At 09:24 PM 1/5/97 -0500, alsopb@VANCE.NET wrote:
>Guys,
>
>I'd like a bit of advice on troubleshooting what appears to be a HamIV
>rotor problem.
>I have a 5 year old Ham IV that rotated my 4 element Gem Quad
>flawlessly. I recently
>added a Mosley rotatable dipole (12 pounds, not much additional torque
>needed I think) and things went fine for a while.
>
>Lately the rotor has been getting more and more difficult to get
>started. It's at a point where I have to do something.
>
>The symptoms are:
>1) It "sticks" at random spots on the compass. Sometimes can be unstuck
>by repeated attempts.
>2) The brake is fully retracting. I've gone out and listened to its
>repeated snap's while XYL operates it.
>3) The resistance checks indicate the same readings as when it was first
>installed.
>4) The rotor is putting out about 26 volts AC at the rotor when the CW
>or CCW key is pressed.
>5) Rotor was refurbished by CATS 4 months ago.
>
>I can think of three things:
>1) Starting capacitor is bad (although ohmmeter check indicates OK)
>2) Gears stripped inside rotor
>3) Binding somewhere. Thrust bearing? (although visually everything
>looks fine, thrust bearing is 3 months old and I can see things seeming
>normal when wind twists array)
>
>Any advice before I lower the mess?
>
>Thanks.
>
>Brian/K3KO
>Vance Net Inc
Brian, sounds like you may have one of two problems. One could be the
potentiaometer in the top of the rotor. When it goes, the rotor control
will not indicate that the rotor is turning, when in fact it is. To find if
this is hapening, just have your xyl to turn the rotor while you watch. If
this is not the problem, and the rotor is infact not turning, then it
probubly has the second reason.
The second cause of these simptoms, is a borken or cracked ring gear in the
rotor. This could also be caused by broken, or stripped motor gears as well.
In any event, the rotor will have to come down to find the problem, and
repair it. Fortunatly these rotors are very semple to repair, and C.A.T.S.
has all of the replacement parts that you may require.
I have two of these rotors. One is on the tower and the other is kept as a
spare. When one fails (and they will fail), I simply swap it out for the
other. Then, I can repair the spare at my convience.
Good luck
Don Gaikins
W0VM
don_gaikins@partyline.net
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