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ID Date Author Type Category Subjectup Text Attachments
  4277   Sun Feb 13 02:33:37 2011 KojiUpdateElectronicsREFL11 Photodiode replacedSuresh is saying 375mW and 0.375mW. Let's
wait for his update of the actual power.
Also he is not using EPICS, there
  
  4279   Sun Feb 13 16:20:53 2011 SureshUpdateElectronicsREFL11 Photodiode replacedIt is 0.375 mW as in the calculation. 
The total diode output is just 1mW and it
is divided with a 50/50 beam splitter... 
  
  2761   Sat Apr 3 19:54:19 2010 AlbertoUpdate40m UpgradingREFL11 and REFL55 PDs Noise SpectrumThese are the dark noise spectrum that
I measured on the 11MHz and 55MHz PD prototypes
I modified.
 2010-04-03_REFL11_darknoise.png2010-04-03_REFL55_darknoise.png 
  9564   Wed Jan 22 09:05:42 2014 GabrieleConfigurationLSCREFL11 back Yesterday night I plugged back the
REFL11 RF cable into the corresponding demodulation
board.
  
  15923   Tue Mar 16 16:02:33 2021 KojiUpdateLSCREFL11 demod retrofittingI'm going to remove REFL11 demod for
the noise check/circuit improvement.

----
 IMG_0545.jpegIMG_0547.jpegD040179-A.pdfIMG_0548.jpegIMG_0550.jpeg 
  15936   Thu Mar 18 07:02:27 2021 KojiUpdateLSCREFL11 demod retrofittingAttachment 1: Transfer Functions

The original circuit had a gain
of ~20 and the phase delay of ~1deg at 10kHz,
 TFs.pdfPSD.pdf 
  4756   Fri May 20 11:37:44 2011 KojiUpdateElectronicsREFL11 fixed (REFL11 not working)- Found the inductor which shunts the positive
input of MAX4107 was not touching the ground.
 REFL11_transimpedance.pdf 
  4747   Thu May 19 03:13:54 2011 kiwamuUpdateElectronicsREFL11 not working
 1305799561ZgerKtrd.gif 
  4782   Thu Jun 2 23:10:10 2011 KojiUpdateElectronicsREFL11 test results (Re: REFL11 fixed)The full characterization of REFL11 is
found in the PDF.
Resonance at 11.062MHz
 REFL11_test.pdf 
  2704   Tue Mar 23 22:46:43 2010 AlbertoUpdate40m UpgradingREFL11 upgradedI modified REFL11 according to the changes
lsited in this
schematic (see wiki  / Upgrade 09
 2010-03-23_REFL11_model_to_meas_comparison.png 
  2711   Wed Mar 24 14:57:21 2010 AlbertoUpdate40m UpgradingREFL11 upgraded 
 Hartmut suggested a possible
explanation for the way the electronics transfer
  
  4272   Fri Feb 11 00:20:58 2011 SureshUpdateElectronicsREFL11: Photodiode requires replacement 
This is with reference to Kevin and
Jenne's elogs  # 3890,
 REFL11_10Feb2011.jpg 
  5101   Wed Aug 3 02:20:33 2011 KojiUpdateLSCREFL165 PDREFL165 PD has been made from the old 166MHz
PD.
As the required inductance was ~10nF
 REFL165_schematic_110802_KA.pdfP8031393.JPGP8031391.JPG 
  5112   Wed Aug 3 22:22:47 2011 KojiUpdateLSCREFL165 PDThis REFL165 was good in terms of RF, but
I forgot to make the DC path functioning.
I will try some ideas to fix this
  
  5121   Fri Aug 5 04:03:16 2011 KojiUpdateLSCREFL165 PDREFL165 PD was made and tested. The characterization
results are in the PDF file.
Resonance at 166.12MHz
 P8041394.JPGP8041395.JPGREFL165_test_110804_KA.pdf 
  6423   Fri Mar 16 06:17:56 2012 SureshUpdateElectronicsREFL165 calibration : measurements 
These are the measurements for estimating
the amplitude of the signal recorded in the
 IMG_0552.JPG 
  6425   Fri Mar 16 16:01:53 2012 ranaUpdateElectronicsREFL165 calibration : measurements To characterize the RF V to counts
we need to know the state of the whitening
filter board. Was the filter on or off ?
  
