For dipoles, typical yagis, etc, the resonance of an antenna is the
frequency(s) where the feed impedance at the antenna is non-reactive. At
that point the resistance may or not be 50 ohms. Then if it is not (assuming
50 ohm feedline and instrumentation), the
point of minimum SWR as seen on a meter in the shack will move when coax
lengths are changed. Point of a meter's minimum swr indication and antenna
resonance do not necessarily coincide.
73, Guy.
From: Rich Hallman N7TR <N7TR@Rnodx.Org>
> I have an issue I have had for quite some time. I can move the resonant
> point of my 2el 40 cc by 100Khz by changing the feed line length. I
> just installed all new LMR-400 and I still have this problem. Replaced
> the coax balun with a W2DU type and still have the same problem.
>
> Is this normal??
>
> Thanks...
> Rich
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