Re: square wave harmonic theory (time domain)


It would be hard to sample and FFT such as to resolve the 100,000th
harmonic of any waveform.


I was only kind of talking a theoretical ADC. Even though there are ADC's up
in the Giga samples per second, lets talk about a theoretical test with an
ADC that samples at 1Gsps with 24 bit resolution (kick-ass ADC). If I took a
1 KHz square wave and triggered my ADC on the rising edge of the
pulse...delayed a bit waiting for the transistor to settle (say
200uS)...then took 65536 samples (65uS) of the steady state and did an FFT
on them...what would I see? In the time domain it would appear I was
sampling DC. If the FFT shows high frequencies relating to 1KHz where are
they coming from?

Thomas



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Relevant Pages

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  • Re: square wave harmonic theory (time domain)
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