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Message ID: 6680     Entry time: Fri May 25 02:56:44 2012
Author: Den 
Type: Update 
Category: SUS 
Subject: MC3 local damping 

I've terminated input to AA filters and measured signal to coils C1:SUS-MC3_??COIL_OUT.

DSC_4305.JPG

 

I compared this noise to the signal when OSEM are connected to ADC.

    osem_noise.png

 

I made BNC -> LEMO board such that all LEMOs have the same signal equal to BNC signal. I provided excitation of 50 mV as white noise to the input of the AA filter and measured coherence between excitation and MC3 coil driver. The path is

AA -> ICS 110 -> Pentium -> Pentek -> AI -> Univ Dewhitening -> Coil Driver

As all inputs have the same signal, matrices that recombine the signals should not affect coherence. But what I got for coherence between AA IN / Dewhitening OUT is

osem_coil.png

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