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Message ID: 1580     Entry time: Sun Sep 13 11:31:04 2015
Author: Antonio 
Type: DailyProgress 
Category: BEAT 
Subject: PLL noise comparison at different PDH gain settings 

Summary

========

Measurement of the PLL noise have been taken at different PDH gains settings. Noise start to increase when the gain on the oh North loop

are below North: Common/Fast=500/300 and South: Common/Fast=420/420. Stays fairly the same with higher values.

 

The measurement are still in V/sqrt(Hz), but for now I use them only for comparison purpose.

 

Figure:

Noise comparison at different gains: In the legend are the "values" of the gains (the numbers on the knobs)

Current measurements in Vrms/sqrt(Hz)

Beat freq = ~ 65 MHz;

FM deviation = 400kHz

gain = 20;

 

Data

Data are on the lab control/home/data/20150912_PLL_noise/

 

Attachment 1: NoiseComparison_20150912_Vrms.pdf  40 kB  | Hide | Hide all
NoiseComparison_20150912_Vrms.pdf
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