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Ultra, I suggest grabbing a coffee (or your drink of choice), and reading through this thread. Lots of excellent info here.

What is your budget?
 

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G225, I assume that you've checked that the control box is getting power, etc? How is your rotor mounted? (i.e. top of tower with or without a thrust bearing?).
 

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G225 - What model of Channel Master Rotor? Controller? how old is it? New one?

Testing will depend on type of CM rotor you have.

Voltage and current can probably be read off Adaptor that comes with / powers controller - if your CM rotor is anything like what I have.

[ I think my adaptor / for my model was 18 V AC - and I believe that is what is fed up to rotor up 3 wires. Current is limited to something "safe" by the adaptor, I would say ]

If I assume rotor is mounted, and currently in use high up - then check connections first down at controller.

You could also put a volt meter on controller outputs to rotor - and check that voltage is being supplied - when controller is trying to turn rotor. That's a simple test. And you could measure and confirm voltage output at that time as well.

But if you determine the problem is up at the rotor - and not simple to solve - (check connections and voltage up top at rotor too first) ... then I would take it down and set it up and test it on the bench.

Wires up to rotor ? Are they good ? Visual check / Voltage check at top will help find out.

Connections at rotor and controller end? - mine were on spring clips that look like speaker connections. Same thing at the controller end. Check those too.

Not easy - may have to climb and disassemble setup - mast / rotor / antenna - take it down and test it on the bench.

Some of these newer CM rotors have mechanical and electrical issues/problems. We have learned. Must read back in this thread to see details.

Be very careful if you climb. But try to do basic tests on ground first - before climbing.

( I don't know if you can do any sort of "resistance" test, on the wires at the controller, on the leads going up to the rotor, to see if you can check and confirm continuity / good connection and try to see if you can see / measure the proper motor winding resistances on the cable and connections that go to the rotor.. Don't mix up the leads. Mark them 1. 2. 3. before you disconnect to test - or write down / remember current wire colors / correct connections. )

When these CM rotors fail - they are a pain in the ...
 

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Sorry for my English and thank for help me.

Ok, I have motor in my first house and the seal is broken.

Connected directly on controler, the motor don't turn but it try but it is blocked probably because water enter.

My controler is in my second house. Professional install my second motor with my new DB8.

This is identical: http://wd4eui.com/Pictures/TV_rotor.jpg

I have not controler here, I search how to test for repair or go to recycle.

Adaptor 18 volt ?
 

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Thanks for picture. (Anyone know what CM Model numbers are? Rotor? Controller?)

I do not know correct voltage output for this type of CM Rotor Controller.
( so I would *NOT* try to apply any voltage to wires going up to the rotor )

My controller is different than this one - so you can not assume the same voltage.

The type of CM ROTOR you have now - at new house - must have the correct model/type of CM controller - to run it correctly.
There are different types and models - and different methods of "control" - and different voltages - and different wiring methods too.

[ So - The rotor / controller pair must MATCH . ]

So - must go get original / correct controller from old house - or one exactly the same.

Hook it up correctly - and try to see if the rotor will work that way.

Sorry - no easy answer for this.

Get correct controller for rotor you have at this new house. And try.

Do not assume "problem" with water in rotor, or whatever - YET. Just hook up correct controller and see what happens.

When you have proper controller again - ask for advice of your "professional installer" again - if you need help - to connect and test rotor properly.
[ or to attempt to troubleshoot it, or make it work or fix it - unless you feel comfortable and knowledgeable enough to do this yourself. ]

best of luck - tell us how it goes.

[ it may help to figure out, or know your exact model number - of CM Rotor and Controller.
Then you may be able to search and find other information online about this rotor and controller.
i.e. like user manual / specs etc.]

So I ask again:

CM Model number ? Rotor___ Controller ___

How many wires go up to Rotor ?

[ if it is impossible to get original controller back from old house - then maybe an online search to find / order / buy / and have shipped to you - a correct used replacement controller online ]

? Call / Contact person now at old house - get them to ship you old controller. Tell you what model numbers are written on bottom.

