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Old January 13th 07, 12:16 PM posted to rec.radio.amateur.antenna
Roy Lewallen Roy Lewallen is offline
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First recorded activity by RadioBanter: Jun 2006
Posts: 1,374
Default Better for DX: Vertical or dipole?

The T is simply a top loaded vertical. The top portion radiates an
insignificantly small amount for the same reason ground plane radials
don't radiate. (Hey, wonder if they act as an "image" mirror to reflect
the signal into the ground?) (That was a joke.) The horizontal portion
of an L antenna radiates like any end fed horizontal wire. If it's low,
most of the radiation is at a high elevation angle.

Roy Lewallen, W7EL

wrote:
Cecil Moore wrote:

Performance wise, I don't think you could tell the real
vertical from the T except for the T's lower feedpoint
impedance.
--
73, Cecil,
http://www.qsl.net/w5dxp

The T is better if he wants it to act like a DX vertical.
The L is ok, but if the horizontal wire is fairly long,
there will be a good bit of horizontal radiation.
This can be good for a mix of NVIS and DX, but
for DX only, the T is usually better. The T will have
an overhead null the same as a normal monopole.
I'd say most peoples L's on 160 have more horizontal
wire than vertical... :/ I know mine did. I could only
get mine about 45 ft vertical . That left 80-90 ft running
across the backyard. I often feed my coax fed dipoles
as a top hat vertical on 160 by shorting the coax, and
feeding as a vertical. At the moment I have a turnstile on
80m, and a dipole on 40. "6 legs total"
The 4 60 ft wires make a good "X" top hat..
MK