Re: how to analyse a waveform?
"Max Fazio" <faxiomas@xxxxxxxxxxx> wrote in message
news:445f503b$0$14776$4fafbaef@xxxxxxxxxxxxxxxxxxxxxx
Hi all , first post here.
I'd like to make an harmonic and DC bias analysis of the waveform coming
from a synthesizer's VCO; I'd like to make an analysis of the sine output
,
which features some extra harmonics though, but I want to get the best
result possible, that is without any influencing artifact coming from the
audio output.
How can I do that? What tools should I use?
How healthy is your bank account?
At a bare minimum, an oscilloscope tops the list.
To accurately measure complex waveform parameters, you need a scope with a
readout to avoid interpolation and parallax evaluation errors. It also
makes the job much quicker.
Cursor scopes are widely available now, but can be hard for some to use.
Sencore scopes use a separate display apart from the crt, and I'm very fond
of mine.
If you want to directly compare different waveforms, you'll want a DSO
(Digital Storage Oscilloscope).
A good quality spectrum analyzer can be a big help.
A tunable harmonic distortion analyzer helps measure harmonic levels.
Generally, with audio gear, this is displayed as a percentage. Again, with
a scope readout, you can zero in on specific waveform components to measure
amplitude, frequency, deltas, etc.
Good luck!
.
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(comp.dsp) |
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