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Entry  Thu Aug 12 17:34:37 2010, Megan, Summary, NoiseBudget, Noise Budget NoiseBudget.figNoiseBudget.png
    Reply  Fri Aug 13 15:10:33 2010, rana, Summary, NoiseBudget, Noise Budget 
       Reply  Fri Aug 13 15:47:36 2010, Megan, Summary, NoiseBudget, Noise Budget BeatSignal.pngNoiseBudget.pngNoiseBudget.fig
Message ID: 279     Entry time: Fri Aug 13 15:10:33 2010     In reply to: 276     Reply to this: 280
Author: rana 
Type: Summary 
Category: NoiseBudget 
Subject: Noise Budget 

Quote:

Sorry, here's a prettier graph! I think the strange bumps in the low frequencies is from very few samples in that region and the interpolation matlab is trying to do. Once I have more data to compare it to, I'll try to figure out how to get rid of them.

 It looks a little like the FFT was done wrong here. How about uploading some more details, e.g. what is the channel names used? Is this in the DAQ or just using the SR785? How about a diagram showing what the transmission PD is, what the range of the Marconi is, how the signal goes to the DAQ, etc, etc, etc.....

Don't we need a whitening filter to put the PLL control signal into the DAQ? Or I guess we can use a DC channel and an AC coupled, high gain channel.

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