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Entry  Thu Sep 5 19:32:02 2019, anchal, DailyProgress, PMC, North PMC might be cause of 500Hz bump BN_NPMCErr_CrossSpec.pdf
    Reply  Mon Sep 9 16:31:34 2019, anchal, DailyProgress, PMC, North PMC open loop investigation NPMC_openInvestifation.pdf
       Reply  Tue Sep 10 17:13:51 2019, anchal, DailyProgress, PMC, North PMC Servo Card Upgraded 
Message ID: 2420     Entry time: Mon Sep 9 16:31:34 2019     In reply to: 2417     Reply to this: 2421
Author: anchal 
Type: DailyProgress 
Category: PMC 
Subject: North PMC open loop investigation 

I opened the NPMC servo box and ran TF analysis up to all test points and compared with their zero model. Everything looks normal in these transfer functions.
So the oscillations might be happening due to closing of the loop. I'll take a measurement of total open-loop transfer function next with the PDs and PZT in the loop.

Updated schematics and Zero Model

Code and Data

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