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Old October 1st 08, 09:12 PM posted to rec.radio.amateur.moderated
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First recorded activity by RadioBanter: Jun 2006
Posts: 147
Default Use of ground wires underneath dipoles

In article ,
Bill Horne wrote:

According to Wikipedia
(http://en.wikipedia.org/wiki/Near_Ve...dence_Skywave), a
horizontally-polarized NVIS antenna will benefit from a ground wire
underneath it.

Here's an excerpt:

"An NVIS antenna configuration is a horizontally polarized (parallel
with the surface of the earth) radiating element that is from 1/20th
wavelength ... to 1/8th wavelength above the ground. That proximity to
the ground forces the majority of the radiation to go straight up.
Overall efficiency of the antenna can be increased by placing a ground
wire slightly longer than the antenna parallel to and directly
underneath the antenna. While the ground wire is not necessary under
good to excellent propagation conditions, antenna gain in the 3 dB to
6 dB range are common when the ground wire is used."

Since I've never heard of anyone doing this, or seen any hams trying it,
I'd like to hear from those who've done it, and find out if the gain is
as predicted.

73,

Bill W1AC, who is rushing to get a good sky-hook up before the winter


We used a configuration of that principal, for years, when doing
communications for the Ididarod DogSled Races out in the bush
of Alaska. Put up a Dipole for 80 Meters, strung between the trees,
and then ran a Grounded Wire, directly under the Dipole, that was 3%
longer, electrically. Increased our ERP for Short Range Comms.
Typical Ranges were from 120-500 Miles. KL7BB can give you any details,
you could require, if you can track Crazy Bill down......