CG5 Goto mount faulty

[Astronut]

I haven't had much luck with my current setup considering how little it's been used - see sig - but that's another story. Now the mount is faulty.

First star alignment slewing starts off fine but halfway through slewing to the first star, the declination motor stops (RA motor seems fine) and a few seconds later it starts up again. This repeats until the 'scope is pointing below the horizon at which point I switch off and try again - same thing happens.

I have to do without goto and find things manually but tracking is working fine but then it would be as the declination axis is not in use during tracking.

I can slew manually with the handset but if I adjust the slewing rate (1-9) the declination axis always slews at maximum rate (RA slewing rate adjusts normally). Also when I'm slewing in declination with the handset, the motor stops dead when I let go of the slewing buttons instead of slowing down gradually as it does in RA.

I think it may be a hardware fault because when I connect the short external coiled declination axis cable at both ends, the red LED power light goes off. I thought there may be a short somewhere in the head but I've had the covers off and nothing seems untoward (no snagged cables, loose connections, etc). Also the external declination cable has been tested with a continuity meter revealing no faults.

Could it be corrupt firmware?

Help, I'm stumped - any ideas?

Ian

[barkis]

Ian,

There was a fairly recent Motor Control Firmware update for the CG5 -GT Mount.

I have the zip files of both the Hand, and Motor Control F/W's.

But they are too large to attach to this post.

I could send them as an email attachment if you want them.

Ron.

[Astronut]

Thanks for the offer Ron but as far as I'm aware the latest firmware is available on the Sky @ Night mag CD's. If not I can always download from Celestron's site.

Besides, I'm not entirely convinced it's a firmware fault with the red power light going off when the cable's plugged in.

[malc-c]

How are you powering the mount. I've had similar problems with an EQ5 which turned out to be related to a poor power supply. Strangely its always the DEC motors that suffer when the voltage drops. You need a 12v supply capable of 2 - 3 amps (ie one that can supply 12v under that kind of load.)

[Astronut]

I'm using a Skywatcher 17ah portable unit, similar in spec to the Celestron one. I've always used this unit from day one and it's never been a problem.

I've ruled out the power supply as the problem as I've tried the mount with Ian's (starflyer) huge leisure battery and the fault with the mount is still there.

[Psychobilly]

I would have a qick look at the power socket on the mount....

If the DC jack on the mount has a "split" center pin then ease the two halves apart slightly... also try and strain relieve the plug when it's plugged into the socket.. I form a loop of cable and then tape the free end to the mount...

[continuum]

After checking the power supply you could try swapping the Dec motor with the RA motor and see if you get the same problem in RA. That should prove it's the motor.

I say this from experience with my CGEM where it proved to be the encoder on the end of the motor when I had a very similar experience to you.

A new motor/encoder would have to be obtained if that is the case.

RonJ

[Rob Severn]

Which power cable are you using ? If it's the Celestron one supplied with the mount, throw it away. Try using the Skywatcher cable suppiled with the power tank. I had many many mount woes and it was all down to the cable.

Best of luck

[Astronut]

Checking the pin was one of the first things I did. A faulty motor encoder sounds plausible. I'll check that but first I'm going to dig out my receipt as it may still be under guarantee. (less than 2 years old).

[spaceboy]

Have you tried a factory reset?

[yesyes]

Have you tried a factory reset?

Yes, this is what I would suggest trying as well. I had some weird movement with my CG5 (though your symptoms sound slightly different).

After a factory reset (via the Utility menu IIRC) solved the issue.

[Astronut]

re. factory reset, tried that too. No luck

[Hedgerow]

Hi Ian,

I have had the same problem and am still in the process of getting it fixed (now with David Hinds via Green Witch). You might like to check out my thread.

http://stargazerslounge.com/equipment-discussions-help-mounts/151454-help-needed-goto-mount-problem.html

Cheers P.eter

[Hedgerow]

Ian,

David Hinds have just informed me that my mount cannot be economically repaired. I still do not know what the actual fault is. They suggest buying a new one!!!!

Peter

[Astronut]

Ian,

David Hinds have just informed me that my mount cannot be economically repaired. I still do not know what the actual fault is. They suggest buying a new one!!!!

Peter

Just read your thread. Not a good situation. I've just re-tried my mount in the vain hope it may be alright but the symptons persist.

I might ring FLO as it's less than 2 years old. If it's not covered under Celestron's guarantee or David Hinds are not willing to repair it, I may cut my losses and bin it, sell the OTA and save up for another big dob (with tracking of course but I can live without goto).

[brantuk]

You can take the motors off and add a pair of slo mo controls and sell it for £120 'ish if you do decide to bin it. At least you'd get something back

But as for not being repairable economically - I think that's "iffy" cos you can replace either of the motors or control boards very easily if you can get hold of them from Celestron. They just unplug or unscrew off. The handset can be replaced too. The labour wouldn't cost a lot to do that, and you could even do it yourself

[Starflyer]

This is terrible Ian, you can't just bin it. I know how little use it's had and also how this is just another problem in a long line of problems with this scope / mount. I should also mention that I know FLO have been extremely helpful with the other problems you've had with this setup from day one.

I'd definitely try for a repair under warranty before doing anything else, I know you're fed up with it but you can't just write off an expensive bit of kit. If it was me and I got a negative response from David Hinds I'd be looking at consumer law to help me out.

[FLO]

Somebody just sent me a link to this thread...

Astronut has a problem with a mount bought from us less than two years ago. That one is easy, if he contacts us with details we'll dispatch a replacemant motor. No problem

Unless I am mistaken Hedgerow bought a five-year old secondhand mount earlier this year that was originally purchased from DHinds. He is in communication with Lee at Greenwich. Lee is one of the good guys, I feel sure he will do his best to help.

ATB,

Steve

[Astronut]

Steve, I'll ring asap this week. Thanks. Not sure if a replacement motor would sort it but it does seem (from the symptoms) that it would.

Just checked my receipt and it is less than 2 yrs old. Doesn't seem like more than a year but time flies.