Grant, you should consider putting in an additional 23 radials and put the
radial system on or in the ground. This will eliminate any possible detuning by
the big metal building and interaction with the RX 4 square. You said that your
vertical T will go up to 85 feet. However, by elevating the radials 10 feet,
your effective vertical distance is 75 feet which will allow you to shorten the
top hat wires a bit. As an alternate, you could put down 1/8 wavelength radials
on the ground but more of them and have a good system too.
If you must go with an elevated radial system, I recommend that you read the
articles by Dick Weber, K5IU, who strongly advocated elevated radials shorter
or longer than 1/4 wavelength. If shorter, then the radials are loaded with a
small coil. If longer, then they are tuned out with a capacitor. W5UN uses
shortened elevated radials on his 160 meter 4 square with great results. They
are about 70% of a quarter-wave in length.
73, Dennis W0JX/8
Milan OH
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Topband reflector - topband@contesting.com
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