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Entry  Fri Jan 14 01:55:26 2011, kiwamu, Update, LSC, X arm locked with C1LSC digital control 
    Reply  Fri Jan 14 11:29:00 2011, kiwamu, Update, LSC, expected open loop TF of X arm locking xarm_oltf.png
    Reply  Fri Jan 14 12:34:08 2011, Koji, Update, LSC, X arm locked with C1LSC digital control 
Message ID: 4156     Entry time: Fri Jan 14 12:34:08 2011     In reply to: 4153
Author: Koji 
Type: Update 
Category: LSC 
Subject: X arm locked with C1LSC digital control 

My feeling was that the saturation was caused by the LSC whitening filter which was always on.
Once the LSC whitening filter is controlled from C1LSC, we would be able to remove the attenuator.

Quote:

  - attenuation of RF signal

  Since the PDH signal taken by C1LSC's ADC had been saturated somewhat, we introduced a ND filter of 10 on the photo diode to attenuate the RF signal.

As a result the amplitude of the PDH signal on dataviewer became more reasonable. No more saturations.

 

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