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Message ID: 1796     Entry time: Mon Jul 27 14:12:14 2009
Author: rana 
Type: Summary 
Category: SUS 
Subject: TM Coil Noise Spectra 
Rob noticed that the ITMY DAC channels were saturating occassionally. Looking at the spectrum we can see why.
With an RMS of 10000 cts, the peak excursions sometimes cause saturations.

There's a lot of mechanical noise which is showing up on the ITM oplevs and then going to the mirror via
the oplev servo. We need to reduce the mechanical noise and/or modify the filters to compensate. The ITM
COIL_OUT RMS needs to be less than ~3000.
Attachment 1: Coils.pdf  210 kB  Uploaded Mon Jul 27 15:13:10 2009  | Hide | Hide all
Coils.pdf
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