Hi Jim I seen your post was 1/9/2000 and appeared ready to start getting some reads. My last "clean" read of an event was 1/8/2000 (M 7.1 from Tonga Islands) I see a lot of events superimposed in the noise but not worth sending to the group. In the midwest, I think, readable events are a bit slower than for those that are out in the Pacific or California. But I am wondering?, you may have been able to see the Maine 3.4? I came in this morning to find the boom of the Lehman over to it's stop. Flat line on the screen. I have the period set to 16/17 seconds and I am considering dropping it back. This has happened several times now. The concrete, I guess that it is setting on shift's. Or, things change somewhere just a micron here or there. I didn't have to adjust it even at 14 second period. Sensitivity compared to when I started and I had it set to it's easy to attain 12 second period?... I don't think I've noticed a difference other than the noise floor is much higher now and I have to adjust it periodically. I'd think that location is everything. There isn't an abonded gold mine on my city lot! Darn! I guess the point is, if the thing has set over night flat lined, what good did the longer period do. With local noise, most of the weaker reads I get have to happen during the quiet time of night. I was hoping to see if I could of detected the Maine 3.4 superimposed in the noise but...., _______________________________________________ ! At 11:31 PM 1/9/00 -0500, you wrote: >Thanks to Jim and Kevin, I now have a Lehman boom that is beginning to >behave correctly. Thank you both for you help. > >In measuring the 'period' of the boom, is this the measurement of time it >takes the boom to swing "out and back", when pushed, or the time it takes >for the oscillations to die out completely? If I manually deflect the boom >~1" off of center, is the period the time it takes the boom to come back to >center, or the time it takes the boom to move out to one side and then >back past center to the other side? > >I know these are VERY elementary questions for this list, but hey, I've got >to start somewhere, don't I ? > >My thanks in advance to anyone who wishes to help me out. > >Jim Martin >New Haven, Indiana > > >_____________________________________________________________________ > >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)
Larry Cochrane <cochrane@..............>