I A-B or A-B-C tested several antennas, including a low dipole, the high
dipole, an element from my four square, a ~318 foot insulated tower
vertical, and I think my tall omni vertical was about 190 feet at that
time.
The tall vertical tower was definitely worse compared to shorter
verticals, and had almost no short skip signal around Georgia. I had
isolation chokes for lights and a base insulator, but that 300+ foot tower
was so poor I never used it as a vertical.
That may have been confusing. I never got in the habit of calling my 300ft +
insulated tower a tall vertical, because I always considered it a support.
It did have isolation chokes for cables and lights and a base insulator. It
worked its way up in height from doing radial tests until it eventually
reached ~318 feet.
The vertical I call a tall vertical has always been a 180-200 ft insulated
vertical, so it is not really the tallest vertical. It was just the one that
worked best as a tall vertical.
The really tall tower was so poor for overall use I just grounded the base
when I rebuilt it with Rohn 65G a few years ago, so now it is no longer
available as a series-fed structure. It has a ground system around it that
allows other test antennas, and for a while I had two four squares. Since
the 300 ft gets hit by lightning at least once in every storm, it is too
much trouble to have cables run out to a four square with ground radials.
Lightning current melted an LMR400 cable shield every other storm.
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Topband reflector - topband@contesting.com
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