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Entry  Thu Aug 28 13:40:05 2014, Evan, DailyProgress, FSS, PDH error signal on north cavity npdh_broad.pdfnpdh_fine.pdfnpdh_sweep.zip
    Reply  Thu Aug 28 20:47:24 2014, Evan, DailyProgress, FSS, PDH error signal on north cavity npdh_sim.pdfnpdh_sim_narrow.pdffpbirefringence.pdf
       Reply  Fri Aug 29 09:21:26 2014, Evan, DailyProgress, FSS, PDH shot noise estimate noiseBudget.pdf
Message ID: 1490     Entry time: Thu Aug 28 20:47:24 2014     In reply to: 1487     Reply to this: 1491
Author: Evan 
Type: DailyProgress 
Category: FSS 
Subject: PDH error signal on north cavity 


North PZT sweep: 10 Vpp triangle wave, 3 Hz

North slow control voltage: 3.6805 V

Actuation on north broadband EOM removed

Phase tuning needed, mode-matching needed

Find TNC-SMA converters

 Here's what I expect to happen given

  • perfect mode-matching,
  • critical coupling with 150 ppm transmissivity for each mirror,
  • p/s mode splitting of 2.0 MHz, and
  • perfect demod phase.

It seems to match up qualitatively with the measurement. In particular, it does not appear possible to exceed 70% visibility for each mode.

Attachment 1: npdh_sim.pdf  84 kB  Uploaded Thu Aug 28 21:50:49 2014  | Hide | Hide all
Attachment 2: npdh_sim_narrow.pdf  83 kB  Uploaded Thu Aug 28 21:50:59 2014  | Hide | Hide all
Attachment 3: fpbirefringence.pdf  252 kB  Uploaded Thu Aug 28 22:09:43 2014  | Hide | Hide all
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