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Entry  Fri Sep 4 00:58:29 2015, rana, Update, CDS, soldering the Generic Pentek interface board 
    Reply  Fri Sep 4 08:00:49 2015, Ignacio, Update, CDS, RC low pass circuit (1s stage) of Pentek board circuit.pdfcircuit.png
       Reply  Fri Sep 4 09:23:32 2015, Ignacio, Update, CDS, Modified Pentek schematic schematic.pdf
Message ID: 11573     Entry time: Fri Sep 4 08:00:49 2015     In reply to: 11570     Reply to this: 11574
Author: Ignacio 
Type: Update 
Category: CDS 
Subject: RC low pass circuit (1s stage) of Pentek board 

Here is the transfer function and cutoff frequency (pole) of the first stage low pass circuit of the Pentek whitening board.

Circuit:

R1 = R2 = 49.9 Ohm, R3 = 50 kOhm, C = 0.01uF. Given a differential voltage of 30 volts, the voltage across the 50k resistor should be 29.93 volts.

Transfer Function: 

Given by, 

H(s) = \frac{1.002\text{e}06}{s+1.002\text{e}06}

So low pass RC filter with one pole at 1 MHz.

I have updated the schematic, up to the changes mentioned by Rana plus some notes, see the DCC link here: [PLACEHOLDER]

I should have done this by hand...crying

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circuit.pdf
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