>       You can make OK cheap seismic sensors using the 41 / 50 mm dia piezo 
> sounder disks and a weight, but you need a very high impedance low noise 
> amplifier, maybe 100 M Ohms input.
> 
>       Regards,
> 
>       Chris Chapman
>

If you were to suspend most of the weight of
a 4 or 5LB mass on the end of a spring and then
take up the last one ounce of weight upon such
a Piezo sounder disk would that improve
the signal receiving qualities any over
just placing a one ounce weight on it ?
A strong signal on such a device would probably ruin it.

Sincerely;
gmvoeth
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