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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: 10300     Entry time: Wed Jul 30 22:01:24 2014     In reply to: 10285
Author: Koji 
Type: Update 
Category: LSC 
Subject: MC servo 

In fact there is a pomona box between the HV amp and the laser.
It is expected that the combination of the box and the laser PZT (2.36nF by Elog #3640) provides poles at 2.9Hz and 148kHz and a zero at 32Hz.
Basically, the gain of this stage is 0.1 at 10kHz. So the injected noise is reduced by factor of 10. It is just barely OK.
I need a bit more careful design of the output stage for the MC servo.

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