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Entry  Thu Jun 14 21:37:37 2012, yuta, Update, Green Locking, succeeded in 1FSR mode scan YarmScan20120614.png
    Reply  Fri Jun 15 00:50:54 2012, yuta, Update, Green Locking, scanned Y arm for 5FSR YarmScan20120614_2.png
       Reply  Fri Jun 15 01:53:05 2012, Koji, Update, Green Locking, scanned Y arm for 5FSR 
          Reply  Sat Jun 16 12:03:41 2012, Zach, Update, Green Locking, scanned Y arm for 5FSR 
             Reply  Sat Jun 16 13:01:17 2012, yuta, Update, Green Locking, scanned Y arm for 5FSR YarmScanDV.png
       Reply  Sat Jun 16 18:17:00 2012, yuta, Update, Green Locking, Y arm length using 5FSR scan ALS-BEATY_COARSE_I_IN1_DQ.pngCalibYarmScan20120614_2.png
          Reply  Sat Jun 16 18:51:44 2012, Koji, Update, Green Locking, Y arm length using 5FSR scan 
             Reply  Sat Jun 16 19:32:11 2012, yuta, Update, Green Locking, Y arm length using 5FSR scan 
Message ID: 6823     Entry time: Sat Jun 16 12:03:41 2012     In reply to: 6820     Reply to this: 6824
Author: Zach 
Type: Update 
Category: Green Locking 
Subject: scanned Y arm for 5FSR 

Is that time stamp really correct? I wanted to look at the signal closely to see if I could get any feeling for why it would look so different when positive vs. negative, but I do not see a triangle anywhere near this time (1023780144)...

Quote:

Interesting. It seems for me that there is a dependence of the noisiness as the beat frequency is scanned.

As you increase (or decrease?) the offset, C1:ALS-BEATY-COARSE_I_IN1 becomes bigger and more crisp.
The resulting out-of-loop stability also seems to be improved as you can see from the crispness of the PDH signal.

Do you find why this happens? Is this because the beat S/N depends on the beat frequency due to the PD noise?

 

 

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