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Entry  Mon Feb 24 13:21:00 2014, Jenne, Update, Electronics, Measured REFL165 demod board  
    Reply  Mon Feb 24 17:59:31 2014, RANA, Update, Electronics, Measured REFL165 demod board  
Message ID: 9661     Entry time: Mon Feb 24 13:21:00 2014     Reply to this: 9666
Author: Jenne 
Type: Update 
Category: Electronics 
Subject: Measured REFL165 demod board  

I measured the REFL 165 demod board's I/Q separation. 

Our 11MHz signal is currently 11.066092 MHz, so I put a signal to the RF input of the REFL165 demod board at 165.992380 MHz (15*11 MHz + 1kHz), with a signal of -13 dBm.

I then used the SR785 to measure the transfer function between the I and Q output channels. 

I got 82.7 degrees, at -0.64 dB. (I don't remember now if I had I/Q, or Q/I, not that it really matters). So, it seems that the REFL165 demod board has good separation, and at least isn't totally broken.

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