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Re: Analog to digital conversion - sample rate

Bob Amstadt wrote:

> It is a very interesting topic and for those of your interested in it, 
> I highly recommend that you take courses or do some experimentation.  
> It is a fun topic to explore.

I also recommend some historical background that is just amazing.

 From <http://www.lucent.com/minds/telstar/digital.html>:
Bell Labs researcher Harry Nyquist develops Sampling Theory. It states 
provides that if a signal is sampled at twice its nominal highest 
frequency, the samples will contain all of the information in the 
original signal.

When electrical engineers hear the name "Nyquist," they think of what 
Harry Nyquist is best known for: his Sampling Theorem. Evidence of its 
importance is everywhere. Products like cell phones, audio CDs, and 
iPods are all based on the broad-shouldered foundation of the theorem, 
and that alone is enough to place Nyquist among the industry's greats. 
But Harry Nyquist had many other, lesser known accomplishments, a number 
of which resonate strongly today.  (more...)

In 1927 Nyquist determined that an analog signal should be sampled at 
regular intervals over time and at twice the frequency of its 
highest-frequency component in order to be converted into an adequate 
representation of the signal in digital form. Nyquist published his 
results in the paper Certain topics in Telegraph Transmission Theory 
(1928). This rule is now known as the Nyquist-Shannon sampling theorem.