I just bought a Cushcraft X9, and have been thinking about
how to raise it. Tramming is out, I just don't have enough room.
I had resigned myself to building it on the tower -- a prospect
that took another X9 owner 6 hours. Ugh! The X9 has a
28' boom, 9 elements and the longest element is 36'
I was browsing KC1XX's web site and found an idea that
intrigues me. He raised W4AN's new 40m beam by walking
it up the tower and detaching/reattaching guys as he went.
Has anyone done this? Here is how I would envision it:
Element tips pointing up, walk the beam
(with gin pole assistance of course) to
the first guy level. Attach a temporary guy wire just below the
boom and tighten a come-along until the first torque bracket bolt
comes out easily. Move the antenna past the first guy level, and
reattach the old guy. Remove the temporary guy and move to
the second guy level. Repeat the procedure at each guy level.
Questions:
1. Is an ordinary come-along safe for this purpose? If it gives way,
the tower will be subject to unbalanced forces and could collapse.
Should the guys be loosened at each level, before using this
approach? Would two temporary guys be better than one?
2. My tower is 75' of Rohn 25 guyed at 3 levels with 1/4" EHS,
somewhat over-guyed, but well within spec for downward stress.
3. Does this seem safer than spending 6 hours on the tower?
It sure is less work.
Has anyone used this approach. I'd like to do this safely, but
without 6 back-breaking hours at the top of the tower. Even
if it took longer than 6 hours to do it right, it would be better
than building it at the top. It would also be better, in that
I could test it at the first guy level for proper operation and
correct problems much more easily than using the other
approach.
Please post replies to the reflector.
Tom Wagner, N1MM
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