First off .. I am BLOWN AWAY by the fact you guys have responded with your knowledge and advice. The idea that someone would offer to help with a 20 year old desk is just wonderful. If you ever have any Motioncontrol or film camera issues, you can get my number from an internet search.
Keith first ..
Was there any signs of corrosion around the battery, discolour track etc.
I didn't THINK so, I gave it a good clean and some pcb cleaner and it seemed ok .. I was looking for a trace on the tracks (To find the test point) NOW you have told me where the test point is so I will check a voltage from there (I will send a picture of the PCB)
Ian ..
This is SO useful, what I omitted is that I didn't have a power supply so I made one out of an ATX PSU. Now I WOULD have said "And that works fine" My assumption being that that was what the three LED's are.
Which leads me to kgallen, Who has put me onto a source of a spare PSU. and in Leeds where I will be next Thursday.
I'm overwhelmed, I do have to make a slight "confession", there is no real object to this, Yes of course it might be a thing for the village hall, but in truth I have any number of enttec boxes and Dragonframe licenses, which would be far more suitable. I spend my life (as you guys probably do too) making, testing and fixing "Stuff", if it had been faced with a 20 year old motion control anything I'd have put it on ebay for 99p and said "first person to come and collect can have it". For some reason fixing something you don't really NEED is like an odd perversion of mine. (On the other hand showing the guys in the robotics club how DMX works would be fun).
I will post an update later today ..
Thankyou all so much .. This has really made my day ..