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Entry  Wed Jul 23 23:43:28 2014, ericq, Update, LSC, Locking efforts; Wrath of the Mode Cleaner 
    Reply  Tue Jul 29 16:41:54 2014, Koji, Update, LSC, MC servo MCservo.pdf
       Reply  Wed Jul 30 00:42:27 2014, Koji, Update, LSC, MC servo MCservo.pdf
       Reply  Wed Jul 30 22:01:24 2014, Koji, Update, LSC, MC servo 
Message ID: 10293     Entry time: Wed Jul 30 00:42:27 2014     In reply to: 10285
Author: Koji 
Type: Update 
Category: LSC 
Subject: MC servo 

I used an oscillator and an oscilloscope to measure the open loop transfer function at higher frequency than 100kHz.
(I remember that I tried to use Agilent 4375A for this and failed before ... due to low input impedance???)\

Here is the update. It seems that the gain margin is not so large. We should apply low pass to prevent too large servo bump.

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