If you're comparing a ground-mounted 1/4-wave Marconi
to a roof-mounte Marconi, you're correct. Elevated radials
is a different scenario and probably the comparison would
then be to ground-mounted or even underground-mounted
radials where the location of [the base of] the antenna remains
unchanged.
The GAP is really a vertically-polarized 1/2-wave antenna with
tuning rods to provide the multi-band (and RG8X coax inside the
main tubing for 80/75 metre operation) capability. Radials, per se,
aren't required because there's no "missing" 1/4-wavelength to be
made up for, which is the case in the Marconi. The counterpoise,
whether the rigid box of the Titan or the three 57' wires of the
Challenger (the only two GAPs I've owned), is for increasing the
bandwidth of the antenna on one (specifically 40 metres) and possibly
more bands (allegedly 10 metres at least). Both my GAPs were ground
mounted and I had none of the mechanical or electrical failures which
have been mentioned on the reflector. This includes a few years of
being unguyed in Nevada, where 80 MPH winds are considered a light
breeze. Oops, let me reclarify this. The Challenger in Nevada developed
a 30-degree list and was replaced with the Titan. GAP indicated the tubing
could be brought back straight, but I figured it was a weak spot so let's get
another antenna. Although I had no comparison antennas, I was satisfied
with the performance of the Challenger while living near Denver, Colo. and
of the Titan while living near Carson City, Nev. For a number of reasons,
none related to performance issues, I am using a ground-mounted Cushcraft
AP8A in my present station near Seattle, Wash.
I personally do not consider these antennas dummy loads. However, everybody
is entitled to their beliefs and perception IS reality. Maybe I am ignorant of
the
fact that these antennas are dummy loads and that is why I am satisfied with
their
performance! I guess if I could compare them to a optimally spaced monobander
up
in the air a half-wavelength in relatively uncluttered aorspace, I too would
call them
dummy loads. Nevertheless, I have beaten stations I know ran more power and or
better antennas in the pileups. I have used nothing but verticals and dipoles
and
am satisfied with them.
73,
Bob AA0CY
----------
From: Dinsterdog@aol.com[SMTP:Dinsterdog@aol.com]
Sent: Friday, October 08, 1999 8:59 PM
To: aa0cy@nwrain.com
Subject: Re: [TowerTalk] GAP Titan
Bob, why would a vertical with elevated radials not work better than a
groundmounted vertical with a few ground radials??? Its what I would expect-
as would those who glamorize software splurts on antennas- hihi- but
seriously, the 2 s units sounds about right comparing your notes to my
expereinces with grnd mounted "dummy Loads" as in those grnd mntd antennas
with only a couple ground radials- 73 Paul N0AH
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