> Yes, it would seem a bit improbable for a system like this
> to just happen by accident, although as the IEEE paper
> points out, it is theoretically possible, which was, in and
> of itself, news to me.
A major point of all this is whether the effect is common or even
occasionally occurs at HF, or even is possible to occur without
special circuitry.
In over 30 years, I've never seen it happen. I've never seen a half-
frequency signal appear in a PA or non-linear system of any sort with
the system having an oscillator. I've watched plenty of spectrum
displays and short of instability in PA's and transmitter systems
have never seen the effect.
> Whether you believe its due to parametric division, super-
> harmonic injection locking, or some other less esoteric
> mechanism (like a D flip-flop), the tracking relationship
> between the 14 MHz fundamental and the 21 MHz
> spurious suggests that an F/2 component is coming from
> something (either in the transmitter or receiver).
Of course it is coming from something, the question is what is it
really coming from. I suspect it could be products from mixing with
some intentional or unintentional oscillator.
> David, please let us know what you find out with regard
> to the 3F/2 mystery. I am really curious to understand
> what is causing it.
I'm interested in the cause also. It is an odd and rare problem.73,
Tom W8JI
W8JI@contesting.com
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