Below are some email messages sent to the PSNLIST regarding the history of the PSN
From Steve Hammond,one of the founding members of the PSN;
..to try and answer the remainder of your questions: As for a selection of seismometers, The Lehman design was best because as it only took simple tools to build one. As you may already know the Professor that designed it and published the original Scientific America plans is also a member of this group. In the photo of your system below you provided, which I have looked at and admired many times before, it provides a good example of what you can build once you have mastered the original Lehman design. As for the amp design, as I said below, Pete Rowe provided a detailed two page design for building amps/filters and gave the design freely to the group. There has never been a lot of planning for any one aspect of the sensors people use, just a lot of experimentation. For example, I once built a Lehman for $5 from a toilet tank float filled with water and a brass rod. Ed Cranswick told me to keep the cover down on the enclosure if anybody dropped by to see my insulation… There was a member the contributed in the early days. One by the name of Sam Gazdic in Oakland, CA who provided a lot of information about sensors and systems. He worked for the State of California and became a valuable resource when you had a question about commercial seismographs. Bob Ogburn was in the National Guard and worked in electronics in the Valley. He developed an array of sensors using 4-inches of PVC pipe filled with oil for damping and ˝ of a flutter fan from the old Apple cooling systems fans. Then there were also the real old-timers Howard and Woody; the first “public citizens” to install and run seismic sensors in their homes. Howard and Woody never formally joined the PSN meetings but they did help with pen motors, chart recorders and sensors. They lived in the North Bay and in the 40’s were running seismographs and chart recorders. (I think the Sprengnether Jan Froom is letting me use actually belonged to Woody before he passed? Anyway-- ). Howard told us over lunch one day that Offenhauser at the Berkeley Seismology Lab would call them in the 40’s after WWII to see if they recorded an event and to argue over the magnitude. Woody had the best seismic shed/workroom that I have ever seen. He had his cart reorders, HAM radio equipment and workbenches all neatly laid out with seismic traces and travel time charts on the walls. It was the kind of place you could just hangout in for days at a time.
About the history; As Ed Cranswick told the story over beers several times he needed a grant to go to the AGU meeting that year and he published the “Peoples” Seismic Array paper ( which is listed in the link you provided) so he could attend the meeting and present his paper. He and Phil (a software engineer) had been working together on a number of projects and If I remember correctly it did have something to do with his work in Turkey or Russia but I’ve lost that point and can’t recall it. Anyway, Ed got his funding and went to the AGU meeting with Phil and Ed presented their work. Like I SAID, IT HAD ABSOLUTLY NOTHING TO DO WITH US. Than in Oct. 1989 the Loma P event went off in Aptos (Santa Cruz County) and it sparked a lot of interest in seismology. However, before Oct/89 inside IBM there was a group of people that had been working on their hobby, not a formal IBM product, which was seismology instrumentation. Jan From, Ted Blank, Dick and one outsider, Pete Row had already hooked-up and were sharing information. Jan was a tools programmer for IBM and wrote the software to float a 3,000 pound block of granite on streams of air so that master servo tracks could be written error free on large DASD packs and lived in Gilroy, CA. Ted Blank was IBM’s performance export for the MVS operating system and lived in New York and worked at the Poughkeepsie, NY plant.
Pete Rowe was a contractor and worked on secret electronics government projects here in San Jose, CA. Ted had written his SDAS software for data collection on a PC and had built from the 1956 plans a Lehmann seismograph. Jan had communicated via IBM’s internal discussion network and gotten the software and info from Ted and shared it with Pete as they were HAMs on the local 2m radio network and both had built and operated seismic stations. They would share info and data via the local 2m network here in San Jose run by Bruce Kenny (W6TED). I (and 250 other people) was working on developing IBM’s OSI software product at the IBM Scientific Center in Palo Alto and lived I lived in south San Jose. Jan shared his plans and Ted’s software with me and I built a Lehman and hooked it to a PC via an A/D board and amp I built from sample chips I got from local vendors. Dick Chelberg was an engineer working in the IBM plant developing DASD in San Jose and as a side profession operated a complete machine shop at his home. He had machined a Lehman and was also using Ted’s software and an IBM A/D card to collect seismic data.
One Saturday morning following we got together for coffee and donuts at my home to meet face to face and talk about seismographs and share info. As we were all using Ted’s software we needed a way to share the datasets so I volunteered to install a BBS. Within a few weeks it was operational and the IBM Think Magazine folks got wind of this seismic group operating in San Jose and asked to write an employee focus item for the Company Think Magazine and they interviewed each of us and wrote the article. The interesting thing was that totally unrelated, Ed’s AGU paper was discussed in the San Jose Mercury News. And on that Saturday morning we had kicked around a few names for the BBS and it ended up being named “THE “PUBLIC” SEISMIC NETWORK” in San Jose. So when we read about Ed Cranswick I called him at the USGS in Menlo Park and the next day he showed up at my house to see what we were doing.
