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Entry  Mon Nov 3 15:16:28 2014, Dmass, Noise Hunting, Noise Budget, New beat spectrum: ErrSigs.pngBeatNz.png
    Reply  Mon Nov 3 16:15:21 2014, Dmass, Noise Hunting, Noise Budget, Beat spectrum not ltd by  
       Reply  Mon Nov 3 20:27:28 2014, Dmass, Noise Hunting, Noise Budget, ISS servo fail? 
          Reply  Wed Nov 19 14:54:36 2014, nicolas, Noise Hunting, Noise Budget, ISS servo fail?  
       Reply  Tue Dec 2 22:51:52 2014, Dmass, Noise Hunting, Noise Budget, Beat spectrum not ltd by  PDH_demod_chain.png
          Reply  Sat Sep 12 14:25:05 2015, Dmass, Noise Hunting, Noise Budget, Beat spectrum not ltd by  
    Reply  Mon Nov 3 20:36:14 2014, Dmass, Noise Hunting, Noise Budget, New beat spectrum: 
       Reply  Tue Nov 25 22:45:43 2014, Dmass, Noise Hunting, Noise Budget, New beat spectrum: 
          Reply  Wed Dec 3 17:02:31 2014, Dmass, Noise Hunting, Noise Budget, Noise budget cleaning up 
             Reply  Thu Dec 4 02:45:49 2014, Dmass, Noise Hunting, Noise Budget, Noise budget cleaning up PDH_sensing_nz.pngLB1005inputNoise.png
                Reply  Sun Dec 7 12:42:55 2014, rana, Noise Hunting, Noise Budget, Scatter Noise hump is RAM 
Message ID: 1163     Entry time: Mon Nov 3 16:15:21 2014     In reply to: 1162     Reply to this: 1164   1172
Author: Dmass 
Type: Noise Hunting 
Category: Noise Budget 
Subject: Beat spectrum not ltd by  

I looked at the sensing noise (which goes WAY up when the ground of the IF port of the mixer touches the ground of the servo box - from 13 nV to 100 nV)

Sensing noise, input referred servo box noise, and in loop err signal noise are ALL below the current beat limit ( ~ 7e-2 Hz/rtHz around 1kHz ) by ~5x

 

We should figure out what this noise floor is.

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