Way back there was a discussion about knots and some marine or knot web sites
were mentioned.
I tried to avoid using tag lines while lifting antennas. I was blessed to
have Bertha, no guy wires and had to do my antenna work just by myself. In
order
to simplify the installation of antennas on the tower, I used short "mast"
attached to the boom to mast plate. From the top of that mast I would run boom
guys. This allowed properly tension the boom guys on the ground level and level
the boom (62 ft). Then the block and tackle was attached to the top of the
short "mast." There was a small loop (with carabiner) from the block going over
the pulling line which managed to ride on the pulling line. I could pull away
from the tower by controlling the angle of the pulling end. This way antenna is
nice and balanced and no need for tag lines. I would lift it up to the
mounting level, tie the pulling rope and go up and put the mast clamps. XYL
would
untie the rope and I would pull the block down (safety "declaimer" too).
With guyed towers you might need the tag lines to maneuver the antenna around
the guys.
Yuri, K3BU.us
In a message dated 2/23/04 4:39:27 PM Eastern Standard Time,
n4zr@contesting.com writes:
This past weekend I was on a ground crew putting up two large 40m
yagis. Because the tag lines needed to be reachable from the tower, they
were attached only maybe 18 inches from the center of the boom, which made
it very hard to apply enough force on the tag lines to control the antenna
(lever arm too short).
I seem to recall reading, at one time, about a special type of knot
designed for remote untying. In a nutshell, it holds tight as long as the
"untying" force is applied through the loop formed by the knot, but a good
tug on a "pigtail" sticking out of the knot itself will cause the knot to
untie. It occurred to me that such a knot could have been used to attach
the tag lines some distance from the center of the boom, with the pigtail
taped to the boom and long enough to reach to the center, so that the tag
lines could be released when no longer needed.
Am I making this up, or does someone know the details or, perhaps, a web
site source?
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Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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