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Entry  Sat Nov 19 06:04:43 2011, Suresh, Update, IOO, MC_WFS Servo: The MC2_TRANS_PIT and YAW loops switched ON WFS_OUTMx_Lastgood.pngWFS_OUTMATRIX_20111118.pngWFS_err_MC2T_on_OMx5_20111118.png
    Reply  Sat Nov 19 10:41:30 2011, rana, Update, IOO, MC_WFS Servo: The MC2_TRANS_PIT and YAW loops switched ON 
Message ID: 5959     Entry time: Sat Nov 19 10:41:30 2011     In reply to: 5958
Author: rana 
Type: Update 
Category: IOO 
Subject: MC_WFS Servo: The MC2_TRANS_PIT and YAW loops switched ON 

I'm quite sure that this is not good: since MC2 can produce a signal in WFS1 and WFS2, it cannot be removed in this way from the actuation without introducing a significant cross-coupling between the MC_TRANS and WFS loops.

Really need loop TFs measured and compared with the model.

The WFS noise model will also show that we need to have a much lower UGF in the MCT loop since that sensor is just a DC QPD: it can never have as good of a sensing noise as a good WFS. In the current case with no Whitening, this is even more so.

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