In a message dated 99-04-11 18:34:36 EDT, tomwagner@mindspring.com writes:
> 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 just built an X-9 myself for our tribander comparison test and I
don't think there's any way you could build it on a tower. Check out our
presentation at Dayton if you want to find out how it did performance-wise.
>
> 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.
>
This is obviously an advanced technique so unless you're a
professional or highly skilled amateur, don't do it. The recent post by
Howard, AK9F, was an excellent recap of how to do it properly.
The BEST discussion of techniques for this kind of problem is in Tom
Schiller, N6BT's book , "Array Of Light". He has a whole chapter on ways to
thread yagis through guy wires. He uses a technique he calls 'wig wag' and
several others. The book also includes many other discussions of antenna
design and LOTS of practical tips and information from one of the best
electrical and mechanical antenna designers around. Call 800-248-1985 for a
copy; it's ten bucks.
Cheers, Steve K7LXC
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