Peter, thanks for the input. And Cebik also suggested 1700 pF or so as
a starting point for the 160M link. I am currently using a 3" coil with
five turns cut out of the center as the link. It's not as effective as
a concentric link, but the SWR is very responsive to the output
capacitor and I do see 50 ohms and about zero reactance at the tuner
input. It occurred to me that the link capacitor was added to the early
link tuner designs as a refinement, and I'm wondering if, with my
particular combination of component values, a link capacitor is
necessary at all.
Nevertheless, thanks for confirming that it tunes fairly flat. That
gives me the confidence to go forward.
Peter Chadwick wrote:
>K2XX asks: Is this relative insensitivity for the series link typical?
>The usual 'rule of thumb' is that the link should be the same reactance as the
>transmission line, or about 50 ohms. This will tune with about 1800pF on 160,
>and will have a Q of around 1, so you can expect it to tune fairly flat. You
>do want a fairly tight coupling between link and tuned circuit, though.
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