Anyone Tried a Rotor for an 800mhz Yagi from one of the cheap TV Antennas?

thinbluebbq

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WB9YBM

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Any antenna with a wind-load and mass equal or less than a television antenna should be okay to use with a TV antenna rotor. (Unless someone out there knows of any other considerations that I'm missing?)
 

jonwienke

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As long as weight and wind load are within the rotor's specs (taking mast height above the rotor into account), you're fine. An 800MHz yagi is smaller than most TV antennas.
 

dispatch235

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Any lightweight tv rotor should handle a 800mhz beam with ease... I have ran them with some very large tv antennas and FM Stereo antennas with no problems
 

thinbluebbq

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As long as weight and wind load are within the rotor's specs (taking mast height above the rotor into account), you're fine. An 800MHz yagi is smaller than most TV antennas.
The only challenge with what you said and the link I posted is that the rotors don’t have specs listed. They are part of these cheap antennas so there isn’t any specific info but I figured they can turn those antenna so they should be able to turn an 800mhz yagi
 

jonwienke

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If the antenna is smaller and lighter than the original, you're fine.
 

Ubbe

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If you manage to balance the wind load, so that it is the same wind drag on both sides of the axis of the rotor, then even the weakest motor can turn an antenna as there will be no load if the wind blows equal much on both front and back part of the antenna. But most antennas have their fittings at the end of the antenna and not in the middle of the boom lenght. But then one could extend the antenna at the back in the other direction of the motors axel using a square alu tube or something and screw a vertical metal plate on it and adjust its size or position to equal the antennas wind load. Real expensive rotors have breaks to stop the wind from turning the rotor but cheap ones lack that. They usually also have no way to show the direction, you just activate left or right turn until you get the best signal.

/Ubbe
 

LS101

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I see those type of antennas and rotors all the time at the flea markets from around 20.00 bucks, neighbor had one spun like a pin wheel until it broke, plastic gears are no thicker than a piece of paper. You pay a little more for the one i mentioned but they last, One has been up about 10 years now, the other one i have a camera mounted to it, cheaper than buying a PTZ camera.
 

Ubbe

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I saw this posted yesterday on FB.
I have a similar that where half that price but looks very similar so I had to buy it at that low price. I used it to monitor wireless phones in the 960MHz band and it had a pre-amplifer as well that actually worked. It came with 30ft RG58 so the amplifier was necessary.

It was a single button device. You pushed the button and it would turn in one direction. When you pushed it the next time it turned the other direction. You had no clue of where it actually pointed. You had to turn it when you had a signal to try and get the best signal possible when activating the button. The problem was that it sometimes continued in the same direction two or three times in a row.

/Ubbe
 

DJ11DLN

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If that's like the one I helped a friend put up, and it looks identical, the rotor is part of the assembly. You'll have to take it apart and try to fabricate a way to mount your yagi. And hope that you didn't compromise the weatherproofing (sic) of the unit in the process. And you wouldn't have a traditional rotor control, just IIRC a remote with a button for CW and one for CCW. You would have to go out and look at it to see which way it was pointing.

I'm not trying to rain on your parade here, "Tightwad" is my middle name too, but I'd just get a real rotor and be done with it. Much less of a headache factor.

P.S. The antenna we put up was a little better than the rabbit ears he had been using before...but not much.
 

krokus

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If that's like the one I helped a friend put up, and it looks identical, the rotor is part of the assembly. You'll have to take it apart and try to fabricate a way to mount your yagi.
I was just about to point this out. Unless you want the challenge, it would be far less hassle & cost to buy a rotor, especially if you find a used one.
 

WB9YBM

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If you manage to balance the wind load, so that it is the same wind drag on both sides of the axis of the rotor, then even the weakest motor can turn an antenna as there will be no load if the wind blows equal much on both front and back part of the antenna. But most antennas have their fittings at the end of the antenna and not in the middle of the boom lenght. But then one could extend the antenna at the back in the other direction of the motors axel using a square alu tube or something and screw a vertical metal plate on it and adjust its size or position to equal the antennas wind load. Real expensive rotors have breaks to stop the wind from turning the rotor but cheap ones lack that. They usually also have no way to show the direction, you just activate left or right turn until you get the best signal.

/Ubbe
There's also the mass to consider--a higher mass (heavier antenna) will require more torque to overcome the moment of inertia to get it moving, then you've got the same situation in reverse when trying to stop the antenna motion when it's been turned in the direction you want it to go in. And even when the antenna's not moving we've got to consider holding capabilities when the antenna's being held in one position in windy circumstances.
 
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