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Discussion Starter · #1 ·
In my question to build an over-engineered HDTV reception system, I want to install an antenna rotor. I probably don't need it since 90% of the stations are located at the same location, Sutro tower. But I want to be able to get KICU and KNTV (for when it becomes an NBC affliate). I also just think a rotor is retro-cool! http://www.avsforum.com/ubb/smile.gif


Can I put a 10 foor mast into the rotor or will that torque the rotor too much when the wind blows? (i.e. should I only use a 5 foot mast in the rotor?) The antenna is a Channel Master 3018.


Any other general rotor advice?
 

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I use a 15 foot mast in one of my rotors. 10 ft should be no problem if you add a bit of support.


I have Channel Master Rotors, and use their optional bearing 3-4 feet up from the rotor, to minimize the rotor load.
 

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Discussion Starter · #3 ·
Quote:
Originally posted by jhe:
I use a 15 foot mast in one of my rotors. 10 ft should be no problem if you add a bit of support.

I have Channel Master Rotors, and use their optional bearing 3-4 feet up from the rotor, to minimize the rotor load.
How about without a bearing? I wouldn't mind adding the bearing but I don't think I can easily find one locally. At least I don't remember seeing one at Fry's yesterday, Home depot wont' have that, . . . perhaps RatShack with have a bearing?

 

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It would probably be OK if you used a heavy duty rotator, but not recommended. Your antenna is about 10' long, and would probably put quite a load on the rotator with the heavy winds you sometimes have in Palo Alto. I would recommend you put the rotator closer to the top of the mast with a short mast for the antenna, and put guy wires just below the rotator.


I really think in your case you would be better off to use a smaller UV antenna pointed toward SJO and a separate feedline to the second antenna input of your HDTV receiver. You have to run a line anyway (rotator or coax), and this way you would have instantenous switching instead of waiting 30 seconds or so for the rotator to come around.


Bob Smith
 

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Discussion Starter · #5 ·
Quote:
Originally posted by Bob Smith:
It would probably be OK if you used a heavy duty rotator, but not recommended. Your antenna is about 10' long, and would probably put quite a load on the rotator with the heavy winds you sometimes have in Palo Alto. I would recommend you put the rotator closer to the top of the mast with a short mast for the antenna, and put guy wires just below the rotator.
Yeah, I guess the 5' mast will have to do. I probably don't need the extra height anyway. I'll put the rotor on top of a 10' mast so I'll get 15 feet from my roof. That should put me over any power lines.

Quote:
Originally posted by Bob Smith:
I really think in your case you would be better off to use a smaller UV antenna pointed toward SJO and a separate feedline to the second antenna input of your HDTV receiver. You have to run a line anyway (rotator or coax), and this way you would have instantenous switching instead of waiting 30 seconds or so for the rotator to come around.
Well . . . . I don't think the terrestrial add-in for the model 6000 has 2 antenna inputs. http://www.avsforum.com/ubb/frown.gif That is another thing (besides the constantly running fan) that they should fix in their next attempt at a terrestrial receiver.

 

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I think the bearing you're referring to is a "thrust bearing". These usually reside in the top of a tower where the mast exits, allowing the rotator to be placed inside the tower where the moment caused by the length of the mast wouldn't be placed on the rotator bearings. I suppose one of these could be made with guy hooks, but that sounds like quite a kludge.


Bob Smith
 

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Discussion Starter · #7 ·
Quote:
Originally posted by Bob Smith:
I think the bearing you're referring to is a "thrust bearing". These usually reside in the top of a tower where the mast exits, allowing the rotator to be placed inside the tower where the moment caused by the length of the mast wouldn't be placed on the rotator bearings
Yeah, I think he was referring to the Model 9523 on this page:
http://www.channelmaster.com/pages/MC1and2.htm


But I don't need it. I'm just over-engineering my system. I probably don't need the rotator at all. I just think they are retro-cool.
 

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dagman,

Quote:
Originally posted by dagman:
Yeah, I think he was referring to the Model 9523 on this page:
The Model 9523 has been discontinued. Bummer

Quote:
I probably don't need the rotator at all. I just think they are retro-cool.
If you decide to get a rotor, consider the Channel Master Model 9521. Try Consumer Direct at: http://www.consumerdirectonline.com or
Stark Electronics at: http://starkelectronic.com


You can change the direction by entering the compass heading as a three digit number. Another method is to memorize the compass heading for each of your stations, then to change the heading for the desired station all you need to enter is the corresponding stations two digit number.


The IR system will emulate a couple of Pioneer products. This will allow most universal remotes to control your rotor. More info at: http://www.channelmaster.com or this one to go direct to 9521 info:
http://206.155.192.130/pages/rc1.htm


------------------

Wendell

Technical Services Supervisor

MAETV


[This message has been edited by Wendell R. Breland (edited 03-27-2001).]
 

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Discussion Starter · #9 ·
Quote:
Originally posted by Wendell R. Breland:
If you decide to get a rotor, consider the Channel Master Model 9521.
Yeah, that is the one I'm going to get. I'll probably just pick it up at the local Fry's Electronics. When I first cut off my cable TV service a year ago, there was not that many terrestrial antennas at Fry's to choose from. A year later, it seems like the terrestrial antenna supply has doubled. It seems like many antennas must being going up for HDTV in my town. Well . . . it could also be that AT&T took over the local cable TV plant. http://www.avsforum.com/ubb/wink.gif
 

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Wendell,


Sure enough,the alignment bearing is gone! Glad I bought two of them.


This coincides with what the guy who owns the local RS said today and that is CM is eliminating all high windload antennas and related accesories.


Maybe they're involved in some product liability issues-the instructions that come with most of their products are too vague and confusing for most do-it-yourselfers.


Also,as a hint for installation of these bearings,do not use mast material larger than 1-3/8" diameter.I learned the hard way and tried 1-5/8" for a stronger mast install,but the rotor would hang up because of binding(it strays from center rotation to an elliptical pattern,the way it's made).


[This message has been edited by MAX HD (edited 03-30-2001).]
 

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I have successfully been using the Channel Master rotor mounted on a 5 ft mast in a 15' ground mounted tripod, with a 10' 1 1/2" mast in the rotor to turn a full size VHF Quantum (139" dual boom) below a Radio Shack U120. Other than occasional overshoot during high winds, it has worked perfectly until I replaced the setup a couple weeks ago with a QUantum 1162 combo V/U antenna on a 3' tripod on the roof.


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SVR-2000 2.0 130 hrs

HDR-112 2.0 14 hrs

REplay 3020 20 hrs
 

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Davenlr:

How do you like the CM1162 performance. Have been seriously considering

that antenna for my application. I have one DTV in VHF band and one in UHF.

Also did you go with Quatum's pre-amp. The VHF DTV transmitter is 45 mi.

away everything else including analog is 20 mi. or closer. Did you

purchase from Stark or locally? Thanks alot. Have a great weekend.

GO MSU in HDTV!!!!

John


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JPH
 

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Hi dagman,


I have the remote controlled CM9521 and it works very well. I've got it programmed to rotate my CM4241 between the DC and Balto stations which are between 45 to 90 deg off.


Got it cheap from consumerdirect . They sell it for only $65 ($25 cheaper than stark).


Rotor definitely helps tons in enjoying OTA broadcast.


Thanks,

Errol


------------------
KeohiHDTV

Your Friendly HDTV Tips Site


[This message has been edited by kealii (edited 03-30-2001).]
 
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