[amsat-bb] Re: G-5500 Troubleshooting

John Meeks jmeek at gaslightmedia.com
Sun May 2 14:17:56 PDT 2010

i8cvs wrote:
> ----- Original Message ----- 
> From: "John Meeks" <jmeek at gaslightmedia.com>
> To: <amsat-bb at amsat.org>
> Sent: Saturday, May 01, 2010 11:22 PM
> Subject: [amsat-bb] G-5500 Troubleshooting
>> One more thing... Given that the cable tested OK, what does the open 
>> reading from 6 to 4 suggest? My reading of the schematic diagram is 
>> sketchy at best.
>> Any and all help will be greatly appreciated.
>> John Meeks
> Hi John, KC8ZFN
> After the carefull troubleshooting you did and described the actual open
> reading from 6 to 4 in the az. motor suggests two possible autcomes.
> 1 ) The limit switch SW6 inside the rotator is defective and is an open
>       circuit
> 2)  The winding of the motor connected to limit switch SW6 is open
>       so that the motor cannot run nor left and nor right
> Since 6 and 4 are an open circuit the electrolitic unpolarized capacitor
> inside the motor appears to be not involved in this type of problem.
> Please let me know just for curiosity the result of your investigation
> but I believe that you have to open the azimuth rotator.
> Best 73" de
> i8CVS Domenico
Thanks for confirming my conclusions so far, Dom. 

I've Got the Az rotator on the bench. It looks and smells new. The limit 
switches present a closed circuit until the swtich is activated when 
they open as expected.

Looking for continuity between the pin corresponding to to A6 (black 
wire) and one of the limit switches (red wires) shows 3.7 ohms, and to 
the other switch (green wires) is an open circuit. I'm thinking this 
should be continuous also. If this is the case, what are my options?  
Has anyone had success repairing this motor?

Thanks for the help.
John Meeks


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