> I have not tried a vertical dipole on 40m, but can
> report somewhat similar results with a 40m quarter
> wave vertical versus a horizontal dipole at about 40'.
> The vertical was in the clear and had about 60 radials
> - that should lead to over 90% efficiency.
>
> The vertical was consistently 1-2 S-points worse than
> the dipole at any distance and in any direction.
Me too. The only place I get a 40M vertical to nearly equal
a dipole at 60-80ft is when the vertical is a hundred feet
in the air.
80M is better, but the vertical only really shines on 160.
My 80M dipole at 150 feet would tie or slightly beat W4AN's
four square on 80.
On 160 a dipole at 300 feet is about equal with a 200 ft
vertical with 100 200 ft long radials in the dipoles FAVORED
directions at distance greater than a few hundred miles. The
vertical of course KILLS the dipole off the ends of the
dipole.
> Then I moved the vertical so that it is now amid some
> trees about 50' from a reasonably sized lake (~12miles
> x 0.5mile) - it had previously been about 400' from
> the lake. It is now at least the equal of the dipole
> at any distance and in any direction, and distinctly
> better for DX.
I get a similar effect with enough height. My antennas are
mounted over Georgia clay, in open slightly rolling pasture
land. No trees or obstructions within a few hundred feet in
any direction. Even in this open loaction, I'd take a
horizontal dipole any day of the week over a vertical on 40M
or higher. Less so on 80, and not at all on 160.
> I can sort of understand that the vertical now has a
> better ground plane extending over many wavelengths
> which presumably improves its performance. I can't
> understand why that is still true in February when the
> lake is frozen to at least 5' down and ice is a very
> poor conductor.
Less ground clutter around the antenna?
73 Tom
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