  6428   Mon Mar 19 21:25:31 2012 SureshUpdateElectronicsREFL165 calibration : measurements


   
        
            
  
  5678   Mon Oct 17 11:40:44 2011 KojiUpdateLSCREFL165 removed from the tableREFL165 removed from the table for the
C(V) test
  
  5681   Mon Oct 17 22:20:42 2011 KojiUpdateLSCREFL165 removed from the table

    

       
            
  
  5685   Tue Oct 18 10:04:41 2011 KojiUpdateLSCREFL165 removed from the tableThe original REFL165 had ~50MHz/A dependence
on the DC photocurrent.
The resistr R21, which was 2670 Ohm
 REFL165_original.pdfREFL165_new.pdfREFL165_schematic_111017_KA.pdf 
  6333   Tue Feb 28 16:31:08 2012 SureshUpdateElectronicsREFL165 repair: CharacterizationThe transfer function and current noise
were measured.  The location of the
peak shifts with the amount of incident light
 REFL165_Characterization.pdfREFL165_response_shift.pdf 
  6339   Wed Feb 29 01:14:40 2012 SureshUpdateElectronicsREFL165 repair: Characterization

    

       
            
  
  6337   Wed Feb 29 00:22:35 2012 SureshUpdateElectronicsREFL165 repair: Installed on the AS table1) The REFL165 has been replaced onto the
AS table.
2) When the PD interface cable is
  
  6290   Thu Feb 16 21:13:07 2012 SureshUpdateElectronicsREFL165 repair: PD replaced, DC response checked with a torch light[Koji, Suresh]
Kiwamu mentioned that REFL165 is
not responding and its DC out seems saturated
 PC_30641_old.jpgPD_30641_new.jpgIMG_0548.JPG 
  6418   Wed Mar 14 16:39:02 2012 SureshUpdateGeneralREFL165 signal was not reaching demod board : Fixed

    

       
            
 Test_CDS_Calibration.png 
  5086   Mon Aug 1 23:26:32 2011 KojiUpdateLSCREFL33 PDOld MZ PD (InGaAs 2mm, @29.5MHz) has been
modified for REFL33.
There has been no choice for the 11MHz
 REFL33_schematic_110801_KA.pdfP8011390.JPG 
  5113   Wed Aug 3 22:31:38 2011 KojiUpdateLSCREFL33 PDREFL33 is ready for the installation
Characterization results of REFL33
is found in the PDF attachment.
 REFL33_test_110801_KA.pdf 
  6411   Wed Mar 14 04:19:51 2012 kiwamuUpdateLSCREFL33Q for MICH control : not good I tried the REFL33Q for controlling
MICH in the PRMI configuration (#6407)
 Untitled.png 
  3952   Fri Nov 19 03:43:33 2010 KevinUpdateElectronicsREFL55 Characterizations[Koji, Rana, and Kevin]
I have been trying to measure the
shot noise of REFL55 by shining a light bulb
  
  3955   Fri Nov 19 15:51:50 2010 KojiUpdateElectronicsREFL55 CharacterizationsRF Transimpedance of 200Ohm means the residual
impedance at the resonance (R_res) of 40,
  
  4605   Tue May 3 04:09:53 2011 KojiUpdateLSCREFL55 PD update[Rana, Koji]
REFL55 was modified. The noise level
confirmed. The PD is now ready to be installed.
 REFL55.pdf 
  4845   Mon Jun 20 18:36:49 2011 SureshUpdateLSCREFL55 PD update[Suresh, Koji]
   I used a matlab code
written by Koji to analyse the transimpedance
 REFL55_response.pdf 
  3944   Thu Nov 18 01:52:58 2010 KevinUpdateElectronicsREFL55 Transfer FunctionsI measured the optical and electrical transfer
functions for REFL55 and calculated the RF
transimpedance. To measure the optical transfer
  
