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Message ID: 182     Entry time: Tue Jun 29 14:20:04 2010
Author: tarac 
Type: Notes 
Category: Laser 
Subject: Calibration [Hz/V] for modulating signal (PMC and laser) 

1) DC ext channel on PMC servo:          32.82 MHz/ V

2) Fast channel on the laser controller:   3.07 MHz/V ( Our Fn generator can provide +/- 20V -> 60 MHz span, this won't let us see all three peaks of the error signal from RefCav which has 35.5x2 = 71 MHz span)

3) Temperature actuator on the laser control:  220 MHz/V.  (1FSR= 714 MHz, 2x cavity length = 0.42m)

 

This measurement is done by scanning the laser frequency (1 and 3)or cavity length (2) and see the error signal.

The two sidebands are 43 MHz apart , divided that by the corresponding Voltage difference of the sidebands to get the calibration. For Temperature actuator we see use the PMC's FSR instead of the sidebands for better accuracy.

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