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Entry  Wed Jul 16 22:17:40 2014, Akhil, Summary, Electronics, Bode Plots and complete Characterization of Frequency Counter Phase_Data.zipBode100MHz.png
    Reply  Wed Jul 16 23:02:16 2014, Koji, Summary, Electronics, Bode Plots and complete Characterization of Frequency Counter 
       Reply  Fri Jul 18 19:32:50 2014, Akhil, Summary, Electronics, Filters used inside the Frequency Counter TheoreticalGainPlot.pngTFexpected.png
          Reply  Mon Jul 21 12:16:27 2014, Akhil, Summary, Electronics, Filters used inside the Frequency Counter FC_TF_Characterization.png
Message ID: 10223     Entry time: Wed Jul 16 23:02:16 2014     In reply to: 10222     Reply to this: 10239
Author: Koji 
Type: Summary 
Category: Electronics 
Subject: Bode Plots and complete Characterization of Frequency Counter 

If I assume 1sample delay for 0.1s sampling rate, the delay is Exp[-I 2 pi f T], where T is the sampling period.

This means that you expect only 36 deg phase delay at 1Hz. In reality, it's 90deg. Huge!

Also there are suspicious zeros at ~1.6Hz and ~3Hz. This may suggest that the freq counter is doing some
internal averaging like a moving average.

It would be interesting to apply a theoretical curve on the plot. It's an intellectual puzzle.

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