AD5VJ Bob wrote:
> For raising the three element tribander:
> Any ideas on homemade gin poles, I can not afford to buy one right now.
>
>
Although I have used a gin pole for raising and they do work well a
pulley up top should do almost as well. The only thing missing with the
single pulley is the offset which puts the rope out away from the side
of the tower. I built my own from two sizes of steel tubing and steel
plate, but it requires a welder and it is heavy. OTOH it's designed to
handle a lot of weight. I need to put together some photos of the mounts.
The problem with this approach is having to rotate the tribander
http://www.rogerhalstead.com/ham_files/TOWER24.HTM around the guy lines
although a 3L should be easier than a 5L. I'd use two pulleys. One up
top and one at the bottom of the tower. The reason for the one at the
bottom is it allows your helper (who really does the work of lifting the
antenna) to walk out away from the tower where it's safer and it
eliminates putting a side force on the top mast or gin pole.
http://www.rogerhalstead.com/ham_files/tower.htm (Photo of the top of
the gin pole about half way down the page....IT's a big page!) My
system is a bit different with a 2:1 mechanical advantage as you see a
pulley attached to the antenna. This shouldn't be necessary with the
weight of a single three element tribander.
If possible I'd create a tram line. I prefer two tram lines about 8 feet
apart with pulleys hanging from them but that is getting a bit elaborate
for a single tribander.
With the single pulley up top on the mast above where you'll mount the
tribander and a pulley at the base of the tower, your helper can lift
and hold the antenna while you rotate it around the guy lines. As long
as the guy levels are far enough apart this is a fairly easy procedure
with the smaller antennas.
Good Luck es 73
Roger (K8RI - ARRL Life Member)
www.rogerhalstead.com
N833R (World's oldest Debonair)
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