I have found the Tram method of raising Yagi's to be one of the
easyest way vice trying to feed them up through the guys. The hardest
work is getting the rigging ready.
For antennas in the TH7 weight class I use a 5/16' black
Dacron/Polyester double woven rope for my tram. For the bigger
monobanders then I would consider a steel tram. The ground end of
the tram is attached to the front of my truck. A come-along here
would work as well, but I simply move the truck to tension the tram.
I have two different types of slings (depending on the Yagi to be hoisted).
On the monobander I use u-bolt with saddle around the boom,
then an angle iron held my the u-bolt. Next I attach a small chain to
a hole in the angle. One on either side of boom center and joined in the
middle. The other method I use is a simple Tuflex sling around
the boom on the outside of the two closes elements to the boom/mast
plate.
On the tram I use a single tackle block with a hook and safety latch
to attach both ends of the sling. My pull rope is also attached
to the tackle block. This rope goes through another tackle block
up on the gin pole just below the tram attachment point. Pull rope
then dropes down to the ground.
Make sure your gin pole is strong enough to handle the load, if in doubt
back guy it. For heavy loads I have just started using
Rohn 25 it works great. And, if your shorts are tight you can climb it.
73 Pete N4KW
p.s. I live 70 miles north of Tampa. If you want to see this first
hand I am presently starting to attach the rigging to raise a 5el 15m
above my 5el 20. Come on by I can use the help.
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