I don't think that I made myself clear the first time, so I will try again...
What I was wondering is how one attached lines used to keep the yagi
balanced horizontally (we call those tag lines) as it is coming down the
tram line. We use 1/4" EHS guy line cable for the tram line on a big
antenna and it attaches at the top of the tower to a chain wrapped around
the tower at the top. The boom of the antenna is attached to a pulley wheel
and hangs under the tram line. The antenna is held by a nylon line running
up from the base and through the gin pole to the antenna.
The part that I am wondering about are the lines that you use to keep the
antenna level as it comes down. Unless the antenna is hung perfectly, one
side of the boom or the other will be slightly heavier and we always use
small lines attached to the boom ends (or looped over the last element and
down to the ground) run by two men who tension the lines so the antenna
comes down the tram level (horizontal) to the ground.
That is an easy task on the way up because the tag lines can be looped
easily and tied to the boom to mast bracket. When the antenna is installed
and bolted down, we simply untie the lines, and let them fall to the ground
(or pull them up.... safer since they tend not to foul on the zippy trip
back to earth). The problem is how to get those control lines on when the
antenna is up and needs to come down. With a 48' or 60' boom, the boom ends
are 30' feet out and it is a random shot to try to get something to hook
appropriately at the end so that it does not come loose when the antenna
starts down the tram line.... I like the idea of a plow or torque bar to
keep the antenna coming down the tram line with barrel rolling... good idea.
So, does that make it clearer??
Gary
W5FI
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