AW: Harmonix content formula

[Haible Juergen]

	>Is there some formula for working out the harmonic content of any
wave? and 
	>conversly is there a formula for re-constructing the wave?

Sure, it's called Fourier Transform, and Inverse Fourier Transform ...

It will work on any periodic or non-periodic waveform, but the bad thing is
that
it involves some ugly integration. (Details should be in any good textbook.)
If you're asuming periodic waveforms only, the formula simplifies a little,
from
integral to (infinite) sums. Still not my favorite kind of equations (;->).
In *practice*, you will normally use tables of fourier transorms for a small
number of 
basic waveforms, and get the result for your desired signal with another
small number
of basic operations like time delay, linear combinations and so on.

I rarely do this manually since I have PSpice with built in FFT.

JH.