Vixen Skysensor 2000 woes

[Ludd]

I have owned a lovely old Vixen GPDX mount for a good number of years and it has served me very well.  The Skysensor drive controller has been a delight - not an intuitive UI but amazing performance. 
 

Until recently, that is.  I am now suffering from an inability to do a two star alignment, the tracking is unreliable and the motions are very inconsistent when using the direction buttons, with the scope moving in apparently random directions with terrible jittering. 
 

I don’t have the knowledge or skills to diagnose the problem, and I am seriously considering abandoning the Skysensor.  I might switch to plain motor drives if I can find a cheap set, but in the meantime I will be using my AZ4 and my astrotrac.  
 

Does anyone know of anyone not too far away (from Aylesbury area) who might be able to do a diagnosis?

[dweller25]

Cannot help with the Skysensor 2000, but have some good motors and controller that will fit the GPDX  if required.......

 

Edited January 21, 2020 by dweller25

[Ludd]

Oh, nice one!   I had these drives on a previous GP and they were great.  Will send a message later.  

[pete_gamby]

Have you ever changed the internal battery on the Skysensor? It could be that it has come to the end of its life and that's why you're seeing the odd behaviour.

[Ludd]

Hi Pete

Good point - I did change it about 5 or 6 years ago, but I would have thought it should still be OK after that time.   If I can find a meter I will check the battery. 

[Ludd]

Thanks to Dweller25 I shall be trying life with good old fashioned motors!

Edited January 24, 2020 by Ludd

[pete_l]

On 22/01/2020 at 11:41, Ludd said:

Hi Pete

Good point - I did change it about 5 or 6 years ago, but I would have thought it should still be OK after that time.   If I can find a meter I will check the battery. 

I have a SS2K with my GPDX (still going strong).
The battery only powers the internal memory when the unit is switched off. If you are not losing your settings between sessions, then the battery is fine.
The SS2K does suffer from issues with the thick cable from the hand controller. Sometimes one of the wires will become frayed or break entirely. The symptoms you describe could be caused by an intermittent connection there. The control of the motors comes directly from the hand controller, which could explain the jittery motion.
That is where I would look first. After that a close inspection of the power cables and connections.

[Ludd]

Ah, thanks for that.   Yes, that awful cable!  I shall have a look but in the absence of any testing equipment (or relevant knowledge) I may have difficulty with a diagnosis.  

[Ibbo!]

My cable has a break in it somewhere.

Gone over to the synscan.

 

[Ludd]

Update: after lots of testing, I am satisfied that the direction buttons on the controller are correct and consistent now.  I just need clear skies so that I can test the alignment procedure again.  

I have opened up the gears and they are all sitting nicely.   One of the cogs on the R.A. drive was slightly high on its spindle (so only engaged across 80% of the thickness or its neighbour) so I sorted that out.   Grease and internal battery are fine. Still no backlight on the display so I have fitted a tiny LED anglepoise light on the mount.