Use skirt feed here with considerable success. I have a 70' tower with a
40M beam on top, and I use skirt wires to "shunt feed" the tower on 80 and
160. It has worked well; I use 4 wires, spaced out about 3 feet from the
tower. I have suggested such feed to several fellows with little
interest. By using such feed one can get a wide variety of matching
options which are often easier to make up.
There is another forgotten variation--in my old Antenna Engineering text
I believe it is Therman who shows a wire dropped down thru the center of
a tower, which is then fed at the bottom thru a network. That idea would
be great for large cross section towers.
As mentioned, the same method can be used to de-tune a tower or
sectionalize it without using an insulator.
Ralph Matheny
K8RYU
207 Gibbons Place
Marietta Ohio 45750
mathenyr@marietta.edu
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