n3rr@erols.com wrote:
>Lee, your method as described says: "rope" and "string". That will not
>work! It requires Steel-rope for the tram/pulley arrangement and
>"rope" (I use 1/2 inch poly) to pull the antenna up the tram cable.
>
>The steel tram cable needs to be significantly tensioned to support even
>a medium size beam to a reasonable height. I tensioned my tram cable
>(3/16 stainless steel rope) to 1000 Lbs tension (as measured with a LOOS
>tension gague) to haul up my 40-2CD to 67 ft. Tensioning to anything
>less sagged too much to pull the antenna up!!
I've used both steel wire-rope and good regular rope for the tram line.
I tend to favor the regular rope for the following reasons:
1) Easier to work with.
2) Non-metallic; SWR check can be done on the antenna while hanging
from the tram line.
A good 1/2" braided rope like Yale Double Esterlon has very little
stretch, and a tensile strength of 10,000 lbs. Highly recommended
for all tower work.
Yes, keeping the antenna above the top guy can be a problem.
The method I've settled on, in most cases, is to run the tram
line directly above the top guy in one direction, tension it,
and then drop that top guy (letting it hang straight down the
tower). The tram line takes the place of the guy wire.
As soon as the beam reaches the tower, the guy wire is reattached,
the tram line is removed, and the beam is raised the rest of the
way.
--
Steve Maki K8LX
steve@oakcom.com
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