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Reviews Categories | Antenna Rotators & Accessories | Channel Master 9521A Help

Reviews Summary for Channel Master 9521A
Channel Master 9521A Reviews: 11 Average rating: 3.6/5 MSRP: $$79.95
Description: Low cost, reliable rotor with digital display remote control. #9537 is an upgrade package to give existing older rotors full digital/remote capabilities. ($49.95)
Product is in production.
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KA4KOE Rating: 5/5 Apr 7, 2014 17:32 Send this review to a friend
Like it  Time owned: more than 12 months
You cannot use this rotor with a large aerial. You must also get the TB105 thrust bearing kit. With that, the rotor is good for 2 SF. I have had a KMA50500 LPDA on it over 5 years with nary an issue.
KD6RF Rating: 0/5 Oct 18, 2013 16:15 Send this review to a friend
2 units in 2 months dead dead dead :(  Time owned: 3 to 6 months
First unit (a gift from a friend) was in service for about 2 months then quit with antenna (4el 2 M yagi and small VTenn vivaldi) pointing due North.

I knew I should have taken it apart to see what was wrong, but instead I purchased a second unit thinking that it was a fluke failure.

3 days later the new unit failed in the same fashion – stuck due North.

I dissembled both units and found the same problem with both.

The unit doesn’t have an internal sensor that tells the controller where it is pointed; instead it guesses (Number of 60Hz cycles? Amount of time on?) at the position and displays it's guess on the degrees indicator.

Periodically, you must “re-sync”. The “re-sync” procedure runs the rotator to due North (and past if necessary). At some point near (or even past) it thinks due North is, a steel pin on the main drive gear hits a steel peg on a secondary drive gear and prevents further rotation, stalling the motor, with the now zeroed degrees display.

It’s fun to watch the pin fly past and miss the peg at everywhere but due North as this thing rotates around. The “North-ing” mechanism is actually pretty darn clever.

Unfortunately, it is also mechanically unsound. The end-mount bearings on the gears, or perhaps the shafts themselves, bend enough such that the gears start trying to tear themselves free from their mounts, and finally bind up solid.

A whack with a hammer will free them up, but of course they bind up again the next time or 2 that the unit “hits the peg” at due north.

Nice idea, nice controller and display, but a Big Fat Zero for the mechanism.
PD0MRD Rating: 4/5 Feb 12, 2011 05:29 Send this review to a friend
not bad at all.  Time owned: 6 to 12 months
Last year, i got one for free, including the old rotating controller.
I has one 2x10 el. crossyagi (2 mtr.) on it, and it performs very well.
When i got it, it was already some 20 years old, so first i cleaned the inside with white spirit, then lubricated it with sprayable chaingrease. Runs smooth now, even at -10 C.
SWMAN Rating: 0/5 Jan 14, 2011 16:06 Send this review to a friend
No Good ! Junk !  Time owned: 0 to 3 months
I just bought one of these rotors last week brand new. Took it home and connected it up on the bench to test it before installation. It worked on the bench for 1 minute or so them just stopped dead just sitting there humming. I checked everything per skimpy munual wiring, with remote and at front panel, did a full reset several times still just a loud hum.I called Channel Master 6 times in the past 10 days and can never talk to a tech for troubleshooting.Everytime the person answering the phone said they will call back within 2 days. Never a call back even after my 6 calls. Also they will not let you talk to a tech at the time. I don't think that they even have a tech. I took the thing back to Frys for a full refund. Save your money and buy something good and from someone who cares about their coustmers. 73 Jim
KC0UUT Rating: 4/5 Jan 27, 2009 14:52 Send this review to a friend
Good value  Time owned: 6 to 12 months
Purchased it from Menards home improvement store under the Philips brand in fall 2008.

Am using it to rotate a two element yagi (Mosley Mini 32A which has 16 foot wide elements).

Pros - it works, it's cheap, controller can be programmed to just punch a button and it will swing to at certain direction and stop.

