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From: jfa0522@hertz.njit.edu (john f andrews ece)
Newsgroups: sci.electronics,sci.physics
Subject: Re: A question about the Nyquist theorm
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Date: 19 Feb 91 15:25:43 GMT
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an added practical note: after you get through all of the theory,
sample at about 2.5 or more times the Nyquist frequency to get everything
in your signal (you will have noise and such at up to there or so).

Of course better is to seriously prefilter your analog signal to well
below the Nyquist. This will ensure that all the nasties above your
*theoretical* Nyquist will be more than 78dB or so down and thus less than
1/2 LSB of you AD converter (assuming you are using one). Then the noise will 
be below the input threshold of the ADC.


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