[Elecraft] KPA/KAT100 Problem "solved"

[Don Wilhelm]

Even with a 1.2 SWR, there will be a change of feedpoint impedance with a
change in the line length - and yes, the SWR on the line will not change by
a measurable value.  (On a truly flat line - SWR=1 - the feedpoint impedance
will not change with length)

Whether a small change in line length is significant or not depends on the
frequency - 3 feet is a small fraction of a wavelength at 80 or 40 meters,
but at 10 meters, it is close to a 1/8 wavelength change (depends on the
velocity factor of the feedline) and that is quite significant.

Looks like you stumbled onto the 'magic' length for your antenna system!!!
('Magic' = whatever makes it work right)

73,
Don W3FPR

----- Original Message -----
> Though the solution is not really terribly satisfying. In the
> process of trying to isolate the problem I inserted another
> SWR/power meter in the transmission line between the
> KAT and the antenna. Not a problem, everything worked just
> fine. Removed the meter and problems return. Huh? BUT, it
> wasn't JUST the meter, it was an extra 3 feet of coax too.
> Well, remove the meter but put the coax back in and problems
> go away!  The indicated SWR on the line is 1.2:1 with the
> extra 3 feet of coax or not.
>