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Re: Topband: High and low angles

To: <topband@contesting.com>
Subject: Re: Topband: High and low angles
From: "Doug Waller" <NX4D@comcast.net>
Date: Sat, 5 Mar 2005 08:21:54 -0500
List-post: <mailto:topband@contesting.com>
>There are definitely times when it takes a 10 dB back seat
>on long-haul DX to a simple inverted-V which is optimized to radiate
>straight up.

The vertical and inverted-V both radiate poorly at 40-45 elevation degrees. 
I would think that these radiation angles may be more useful than straight 
up.  There are relatively unrecognized antennas that can produce optimum 
radiation at 40-45 degrees.

The W8JK dipoles, fed 180 degrees out of phase, and at a height of 1/8 
wavelength or more, produce a pattern that looks good for 160m DX.  More 
recently Belrose, VE2CV, wrote an article for QST, August, 2002, about his 
horizontal loop design, broken into two loops, and fed 180 degrees out of 
phase.

These horizontal antennas need to be 1/8 wavelength high or higher to 
develop the lower angle radiation patterns.  Great advantages for the little 
gun with his house, driveway, and streets preventing a good radial field, is 
that horizontal electrical lines are reflected from the ground surface with 
high efficiency at most incidence angles.  This is truly a case where a 
complete lack of radials should make little difference in performance.

Verticals, by their nature, swamp 50 percent of their radiation resistance 
potential.  But horizontal radiators give us 100 percent of the radiation 
resistance available.

As receive antennas, horizontally polarized antennas reject power line and 
other local noises.  I believe we need to take another look at these 180 
degree out of phase horizontal antennas.

73, Doug / NX4D


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