In a message dated 01/11/2007, gmvoeth@........... writes:

I have  the best way to simulate this with smaller geophones is to pulse it 
with a  battery limiting
the current flow ( resistor ) to whatever produces 100 or  so microvolts 
across the geophone.



Hi Geoff,
 
    One other way to do it is to use a capacitor with a  resistor in series. 
You charge up the capacitor to a known voltage and simply  short it across the 
geophone, seismometer etc. This supplies a known charge I x  T to the system 
and the resistor damps any oscillations. 
 
    Regards,
 
    Chris Chapman



   






In a message dated 01/11/2007, gmvoeth@........... writes:
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  the best way to simulate this with smaller geophones is to pulse it with a=
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  battery limiting
the current flow ( resistor ) to whatever produces 100=
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  so microvolts across the geophone.


Hi Geoff,
 
    One other way to do it is to use a capacitor wi=
th a=20
resistor in series. You charge up the capacitor to a known voltage and simpl=
y=20
short it across the geophone, seismometer etc. This supplies a known charge=20=
I x=20
T to the system and the resistor damps any oscillations. 
 
    Regards,
 
    Chris Chapman