In a message dated 1/9/00 6:46:37 PM Pacific Standard Time, ChrisAtUpw@....... writes: > > Have you tried testing a geophone by sitting it on a flat plate on small > > li-lo cushion filled with water? Then use a syringe to inject a ml of water. > An impulse could be given to a horizontal seismometer by discharging a > capacitor through a nearby coil of wire. The induced currents give a > repulsive force. Hello All, Any pulse you record by droping water or beads records too much of the enviroment around the geophone. If you take a step function response like I recorded it, and get the second derivative of this signal, you will have an impulse response of the geophone with little effects of the surrounding area. Use a pulse generator to get the imulse response of the rest of your electronic system. With thee two signals, you can derive an entire system response and remove any undesired system response from your seismic data. Exploration seismoligists like to work with data that has not been phase distorted by geophones and/or amplifiers, etc. I have also used this same method to record the step function of horizontal geophones. George Erich on the + side http://hometown.aol.com/gee777/myhomepage/profile.html _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L)
Larry Cochrane <cochrane@..............>