Ted, I though others could get use out of this method, so I
hope you don't mind that I copied the TowerTalk reflector.
>just a quick question....i was just reading a msg of yours concerning your
>probs with adjusting a KT34XA on 15m....did you ever get that resolved??
Yes, after a ton of adjustment.
>my real question is....after you re-built the beam, u mentioned pointing it
>in the air (director at top, reflector at bottom with elements parallel to
>ground)...
>
>you mentioned having it 9 to 15 ft off the ground....how did u suspend the
>beam in that position to do your swr measurements with the analyzer??
And I did it by myself!!!
Started with the beam laying on the ground, pointing away from the
tower, between two guys. Reflector about 6-10' from the base of
the tower.
A pulley/gin pole was at the top of the tower. The rope came down
off of that and attached to the director end of the beam. I had
another smaller rope attached to the same point on the yagi. It's
just coiled up on the ground for now.
The first time up, I hoisted up the big rope so the beam was still
sitting on it's reflector. I then took the smaller rope and went
away from the antenna/tower with it. I was out about 80' or so
(for my 100' tower and 32' boom yagi). I then tied the small rope
to a stationary object with about 3 feet of slack. How far out
you tie the small rope and how much slack you leave in it will
depend on how high your pulley/gin pole is, and how long of a boom
on your yagi is. (If you have a 40' tower and a 30' boom, this
method won't work too well.)
I then went back to the large rope (gin pole or pulley) and
continued hoisting up the yagi. As you hoist it up, the tension
on the smaller rope pulls the antenna away from the tower as
it goes up. The more you hoist it up, the more the yagi moves
away from the tower. Be careful, as you'll get to the point
where you can't go any further.
At this point, my reflector was 10'-15' above the ground and
the whole yagi was at least 15'-20' away from the tower. Not
only was that good for electrical reasons, but it also kept
the yagi from entangling in the guy wires.
After measuring the antenna and it's time for it to come down,
do not detach the smaller rope. Just let down the large rope
until the reflector is back on the ground. Then make
sure that as you give it a little more slack, that the beam
wants to tilt away from the tower. With the extra weight of
the smaller rope biasing it in that direction, my 20 attempts
always tilted in the correct direction.
After it's back on the ground and you've made any corrections,
it goes right back up without adjusting any ropes.
I tied the big rope to my lawn tractor. I hoisted my 32' boom
yagi in the air over 20 times this way, by myself. Easy.
>will it make a difference if u just rest the reflector on the
>ground with the antenna aimed to the sky??
Yes, there will be some effect. Usually not too much, though.
It's much better (and easier) than trying to do it horizontally,
especially at low heights.
---
Chad Kurszewski, WE9V e-mail: WE9V@qth.com
The Official "Sultans of Shwing" Web Site: http://www.QTH.com/sos
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