Subject: Station GVA current Schematic for low resistance Geophone SPZ (HS=
10)


t completed a crude N=3D8 Gain x1 LPF with a knee at 10Hz (about)=20
and my first try went well. I think this is BUTTERWORTH.=20
=20
http://gmvoeth.home.mchsi.com/LATEST/CIRCUIT/GVA_CIRCUIT.HTML=20
=20
Hi Geoff,


    Your circuit is faulty. You need an additional 2 muF capacitor across=
 R1.B

Chris Chapman






Subject: Station GVA current Schematic for low resistance Geophone SPZ (H=
S10)





t completed a crud=
e N=3D8 Gain x1 LPF with a knee at 10Hz (about) 

and my first try went well. I think this is BUTTERWORTH. 

 

http://gmvoeth.home.mchsi.com/LATEST/CIRCUIT/GVA_CIRCUIT.=
HTML 

 


Hi=
 Geoff,



 


    Your circuit is faulty. You need=
 an additional 2 muF capacitor across R1.B


 


Chris Chapman