Dave Barton, AF6S came up with a simple and elegant solution to the
Alpha RF choke 12m series-resonance problem a few years ago. His
solution was accomplished for a different model, but it sounds like the
same or a similar choke is involved.
Dave moved the series resonance, not by switching anything, but by
detuning it. He placed a closed ring of wire around the choke---a
shorted turn "transformer" winding. This moved the resonance away from
24.9 MHz and enabled operation there. Neat, and not gaudy.
I don't recall where on the RF choke he placed the turn--I have never
owned an Alpha, so that level of detail was irrelevant to me.
--
Garry Shapiro, NI6T
Editor, "The DXer," newsletter of the NCDXC
Visit the Northern California DX Club 50th Anniversary page:
http://www.aa6g.org/ncdxc50.html
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