sample points

[labnoob]

What determines the point at which an analogue waveform  is sampled. E.g. say I have a live 1 HZ sine wave, and record it above Nyquist, say at 5 Hz. Whats to say I don’t end up taking my 5 samples on the x axis, i.e. at 0 amplitudes? Something I have always wonderd is all.

Many thanks

[crossrulz]

---

@labnoob wrote:

What determines the point at which an analogue waveform  is sampled.

---

Luck of the draw.  A sample is taken when the digitizer's clock tells the ADC to take a measurement.  So, yes, if you sample a sine wave exactly at Nyquist, you can get all 0s.  The likelihood is next to nil.  But that's also why we say to go way above Nyquist if possible.  Your 1Hz signal sampled at 5Hz should be just fine.  It will at least get the peak and valley.