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ID Dateup Author Type Category Subject Text Attachments
  2468   Wed Oct 30 15:15:28 2019 anchalNotesPMCReplacing U5A AD602 didn't solve the issue.I brought a new AD602AR from 40m and replaced
the U5A
AD602 which from the previous
  
  2469   Wed Oct 30 18:35:31 2019 anchalNotesPMCIssue closedIt turns out I did not have a full understanding
of the problem and it was not really a problem.
The blanking (pin 4) on U5A AD602 doesn't
  
  2470   Fri Nov 1 17:54:47 2019 anchalDailyProgressFSSFSS Diagnostics - RFPD RF Ouput under inspectionFirst step in FSS Diagnostics was to see
RF output from the RFPDs in FSS when they
are locked. I ran some extensive measurements
 NFSS_RFPD_Output_Oscilloscope.pdfSFSS_RFPD_Output_Oscilloscope.pdfNFSS_RFPD_RF_OUT_COUPLED.pdfSFSS_RFPD_RF_OUT_COUPLED.pdf 
  2471   Mon Nov 4 12:15:01 2019 anchalNotesPMCChanging the autolocking methodTrying gain sliding like 40m

Rana
told me that in 40m, the PMCs are autolocked
by reducing the gain of the loop and changing
  
  2472   Mon Nov 4 15:03:26 2019 anchalDailyProgressFSSRaised North TTFSS; Fixed the boxes.I raised the North TTFSS box by 6 inches
to make way for working on South box and
to reduce the congestion of connectors in
 signal-attachment-2019-11-04-161746.jpeg 
  2473   Mon Nov 4 20:13:44 2019 anchalNotesBEATQuick note: FSS Loop Gain ChangesSouth Common Gain: 24 dB! , Fast Gain:
14 dB

North Common Gain: 10 dB, Fast
  
  2474   Tue Nov 5 18:37:59 2019 anchalDailyProgressFSSFSS Diagnostics - TTFSS Testpoint Spectrum DataMeasurement method


All
measurements were taken withAG4395A for high
frequency and SR785 for low frequency and
 FSS_TP_Spectrum.pdf 
  2475   Sat Nov 9 13:46:08 2019 shrutiMiscElectronics EquipmentBorrowedI've borrowed a Marconi VCO, a
mini-circuits LPF and mixer from the
CTN lab for use at the WB EEshop.
  
  2476   Sat Nov 9 19:28:36 2019 anchalDailyProgressFSSFSS Diagnostics - Loop nonlinearity TestMethod

I've
wrote this script, nonlinTF.py
which controls a Marconi 2023A and SR785
 NFSS_NonLinearity_Test.pngSFSS_NonLinearity_Test.pngsignal-attachment-2019-11-09-195635.jpeg 
  2477   Mon Nov 11 20:42:49 2019 anchalDailyProgressFSSFSS Diagnostics - Two Tone TestMethod


RFPD of the FSS loops were
tested through there Test input ports (Updated
 NFSS_RFPD_SN009_TF_11-11-2019_183131.pdfSFSS_RFPD_SN010_TF_11-11-2019_203310.pdfFSStwoToneTest.pdf 
  2478   Tue Nov 12 11:39:48 2019 anchalDailyProgressFSSFSS Diagnostics - RFPD RF Ouput under inspectionI calculated these values by integrating
in the 8 MHz neighborhood around the marked
harmonic peak, the power spectral density
  
  2479   Tue Nov 12 18:36:59 2019 anchalDailyProgressFSSFSS Diagnostics - Two Tone Third Order Intermodulation TestIn line with industrial practices, I did
two tone third order intermodulation test
today on the FSS RFPDs. This test was inspired
 FSStwoToneThirdOrderIM.pdf 
  2480   Thu Nov 14 12:19:32 2019 ranaDailyProgressFSSFSS Diagnostics - Two Tone Third Order Intermodulation Testcool - how bout use this new no-how to
estimate the excess in FSS?
  
  2481   Tue Nov 19 18:51:02 2019 anchalDailyProgressFSSFSS Diagnostics - Second-order Distortion CalculationI did some theoretical calculations using
the datasheet value of second harmonic SFDR
 FSSDistortionCalc.pdfFSSDistortion.zip 
  2482   Wed Nov 27 13:59:24 2019 anchalDailyProgressFSSFSS Diagnostics - TTFSS TP1 TimeSeriesI took time-series data at TP1
on NFSS. This is just after
the elliptical filter which is after the
 NFSS_TP1_Oscilloscope.pdf 
  2483   Wed Nov 27 15:17:51 2019 anchalDailyProgressFSSFSS Diagnostics - Quick HF OLTF of NFSSI quickly took a high-frequency Open Loop
Gain measurement of NFSS loop at 10 dB COM
Gain and 10 dB FAST gain, using the same
 NFSS_OLTF_HF.pdf 
  2484   Wed Nov 27 16:31:20 2019 ranaDailyProgressFSSFSS Diagnostics - Quick HF OLTF of NFSSI doubt it.

