NORM'S ROTOR SERVICE TM
1. What is the color code for the cable connecting my rotor and control box?
The colors vary from manufacturer to manufacturer. But it really doesn't make any difference, as long as you make sure that you're connecting terminal 1 on the rotor to terminal 1 on the control box, terminal 2 to terminal 2, and so on. Also, on the HAM series and T2X rotors, you need to be aware that the heavy wires must go to terminals 1 and 2. Norm uses this color code for CDE/Telex/Hy-gain rotors
1. black #18 gauge 2. white #18 gauge 3. green #22 gauge 4. blue #22 gauge
5. orange #22 gauge 6. yellow #22 gauge 7. brown #22 gauge 8. red #22 gauge
Norm uses the following color code for Alliance 6 wire rotors and controls.
1. black #18 gauge 2. green #22 gauge
3. blue, orange, yellow note: twist these 3 (22 ga.) together to make one heavier gauge wire on each end
4. brown #22 gauge 5. red #22 gauge 6. white #18 gauge
2. When I sent my rotor to you, it looked old and beat up. The one I got back looks brand new. Why did you send me a different rotor?
The rotor you got back is your rotor. We bead blast clean every rotor we service and install new hardware as required. When we send a rotor out the door, it looks and works like new. But, unless you were specifically exchanging your rotor for a new one or you participated in our exclusive exchange program, it's your rotor you got back!
3. What is the difference in the Ham series of rotors?
The Ham-M rotor was released in 1957, and there were 5 series with the last rotor being produced in 1973. The Ham-M rotor would have the series number, 1 - 5, followed by 3 digits which indicated the week and year of manufacture. For example, a rotor with the series number 5 322 would be a Ham-M, series 5, manufactured in the twenty-second week (the '22' in '322') of the year 1973 (the '3' in '322').
A Ham-M has a single-levered control box with a meter. In 1973 the mold for making the Ham-M control unit shell was destroyed in a fire. So rather than spend the money to replace the mold, the Ham-2 was born. The rotor was the same as the Ham-M, but the control unit was replaced with a three-button unit with a continuous meter reading.
In 1977 the Ham-3 rotor was released. The Ham-3 supported a new motor with an internal brake, as well as a brass motor gear. The brake wedge was redesigned, as was the brake housing, which gave the new unit a capacity for more wind surface area. The control unit for the Ham-3 supported a new PC-board-mounted meter.
In 1978 the Ham-4 or Ham-IV rotor was released. This rotor had a new steel ring gear and a reinforced upper mast support. The only changes to the control box were the addition of a new face plate, plastic top and bottom covers, and a new meter with reversible meter scales. Also in 1978 the Tailtwister rotor, commonly referred to as the "T2X," was introduced. The T2X is a Ham-4 with an even heavier upper mast support, a heavier brake wedge and brake housing, and 40 additional ball bearings. And the Tailtwister control unit has three LED's that the Ham-4 doesn't have.
4. What happened to CDE and Telex/HyGain?
The Cornell Dubilier Electronics company sold their rotor division to Telex/Hy-Gain in 1981.
Hy-Gain decided to support only the AR-22, AR-40, CD45-II, Ham-4, and Tailtwister rotors.
All rights to the other rotors were assigned to Norm's Rotor Service. Today we are the only
facility with parts for the original units. We have almost all parts for the AR-22, AR-33, AR-40,
AR-50, BT-1, TR-44, CD-44, Ham-M, Ham-2, and Ham-3 rotors. Telex/HyGain sold the HyGain line of rotors to MFJ in May of
1999 (Of course, we also
have parts for the rotors that Hy-Gain continues to support.).
5. What happened to the Alliance Manufacturing Company?
Alliance stopped production of their rotors in 1994. Norm's Rotor Service purchased their entire
parts inventory for the HD-73, U-100, and U-110 rotors and controls.
6. When I took down my rotor and sent it to you for repair, the top turned. Now that you've repaired it, I've tested it on my bench and the bottom turns instead. What gives?
Welcome to the wonderful world of physics. Rotors are a bit top-heavy. When you lay them on their sides, as you must to make the connections for a bench test, it's the top of the rotor which is in contact with the table. So the bottom moves inside the top. Trust me: if you bolt the bottom down, like it is when the rotor is installed in your tower, the top will still turn.
