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Entry  Thu Jul 17 16:39:34 2014, Nichin, Update, Electronics, PDFR debugging attempt : REFL11 REFL11_17-07-2014_154534.pdfREFL11_17-07-2014_154534.zip
    Reply  Thu Jul 17 17:39:57 2014, Koji, Update, Electronics, PDFR debugging attempt : REFL11 
Message ID: 10229     Entry time: Thu Jul 17 16:39:34 2014     Reply to this: 10232
Author: Nichin 
Type: Update 
Category: Electronics 
Subject: PDFR debugging attempt : REFL11 

In a attempt to debug the values of transimpedance generated by the PDFR system, I did a manual measurement for REFL11 PD.

  • Took the tops off AS and POY tables. (REFL11 and REF PD) Under the supervising eye of Manasa
  • Verify that no extra light is falling on REFL11.
  • Retake DC voltage readings, power readings.
  • Manually set the sweep parameters and record readings from network analyzer.
  • Put the tops back on the tables
  • Calculate transimpedance 


REF PD(1611):

Pinc = 1.12 mW                 T_dc = 10000 V/A (datasheet)

Vdc = 7.68 V                      T_rf = 700 V/A (datasheet)

Calculated Responsivity = 0.68 A/W (Which matches perfectly with the datasheet value of 0.68 A/W) 


Pinc = 0.87 mV             T_dc = 66.2 V/A (schematic)

Vdc = 32.5 mV      

Calculated Responsivity = 0.56 A/W



Network analyzer reading at 11 MHz : 0.42

Calculated RF Transimpedance = 460 V/A

40m Wiki : RF Transimpedance = 4 kV/A

I ran the same measurement using PDFR system and got the same results.

Attached: the automatic data and plot obtained.

Conclusion:  The PDFR system and manual measurements agree with each other. However the values do not match with 40m Wiki. I have no clue about which measurement is correct or any mistakes I might be making in the calculations. 


Attachment 1: REFL11_17-07-2014_154534.pdf  31 kB  | Hide | Hide all
Attachment 2: REFL11_17-07-2014_154534.zip  18 kB
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