When feedback loops be noisy and
busted,
  
  2485   Tue Dec 3 17:27:54 2019 Ian MacMillanNotesFSSFSS Plant Model v2The new circuit design has been built and
is shown below. I tested the transfer functions
and the PZT path looks good by eye but the
 IMG_8065.jpegIMG_8069.jpeg 
  2486   Wed Dec 4 17:09:44 2019 anchalDailyProgressTempCtrlIncreased range of out-of-loop temperature sensorThis has happened few times now that acromag
channel for the can heater driver stopped
updating according to the PID script and
  
  2487   Wed Dec 4 18:11:09 2019 anchalDailyProgressFSSFree running laser frequency noise spectrumI took a spectrum of PMC error signal when
the FSS loop is not closed. This should provide
a rough estimate of the free running laser
 PMCErrorSignals.pdf 
  2488   Thu Dec 5 18:25:11 2019 ranaDailyProgressFSSFree running laser frequency noise spectrumwhen the
NPRO crystal is oscillatin

 
  
  2489   Mon Dec 9 18:08:13 2019 Ian MacMillanNotesFSSFSS Plant Model v2I tested the circuit and got the attached
results. The PZT transfer function looks
reasonable. some adjustments to the values
 OutputGraphsTransferFunction.pdf_Circuit_Design_V1.zip 
  2490   Mon Dec 9 19:54:44 2019 anchalDailyProgressFSSFSS Diagnostics - How much distortion affects the functioning of PDH?I'm trying to think hard with my small
brain how the distortion would affect the
PDH functioning and inject noise in the frequency
  
  2491   Tue Dec 10 11:57:58 2019 Ian MacMillanNotesFSSFSS Plant Model v2 

First, off I forgot a resistor
on the previous diagram so here is the fixed
 IMG_8124.jpeg 
  2492   Tue Dec 10 17:03:41 2019 anchalDailyProgressLaserLaser Settings back to defaultsI put laser settings on both North and
South Cavities back to default. From this
point onwards, all settings about the lasers
  
  2493   Thu Dec 12 11:54:11 2019 Ian MacMillanNotesFSSFSS Plant Model v2Testing the circuit using SRmeasure
and AGmeasure, I got more accurate readings
of the transfer functions. The PZT path TF
 PZT_LowFq_V1.pdfPZT_HighFq_V1.pdfEOM_LowFq_V1.pdfEOM_HighFq_V1.pdf 
  2494   Thu Dec 12 19:05:33 2019 ranaNotesFSSFSS Plant Model v2please overlay all the plots and also include
the ideal TFs - its hard to understand anything
without the comparisons
  
  2495   Thu Dec 12 19:15:55 2019 anchalDailyProgressFSSFSS Diagnostics - Beatnote Spectrum wrt Laser Power and Modulation IndexI took beatnote spectrums in the current
modulation index (was set to around 0.3 earlier).
Then I took spectrum after attenuating the
 BeatnoteSpectrumwrtPowerandModindex.pdf 
  2496   Fri Dec 13 16:24:02 2019 anchalDailyProgressFSSFSS Diagnostics - RFPD Circuit Latest Available PhotosI found the latest available photos for
the Cavity Reflection RFPD circuits.

 SN009.jpgSN010.jpgSN009.jpgSN010.jpg 
  2497   Fri Dec 13 17:44:05 2019 anchalDailyProgressFSSFSS Diagnostics - RFPD RF Coupled Output OffsetI rechecked the 20dB coupled RF output
of SN009 (RFPD on north Cavity reflection)
and SN010 (RFPD on south Cavity refleciton).
  
  2498   Mon Dec 16 09:43:56 2019 Ian MacMillanNotesFSSFSS Plant Model v2In talks with Anchal, we have adapted our
model and the transfer function fits rather
well. These measurements were taken with
 PZT_TF.pdfEOM_TF.pdfNon-Moku_Data_PlantCir_V1.zip 
  2499   Tue Dec 17 16:55:07 2019 anchalDailyProgressFSSFSS Diagnostics - TTFSS North U7 Boost Stage Input-Output TimeSeriesAs suggested few group meetings ago, I
took time series data at the input and output
of boost stage opamp U7
 NFSS_UT_TS_Analysis.pdf 
  2500   Tue Dec 17 18:29:58 2019 anchalDailyProgressFSSNeed for ISS?If we are going to keep the same laser
with busted Noise Eater, should be go in
the direction of implementing the ISS?
  