P.S. This really isn't a frequently asked question, but it has been asked, so we thought we should include it.
7. Is a brake delay really necessary on a Ham-series or Tailtwister rotor?
Yes, it really is good insurance. The brake delay prevents the rotor from being stopped too suddenly. The bigger your antenna is, the more inertia there is. The "drive train" (consisting of rotor, mast, antenna, bearings, and whatever else is up there turning) at the top of your tower can be a lot of mass. So when the antenna reaches the heading you're turning it to, the inertia makes it want to keep turning.
Every time the brake engages before the "drive train" has settled down and stopped turning and "whip lashing," there is an enormous strain placed on the brake and the brake housing. When this happens a few times, the brake assembly just plain eats itself.
At $35.00, a brake delay unit like the BD-189 is probably less than half the cost of the repair. And the repair isn't a matter of "if;" it's a matter of "when."
8. Which is better, the 51465 8 screw terminal board, the Amp plug, or the Cinch-Jones plug, directly wired to the rotor on my Ham-4 or T2X?
The Amp/Cinch plugs that Hy-Gain and CATS are supplying are okay, but they are not rated for the solenoid current.
In addition these must be totally waterproofed
to prevent water from getting into the connectors a shorting. They also make servicing of the rotor much
At Norm's Rotor Service we supply the same terminal board with stainless steel screws. These boards have survived very well for years with little or no corrosion.
This is Norm's recommendation and is available as part number 51465S. However, we can also supply the Amp and Cinch-Jones plugs.
9. What type of grease should I use in my rotor?
We recommend either a white lithium or green emerald. Under no circumstances should wheel
bearing grease or any other grease with fibrous material content be used.
10. I am thinking of purchasing a rotor, but don't know what kind to purchase. What suggestions can you offer?
We strongly favor the American brands. Before buying a rotor made outside the U.S., find out
from the dealer or manufacturer what the availability of parts and service will be.
Also talk to
someone who owns one. We constantly hear horror stories from people who buy foreign-made
rotors and can't get either parts or service.
11. Why should I buy one of your rebuilt rotors instead of a new one?
First of all, most of our rotors are the discontinued models which are no longer in factory
production. So if you're trying to replace your old one, you may not be able to get an identical
new one. Secondly, all of our rotors are rebuilt to original factory specifications.
In most cases
you can't tell that you're buying a rebuilt rotor. On our rebuilt rotors, we use stainless steel
hardware on the terminal board; our brake housing screws and lock washers are stainless; and
all of the mounting hardware including the mast clamps are also stainless for most models.
many ways, our "rebuilt" rotors are actually better than they were when they shipped as "factory
new." Norm's Rotor Service has been in business since 1961. Our reputation speaks for itself.
12. Why does the direction indicator meter stop and start and give an erratic indication when my rotor turns?
Contrary to popular belief, this problem is caused by a dissimilar metals problem in the rotor.
The rotor pot, which is the sensor for the position indicator, is made of tungsten wire with a copper
wiper. The pot shaft is turned by an aluminum housing. This combination causes corrosion to
accumulate on the pot, which then causes erratic movement of the meter. The condition can be
cured by cleaning the pot every year or two with an old toothbrush and some contact cleaner.
13. Why do I hear a hum in my rig when my rotor is turning?
Induction of the power transformer causes this 60-cycle hum in its near field.
Relocate the control
box farther from the receiver to solve this problem.
14. Can I use a Ham-2 rotor control box with my T2X rotor? Are the Ham-2, Ham-3, Ham-4 and T2X control boxes interchangeable?
Yes, for the most part, all of the 8-wire rotors except for the TR-2 series are interchangeable. You can use a TR-44 series 3; Ham-M series 3, 4, or 5; CD-44/Ham-2; CD-44/Ham-3; Ham-4; or T2X control unit with any of the listed rotors or vice versa. However, the Ham-M and TR-44 series 1 and 2 rotors were wired differently and are not interchangeable with anything else. So, trying to use a series 1 or 2 control on a newer rotor will destroy the rotor pot instantly.
To be sure that you have one of the interchangeable controls, verify that the motor start capacitor
is across terminals 4 and 8. To verify that the rotor is one of the interchangeable models, look
for the 500-ohm pot resistance across terminals 3 and 7. If your rotor and control unit pass these
inspections, they are interchangeable with others which also pass.
