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Entry  Thu Aug 23 22:21:13 2012, rana, Configuration, IOO, MCL turned back on mcl-screen.pngmcf-noise.pdf
    Reply  Fri Aug 24 09:21:45 2012, Steve, Update, IOO, MC2 damping restored 10hrsMC2.png
       Reply  Sun Aug 26 11:53:09 2012, Jenne, Update, IOO, MC2 getting kicked up regularly 
Message ID: 7263     Entry time: Thu Aug 23 22:21:13 2012     Reply to this: 7268
Author: rana 
Type: Configuration 
Category: IOO 
Subject: MCL turned back on 

I turned on some filters and gain in the SUS-MC2_MCL filter bank tonight so as suppress the seismic noise influence on MC_F. This may help the MC stay in lock in the daytime.

Koji updated the mcdown and mcup scripts to turn the MCL path on and off and to engage the Boost filters at the right time.

The attached PNG shows the MCL screen with the filters all ON. In this state the crossover frequency is ~45 Hz. MC_F at low frequencies is reduced by more than 10x.

I also think that this may help the X-Arm lock. The number of fringes per second should be 2-3x less.

Attachment 1: mcl-screen.png  326 kB  | Hide | Hide all
Attachment 2: mcf-noise.pdf  56 kB  Uploaded Thu Aug 23 23:28:55 2012  | Hide | Hide all
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