On Tue, 30 Sep 2008 18:39:02 EDT, 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.
I have a chain-link fence along my property line. Maybe I can move my antenna
over to the property line and use the fence as ground wire.
73,
Bill W1AC, who is rushing to get a good sky-hook up before the winter
73, Dick, AC7EL in Southern Nevada, who is waiting for November or later to do
his antenna work. It was 95 degrees Fahrenheit today, still too hot for outdoor
work for this transplanted New Hampshirite. BTW, it almost never snows here.
73 de Dick, AC7EL