> Hi Kirk: My understanding is that a sloper working against a
> tower is a sort of dipole with the tower as one part and the
> wire as the other. I have found that the sloper usually must
> be greatly different in length than 1/4 wavelength to achieve
> a low SWR. The tower is very much part of the radiator. I
> think your tower is the main radiator and the sloper is a
> matching system which does very little radiating. I think you
> have a good system of loading your tower at present.
> 73, Dan, N5AR
Also, isn't whatever beam(s) you have on the tower top a significant factor,
acting as a tophat?
I noticed when I changed out a TH6 (damaged) for an A3 and later for an F12
C3E the my 80m 1/4-wave half-sloper was affected. I don't recall if I had
to lengthen or shorten it, but it did make a difference.
My sloper feedline and antenna node is on the very top of one of the legs of
my Rohn 25G pointy-top where it slopes to meet the mast tube.
Maybe that's Kirk's problem. His quad is not acting as much as a tophat for
the sloper as a beam might.
Kirk: I have heard of people extending a mast high enough above their
beam/quad for a wire antenna to clear. It's bizarre and I don't know if it
really works, but might be worth a look.
73,
Dale, kg5u
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