> Brad KV5V wrote:
> I can only report that many years ago a professional antenna
> engineer (and ham buddy) in Dallas strongly recommended that I route all of
> the coax and control lines inside the tower. His reasoning: coax outside
> the tower becomes part of the radiating element when you load the tower,
> and applying high power can physically stress and damage the coax. At a
> more practical level, having the coax inside the tower offers some
> protection from surges in the electric field around the tower when
> lightning is in the area.
I run the open wire tuned feed line to my dipole attached to the tower at
the 119' level, up through the inside the tower,
spaced at the geometric centre of the triangle using plexiglass strips every 10
feet.
The tower is 127' tall, base insulated and serves as a quarter wave vertical
Tee for 160,
working against extensive buried radial ground system. The dipole serves as the
horizontal portion of the Tee, coupled to the vertical tower via the proximity
of
the OWL through its entire length. I have had this system in place since 1983
and
has always been very stable.
Not a sprig of coax anywhere in the entire system.
Don k4kyv
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