> verticals over nearly all openings, all conditions. I've never,
> repeat never, seen a situation that would remotely support a 20+db
> difference due to antenna polarization! This includes both signals
> I've sent and those received, in comparison with others in nearby
> areas, etc. etc. Big differences CAN exist in path conditions, for
Typically I see large repeatable differences ONLY when comparing a
low dipole (around 100 feet or less high) with a high dipole or
vertical over a path several hundred miles long or longer.
The average difference, over the past three years or so in many
directions, is slightly in favor of my vertical when compared to a
high dipole (~300 feet). A low dipole is consistently ten dB or more
down from both the high dipole and vertical.
The exception is *virtually always* at sunrise peaks and during
severe geomagnetic disturbances.
> top band stations. Contests, as you know, also wring out things pretty
> well. I think there are several things working as far as understanding
> 160 meter antenna effectiveness. The first, of course, is efficiency.
> With verticals this means length of radiator plus percentage of near
> field coverage (radial field) plus fresnel zone effects.
My suggestion is people who simply can't make a vertical work have
many things adding up wrong, not one major flaw like latitude. There
is a strong human tendency to blame every result on one simple cause,
and to oversimplify vastly complex problems.
24dB is about the difference between my eight-foot mobile antenna and
my 200 foot vertical. When I had a N/S dipole, I never received
reports that indicated the dipole had the performance of a mobile
whip...ever.
As a matter of fact, N and S I had about the same results as E and W.
A 15dB difference, let alone 24 dB, would stand out like a sore thumb
even if you were NOT looking for it. 73, Tom W8JI
W8JI@contesting.com
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