Re: Harmonic on Homebrew RF Transmitter

dgc wrote:

> > Any clipping at the output stage will generate some 3rd harmonic.

> I don't see evidence of clipping in the waveform.

Clipping is taking things to an unecessary extreme. All that would be
necessary for substantial harmornic distortion to occur would be for
the amplifier to become slightly non-linear at the greater excursions
of the sine wave. It doesn't have to literally clip, just become a
little more rounded off on top than a sine wave would be, but to a
smaller degree than you could possibly see on the scope.

Incidentally, a 40m wire dipole (or derived antenna) will operate
fairly well on the 15 meter band, so any third harmonic you don't keep
from the antenna will go world wide. Get the exciter operating in a
legal part of the 15 meter band and you can use this to advantage.

.

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