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Message ID: 5530     Entry time: Fri Sep 23 16:56:07 2011
Author: Mirko 
Type: Update 
Category: LSC 
Subject: Desired MC modulation frequency measurement, tuning of modulation frequency 

[ Mirko, Koji, Suresh ]

Looked into the modulation frequency that should pass the input MC. With a locked MC looked at the RF output of the PD in refl of the MC. Looked at the beat between 11MHz and 29.5MHz. Minimizing it by fine-tuning the 11MHz freq. ( which means maximizing the 11MHz transmission).

SB freq. [MHz]     Beat power [dBm]

11.065650          -75

11.065770          -80 (diving into spec. analyzer instrument noise)

11.066060          -80 (surfacing out of spec. analyzer instrument noise)

Set the freq. to the middle of the last two points: 11.065910MHz at 16:26.

ToDo: How big a problem is the AM?

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