> The 6-12 degree region contains the first arrival angle distribution
> peak. It takes a dipole at 160' to put much energy there. A vertical
> isn't the answer to cover these lower angles -- unless you have excellent
> ground conductivity. EZNEC shows that verticals are also poor performers
> at these angles there in areas of conductivities in the 2-5 range (my QTH
> is 2.5.) Of course, if your vertical antenna is on a salt marsh, you win.
Modelling prompted me to install a 318 ft tower, and that probably
was one of the worse investments I ever made. But hey, if you don't
try one you never know. Don't sell a vertical short without trying
one, at least not on the lower bands where things may work out
better than you expect!
On 1.8MHz, I have a dipole at ~300feet. At best it just ties a series-
fed 200ft tower. Most of the time the 200ft tower is better, and
that's true at any distance!
My soil does not seem to be particularly good, it is clay with a thin
layer of sandy topsoil although this is gentle rolling pastureland and
woods.
On 80 meters at my old QTH near Atlanta, a 35 foot top loaded
vertical with 60 80 foot radials tied or beat a 100-120 foot high
dipole into Europe night after night.
I hope to have an 80 meter vertical up here someday to test against
my 160 foot high dipole. Of course I always use real ground
systems with lots of radials.
73, Tom W8JI
W8JI@contesting.com
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