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 ChapmanSubject: 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.BChris Chapman