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Entry  Fri Sep 18 13:33:17 2015, ericq, Update, LSC, Fast ALS troubles - Noise at 36kHz IRlock_noises.pdf
    Reply  Fri Sep 18 16:08:41 2015, ericq, Update, LSC, Fast ALS troubles - Noise at 36kHz PRMIlock_REFLspectra.pdfIMCspectrum.pdf
       Reply  Fri Sep 18 19:15:35 2015, rana, Update, LSC, Fast ALS troubles - Noise at 36kHz 
    Reply  Tue Sep 29 16:52:49 2015, ericq, Update, LSC, Fast ALS troubles - unknown zero OLG_fastALS.pdf
       Reply  Tue Sep 29 18:03:11 2015, rana, Update, LSC, use LISO Screen_Shot_2015-09-29_at_5.55.34_PM.png
          Reply  Wed Sep 30 10:00:02 2015, ericq, Update, LSC, used LISO 
       Reply  Fri Oct 2 03:29:16 2015, ericq, Update, LSC, Fast ALS progress - AO path crossed over, but no high BW crossedover.pdf
          Reply  Fri Oct 9 13:31:21 2015, ericq, Update, LSC, ALS plant shape xarm_plantTFs.pdf
             Reply  Fri Oct 9 14:50:18 2015, Koji, Update, LSC, ALS plant shape 
                Reply  Fri Oct 9 16:23:25 2015, ericq, Update, LSC, ALS plant shape 
                   Reply  Tue Oct 13 16:28:21 2015, ericq, Update, LSC, Fast ALS pomona liso_lp.zip2LPfit.pdf
Message ID: 11649     Entry time: Tue Sep 29 18:03:11 2015     In reply to: 11648     Reply to this: 11651  
Author: rana 
Type: Update 
Category: LSC 
Subject: use LISO 

Use LISO - see what it tells you. I would think that you should make a differential RC filter to get the right behavior. (e.g. 1K on each leg and 1 uF between them)

Each leg of the diff input of the board has a 4k input impedance.

But surely the AO input to the MC servo should also make sense independently.

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