Dear Everyone, I still have a lot to learn so please forgive my ignorance. I know that teleseismic events generally dominate in the lower frequency range. Therefore a Lehman seismometer with its longer natural period seems like it would be the instrument of choice for detecting teleseismic events. However, everything I read tells me the displacement sensor, which is found on the bob of the Shackleford-Gundersen Seismometer can be built to detect much weaker events than the velocity sensor found on the end of a Lehman. It seems like the thing to do then is build Lehman with a displacement sensor similar to the one found on a Shackleford-Gundersen seismometer in place of the magnet and coil on the boom of the Lehman. I have not heard of anyone doing this. Is there a reason? Something I have not taken into consideration? I'm just curious because I'm looking to build my second instrument. My first is a Shackleford-Gundersen which I have been running since the end of December. I've picked up lots of quakes with it since then. The only big one I missed was the great quake in India due to my data logging computer re-booting after a minor power blip. (Just my luck!!!) Now the computer is on a UPS, go figure. Thanks for any info anyone may have. Mark Andrews Texas A&M Class of '02 (Gig 'em) __________________________________________________________ Public Seismic Network Mailing List (PSN-L)
Larry Cochrane <cochrane@..............>