[amsat-bb] Re: G5500 Rotor Issue
Alan P. Biddle
APBIDDLE at UNITED.NET
Tue Aug 19 14:30:35 PDT 2008
First thing to do is swap the connectors between the rotators and see if the
problem follows the rotator. The controllers are essentially identical,
except for the meter scales. That test will eliminate anything external to
If the problem does follow the rotator, check the DC continuity of the 3
motor leads. That should be the bottom 3 screws on the controller. Expect
to see about 5 ohms or so with the wires disconnected from the controller.
If that is good, then it is _probably_ the phase shift capacitor. With that
open, the motor will hum, and may even move a bit with no load, but will
have little or no torque. Unfortunately the capacitor is inside the
elevation rotator. Replacing it is straight forward, but tedious, and
messy. Been there, done that, last month.
More information about the AMSAT-BB