There is nothing special, a 50 feet high dipole has at 25° elevation angle
the same gain as a shortened vertical over lossy ground or with just a few
radials.
73
Peter
-----Original Message-----
From: Topband [mailto:topband-bounces+dj7ww=t-online.de@contesting.com] On
Behalf Of Roger Kennedy
Sent: Montag, 16. März 2020 13:52
To: topband@contesting.com
Subject: Topband: NVIS Antenna
Well I've said it dozens of times before . . . but I have used a horizontal
halfwave Dipole (at about 50ft)
for working DX on 160m for the past 50 years ! (and that's at 6 different
QTHs)
Not only do I work all over the world, but I know my signal often compares
pretty well with other Gs using good verticals . . . and I have no problem
getting through the pile-ups working the various DX-peditions.
How is this possible? Well in my opinion it's because DX propagation on
160m ISN'T like 80m (where it IS nearly all low angle, so you MUST have a
good vertical to work DX effectively)
Based on the hundreds of comparison QSOs I've had over the decades, I figure
that on 160m, propagation MUST be fairly high angle a lot of the time,
presumably because of inter-layer reflections or ducting.
Most of the "experts" who have written books about Low-band DX-ing have made
the assumption that 160m is just like 80m . . . which in my experience it
clearly isn't !
The only other factor I DO think is that if you have a low dipole on 160m
but DON'T have any radials or anything underneath it, it probably radiates
more low angle than computer-modelling software would suggest. I believe the
errors occur on 160m because it can't properly forecast the effect of the
REAL WORLD ground when the antenna is a fraction of a wavelength above it.
Roger G3YRO
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