Steve, VE6WZ wrote:
"Why does it screw things up ?? I am curious, since running the cables
inside my tower is not an option since the tower is kept down when I'm
not QRV....it will go up and down many times a week. Just working DX
with an antenna is not proof that it is working as well as it could, but
my cables just hang from the top and it seems to play well enough....I
seem to be able to work most DX I can copy. Been working for 3 years.
What is the thesis here ??"
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When I said "screws things up", I was thinking about those cases where
the cables go horizontally away from the tower over to the ham shack,
i.e., they leave the tower at the top of the first tower section rather
than going all the way down to the ground before leaving the vicinity of
the tower. There's no telling what ill effects this would have on the
radiation pattern and efficiency on 160m.
Ideally, the cables would be taped every few feet to a tower all the way
down to the ground. This would make the cables be tightly coupled to the
tower and therefore they would be electrically a part of the tower
structure as far as shunt feeding goes. Therefore they would have no
influence on the structure's electrical height and (more importantly) on
the radiation pattern and efficiency on 160m.
The next best thing to taping the cables to a tower leg is to let them
dangle down to the ground inside the tower. This would also couple the
cables to the tower and allow the cables to go up and down while the
tower is cranked up and down.
You said your cables just hang from the top of the tower. I assume that,
when the tower is fully extended, the cables are quite close to the tower
and come all the way down to the ground before they leave the vicinity of
the tower. This method should also be ok.
73, de Earl, K6SE
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