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Entry  Thu Aug 20 02:31:09 2015, ericq, Update, LSC, PRFPMI is back lock.pdf
    Reply  Tue Aug 25 04:15:51 2015, ericq, Update, LSC, PRFPMI is back 
       Reply  Tue Aug 25 16:09:54 2015, ericq, Update, IOO, IMC Tweak imcTweak.pdfCARM_TF.pdf
          Reply  Fri Aug 28 19:05:53 2015, rana, Update, IOO, IMC Tweak 
             Reply  Tue Sep 1 11:56:56 2015, ericq, Update, IOO, IMC loop shapes IMCshapes_Aug31_2015.pdfIMC_Aug31_2015.zip
                Reply  Wed Sep 2 01:31:22 2015, ericq, Update, IOO, IMC loop shapes imc_olg_trend.pdfimc_xover_trend.pdf
       Reply  Thu Aug 27 04:23:04 2015, ericq, Update, LSC, PRFPMI is back 
          Reply  Fri Aug 28 02:20:35 2015, Ignacio, Update, LSC, PRFPMI and MCL FF carmin.pngcarmout.png
Message ID: 11518     Entry time: Thu Aug 20 02:31:09 2015     Reply to this: 11528
Author: ericq 
Type: Update 
Category: LSC 
Subject: PRFPMI is back 

PRFPMI locking has been revived.

I've had 6 5min+ locks so far; arm powers usually hit ~125 for a recycling gain of about 7; visibility is about 75%

The locking script takes a little under 4 minutes to take you from POX/POY lock to PRFPMI if you don't have to stop and adjust anything.

At Koji's suggestion, I used digital REFL11 instead of CM_SLOW, which got me to a semistable lock with some RF, at which time I could check the CM_SLOW situtation. It seemed like the whitening Binary IO switch got out of sync with the digital FM status somehow... 

I've been making the neccesary changes to the carm_cm_up script. I also added a small script which uses the magnitude of the I and Q signals to set the phase tracker gain automatically based on some algebra Koji posted in an ELOG some years ago. 

The RF transition seems much smoother now, most likely due to the improved PRC and ALS stability. In fact, it is possible to hold at arm powers of >100 solely on the digital servos; I don't think we were able to do this before until the AO had kicked in. 

Right now I'm losing lock when trying to engage the CARM super boost. I also haven't switched the PRMI over to 1F signals yet. Would be good to hook the SR785 back up for a loop TF, but I'll stop here for tonight since our SURFs are presenting bright and early tomorrow morning. 

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