: Rotors for OTA: Channel Master, Nexxtech/Archer, Yaesu, Hy-Gain, Others
What is the maximum "OD" tube/pipe that Channelmaster's CM 9521A will mount to? And what size OD will the TB-105 thrust bearing accomodate?
2009-09-06, 10:34 PM
IIRC the common CM rotor can take up to a maximum of 2" OD size pipe/mast.
The TB-105 can only accept 1.5" size pipe. Even then many who use that support bearing must resort to filing down the metal on the inside of the bearing so the pipe to fit properly. I have one, though I find mine to be quite cheaply made. I have found that there a little too much 'play' in the bearings and the mast can move from side to side a little bit.
2009-10-16, 09:53 PM
I just bought a CM 9521A and I'm going to put it up tomorrow. Does anyone know which side of it is South? Having read the thread it appears that I should have the 4221HD facing south. Out of the box, there is an arrow pointing down (from the part that rotates) to the motor housing side with the Mast brackets. Is that the "south side"? The directions don't say.
OOPS!! Never mind! It is oriented south out of the box. Have to say that it works great in the basement...can't wait to get it on the pole!!
2009-10-17, 04:33 AM
Anybody know where to pick up a thrust bearing in the style that 300ohm posted a picture of?
2009-10-17, 07:14 PM
I just picked up an Archer ServoRotor II from the mid 60's, new in Box.
It seems to be a Cornell Dubilier Electronics (CDE) AR-40.
Here are some pics...
2009-10-17, 09:53 PM
That is an AR-40; Archer apparently resold it under their brand as well. Good buy!
2009-11-07, 05:11 PM
At a local store,
I came across a 9510 Channel master (rotor control box).
Assuming that it works. Is it worth picking up? (BTW, its $1.99)
Can i combine it with other rotors?
Read ya l8r,
2009-11-07, 08:31 PM
Thats a good price. Even if it doesn't work properly there may be some parts on the inside that can be used to repair another box. The AC output on that one would likely work on any CM rotor. That box is just 100% manual version compared to the other newer remote control ones.
I have a 9510a (30V 1A output) manual box and it's had problems inside where the AC contacts touch when the dial is turned. If you 'fine tune' a lot there is some arcing that happens and the little plastic part that holds the contacts in line starts to melt out of shape. It can quickly get to the point where the contacts are barely touching when the box is operated. By this point the resistance can be so high the small plastic part has no chance with all the heat created and totally melts to where there is no more contact at all, and the box no longer functions. Channel Master had a poor contact strip design with that box IMO. Not sure if others like it had the same problem.
2009-11-07, 09:59 PM
For $2, why not? ;)
2009-11-09, 12:56 PM
So for spare parts its a steal. Even if it doesnt work.
Read ya l8r,
2009-11-17, 06:14 PM
Still looking for an Alliance type Thrust Bearing, if anybody has a line on one.
Can anyone tell me if this CM rotor is any good, for what, what model, and how old...thanks
2009-11-22, 01:01 PM
I have that similar model . I bought mine maybe 15 years ago.It works great. What I did for a thrust bearing was go to TSC farm supply and got their thrustbearing and mounted that to the top of my tower. Greased it up good and works fine.
2009-11-22, 01:43 PM
Still looking for an Alliance type Thrust BearingUnfortunately if you cannot find one online through Norm's Rotor Service then you might have to take the photo to a machine shop with some measurements and have either a replica or a replacement design fabricated.
2009-11-24, 12:36 PM
Nice find, EscapeVelocity!
Mine is pretty close to yours, only a CPE (now Hy Gain) branded AR30.
It was inherited from a HAM friend ..but the rotor itself was in pieces. I cleaned it up inside and out and reassembled it as best I could determine.
Both units look good and the rotor does now turn in either direction but with one annoying problem : I can't seem to make the activation button on the controller "latch" -- it has to be held down constantly for the rotor to move to any dial selection.
What I would like to know is how the system actually works together so I can get a fix in place.
I have the circuit drawing but can't seem to figure out how the latching takes place.
How does the feed back circuit work and will it affect the latching circuit as part of the dial/switch combo?
And if so, what is the procedure for properly setting up the rotor?
2009-11-24, 12:47 PM
CM made an identical model for RS years ago. I believe it's a 15-1225A and the docs can be found at the RS site:
I found the biggest problem with the unit was the main drive gear. It's made of a "soft" plastic that over time gets brittle and strips out. You may want to open the case and check the gear for wear. Finding a replacement is a rather futile exercise -- garage sales not withstanding :rolleyes:
the guy who gave me the rotor dropped it right before handing it to me, and one of the 4 bolts attached thru the housing sheared off even with the housing.
I tried using a biting tool to grab what was left of the bolt and unthread it from the housing. Then I gave up.
Next I tried drilling out the remainder of the bolt, and after 2 hours, I was barely able to make a dent in it, but easily damaged the housing!
I used a Titanium drill bit and it did nothing. Does anyone know how to get a hole drilled thru the housing and thru the bolt? (I imagine it will take a drill press with the hardest possible drill bit)
2009-11-25, 11:17 PM
I can't really visualize what bolt broke, but in the past I have had good success removing broken bolts by welding a washer onto what remains, then welding a nut onto the washer, and turning it out. A quick squirt of some lubricant while it's hot will sometimes help to loosen it.
After you've attempted to drill it out, there might not be enough left to weld onto.
2009-12-01, 03:50 PM
The quickest fix is to get a bigger u bolt and place it around the entire rotor bolting it to the post you've got .
Or some version of that
I drilled thru the casing and placed 2 new carriage bolt-studs from the inside of the casing with a nut on the outside, it worked out great, better than the original!
This way the original U-bolts, which are specific to the rotor (believe me I searched everywhere for them), can be used as designed.