Gilmer, Mike wrote:
>
> If the antenna/load impedance (at the far end) in question here doesn't
> match the line impedance, then the line will transform the impedance,
> and the SWR will vary (as seen at the near end) depending on the cable's
> length, correct?
I think the correct way to put this is that the impedance seen looking into the
line will vary with the length. However, the theoretical swr will be constant,
regardless of the point at which it is measured.
In addition to the various issues of imperfect meters, etc., that have been
mentioned, common-mode currents ('antenna currents') flowing on the outside of
the coax can affect swr measurements big time. They are caused by feeding
balanced antennas directly (i.e., without a balun), or by coax that runs closer
to one side of an antenna than the other, etc.
Please don't bother sending me 'baluns are worthless' replies; I have an email
filter that sends them directly to the bit bucket.
73,
Vic, K2VCO
Fresno CA
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