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Equipment Discussions >> Equipment

Pages: 1
olsie
member


Reged: 06/09/05
Posts: 58
Loc: Rockford, IL
Rcx400 one of three focus motors malfunction
      #3434001 - 11/07/09 12:01 AM

Hi y'all
I have an older Rcx i haven't used in awhile. Started it up and one of the three focus motors will only rotate in one direction until it reaches its limit. Is this a common problem? Easy fix? Or do I need to return for repair?

Thanks

--------------------
Olsie

RCX 10"
Orion 70mm
DSI-Pro
ST-9XE
EVOLT-500 DSLR


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jrcrillyAdministrator
Refractor wienie no more
*****

Reged: 04/30/03
Posts: 25179
Loc: NE Ohio
Re: Rcx400 one of three focus motors malfunction new [Re: olsie]
      #3434046 - 11/07/09 01:15 AM

Those use servos and what you describe is a typical "open loop" situation. That means that the encoder isn't being read properly. On that model it's usually caused by a connector problem in the encoder cabling.

--------------------
John C
Urban Observatory
A&M/Astreya 76mm F/6 APO
TMB/LOMO 80mm F/7.5 APO
Tak FSQ-106N F/5 APO
Meade 178ED F/9 "APO"
Meade ETX-125AT
C14
Teeter 20" F/3.8 truss Newt w/ServoCat
CI-700, NJP, GPDX/SS2KPC, CG5-GT
ST-10XME, DSI Pro


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olsie
member


Reged: 06/09/05
Posts: 58
Loc: Rockford, IL
Re: Rcx400 one of three focus motors malfunction new [Re: jrcrilly]
      #3434050 - 11/07/09 01:28 AM

I recognize and understand that situation. Are there diagrams available so I can disassemble and check the cabling?

BTW, does Meade have any e-mail addresses? I can't seem to find any.

--------------------
Olsie

RCX 10"
Orion 70mm
DSI-Pro
ST-9XE
EVOLT-500 DSLR


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jrcrillyAdministrator
Refractor wienie no more
*****

Reged: 04/30/03
Posts: 25179
Loc: NE Ohio
Re: Rcx400 one of three focus motors malfunction new [Re: olsie]
      #3434071 - 11/07/09 01:55 AM

Quote:

I recognize and understand that situation. Are there diagrams available so I can disassemble and check the cabling?

BTW, does Meade have any e-mail addresses? I can't seem to find any.




Meade doesn't like to use email for customer contacts. I'd be surprised if support@ and engineering@ didn't reach someone, though...

You used to be able to set up a support ticket from their website (I presume you still can). Those always received responses when I used them. You won't get schematics, though. I haven't seen any myself but there might be some out there. The way I remember those, the three motors are fairly accessible at the rear housing and there's a control board back there as well. The relevant cabling would be between the motor units and that controller.

--------------------
John C
Urban Observatory
A&M/Astreya 76mm F/6 APO
TMB/LOMO 80mm F/7.5 APO
Tak FSQ-106N F/5 APO
Meade 178ED F/9 "APO"
Meade ETX-125AT
C14
Teeter 20" F/3.8 truss Newt w/ServoCat
CI-700, NJP, GPDX/SS2KPC, CG5-GT
ST-10XME, DSI Pro


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olsie
member


Reged: 06/09/05
Posts: 58
Loc: Rockford, IL
Re: Rcx400 one of three focus motors malfunction new [Re: jrcrilly]
      #3434087 - 11/07/09 02:49 AM

That's very helpful advice.
Thanks a heap.


olsie

--------------------
Olsie

RCX 10"
Orion 70mm
DSI-Pro
ST-9XE
EVOLT-500 DSLR


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olsie
member


Reged: 06/09/05
Posts: 58
Loc: Rockford, IL
Re: Rcx400 one of three focus motors malfunction new [Re: olsie]
      #3434826 - 11/07/09 03:04 PM

I found success on three fronts thanks to your advice.
First, I was able to swap out cabling on two motors and the problem remained with the B motor (1-2 O'clock position). I also successfully removed the motor assembly and sent a RFQ for a replacement. The e-mail, thus far, has not been returned. I'm sure the problem is with the encoder module but I don't know if they will sell it separate since it must be properly aligned.

Thanks again.
Olsie

--------------------
Olsie

RCX 10"
Orion 70mm
DSI-Pro
ST-9XE
EVOLT-500 DSLR


Post Extras: Print Post   Remind Me!   Notify Moderator  
jrcrillyAdministrator
Refractor wienie no more
*****

Reged: 04/30/03
Posts: 25179
Loc: NE Ohio
Re: Rcx400 one of three focus motors malfunction new [Re: olsie]
      #3434891 - 11/07/09 03:46 PM

Quote:

I'm sure the problem is with the encoder module but I don't know if they will sell it separate since it must be properly aligned.

Thanks again.
Olsie




You are welcome. I know that it's no fun having something broken but I think it's better to at least know what's wrong!

I recently had an encoder board fail in a Celestron drive motor. As you suggest, they wouldn't sell me just the board - but the good news was that the complete motor assembly was only about $40. I hope that Meade is as gentle with you.

--------------------
John C
Urban Observatory
A&M/Astreya 76mm F/6 APO
TMB/LOMO 80mm F/7.5 APO
Tak FSQ-106N F/5 APO
Meade 178ED F/9 "APO"
Meade ETX-125AT
C14
Teeter 20" F/3.8 truss Newt w/ServoCat
CI-700, NJP, GPDX/SS2KPC, CG5-GT
ST-10XME, DSI Pro


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