Jim ..... yes, that is exactly the system I use ..... the Dacron line
holding the center pulley is a continuous loop over a limb. A second Dacron
line going to the antenna's center insulator runs through the pulley. I do
not use pulleys or anything special at the ends. The ropes at each end of
the antenna just go over a tree limb and down to an eye-hook at the base of
the tree.
One thing the separate loop/pulley in the center does is to allow some
"play" at this point. It is not a rock-solid connection to the tree so it
swings back and forth a little bit. This system also makes it real easy to
lower the center of the antenna. You have a way to pull down the center if
something happens to the feedline or if you just don't want to pull on the
feedline.
This helps a lot when the wind blows and the trees start to wiggle.
All I can say is that it works and you don't have to fool around with
buckets of sand and other stuff.
-------------------
Wes Attaway (N5WA)
(318) 393-3289 - Shreveport, LA
Computer/Cellphone Forensics
AttawayForensics.com
-------------------
-----Original Message-----
From: TowerTalk [mailto:towertalk-bounces@contesting.com] On Behalf Of Jim
Brown
Sent: Friday, August 12, 2016 1:38 AM
To: towertalk@contesting.com
Subject: Re: [TowerTalk] Weight on ends of a OCF diploe
On Thu,8/11/2016 10:02 PM, Roger (K8RI) on TT wrote:
> 5/16ths is over 1700# strength, but a bit more expensive.
FWIW, I use the 5/16-in rope because it's easier to grab hold of to pull
tension on my very high dipoles. 3/16-in (and even 1/8-in) is plenty
strong enough for most antennas that aren't very high.
Wes, N7WS, described a system similar to one I rigged here soon after I
moved here, with help from Ira, K2RD, and others. I replaced it with the
system of pulleys that I now use because it allowed me to get the
antennas higher, and it also allowed me to rig a 20/15/10 fan in line
with the 80/40 fan that had loading coils for 160.
The system that Ira showed me how to rig had a continuous loop of
5/16-in that he launched over a limb with his pneumatic tennis ball
launcher (he cleared the tallest redwood on my property -- about 175 ft
-- by at least 10 ft on the first shot). To that loop he attached a
pulley, then pulled the support wire through the pulley, then pulled the
pulley it all the way to the top.
That system survived at least one winter without a weight, because there
was enough "give" in the way the pulley was rigged to allow for sway,
but I'm not confident that the loop rope would have survived over that
limb for 10 years. :) Wes's experience suggests otherwise.
73, Jim K9YC
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