JDF> In working with my kids at SVJH in Gilroy, I had one student ask the JDF> following: JDF> He was doing an experiment to determine the amount of iron in the sand JDF> at various beaches. He noted that sand from a beach in the state of JDF> Washington had about 5 times as much iron as one from Santa Cruz, CA. JDF> His conclusion was that the closer you get to the N or S pole, the JDF> stronger the magnetic field, and that's why there is more iron in the JDF> sand the further north you go. JDF> So what do I tell him..... Thanks Jan JDF> _____________________________________________________________________ JDF> Public Seismic Network Mailing List (PSN-L) JDF> To leave this list email listserver@.............. with the body of the JDF> message: leave PSN-L Some of the beaches in Panama are almost totaly iron, on hot days you can get blisters running across the beach to the sea. Maybe if there is time the studen can correspond with other student via email and either get samples from other beaches or get the other student to do the experimet and send the results. Warmly, Angel angel@............ _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Diamagnetic materials (more) From: "Charles R. Patton" charles.r.patton@........ Date: Tue, 28 Sep 1999 20:27:03 -0700 I=92ve been checking on further sources of carbon and this is what I have= found so far. McMaster Carr (or at least my =9293 catalog) has both plai= n and copper coated welding carbons up to =BE=94 in diameter and very inexpensive. They also sell blocks of carbon/graphite for welding backups. Expensive though. One other source I=92m going to try and follow up on tomorrow is EDM electrodes. Tool and die folks use carbon electrodes to EDM out complex shapes and they can get it in virtually any size. I have a contact at a plastic molder where they make their own molds, and he said he would give me some scrap electrode material. So I=92ll get some of that material and check it for diamagnetism. His comment was that he thought the material from some oil refinery process is pressed and =91sintered=92 to make the electrode material. So it come= s in different densities and with adders such as copper, i.e., much in the same way as brushes for motors. I=92d be interested if anyone has the numbers for diamagnetism for carbon= vs graphite, if there is a difference. I would suspect so. It would help narrow down our search for materials if we could eliminate the unsatisfactory forms right off the bat. Charles R. Patton _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Aftershock From: Oguzhan Aydogmus-HRB oaydogmus@................ Date: Wed, 29 Sep 1999 07:12:59 +0200 29.09.1999 03.10 Yalova Turkey Mag 4.8 ? Aftershock Oguzhan Aydogmus Herberts Turkiye Tel: +90 262 754 56 60 (2279 E-mail : oaydogmus@................ _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: From: Oguzhan Aydogmus-HRB oaydogmus@................ Date: Wed, 29 Sep 1999 10:30:06 +0200 Do you know about 29.09.1999 03.20 Yalova Turkey aftershock magnitude ? _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: From: =?iso-8859-9?Q?S=FCmer_Yamaner_MD?= syamaner@............... Date: Wed, 29 Sep 1999 11:45:23 +0300 According to Kandilli Observatory it was 4.8 but according to National Earthquake Information Center it was 5.0. ----- Original Message ----- From: Oguzhan Aydogmus-HRB To: 'PSN-L Mailing List' Sent: 29 =E2=E5=F0=E5=F1=ED=FF 1999 =F0. 11:30 syamaner > Do you know about 29.09.1999 03.20 Yalova Turkey aftershock magnitude ? > > > > _____________________________________________________________________ > > 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) Subject: Re: Diamagnetic materials (more) From: "Rex Klopfenstein, Jr" rklopfen@......... Date: Wed, 29 Sep 1999 11:05:24 -0400 You might check http://www.searchlightparts.com. They sell carbon arc ro= ds for the old WWII searchlights. Don't know what the pricing is like! "Charles R. Patton" wrote: > I=92ve been checking on further sources of carbon and this is what I ha= ve -- Rex Klopfentein, Jr. rklopfen@......... http://www.wcnet.org/~rklopfen _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Diamagnetic materials (more) From: Karl Cunningham karlc@....... Date: Wed, 29 Sep 1999 08:40:38 -0700 Charles, et al. Another source of carbon could be carbon piles. Some old battery testers use them and might be available from surplus outlets. Although more of a specialty item, carbon tools are used in glass blowing and vacuum tube (and CRT) manufacturing to shape the softened glass. It is preferred due to its extremely low thermal conductivity, which doesn't crack the glass. Karl _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Aftershock From: Nick & Sophie Caporossi nickcap@............. Date: Wed, 29 Sep 1999 11:46:52 -0400 Hi Oguzhan Aydogmus: Regarding the aftershock of 4.8 in Turkey, is 00:03:10utc the correct time? The USGS listed it as: 99/09/29 00:13:06 40.59N 29.31E 10.0 5.0Mb B TURKEY Nick At 07:12 AM 9/29/99 +0200, you wrote: > >29.09.1999 03.10 Yalova Turkey >Mag 4.8 ? >Aftershock > > >Oguzhan Aydogmus >Herberts Turkiye >Tel: +90 262 754 56 60 (2279 >E-mail : oaydogmus@................ _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: R: Aftershock From: "Francesco" franuc@...... Date: Wed, 29 Sep 1999 17:54:01 +0200 See our records from Italy, posted on PSN-Event List. Francesco _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Diamagnetic materials (more) From: "Larry P. Thomas wa0gwa" lpthomas@......... Date: Wed, 29 Sep 1999 11:08:27 -0500 This thread caught my interest enought to go to the local ACE hardware store and buy a couple replacement brushes for DeWalt miter ans circular saws. Each package contains two brushes approximately 1/4" x 1/2" x 3/4" and both sets I bought appear to be diamagnetic. DeWalt part number DW4001BR. I used small magnets out of the positioning system of old CDROM drives for the levitated magnet and magnets out of the positioning actuator of old hard drives. I think both are rare earth as they have an extremely strong pull. Later Larry - Imagine it / Achieve it - Dream it / Become it - Larry P. Thomas wa0gwa voice : 1 913 888-0282 Krell Technologies fax : 1 913 782-9359 8960 Bond pager : 1 913 617-HELP Overland Park, KS www.krell.com 66214-1722 USA lpthomas@......... _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Diamagnetic material (more) From: meredith lamb mlamb1@.......... Date: Wed, 29 Sep 1999 11:02:17 +0000 Hi all, Gee....this is like a old mystery....finding a source of diamagnetic material....preferably the carbon/graphite manufacturer. The more blank walls, the internet presents, the more the challenge....ha. The only admitted manufacturer I found was: http://www.asbury.com/index-markets.html They do mention the total range of products, previously speculated on. I sent a inquiry via email, specifically mentioning the the diamagnetic susceptiblity of ~ 450 in dimensionless SI units, mentioned on: http://www.physics.ucla.edu/marty/diamag/ lev4sale.html. I really doubt I'll get a reply, being I'am a private individual and not a company..... One would think Union Carbide sells something, but their site doesn't even get into carbon/graphite, from what I searched. Thanks to all, for their present and ongoing interest/efforts in this maddening mystery search for a definite source. Levitating devices maynot be worth much for seismic purposes, but its sure interesting, with the mass (magnet) response to vertical and lateral stimuli, from what I've seen visually. Meredith Lamb _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L)