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Entry  Mon Dec 19 22:05:09 2016, Koji, Summary, IOO, PMC, IMC aligned. The ringdown PD/Lens removed. 
    Reply  Wed Dec 21 21:03:06 2016, Koji, Summary, IOO, IMC WFS tuning DSC_0142.JPG
       Reply  Thu Dec 22 18:39:09 2016, Koji, Summary, IOO, IMC WFS tuning WFS_error_noise.pdfWFS_error_noise_chans.pdf
          Reply  Fri Dec 23 20:53:44 2016, Koji, Summary, IOO, IMC WFS tuning DSC_0144.JPGDSC_0145.JPG
             Reply  Fri Dec 23 21:05:56 2016, Koji, Summary, IOO, IMC WFS tuning IMC_WFS_segment_TF.pdfIMC_WFS_channels_TF.pdfIMC_WFS_161221_table1.pdfIMC_WFS_161221_table2.pdfIMC_WFS_161221.xlsx.zip
                Reply  Sun Dec 25 14:39:59 2016, Koji, Summary, IOO, IMC WFS tuning 
                   Reply  Mon Dec 26 12:45:31 2016, Koji, Summary, IOO, IMC WFS tuning IMC_REFL_TRANS_26hrs.pngIMC_TRANS_P_Y_26hrs.png
          Reply  Thu Dec 29 13:22:21 2016, rana, Summary, IOO, IMC WFS tuning 
             Reply  Thu Dec 29 16:52:51 2016, Koji, Summary, IOO, IMC WFS tuning 
                Reply  Thu Dec 29 21:35:30 2016, rana, Summary, IOO, IMC WFS tuning Screen_Shot_2017-01-03_at_5.55.13_PM.png
                   Reply  Tue Jan 24 01:04:16 2017, gautam, Summary, IOO, IMC WFS RF power levels MC1_misalignment.png
                      Reply  Fri Jan 27 00:14:02 2017, gautam, Summary, IOO, IMC WFS RF power levels 
Message ID: 12689     Entry time: Thu Dec 29 16:52:51 2016     In reply to: 12688     Reply to this: 12690
Author: Koji 
Type: Summary 
Category: IOO 
Subject: IMC WFS tuning 

Koji responding to Rana

> For the rough calibration below 10 Hz, we can use the SUS OSEM cal: the SUSPIT and SUSYAW error signals are in units of micro-radians.

I can believe the calibration for the individual OSEMs. But the input matrix looked pretty random, and I was not sure how it was normalized.
If we accept errors by a factor of 2~3, I can just naively believe the calibration factors.

> If the RF signals at the demod input are low enough, we can consider either increasing the light power on the WFS or increasing the IMC mod. depth.

The demod chip has the conversion factor of about the unity. We increased the gains of the AF stages in the demod and whitening boards. However, we only have the RMS of 1~20 counts. This means that we have really small RF signals. We should check what's happening at the RF outputs of the WFS units. Do we have any attenuators in the RF chain? Can we skip them without making the WFS units unstable?

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