From that point on our relationship grew with lots of support from the USGS and lots of great advice. John Lahr, Ed and two other’s stared to attend our meetings and as the word about the PSN got around more and more people in the Bay Area started to join the group. So did the BBS network. Jerry and Dorothy Darby were part of the 2M radio group in Pasadena and they installed a PSN BBS and were linked them together with nightly mail runs and file sharing. They also were operating seismographs at their home as were a number of folks in the LA area. Charlie Daniels In Memphis, TN had a seismograph and installed the PSN BBS in Tennessee and link it into our network. The folks at CERI also supported his site and gave him access to info on New Madrid. Allen Lynn was the Station Chief at the USGS in Menlo Park and asked me to install a PSN BBS in his office. Latterly, on top of a filing cabinet in his office, which I did. I maintained it via FTP and later John Lahr took over its operation.
So the original PSN network was a four-node BBS network and the members could post mail and event files to any of the systems and in turn a number of elementary schools and high schools started using the systems in their course work. I helped to install systems and seismographs at MT View and Los Altos high schools and Anderson Elementary in San Jose. Jan installed systems at the Gilroy Middle school and today created and maintains the seismic system and Gilroy Gardens. Pete and Ted are still active here on the list and the last time I check, Bruce and Dick lived here in CA. Ed Cranswick was in Australia and we are still arguing over who was first, the Peoples or Public Seismic Network. I’ll have to check the publication dates to see.Steve Hammond PSN, San Jose, Aptos, CA
I sent the following to the list regarding my involvement with the PSN;
When I got involved in the PSN it was already an established group. Edward Cranswick (USGS) and a few local San Jose people who worked at IBM started the PSN. Edward wrote the following back in 1996 regarding the PSN. I got involved in seismology in the early 1990s. The Loma Prieta event got my attention, so a few months or maybe a year afterwards, and since I always wanted to make a seismometer, I started to build my own. The first one was a long spring in a tube with a magnet at the end and a pickup coil on the ground. I soon discovered that I needed damping so I placed the coil and magnet in some oil. Since I had a hardware and software background I built my own ADC board and wrote my SDR program that ran under DOS. A few days after getting everything working I recorded my first local event. I think is was a M4 so it showed up very nicely on the screen. So I was hooked...
At the time I built my first system I did not know about the PSN. I happened to go to a lecture at the local USGS office where one of the seismologists told me about the group. At the time the PSN used dial-in bulletin boards to share files and communicate and I attended a few local meetings. That lasted a few years and then the Internet started to get popular in the mid 1990s, so I created the first web site and started the mailing list, and as they say, the rest is history...The earliest file I can find on my web server is Sept. of 1995, so the Redwood City PSN web site must have gone online around then. The first PSN list message is dated 31 Dec. 1995.
Larry Cochrane, Redwood City PSN
Students from South Valley Jr. High & Almaden Country School presented the poster, "Seismic Monitoring in the Classroom", "A Complement to the Traditional Middle School Science Curriculum" at the 1998 December meeting of the American Geophysical Union, in San Francisco, CA.. Students from both schools manned the booth, explaining to interested scientists what they've learned about seismology through hands on experience in their respective schools. Both schools were sponsored at the AGU meeting through the efforts of Edward Cranswick of the USGS. We appreciate the opportunity afforded to us by the AGU & USGS. We also want to thank all the visitors for their interest and the kindness they extended to our students.
Ted Blank is responsible for getting amateur seismology into the digital age with his EMON monitoring and analysis programs. Ted has worked with numerous schools, establishing seismic monitoring stations, and teaching students about the practical elements of seismology. Bob Phinney, from the Princeton Earth Physics Project (PEPP), a project of Princeton University to provide hands on seismic experience in the class room, for Jr. & High School level students. Larry Cochrane, has provided a web site, software & hardware for the Public Seismic Network (PSN), a group of amateur seismologists (and professionals) that provide seismic equipment, programs and support to interested schools.
Alan Jones, the author of several computer programs which make it possible for students to visualize, and experience from actual seismic recordings, where earthquakes occur, and how the waves travel through and around the earth. John Taber, from Wellington, New Zealand also presented a poster at the AGU meeting about his efforts to create a network of schools in New Zealand (Quake Trackers), based upon the PEPP using PSN technology.
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