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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