----- Original Message ----- From: "phillip holmes" <insuranceman@xxxxxxxxxx>
A square wave on a record doesn't look like a square because of the velocity involved--or something--that I can't explain. A square wave is built up of stacked "odd integer harmonics" and contains multiple harmonics. Somewhere around 12 harmonics, it really looks like a square wave. The more harmonics present, the more perfectly formed the square wave becomes. A perfect square wave would require infinite bandwidth and infinitely fast electronics (forget the stylus, we can't even generate a perfect square wave, only a mathematical representation of one).
Now...let's assume we have a DC battery and a switch...so the output of the combination is either "current" (switch closed, DC voltage present) or "no current" (switch open, no DC voltage). We physically flip the switch between the two, say, five times per second. Since the voltage rises from zero to X as soon as the switch makes contact, don't we get a five Hertz "square wave?" Assume we have nice straight wiring (no inductance)...what, if anything, would distort the wave shape of our output?
Steven C. Barr