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ID Date Author Type Category Subjectup Text Attachments
  2780   Wed Apr 7 10:58:15 2010 KojiUpdateElectronicsREFL11 Noise SimulationWhat??? I don't see any gray trace
of Rs in the plot. What are you talking about?
Anyway, if you are true, the circuit
  
  2781   Wed Apr 7 11:11:19 2010 AlbertoUpdateElectronicsREFL11 Noise Simulation


   
        
            
 rfpd11_testinput_noiseplot.pdf 
  2782   Thu Apr 8 10:17:52 2010 AlbertoUpdate40m UpgradingREFL11 Noise Vs PhotocurrentFrom the measurements of the 11 MHz RFPD
at 11Mhz I estimated a transimpedance of
about 750 Ohms. (See attached plot.)
 2010_04_05_REFL11_ShotnoiseVsPhotocurrent.png 
  2783   Thu Apr 8 10:24:33 2010 AlbertoUpdate40m UpgradingREFL11 Noise Vs Photocurrent


   
        
            
  
  2784   Thu Apr 8 20:53:13 2010 KojiUpdate40m UpgradingREFL11 Noise Vs PhotocurrentSomething must be wrong. 
1. Physical Unit is wrong for the
second term of "Vn = Vdn + Sqrt(2 e
  
  2785   Fri Apr 9 06:45:28 2010 AlbertoUpdate40m UpgradingREFL11 Noise Vs Photocurrent


   
        
            
  
  2790   Mon Apr 12 17:09:30 2010 AlbertoUpdate40m UpgradingREFL11 Noise Vs Photocurrent


   
        
            
 2010-04-09_REFL11NoiseMeasurements.png 
  2795   Mon Apr 12 22:44:30 2010 KojiUpdate40m UpgradingREFL11 Noise Vs PhotocurrentData looks perfect ... but the fitting
was wrong.
Vn = Vdn + Z * sqrt( 2 e Idc )
  
  3890   Thu Nov 11 02:17:27 2010 KevinUpdateElectronicsREFL11 Photodiode Not Working[Koji and Kevin]
I was trying to characterize the
REFL11 photodiode by shining a flashlight
  
  3893   Thu Nov 11 07:26:03 2010 AlbertoUpdateElectronicsREFL11 Photodiode Not Working


   
        
            
  
  4275   Sat Feb 12 08:08:05 2011 SureshUpdateElectronicsREFL11 Photodiode replacedA new photodiode ( Perkin and Elmer Model
no. C30642GH Sl No.1526) has been installed
in the place of the old photodiode. 
 C30642_datasheet-1.pdf40mUpgradeREFL11schematic.pdfP2120572.JPGP2120565.JPGP2120571.JPG 
  4276   Sat Feb 12 23:22:21 2011 ranaUpdateElectronicsREFL11 Photodiode replaced375 mW is way too much light. We must never
put more than 100 mW on any of these diodes.
We don't want to blow up more diodes like
  
  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 
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