Cons - It's cheap. The controller shows the angle that the antenna is pointing based on a guess of how long it takes the rotor to swing (no separate direction sensor is mounted in the rotor). Amazingly, this scheme to indicate direction works pretty well. It does lose track of the direction periodically (cold weather & strong wind affects this). Recalibrating the direction takes only a push of a button and about 1 minute, so it's only a minor nuisance. During the summer, it would hold direction for several weeks before needing recalibrating.

Cold weather does impact it. Last weekend it would not rotate when the temperature was below zero. Today it warmed up to 5 above and it came back to life. Apparently the little universal motor does not have the power to overcome the stiff grease when it is cold.
KG6POG Rating: 5/5 Jun 18, 2008 03:14 Send this review to a friend
Great 6 meter beam rotator  Time owned: more than 12 months
Perfect with the 9537 for anything up to about 10 to a max of 15 pounds.

I know people who have used this set up for their MA5B for years without problems, but I think that's pushing it, and I would rather not have to replace the rotator once everything's up and in place.

What I believe this unit is perfect for is anything up to a small 12 meter beam. It's perfect for a four to six element 6 meter beam that normally weigh in at under 15 lbs.

I have a small Diamond 502HB antenna set up with this system and plan to put a four or five element 6 meter beam up before too long.

I like the digital display and the remote control is great, but it takes way too long to turn the antenna 360 degrees. 180 degrees is bad enough, but the way the units set up there is no over play so if your pointed north east and hear a station in the north west, you sometimes have to hope the signals still there when the antenna gets pointed in the right direction.

But with all the positives and the price, I have to say its a great buy.
K3JVB Rating: 5/5 Jul 7, 2006 11:51 Send this review to a friend
gets the job done  Time owned: more than 12 months
Using it for a 5 band hex beam at 40 feet. Been through one average winter. Does need to be reset once in a while. As wind will move it slightly. Will spin the 18 foot, 20 pound hex 360 degres in about a minute...
The digital controller is small and out of the way. Easy to use , with the remote. Good value for a lite wind loading beam.
WD9IDV Rating: 2/5 May 11, 2004 13:00 Send this review to a friend
Not for windy installs...  Time owned: 6 to 12 months
Nice remote and display box.
However, Had it installed with a
Cushcraft MA5B. Rotor stripped
gears in less than 6 months up.
I am in a rather windy Chicago area

Thought I would try one for the minibeam, but it
was not built for that wind load.
Good rotor for 2m beams or TV antennas.

W1WIU Rating: 5/5 Sep 15, 2003 22:15 Send this review to a friend
Added the digital controller  Time owned: 0 to 3 months
I've had the rotor on a US Towers MA 40 for 12 months and added the 9537 digital controler 1 month ago.
The antenna is the Cushcraft MA5B mounted at 50'. The rotor is not on a platform or any mounting fixture.
The controler works great ! Easy to install, large digital read out, and it turns the antenna faster that the "push and wish" manual controller did. It is also a lot smaller that the old unit. The remote control that comes with the 9537 has the ability to "program" headings so you can swing the beam without having to hold any buttons down
I orderd the controller on line from Warren Electronics. Fast delivery, excellent price, and good feed back as to order status.
So far , it looks like a hard to beat combo.
KI6LO Rating: 5/5 Sep 15, 2003 18:17 Send this review to a friend
Light Duty Workhorse  Time owned: 6 to 12 months
First let me say that I made this little rotor due full duty as I was using it as the AZ rotor for a 2M/440 satellite setup holding a Cushcraft 144-20T 10x10 'Twist', a Gulf Alpha Antenna's 70cm 8x8 satellite yagi and a U110 (Elev rotor) and 7' crossboom. It didn't have a bit of trouble swinging the mass or holding it in high winds we have in the Mojave desert.

I agree that the digital readout is nice however there still isn't any feedback so I occaasionally would visually verify the alignment. I'm not sure what the actual windload rating is on this rotor but I had about 4 to 5 sq.ft. on it and it was mounted inside a light tower with just a thrust sleeve (no bearings) to turn against. All in all, well worth the money. It's down now but is already planning a new home for a 6m/2m/440 setup using this one.
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