My experience loading 100 feet of Rohn 25G on top band fits with
what's being reported here about loading shunt-fed towers. At one
point, I decided to lower the resonant frequency of my tower by
connecting the top guys to the tower. They were insulated from the
tower and each broken with several more insulators on the way to the
ground. The tie-off point for the top-level guys was 2-3 feet below
the top of the tower, and I just jumpered over the top insulator on
each guy.
I was surprised to find that adding three guy sections, each 15-20
feet long, had no measurable affect on the resonant frequency of the
tower. Evidentally, the PRO-67B on top of the tower was carrying most
of the current. Everything below it was "just along for the ride."
Brad, KV5V
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