[bobsgarage]

I read a lot of reviews before I ordered my CM9521A. They were all over the place. Some had no issues, some said theirs never worked right from the start. I figured most of the issues were due to installer error. Not so it seems.

Actually, I bought two because I was setting up a new antenna system and my other array has an old Radio Shack (noisy box) rotator that has lost it range over the last 15 years. Also, the Channel Master 9521A has a remote, which I really wanted. Another thing, all the competitors don't market rotators anymore, so there is truly a lack of choice.

I bought 1 CM 9521A through Amazon, the price was right, I thought. I bought the other through Solid Signal a week earlier as it was on Sale with free shipping. I bought it in April 2016 and now by early December, I am already experiencing problems. Aside from losing it's calibration, it had lost it's it range and only rotates approx 270 out of a possible 360 degrees, when it rotates.

So, in the early days of a very cold winter, I was back up on my roof. I loosened the clamps and climbed back down the ladder, hit the remote control aiming through a window and remarkably, it began working. It still had only partial rotation but I was happy enough to get off the cold roof so I tightend the clamps and it worked a few times and stopped again. WTF? Oh well. I expected it wouldn't be that easy...

Having another hour of sunlight, I went back up the ladder and brought my other new CM9521A that I hadn't mounted yet- yay! My fingers were numb even though I had gloves on, I had to remove them for the little 1/4-20 mounting nuts. I replaced the whole CM9521A rotator and I now have a functioning full sweep rotator again. I plan to work it hard and get my warranty out of it. Thankfully, the fresh one worked.

Now some of you already know what I have, a very tall 21' 1 3/8" SS-20 chain link top rail reinforced with 1" SCH 40 galvanized water pipe internally for the antenna mast so, it is fairly heavy mast. Add to that, an AD 91 XG and a MCM 30-2476 antenna and it is unwieldy.

However, knowing that, I fabricated 2 support bearings that support that weight. Yes, they actually hold ALL the weight, so that the rotator only has to turn the mast, a much easier task with no weight pushing down on the rotator motor. There is actually a 3/16" gap between the rotator and the base of the mast.



This support system is so effective, I can change the rotator without moving the antenna mast-at all. I loosened the upper clamps , removed the lower clamps, slide it a few inches down the main mast, unplug the three wires and (quickly) install the new one, clamping to the main mast as fast as possible.

That is why I decided that replacing the rotator as cold as it was out, because the thrust bearings were not just like another set of hands, but really like two hands. These are industrial bearings that are meant to support thousands of pounds rotating at hundreds of RPMs if not more.

I plan to send the 9521A back in Monday after I contact Channel Master. I am shocked that it could not even make it a year.

I'll possibly change my Amazon rating depending on how Channel Master handles this.

From what I understand, Channel Master is no longer manufactured in the US, it is a Chinese manufacturer distributor. They may be US owned but really just a marketer for Chinese manufacturing.

My old Radio Shack rotator is 15 years old and it still working.

I did some searches, and it appears that without getting into the bigger HAM radio stuff, which can be very costly, are there any recommendations?

Thanks, Bob