On Mon, 11 Sep 2006 15:27:58 -0400, KC1DI quoted the entire bloody message
to add two paragraphs. Bummer. But he made some excellent suggestions.
I have several comments.
First, I shouldn't even tell you anything good -- being on the east coast,
you've got at least 10 dB on us over here on the left coast going into EU!
But seriously, the first thing I would try is a half-wave (or even a
loaded half wave if you don't have enough height in the desired direction)
dipole sloping off the tower. Expect to see a few dB of gain over a dipole
in the direction that it slopes. A ham in PA sells very nice loading coils
that will shorten a dipole quite nicely under the name of Hypower Antenna
Co. Google or look in QST to find him. They handle my Ten Tec Titan just
fine.
The vertical angle patterns of a sloping dipole are discussed in ON4UN's
book. At W6BX, where we have a 150 ft tower and ground sloping down away
from the tower, I have a two-wire sloping dipole cut full size for 80 and
40, with HyPower loading coils to make it resonate on 160. It plays VERY
well on all bands.
Second, the antenna system that KC1DI is talking about is thoroughly
described in either the ARRL Antenna Book or the ON4UN book (or maybe
both). It's basically four half slopers coming off the side of the tower,
with some switching to change directions as needed.
I think that both of these antennas, as well as the single half sloper,
have fairly good low vertical patterns.
The sloping dipole does NOT need a ground plane, and it is completely
insulated from the tower, but the tower operates a bit as a reflector for
it. ON4UN's book says that you can vary the angle of the antenna to vary
the vertical pattern.
73,
Jim Brown K9YC
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