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Wed Jan 29 14:49:48 2020, anchal, DailyProgress, BEAT, Beanote Spectrum vs FSS Gain Values
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Wed Jan 29 15:58:26 2020, anchal, DailyProgress, BEAT, Beanote Spectrum vs FSS Gain Values
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Fri Feb 7 09:57:32 2020, anchal, DailyProgress, BEAT, Spanned gain parameter space in NFSS and checked beatnote
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Fri Feb 7 18:12:03 2020, anchal, DailyProgress, BEAT, Spanned gain parameter space in SFSS and checked beatnote
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Mon Feb 10 11:07:33 2020, anchal, DailyProgress, BEAT, Spanned gain parameter space in PMCs and checked beatnote
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Thu Feb 13 15:27:18 2020, anchal, DailyProgress, BEAT, Further iterated back and forth to optimized FSS Gains.
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Message ID: 2525
Entry time: Fri Feb 7 18:12:03 2020
In reply to: 2524
Reply to this: 2526
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Author: |
anchal |
Type: |
DailyProgress |
Category: |
BEAT |
Subject: |
Spanned gain parameter space in SFSS and checked beatnote |
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I took beatnote measurements and spanned gain values (COM and FAST) on South side to see the variation in beatnote with them.
Method
- I used BNspec.py with default settings (10 kHz bandwidth at 15.625 kSa/s for 60s) while spanning the parameter space of NFSS gains.
- Every time the gain values are changed, a gainCycle.py is done and script waited for 10s before attempting beatnote measurement to let loops settle down.
- The beatnote frequency was robustly within 2 kHz of 27.34 MHz during this whole measurement.
- Overall experiment was run by spanParamSpace.py script.
Inference
- I calculated the integrated total beatnote frequency noise in the frequency range 200 Hz to 1 kHz where the total noise is expected to be dominated by coating Brownian noise.
- Unstable regions in the parameter space are clearly visible.
- But as to the stable region, once the loop gets onto that, the noise does not change much, similar to North side.
- So here as well, it seems like the beatnote noise is largely independent of the gain settings.
- I'm unsure if I should look at this and the last measured data sets differently. Maybe I'm missing something.
Data
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