"Richard Clark" wrote in message
...
Hi Ken,
I don't see much advantage of one over the other, much less getting
into the benefits of BalUns and ladder line.
Any particular ratio only works if you actually observe that ratio
between line and load or source. This is unlikely if you are using
the antenna as an all bander (a distinction that is suspect in spite
of testimonials). A true all bander comes with issues, and knowing
those issues and responding to them allows all band operation.
However, you can achieve that status with a simple hank of wire, less
the appelation. In other words, you already have an all bander in
your dipole. It couldn't possibly work worse (or better) than the Van
Gordon except through choice of placement. In that regard, higher is
better, and it would seem you have plenty of length already.
IF it doesn't work (because it is whole wave on one band or the other)
you simply pair up a second in parallel (literally at the feed point)
and move on. The sad fact of it is, once you have a decent dipole up
(yours comes close enough), you have to invest many, many more dollars
and step up to a tower and beam to get to the next tier of
performance. Let's face it, few if any have towers supporting 80M
beams (and not many more with full-sized 40M beams).
On the other hand, 12 feet away from the feed point is awfully close.
This means you are literally part of the loss of the system (like a
hamster in a microwave). On the plus side, any high SWR would hardly
offer much loss over such a small run. However, such proximity often
leads to Common Mode issues (does your system refuse to tune some
bands? Even to folding back power?).
73's
Richard Clark, KB7QHC
The current antenna will tune up quickly and easily on all bands
from 160-6 meters. I was having some instability problems untill
I tied all equipment grounds to the copper baseboard heater pipe.
Before I did that I would see SWR changes when touching my
rig, my SWR meter, my tuner etc. Not now. I know the hot water
pipe is not supposed to be a good ground but this is working
extremely well.
So, how do you suggest I handle the transition between my coax
run from the tuner and the 450 ohm ladder line?
73's de Ken KG0WX
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