I am using a mobile crank-up / tilt tower for some antenna testing that has a
top section too small to get a ham4 rotor in. Unfortunately that means I need
to mount the rotor on a pole that extends from the top of the tower.
The good thing about this setup is the tower nests and the tilts down
essentially parallel to the ground, allowing you to mount the antenna while
standing on the ground. The bad thing about that setup is the rotor has got to
be stout enough to hold the antenna weight while the rotor is temporarily
horizontal.
I have used a ham4 in the past but that was with antennas which were pretty
light weight (under 75 lbs). This time the antennas will be somewhat more
heavy – up to about 200 lbs – and I have a tailtwister available.
Would the tailtwister would be happy holding that much weight off the nose when
it’s temporarily horizontal?
Higain says the load capacity for a mast mounted configuration is half of a
inside-tower-mount case but I have no idea if that is applicable in the case of
the rotor being mounted horizontally. Seems like it would because the rotor is
going to feel a lot of torque in the externally mounted case with serious wind.
In my case wind is not an issue. I don’t leave the antenna on the tower when
I’m not testing it. So the only question is how the tailtwister would do with
a couple hundred pounds pulling down on the top when the tower is tilted over?
Appreciate any comments or insights.
73/jeff/ac0c
www.ac0c.com
alpha-charlie-zero-charlie
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