"Dick Locke" wrote in message
...
OK, it's been one heckuva long time since I took EE courses but I do
remember that a square wave has a spectrum of *every* frequency. Why
do you pick on the odd harmonics as noisemakers?

Because a symmetrical square ware contains odd harmonics only, decaying in
amplitude . The fourier series looks like F + 1/3*3F + 1/5*5F + 1/7*7F
........

A sawtooth contains all harmonics like F + 1/2*2F + 1/3*3F + 1/4*4F......

Meindert