> http://abelian.org/ebnaut/ebsynth.shtml

I squared up the soundcard output with a Schmitt trigger and the
3rd harmonic of 45.9 kHz comes out very nicely at 137.7 kHz.
Also the 7th harmonic of 68142.857143 Hz gives a nice pure
note at 477 kHz on my scanner.  Right now I'm listening to
the 53rd harmonic on 80m and it still sounds quite clean.

EbNaut sounds very chirpy when listening to a harmonic as
the phase rapidly slews from one symbol to the opposite one.
The 7th harmonic is going through 3.5 cycles each time.
I'll have to add another command line option to specify the
phase change so that a selected harmonic will have the right
180 degree shift.

--
Paul Nicholson
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