[TowerTalk] Ring Rotor problem ?

k2we@juno.com k2we@juno.com
Wed, 18 Nov 1998 18:20:11 +0700

I've been having a strange problem with my ring rotor. It's mounted on
the top of the 3rd section of my Tri-ex LM-470D  70' motorized tower.
It's worked fine for the past 5 years. In the past 3 months, I've torn
the coax 4 times, going to the antenna mounted on the ring rotor (it's a
Force 12 4BA 12 element yagi for 10/12/15/17 meters). It happened again
last week. This time I said I've had it... Since I'm in the alarm
business, I installed a CCTV camera looking at my tower. I can now see
the entire 4BA as well as the Magnum 520/340 mounted on top of the tower.

I went to turn the ring rotor and discovered it turned well over 360
degrees.. In fact it almost went around twice before I realized what was
happening and stopped it. Now I see why I ripped the coax. 

Question 1:  Can someone tell me why this is happening?? Are there limit
switches in that motor housing on the ring rotor??  I've had it open to
replace the indicator pot last year. I was suprised to find they use a
windshield wiper motor to do the turning...It worked fine after the

Question 2: Can I purchase a new motor assembly?? Has anyone ever had to
replace this assembly before?
I'm afraid to ask... if you did, how much was it???

By the way, I used a camera with an auto-iris lens. This allows me to see
the antennas in total darkness!! I think it's a good investment. I don't
know why I didn't do this years ago.... I know I have well over $8,000
invested in my antennas.. For another $475, I'm now able to watch the who
set-up when it's turning... really neat...

I was curious how bad I would wipe out the camera when I run the legal
limit... I installed 2 chokes in the camera housing. I just cause some
very minor lines on the monitor... Not too bad...

Look forward to any comments...

73.. Steve/K2WE  Dobbs Ferry, New York.

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