In article ,
Ralph Mowery wrote:

I have seen many plots of inverted V and flat top dipoles, but none of a
V or U shaped one.

That is like one I have up for 80 meters. I have two trees that are
about 20 feet short of the distance I need for an 80 meter dipole. The
trees are so that I can get the wire up about 60 to 70 feet on the ends
and the middle is only about 35 to 40 feet above ground.


Here's a different suggestion. Put up as long a section (horizontal
except for the sag) as you can between the two trees. Say you can get
115 ft that way. Then extend each end 10 ft by adding a vertical wire
dropping down. Now the high current point on 80 m is way up in the air
where it will do the most good and the antenna won't be as much of a
cloud-warmer as your non-inverted V would have been.

Yet another suggestion: Just put what you can up there between the two
trees. So it's 20 ft or so short. Feed it with home-made open wire
(second choice: ladder-line). Use a good tuner. The main problem with
antennas slightly short of a half-wave long is that they have relatively
low resistance and appreciable capacitive reactance so feedline losses
go up. But if you use really low loss feedline they can still be pretty
good. For use on harmonics there is some advantage to avoiding an actual
half-wave on 80 m since that will have very high impedance on even
harmonics and with some feedline lengths can be very hard to match.

David VE7EZM and AF7BZ

--
David Ryeburn

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