[amsat-bb] G-5500 az rotor failure

[k.swaggart at charter.net]

The problem turned out to be a loose setscrew at the motor. Easy fix, but
took about four hours to reassemble the rotor so the limit switch was
tripped correctly and then get the antennas reattached. Anyway, back in
business.

 

I took quite a few photos of the az rotor disassembly and I'll add them to
my G5500 page within the next few days:

http://www.ocrg.org/W7KKE/rotor/rotor.html

 

73,

Ken, W7KKE

 

From: k.swaggart at charter.net <k.swaggart at charter.net> 
Sent: Friday, August 23, 2019 10:39
To: AMSAT-BB (amsat-bb at amsat.org) <amsat-bb at amsat.org>
Subject: G-5500 az rotor failure

 

This morning I found my G-5500 will not move left or right. Not even a
wiggle. Took some measurements and the wiring appears to be intact but I
don't understand the 40 Vac readings when the rotor is connected to the
control box. Here are my readings taken at the control box end of the
wiring:

 

Rotor connected to control box:

Common (pin 6) to Left (pin 4)  Press Left: 28 Vac  Right: 40 Vac

Common (pin 6) to Right (pin 5) Press Left: 40 Vac  Right: 28 Vac

 

Rotor disconnected. Measuring control box terminals:

Pin 6 to 4  Press Left: 29.5 Vac  Press right: 0

Pin 6 to 5 Press Left: 0  Press Right: 29.5 Vac

 

Measuring rotor cable at control box, disconnected from box:

6 (brown) to 4 (blue) 5.3 Ohms

6 (brown) to 5 (orange) 5.3 Ohms

4 (blue) to 5 (orange) 8.9 Ohms

 

Any suggestions before I pull the rotor off the mast?

 

73,

Ken, W7KKE