ALL LIST MEMBERS
If memory serves, I believe Jeff Batten once wrote that you could make a 
short period seismograph (6 sec.) detect teleseismic events by using a long 
period filter (20 seconds.  I believe he also wrote that you could make it 
detect both teleseismic and local events by connecting the output 
simutaneously to a long period filter and a short period filter and summing 
the outputs of both using a summing amplifier.
Does anyone know whether I got this right and has anyone tried it.  Is Jeff 
still around - I have not seen a posting from him in a very long time?   Is 
this a better (easier to make for someone not versed in electronics) approach 
than using an equalising circuit such as described by Roberts in BSSA?

BTW, my seismograph is a velocity model of the STM-8 at a period of about 5.5 
seconds.
Jim Allen
Cerritos, Calif. 

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