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Entry  Fri Jul 18 17:10:57 2014, Nichin, Summary, Electronics, Characterization of demodulator boards. Demodulators_TF.pdf
    Reply  Tue Jul 22 15:50:35 2014, Nichin, Summary, Electronics, Characterization of demodulator boards. Demodulators_TF.pdf
       Reply  Wed Jul 23 11:54:27 2014, Nichin, Update, Electronics, Characterization of demodulator boards. 1.pdf2.pdf
Message ID: 10263     Entry time: Wed Jul 23 11:54:27 2014     In reply to: 10252
Author: Nichin 
Type: Update 
Category: Electronics 
Subject: Characterization of demodulator boards. 

Quote:

 

I repeated the exact steps above and made sure everything was back where it should be after I was done.

Reason I had to retake the measurements:

My script for acquiring data from the AG4395A network analyzer was such that it first acquired the magnitude data from channel 1 and then recorded phase data from channel 2 without holding its trace. Hence the phase and magnitude data were not exactly in sync with each other. So, when I tried to fit the data to a model using vector fitting, I ended up with very bad results.

I have now changed every single script relating to the network analyzer to just get the real and imaginary data in one go and then calculate the phase using this data.

The fitting process is now in progress and results will be up shortly.

The plots in the previous Elog includes delay and a little attenuation by RF cables and the RF mux.

Today I separately calculated the delay and attenuation for an RG405 cable (550 cm) and the RF mux(using really small RF cables). These delays should be accounted for when fitting the transfer function of Demodulator boards and transimpedance of PDs.

The plots are in both semilogx and linear.

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