  2501   Wed Dec 18 14:04:43 2019 anchalDailyProgressLaserSouth Laser Power Dropped.After the last calibration, South Laser
power at Laser head determined by its internal
photodiode and show as setting PWR today
 SouthLaserPowerDropped.pdf 
  2502   Wed Dec 18 18:40:32 2019 anchalDailyProgressFSSMaybe the NPRO Laser isn't bad after allToday I inserted two photodiodes, Thorlabs
PDA10CS at (110,44)
at dumped end of a PBS before PMC and
 NorthLaserRINAnalysis.pdf 
  2503   Wed Dec 18 22:03:17 2019 ranaDailyProgressFSSMaybe the NPRO Laser isn't bad after allCould be that either


the FSS makes RIN through
driving the PZT / making beam jitter
FSS
  
  2504   Fri Dec 20 15:00:30 2019 anchalDailyProgressFSSPZT, EOM to RIN TF MeasurementI took some TF measurements, but I'm
not sure if I used the right method to do
this. All the resutls look essentially the
 NorthLaserPZTEOMtoRINTF.pdf 
  2505   Fri Dec 20 18:08:44 2019 anchalDailyProgressFSSPZT, EOM to RIN TF Measurement Through FSSTF Measurement Method


I
switched on Test1
switch on RF Board to cut off RFPD input
 NorthLaserPZTEOMtoRINTFThruFSS.pdf 
  2506   Mon Dec 30 10:33:33 2019 anchalSummaryOtherSummary of questions asked in DecemberFor the convenience of others, I'm
summarizing the open questions I asked on
elog in December. Comments on the posts,
  
  2507   Tue Jan 7 17:59:20 2020 anchalDailyProgressFSSNPMC TFMethod:


I
injected excitation at FP1Test
and readout at Mixer
 NPMC_TF.pdf 
  2508   Thu Jan 9 19:00:19 2020 anchalDailyProgressFSSTTFSS OLTFsI repeated this measurement to compare
later after changes to RFPDs.


 FSS_OLTF.pdf 
  2509   Mon Jan 13 19:04:38 2020 anchalDailyProgressFSSFSS Diagnostics - SN009 (North RFPD) Notch Improvement AttemptCircuit changes (Updated
Schematic)

I made
the following changes to SN009:
 SN009.jpgSN009_D980454-00-C.pdfSN009_Notch_Improvement_Attempt.pdf 
  2510   Tue Jan 14 13:30:39 2020 Ian MacMillanNotesFSSFSS Plant Model v2I made a more advanced model of the circuit
using Zero and compared them to the
experimental results.
 EOM_TF_V1.pdfPZT_TF_V1.pdfPlant_CIR_TF.zip 
  2511   Tue Jan 14 13:32:16 2020 Ian MacMillanNotesFSSFSS Plant Model v2I also designed a board for the circuit.
This is based on the Zero model from
the previous post.
 FSSPlantModelV2SCH.pdfFSSPlantModelV2.pdfPlant_Circuit_Board_Eagle.zip 
  2512   Tue Jan 14 18:19:33 2020 anchalDailyProgressFSSFSS Diagnostics - SN009 (North RFPD) Notch Improved!Circuit changes (Updated
Schematic)

I made
the following changes to SN009:
 SN009.jpgSN009_D980454-00-C.pdfSN009_Notch_Improvement_Attempt.pdf 
  2513   Thu Jan 16 11:17:15 2020 anchalDailyProgressFSSFSS Diagnostics - SN010 (South RFPD) Notch Improvement AttemptCircuit changes (Updated
Schematic)

I made
the following changes to SN009:
 SN010.jpgSN010_D980454-00-C.pdfSN010_Notch_Improvement_Attempt.pdf 
  2514   Thu Jan 16 20:18:44 2020 anchalDailyProgressFSSFSS Diagnostics - SN010 (South RFPD) Notch ImprovedCircuit changes (Updated
Schematic)

I made
the following changes to SN009:
 SN010.jpgSN010_D980454-00-C.pdfSN010_Notch_Improved.pdf 
  2515   Wed Jan 22 14:16:28 2020 anchalDailyProgressFSSTTFSS OLTFsRepeated these measurements after changes
to the RFPDs (Notch improved).

Inferences:


No
 FSS_OLTF.pdf 
  2516   Wed Jan 22 15:20:00 2020 anchalNotesBEATNotch improved on FSS RFPDs. Gain values increased as well.New Gain Values:

South
Common Gain: 24 dB , Fast Gain: 18 dB

North Common Gain: 14 dB, Fast
  
  2517   Wed Jan 22 16:00:26 2020 anchalDailyProgressFSSTTFSS OLTFs with Maximum GainRepeated these measurements with maximum
possible gain values in the FSS loops.


 FSS_OLTF.pdf 
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