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Entry  Tue Nov 14 01:31:41 2017, Craig, DailyProgress, ISS, Low Pass Dual Voltage Follower for locking the ISS ISSBox_1.jpgISSBox_2.jpgISSBox_3.jpgISSBox_4.jpg
    Reply  Wed Nov 15 16:06:29 2017, Perreca, DailyProgress, ISS, Low Pass Dual Voltage Follower for locking the ISS Untitled.jpg
Message ID: 1982     Entry time: Tue Nov 14 01:31:41 2017     Reply to this: 1985
Author: Craig 
Type: DailyProgress 
Category: ISS 
Subject: Low Pass Dual Voltage Follower for locking the ISS 

We need to lock our ISS to the PD output in real time without worrying about DC fluctuations in the PD response.

I made a dual voltage follower using an OP275 and some capacitors. 

The schematic is on the box in picture 2.

I checked both voltage follower input/output pairs with an SR785.  We see a nice low pass with cutoff frequency ~0.7 Hz.

I'll install this tomorrow.

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