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Entry  Wed Jan 29 14:49:48 2020, anchal, DailyProgress, BEAT, Beanote Spectrum vs FSS Gain Values Beatnote_vs_FSSGain.pdf
    Reply  Wed Jan 29 15:58:26 2020, anchal, DailyProgress, BEAT, Beanote Spectrum vs FSS Gain Values Beatnote_vs_FSSGain.pdf
       Reply  Fri Feb 7 09:57:32 2020, anchal, DailyProgress, BEAT, Spanned gain parameter space in NFSS and checked beatnote NFSS_Spanned_Beatnote_Variation.pdf
          Reply  Fri Feb 7 18:12:03 2020, anchal, DailyProgress, BEAT, Spanned gain parameter space in SFSS and checked beatnote SFSS_Spanned_Beatnote_Variation.pdf
             Reply  Mon Feb 10 11:07:33 2020, anchal, DailyProgress, BEAT, Spanned gain parameter space in PMCs and checked beatnote PMC_Spanned_Beatnote_Variation.pdf
                Reply  Thu Feb 13 15:27:18 2020, anchal, DailyProgress, BEAT, Further iterated back and forth to optimized FSS Gains. FSS_Gain_Span.pdf
Message ID: 2531     Entry time: Thu Feb 13 15:27:18 2020     In reply to: 2526
Author: anchal 
Type: DailyProgress 
Category: BEAT 
Subject: Further iterated back and forth to optimized FSS Gains. 

I took beatnote measurements and spanned gain values in the PMC to see if stability issues in PMC loops can be affecting the FSS downstream.


Method

  • I used BNspec.py with default settings (10 kHz bandwidth at 15.625 kSa/s for 60s) while spanning the parameter space of PMC gains.
  • The beatnote frequency was robustly within 2 kHz of 27.34 MHz during this whole measurement.
  • The overall experiment was run by spanParamSpace.py script.
  • First I spanned North gains using the last optimum values found for South Side and tried to span the area towards which we found minima earlier.
  • Next, I used the new minima found for North side and spanned region in South side.
  • This time, I used sum of the ASD of beatnote frequency between 300 to 600 Hz to determine improvement in noise overall.
  • Still, I would say, the improvement is hardly more than 5% over large areas of parameter space, meaning mostly BN noise is independent of these gains.

Final result

  North South
COM Gain (dB) 12 22
FAST Gain (dB) 10 17

Data

 

Attachment 1: FSS_Gain_Span.pdf  30 kB  | Hide | Hide all
FSS_Gain_Span.pdf FSS_Gain_Span.pdf
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