I have recently completed construction of a moderately large antenna -
48 foot boom with 5 elements for 20m and 2 heavily beefed up 402CD elements.
This weighs about 250 pounds.
The problem is that when I lift the boom with a sling, the antenna wants
to roll around the boom so the elements are vertical. This has happened
several times, regardless of how I adjust the slings. It is stable in
the horizontal position, but only a slight tilt in either direction around
the boom causes it to go vertical. All seven elements are mounted on
the bottom of the boom. There is a boom strut above the boom with
3/16 EHS guys and real galvanized turnbuckles. I have measured that
each element is indeed centered on the boom.
I have never experienced this before. In the past I have trammed the
antennas up so that the pull line would have kept the antenna with
the proper attitude so I may not have noticed this tendency. This time,
I was trying to pull the antenna up the side of the tower in a vertical
pull and was going to pull the antenna away from the tower a moderate
amount where necessary to clear lower antennas and perhaps temporily
drop a guy (like I understand W9RE does). But this tendency to\
go vertical means that I need over 44 feet of vertical clearance between
antennas to get this sucker on the tower!
Any ideas?
Terry Zivney, N4TZ/9
List Sponsor: Champion Radio Products - We'll be at the Dayton Hamvention
with all of our safety equipment and other products. Stop by booth #559 and
say hi.
<A HREF="http://www.championradio.com";>www.ChampionRadio.com</A>
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