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[TowerTalk] GAP Titan

To: <towertalk@contesting.com>
Subject: [TowerTalk] GAP Titan
From: aa0cy@nwrain.com (Bob Wanderer)
Date: Fri, 8 Oct 1999 20:44:38 -0700
Apparently some folks have never heard of Loctite(TM).
Works wonders on British motorcycles and GAP verticals.

The GAP is a vertically-polarized half-wave dipole.  Radials
are unnecessary.  The counterpoises increase the frequency
coverage on some of the bands (I think 7 MHz and below) and
can be left off if necessary.

A 1/4-wave vertical (Marconi) needs radials to provide the "missing"
quarter-wave.  100+ is the best for a ground-mounted antenna.  As
you raise the base of the antenna, fewer and fewer radials are required.
At single family dwelling roof heights, four per band (if a multi-band type)
is all that's needed.  I typically double that if I can.

While comparisons can be suspect, I once had a situation where a co-worker
and I (in norhtern NJ) were in a 40-metre phone QSO with the same 
station in central Texas.  We both ran the same rig, output power and 
antenna (the Hy-Gain 40~10 trapped vertical, I forgot the part number), 
except his was ground-mounted with three 8' ground rods and mine was up 
in the air about 16' with six 1/4-wave+5% radials per band.  According to the
receiving station, we were two S-units difference in signal strength, with mine
being the louder.  Oh yes, we lived about three miles apart with similar
topography and ground type.

You either love or hate an antenna, car, etc. from your experiences or those
of friends.  Perception is reality.  I had a Ford passenger car which was a real
dog so I've never since bought a Ford passenger car; but I think their trucks
and vans are the cat's meow.  Agree or disagree as you wish.  Once again,
remember that perception IS reality.

73,
Bob AA0CY


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