> From:    DMo6117771@.......
> Date:    Thu, 18 Jan 2001 22:48:13 EST
>
> i am trying to use a geospace geophone to close set of contacts that
> initiates a radio transmission to a remote reciever.  this thing needs to
be
> adjustable in sensitivity or amplification in order for human footsteps to
be
> the minimum neccessary to activate the contact closure.  it must be dc in
> order to be used in the backwoods. any help or info would be greatly
> appreciated.

So you  want to detect people, but not quakes?  Most of us
have spent a lot of time designing our semismometers to do
just the opposite!

Sounds like a project I heard about during the Viet Nam war.  It was
a remote sensor that could be dropped on the Ho Chi Min trail and
report back when people or vehicles came near.

I may have some electronics that could be modified to
solve your problem.

I am working on an inexpensive seismic circuit (amp/filter/adc) that
can run off a 9v battery. It is controlled by a PIC microprocessor
that can do other processing.  It draws less than 4.5ma, so a 9v
nicad battery would last about 100 hours.

Ciao,

Dave

>
> Thanks,
> David


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