Hi Tom,
If you put a vertical with just one elevated radial on your rotator it is
nothing more then a bend dipol.
A dipol in theory might have 3db gain against a quarter wave as you doubled
the number of 1/4 elements.
Don´t expect real gain, just a little bit of directivity.
That directivy of course is the result of loss into other directions.
With decent height a horizontal dipole with its ground gain will outperform
that bend dipol and directivity will be even better.
Impedance close to 50 ohms suggests 14 ohms earth loss resistance and
results in poor efficiency otherwise with a true ground mounted quarter wave
vertical.
Resistance inserted into an atenna system extends the band width as well.
If you want a vertical antenna for any reason high in the sky use a J-pole
antenna.
73
Peter, DJ7WW now
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com] On Behalf Of Tom Osborne
Sent: Donnerstag, 12. Mai 2011 21:23
To: Towertalk
Subject: [TowerTalk] Vertical with 1 radial
Blank
Hi All
In the past 2 months, I have seen two different articles in ARRL
publications that say a vertical with 1 radial has gain in the direction of
the radial. One said 3 db. Evidently Eznec confirmed this.
Why the heck do I bother putting down all those radials under my verticals??
According to one article, 1 radial is best because it gives the antenna a
real wide bandwitch, SWR is close to 50 ohms, and has gain in the direction
of the radial. Seems like those symptoms would give loss not gain.
Is this true, or is the ARRL just publishing anything now? Sure is
different from anything I've ever known about verticals.
Seems like I should be able to put up an antenna with 1 radial on my rotor
and I could point it just like a beam. Fill me in. 73
Tom W7WHY
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