Roger wrote:
I am surprised at your criticism in using DC. To me, a square wave is
DC for a short time period. Is the observation that a square wave can
be described as a series of sine waves troubling to you? Perhaps the
observation that a square wave might include waves of a frequency so
high that they would not be confined in a normal transmission line is
surprising or troubling to you?

Anyone who has ever tried to send a DC pulse down a long
transmission line has seen AC ringing at the other end.
--
73, Cecil http://www.w5dxp.com