In addition to the other questions, I'd like to know the range of the
air variable cap you are using. A range of around 20 to 40 pF at the
low end and 400 to 500 pF at the high end is good. Of course you can
add in fixed values in series and parallel to augment or change the
range so a more limited variable range is not necessarily bad (just
may be harder to use to find the match value). I think you said
something about it being fully meshed -- maybe you need to add some
fixed values? First, do the other things that have been suggested
like switching to 50 ohm feedline. fool with the cap range as a last
resort and if possible always measure your antenna Z at the feedpoint.
If you are measuring it at the tx end of your 75 ohm cable you'll go
nuts trying to figure out the problem.
Just a side note -- more shorter radials is probably better than a few
130 foot long ones. If it were me I'd cut the 130 foot radials in
half and double up with 65 footers, but that's just me.
rob / k5uj
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