> Tom- what about a short or open end at the Balun ? I think he is doing
> everything to the beam, and not checking the other parts of the system.
Good point. If the cable is "messed up" at the balun or between the balun
and the meter, it can allow common mode current on the line. In that case,
changing line length might change SWR.
Common mode currents can be rooted in many causes. Hopefully the cable is a
good cable properly installed, and the balun is a good balun. What kind of
balun do they use, anyway? If it's a voltage balun (like most 4:1 baluns
are) it will do a crummy job of isolating the feedline from the antenna
unless the antenna is purr-fect.
73 Tom
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