A vertical dipole can have shortened elements, making height less of an
issue. Force 12 used to make sideways H shaped verticals that were center
fed. I have used one on 40m and it was surprisingly good. Here is a
Force12 80m Sigma vertical:
https://dxsupply.com/en/amateurradio/verticals-6-80-m/force12-80m/
John KK9A
David Gilbert ab7e wrote:
"Assuming you have the height"
That's the kicker, though, and it takes twice as much of it for
relatively little additional performance. I've modeled a 20m ground
plane with four elevated radials and a 20m vertical dipole, both of them
being 4 feet off the ground. The elevation pattern is lower with the
vertical dipole (17 degrees versus 23), but the maximum gain is almost
identical.
I agree that your suggestion (feedpoint at the bottom with a serious
choke) is a practical way to make a vertical dipole, but you have to
trim for tuning at the top whereas you can trim a ground plane at the
radials near the ground.
73,
Dave AB7E
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