Thanks Narayan,
I have replaced the guide camera cable twice but not the mount cable, although I have replaced the RS232 to USB part of the mount cable for one that works with Win7.
All the other software I use seems to work perfectly, Alignmaster, Ascom, Direct RS232 to scope, (built my own controller with a pic), etc
So I'm not sure it is the mount cable as it is sending data.
With the DEC in PHD turned off, and if I have good polar alignment, the scope tracks for about on average 25 min before I stop and start PHD again so comms appear to be OK as is the hardware. I've got reasonable PEC on RA, and have turned it off/on with little difference. Balance is good. Goto works great, especially in high precision with objects centred. Camera lined up, everthing is tight and solid.
I have had a new dec motor drive board fitted by Bintel and the issues have kinda started after that, but everything else works with this board in DEC so I'm not sure where to look. I've used different laptops with different versions of PHD as well.
As I mentioned before, it was working fine for about 2 1/2 years until one night all of a sudden, no worky. It's got me stumped.
Cheers,
Damien.