Dennis W0JX wrote:
> I've had a TR-44 since the mid-60''s when they first came out. When I first
> put up my TH-6, the rotor lasted about two days before the cast ring gear
> broke. I replaced the rotor with a T2X Tailtwister.
>
When I first put the system up I put in a Ham V. It lasted until the
first wind, or like your 44, about 2 days.
The wind was about 30 MPH. I needed to reposition from the NNW
Australia and Japan from here, to NE for Europe. As soon as I released
the brake it was pointing NE and headed on around. I released the brake
and that was the end of the rotator. I was waiting for my PST-61 which
is a tad beefier. Had I not wanted to work Europe at the time it
probably would have held, but the brake dropping in shattered the whole
works. It also took out 4 pigtails by the time I could get up there and
secure things. I waited for the wind to go down as I was not going up
there in that wind with things flailing around.
It was about 2 days work for me working alone up there (I did have
ground help) lowering the mast 25 feet while sliding the antennas up and
cutting the pigtails loose, replacing the 144 and 44 pigtails, raising
the mast up to position the 7L C3i 6-meter yagi and taping the
aforementioned pigtails in place, then replacing the pigtail for the
6-meter antenna, and raising the mast yet again to position the
tribander while taping the 3 pigtails in place. Then replacing the
pigtail for the tribander and raising the mast another 2' while coiling
the pigtails on the tower top plate and connecting them to the runs down
the tower.
The Ham series and tail twister really don't use a brake. They use a
wedge which is a hard mechanical stop. Combined with some tiny spur
gears results in the motor adding little resistance to rotation. They
allow the antenna to coast to a stop, but this only works if it's not
windy of the wind favors stopping right where you want it. Otherwise all
of that inertia is transfered to the tower and guys (if you have them.)
when the wedge drops into place.
I much prefer the rotators that use a double worm gear drive even in the
range of the Ham V or Tail Twister. With a soft start and stop, plus the
resistance of the drive being enough to prevent rotation I think they
are far easier on the tower and antenna. Also the smaller ones with the
only a slightly higher rating than the Ham series are not all that much
more expensive.
73
Roger (K8RI)
>
> I also purchased a replacement forged steel ring gear for the TR-44 and use
> it for light VHF antennas. I would not use it for a triband beam of any size.
>
> 73, Dennis W0JX/8
>
>
>
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