That's pretty heavy for a five element 20. I usually attach the
boom struts to a support mounted on the antenna boom. That way
you can tie your rope to the center of the boom and to the top of
the strut support to pull it straight up. The boom won't sag
because the struts are already attached and adjusted, and the
antenna can't turn because the pull rope is also attached to the
upper strut support. I have pulled up 60' boom antennas this way
using my SUV as the winch.
GL,
John
-----Original Message-----
From: 00tlzivney@bsuvc.bsu.edu
To: towertalk@contesting.com
Sent: 5/21/2001 12:43 PM
Subject: [TowerTalk] Topsy Turvy
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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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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