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Re: sample rate
Tom Combs wrote:
> I thought the Nyquist theorem is all about reconstructing a signal
> once sampled. A signal is not reconstructed by simply "connecting the
> dots", it is reconstructed by passing it through a low pass filter.
> If you pass a sawtooth, triangle, square, or any other variety of
> periodic signal with frequency f through a low pass filter whose
> passband is perfectly flat up until frequency f, and then perfectly 0
> beyond f, then what comes out is a pure sine wave of frequency f -
> that's because squares, triangles and whatnot all contain harmonics in
> addition to the pure sine wave that dictates its fundamental frequency.
> A signal sampled at twice the Nyquist frequency can be perfectly
> reconstructed in a world of perfect filters and perfect sampling devices.