Could someone please direct me to documentation (either Velleman or otherwise) explaining the output of the spectrum analyser. I presume the Y axis is voltage and the waveform represents amplitude over a range of frequencies but at what frequencies as there is no apparent Y axis scale? I also understand a perfect sine wave would show a peak at only the sine wave frequency but a square wave would show many peaks, they representing the harmonics making up the square wave(?).
[quote]I presume the Y axis is voltage and the waveform represents amplitude over a range of frequencies[/quote]You are right.
[quote]but at what frequencies as there is no apparent Y axis scale?[/quote] Y axis show the amplitude in decibels (dB). Please select View -> Markers.
Marker function for absolute and relative voltage measurement is provided. The absolute voltage level in dBV or the voltage difference in decibels (dB) can be measured.
[quote]I also understand a perfect sine wave would show a peak at only the sine wave frequency but a square wave would show many peaks, they representing the harmonics making up the square wave(?).[/quote] Yes, you are right.