You need correct controller. I am fairly certain.

[ You will need it anyway - for everyday practical use of this rotor - in any case.]
 

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Ultra, I suggest grabbing a coffee (or your drink of choice), and reading through this thread. Lots of excellent info here.
It could take me longer to do that, than to acquire a taste for coffee. I was hoping that some article digested all that.

What is your budget?
I don't really have one--I just want to save money (bet no one in the OTA racket ever said that before!) Even if I spent 1000$ (I've already got the antenna for free) then in a year, I'd start saving money over the sat costs I've saved (albeit, w/less content). But what I'm really trying to do right now is not spend money unnecessarily.
 

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I am looking for current opinions or experience on rotor choice. I will be installing a DB4e on a 1-1/2" x 20' aluminum mast using a chimney mount.

The Eagle Aspen single cable off air antenna rotator model ROTR100 and Channel Master CM 9521A Antenna Rotator system are available thru S&R. Are there any technical reasons why i should prefer one over the other? Then there is the Hy-Gain AR-500 and others.

Here's my TVFool report: TV Fool
 

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If you did find an eagle aspen, let me know. I would buy another:)
But I don't think you will. As they are no longer in production, or distribution. I think Eagle-Aspen either was bought by someone else,
or they just changed their focus to strictly Pizza size satellite dishes & accessories:(

I wouldn't recommend a new channel master rotor anywhere north of the land of Dixie. Too many horror stories.
 

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How about this one compared to the CM 9521A? ...

RCA VH126N Antenna Auto Rotator with Remote

I have another question about installing the rotor. My plan is to install it near the top of the mast so that there is a smaller load for the rotor to actually rotate. A friend suggests quite seriously to mount it near the bottom for easy access, and that having the rotor rotate the 15+ feet of mast about it plus the antenna will not be a problem.

What do you think of this?
 

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I really can't say about the RCA rotor, having no experience with it. But I can't imagine another being as bad as the newer CM in our cold weather.
But, like I say, what do I know? Pretty much anything made in China is gonna be suspect until proven otherwise. If ya want reliability over cost, get a 2nd hand Hygain. Forum member Jase88 (Kitchener) was selling one recently in the "For Sale Forum", local pickup. Not sure if he still has it though?

I think you wanna keep in mind stability, meaning not to make it top heavy in the wind?? Mine is chimney mounted, with a short section of mast fixed to the chimney mount. The rotor bolts on to that, probably around my chest level (short guy here...). Then the mast for the antennas, nuther short section plops in to the Rotor.

Your tvfool says 40 feet. Are you installing a tower? If so there's other considerations I am sure, which could be found in the tower rigging thread.. Check this this thread for earlier more helpful posts... search for Jase88's posts in particular.
 

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mdawdy: A rotator can't support a 15' mast with antenna. Even HAM-oriented rotators don't recommend supporting more than 2.5-3' of mast plus antenna without a thrust bearing.
 

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Thank you, that is what i thought. I asked because my friend has been known to be right the odd time :) I'll be doing a normal, intelligent-guy install up top near the antenna, like the instructions usually say.

The TVFool says 40' because i have a 1-1/2" OD x 20' aluminum mast attached to the chimney. I am replacing this setup with a rotor and a Antennas Direct DB4e ...

 

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CM 9251 maximum mast length

I will be mounting a db8e (top antenna) and an Antennacraft y5 7-13 on the same mast controlled by a CM 9251 rotor. The CM user's manual states that 3 1/2 feet is the maximum length. Optimum spacing between the two antennas is 36 inches ( half the wavelength of channel 7), however this would make the mast 60 inches, 18 inches longer than the maximum recommended length

The two antennas weigh just over 16 lbs. There is no wind load published for either antenna but some have guessed that the db8e is about 3 sq ft and I would guess that the 5 ft long y5 7-13 has a minimal wind load.

Need some opinions: Are the combined wind loads of my two antennas small enough to exceed the CM recommended maximum mast length?
OR Is a 5 ft mast too much of a load?