15. How can I get a meter that is south-centered for my control unit?
South-centered meter scales are available for almost all rotors. Just ask. If you have a Ham-4
or T2X, the meter scale is reversible, and you actually have a south-centered meter face printed
on the back of the north-centered face!
16. Should I have my antenna mast resting directly on the upper housing of my rotor?
Yes. Almost all of the rotors in medium and heavy service are capable of supporting over 1000 pounds of dead weight on the rotor housing.
17. What gauge of control cable is recommended for various distances between the rotor and the control box?
On the TR-44, CD-44, and CD-45 rotors, the standard control cable includes two #18 conductors
and six #22 conductors, and it's fine for runs up to about 300 feet. On the Ham-series rotors
and the Tailtwisters, this cable is good up to about 200 feet. If your run exceeds these distances,
move up to a heavy-duty cable, which includes two #16 and six #18 conductors which should
be good for runs up to 300 feet. For more detailed information on control cables,
contact us at the email link at the bottom of the page or click
18. How can I tell if my motor capacitor is bad?
If your rotor does not run or is hard to start, expecially in the colder months, the motor start/run
capacitor is a good bet for the fault. Most motor start/run capacitors are 108-155 mfd. caps,
but these are bipolar capacitors. It's often difficult, in today's market, to find these capacitors.
When checking a capacitor, it should be within 20% of rated capacitance and must show no signs
of corrosion or burning. DO NOT use a D.C. capacitor as a motor start/run capacitor.
suspect a bad capacitor, you can obtain one from many electric motor shops.
the wires from terminals 4 and 8 on your CDE/HyGain box and clip lead the new capacitor in place
to test. (See question/answer 14 for precautions.)
19. How should I position my rotor to bench test it?
When bench testing any of the HAM series rotors or the T2X (Tailtwister)
rotor, the rotor must be either in its normal upright position or inverted
(upside down) to test. The reason for this is that the brake wedge has a
slotted hole in it and, when the rotor is placed horizontally, the wedge is free
to move. If the wedge is down, gravity will let it lock in place, even
though the brake solenoid is engaged.
20. Is my rotor watertight?
NO! All rotors are designed to be mounted only one way and that is facing up.
For those who have a fold-over tower, the rotor must be removed if the tower is
going to be left in the folded over position. On the CDE/HyGain rotors there
is a tongue and groove connection and, when in the horizontal position, water
is allowed over this connection and the rotor will fill up with water. Since nothing
inside is protected, everything will rust very quickly. On the HD73 rotor
there is an up and a down. The older models do not have "This side up" printed
on the top but the later models do. When in doubt, look at the bottom of the
rotor. The bottom of the rotor
has a drain hole in the center of the bottom casting, and the bottom casting
has the terminal board.
21. To prevent slippage, I've been thinking of drilling a hole through my rotor and pinning the mast. Is this a good idea?
22. Payment Methods:
NRS accepts Visa, Mastercard, and Discover for payment of sales and service charges.
For sales transactions, where the exact amount is known beforehand, we will accept personal checks; call for confirmation of the exact amount and allow 3 to 5 working days for your check to clear our bank.
When paying by credit card, you must supply us with the credit card number, the expiration date, and the card ID number (This can be found in the box on the back of the card, where you sign your name. It is the last three digits, after the last four digits of the credit card number. For example, card number 1234 1234 1234 1234 (456). In this case the 456 is the card ID number.)
You also need to tell us if the address you supply us with is the same address as where you receive your credit card bills. If not, you need to give us the house number or P.O. Box number and the zip code of the address where you receive your credit card bill. For example, if you are having us send a part or rotor to your office address at 12345 Smith Street, Anywhere, MD 12345, but your credit card bills go to your home address at 345 Jones Avenue, Anywhere, MD 12346, you need to send us the numbers 345, not the street name, and the zip code of 12346.)
Also, if you have an e-mail address, please include it so we can send you an e-mail copy of your invoice, showing what was done or sent, and the date it was sent.
Copyright © 1996,1997,1998,1999,2000,2001,2002,2003,2004,2005,2006,2007,2008,2009,2010,2011,2012,2013,2014
Norm's Rotor Service