  2715   Thu Mar 25 17:32:42 2010 AlbertoUpdate40m UpgradingREFL55 UpgradedI upgraded the old REFL199 to the new REFL55.
To do that I had to replace the old
photodiode inside, switching to a 2mm one.
 2010-03-25_REFL55_model_to_meas_comparison.png2010-03-25_REFL55_model_to_meas_comparison.png 
  15990   Fri Apr 2 01:26:41 2021 gautamUpdateElectronicsREFL55 chain checkout again, seems fine[koji,
gautam]

Summary:
  
  13276   Wed Aug 30 19:49:33 2017 gautamUpdateLSCREFL55 demod board debuggingSummary:

Today
I tried debugging the mysterious increase
in REFL55 signal levels in the DRMI configuration.
 REFL55_demod_check.pdf 
  15871   Fri Mar 5 16:24:24 2021 gautamUpdateLSCREFL55 demod board re-installed in 1Y2I don't have a good explanation why,
but I too measured similar numbers to what
Koji measured. The overall conversion gain
 REFL55.pdfdemodNoise.pdf 
  15855   Tue Mar 2 19:52:46 2021 gautamUpdateLSCREFL55 demod board reworkThere were multiple problems with the REFL55
demod board. I fixed them and re-installed
the board. The TFs and noise measured on
  
  15859   Wed Mar 3 22:13:05 2021 gautamUpdateLSCREFL55 demod board reworkAfter this work, I measured that the orthogonality
was poor. I confirmed on the bench that the
PQW-2-90
  
  15864   Thu Mar 4 23:16:08 2021 KojiUpdateLSCREFL55 demod board reworkA new hybrid splitter (DQS-10-100) was
installed. As the amplification of the final
stage is sufficient for the input level of
 D990511-00_REFL55.pdfP_20210304_215602.jpgP_20210304_222400.jpgP_20210304_222412.jpg20210304234400_IMG_0526.jpg 
  15867   Fri Mar 5 13:53:57 2021 gautamUpdateLSCREFL55 demod board rework0 dBm ~ 0.63 Vpp. I guess there is ~4dB
total loss (3dB from splitter
and 1dB from total excess loss above theoretical
  
  15869   Fri Mar 5 15:31:23 2021 KojiUpdateLSCREFL55 demod board reworkMissed to note: The IF test was done at
TP7 and TP6 using pomona clips i.e. brefore
the preamp.
  
  8412   Thu Apr 4 10:32:42 2013 GabrieleSummaryLSCREFL55 error signalsThe attached plot shows that also the behaviour
of the REFL11 and 55 signals is qualitatively
equal to the simulation outcome.
 prmi_refl_signals.pdf 
  8413   Thu Apr 4 10:46:54 2013 KojiSummaryLSCREFL55 error signalsBeautiful double peaks. I don't see the
triple zero-crossings. Is this because you
adjusted the phase correctly (as predicted)?
  
  2789   Mon Apr 12 16:20:05 2010 AlbertoConfiguration40m UpgradingREFL55 improvedDuring the commissioning of the AS55
PD, I learned how to get a much better rejection
of the 11MHz modulation.
So I
 2010-04-12_REFL55_TF_model_to_meas_comparison.png 
  4622   Wed May 4 12:07:48 2011 SureshUpdateRF SystemREFL55 installed on the AP tableREFL55
has been installed on the AP table. 
REFL11 has been moved to make space for a
  
  11208   Wed Apr 8 13:26:47 2015 ericqUpdateLSCREFL55 signal back to its normal ADC inputsAs the POP55 demod board is actually demodulating
the REFL55 signal, I have connected its outputs
to the REFL55 ADC inputs. Now, we can go
  
  13280   Thu Aug 31 00:52:52 2017 gautamUpdateLSCREFL55 whitening board debugging[rana,gautam]  REFL55_whtCheck.pdfREFL55_whtChk.tar.gz 
  15977   Mon Mar 29 19:32:46 2021 gautamUpdateLSCREFL55 whitening checkoutI repeated the usual whitening board characterization
test of:


driving a signal (using
 REFL55wht.png 
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