From: Brett Nordgren 

To: psnlist 
Sent: Sun, 7 Oct 2012 3:37
Subject: Geophone electrical model


Hi all,

I just finished up documenting a mechanical-analog electrical model=20
for geophones.  It can be incorporated in a circuit simulation=20
program such as Spice, and allows you to look at the overall system=20
performance with respect to a ground velocity excitation. =20
It includes an Excel workbook for computing the analog equivalent=20
component values from the geophone spec. sheet, and includes some examples.
http://bnordgren.org/seismo/GeophoneModel.zip


Hi Brett,=20

    Do you have a current generator analogue for this circuit, please, or c=
an Spice=20
only use voltage generator circuits ?=20

    I am a bit puzzled by the inclusion of the SERIES coupling capacitor, C=
eqv. How=20
does this arise, please ?=20
    The Lippmann circuit gives a first order increasing output with frequen=
cy fn(f). =20

    Regards,

    Chris Chapman


      =20

=20
=20







From: Brett Nordgren <br=
ett3nt@.............>







To: psnlist <psnlist@..............>




Sent: Sun, 7 Oct 2012 3:37




Subject: Geophone electrical model





















Hi all,

I just finished up documenting a mechanical-analog electrical model=20
for geophones.  It can be incorporated in a circuit simulation=20
program such as Spice, and allows you to look at the overall system=20
performance with respect to a ground velocity excitation. =20
It includes an Excel workbook for computing the analog equivalent=20
component values from the geophone spec. sheet, and includes some examples.
http://bnordgren.org/seismo/GeophoneModel.zip


Hi Brett, 


    Do you have a current generator analogue for this circuit, please, or can Spice 

only use voltage generator circuits ? 


    I am a bit puzzled by the inclusion of the SERIES coupling capacitor, C=
eqv. How 

does this arise, please ? 

    The Lippmann circuit gives a first order increasing output with frequen=
cy fn(f).  



    Regards,



    Chris Chapman