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Entry  Wed Nov 4 23:17:51 2009, Alberto, Update, LSC, X Arm Cavity transfer Function ArmCavityTF02.png
    Reply  Thu Nov 5 05:07:22 2009, rana, Update, LSC, X Arm Cavity transfer Function 
       Reply  Thu Nov 5 19:25:11 2009, Alberto, Update, LSC, X Arm Cavity transfer Function PDA255CalibrationTF03.png
Message ID: 2178     Entry time: Thu Nov 5 05:07:22 2009     In reply to: 2177     Reply to this: 2184
Author: rana 
Type: Update 
Category: LSC 
Subject: X Arm Cavity transfer Function 

I would have guessed that you have to calibrate the detectors relative to each other before trying this. Its also going to be tricky if you use 2 different kinds of ADC for this (c.f. today's delay discussion in the group meeting).

I think Osamu used to look at fast transmission signals by making sure the PD at the end had a 50 Ohm output impedance and just drive the 40m long cable and terminate the receiving end with 50 Ohms. Then both PDs go into the SR785.

 

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