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Message ID: 4612     Entry time: Tue May 3 14:35:44 2011
Author: Larisa Thorne 
Type: Configuration 
Category: Electronics 
Subject: Jenne-Seismometer LPF project 

 I was charge with making a Non-Inverting Op Amp Low Pass Feedback circuit for Jenne, which may somehow be integrated into a seismometer project she's working on.

 

Circuit diagram is attached. Calculations show that R1, R2 and C have the following relationship: if R1=10^n, R2=10^(n+1), C=10^(-n-4). For the particular circuit being modeled by the transfer function, R1=100 Ohm, R2=1k Ohm, and C=1uF.

Attached also is the circuit's Bode plot, showing frequency versus gain and phase, respectively. The frequency versus gain graph is true to what the circuit was calculated to generate: a gain of +20 and a cutoff frequency at 200Hz. Not sure what's going on with the frequency verus phase plot.

Attachment 1: SeisLPFdiagram.jpg  34 kB  | Hide | Hide all
SeisLPFdiagram.jpg
Attachment 2: seisLPF.Bose.jpg  28 kB  | Hide | Hide all
seisLPF.Bose.jpg
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