[ARC5] HF Converter - feeding mixer with a square wave?

[Leslie Smith]

        HF converter - 80M to BC-453 tunable IF.

I wish to build a simple solid state converter to bring the lower part of
80m down to suit a BC-453 working as a tuneable IF.   The LO frequency
would therefore be 3200kHz.  Crystals are readily available for 6400kHz.
Consequently I am considering dividing the crystal frequency by 2 using a
JK (or similar) digital divider.   This raises a question.  Normally a
mixer is driven with (something approximating) a sine-wave - a signal with
no harmonics.  A digital divider provides a square wave, with many odd
harmonics in the signal.  The amplitudes  of the harmonic fall
progressively, so that the third has an amplitude of one third the
fundamental.  The fifth fifth - one fifth and so on.  You can check this
easily using MS excel spreadsheet.  (or just trust Mr. Fourier).

Question:  How will the presence of these harmonics affect the operation of
the mixer.  Will a square wave produce a "family" of intermodulation
signals that I find undesirable?  Am I chasing the wrong birdie up a tree?

Leslie

PS - 3200kHz crystals are available, but not so easily got as crystals for
6400kHz, so the idea of using a sine-wave isn't out of the question.
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