My next option would be to reduce the length of the mast by 16 inches ( 1/4 wavelength of channel 7) which would be only two inches over the 42 inch maximum.
 

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I would keep to the recommended mast length, or close. I would put the VHF on top, with the db8e below to reduce the stress of its windload on the rotor, unless you are trying for some very weak UHF signals.

holl_ands has modelled the effect of two antennas being separated by less than the rule-of-thumb distance, and he didn't find a significant impact on gain or polar response, only on F/B (or was it F/R?) ratio. Be aware that those rotors don't have a brake, so strong winds may rotate it. You calibration will then be off (even without wind, they should be recalibrated frequently if accurate pointing is important).
 

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DXer,

You might also consider something like an NTE TB-105 Thrust Support Bearing to add additional structural integrity to long masts with your TV Antenna Rotator.

I have an NTE U-106 rotor (similar to the Channel Master) and turn a Y 10 7-13, two HDB8X’s and a Winegard 10 element FM antenna. This doesn’t solve the lack of a break and the occasional wind-load turning but mine has been up for several years and is capable of turning my array. The thrust bearing supports all the weight of the array/mast combination and relieves a lot of side loading torque from the rotor.
 

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Pete, it's actually chinadog who is asking the question.

With regard to the NTE TB-105 thrust bearing, I went to order one of these earlier this year, only to find they are no longer available new. I searched and searched, and eventually got hold of a well-used one. It seems like the usual story - the availability of OTA equipment grows ever smaller.

It is not difficult, however, to make a thrust bearing with a sleeve of ABS, PVC or metal piping sized to fit over the mast, and grease applied between the mast and piping. I used that approach successfully for 14 years until I decided to 'upgrade'.

For several years, I had a 91XG on a small rotator comparable to the Channel Master (the Eagle-Aspen DiSEqC rotor), with the pipe thrust bearing. I replaced the 91XG with a 'monster' CM3671 antenna. The rotor failed after a few months - due, I assumed, to the increased wind loading. I upgraded to a Hy-Gain Ham-4 rotor with the NTE TB-105 thrust bearing, and all's well so far.

I also have other three-wire rotors, and bench testing shows how quickly they get out of synchronization. Merely starting and stopping them several times in a full rotation puts them out significantly. Either the DiSEqC control (of the now-unavailable Eagle-Aspen rotor) or the potentiometer feedback of the ham rotors is necessary for accurate and repeatable pointing. Otherwise, one is obliged to run the rotor to end-of-travel each time to re-calibrate it if accurate pointing is desired.
 

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Hi rabbit73, long time!

Sorry guy’s, I didn’t know I was sending you on a wild goose chase?

I’ve had one TB-105 for years and ordered another one from Wiley’s Electronics in San Diego, CA when I was setting up my antennas. I just checked their site and they no longer list them.

I have one Alliance-HD-73 Rotor, 3 really old 5-Wire rotors and the NTE ECG U-106 3-Wire rotor. The only reason I use the NTE ECG U-106 is because I couldn’t in good conscience sell (or give) it to anybody else. Fortunately, I use separate antenna arrays to point @ San Diego & LA so once I position my array’s they remain stationary. Of course the 5-Wire San Diego array never moves and I only have to “correct” the LA array when we have high winds. I think it’s criminal that manufactures even sell this poorly engineered design –especially to home users.
 

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For several years, I had a 91XG on a small rotator comparable to the Channel Master (the Eagle-Aspen DiSEqC rotor), with the pipe thrust bearing. I replaced the 91XG with a 'monster' CM3671 antenna. The rotor failed after a few months - due, I assumed, to the increased wind loading. I upgraded to a Hy-Gain Ham-4 rotor with the NTE TB-105 thrust bearing, and all's well so far.
Hi DXer, wouldn't happen to still have the broken eagle aspen kicking around and be willing to 'donate' to a guy for cost of shipping of course, to use for diseqc projects would ya?
 
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