TDS/C/R/CNC (Feb 1985) - Speed control problem

[bradders]

Owner writes.............

Hi

New to this site.

We have a problem with the speed contol on our lathe.

Model:TDS/C/R/CNC (Feb 1985)

When in manual mode, the spindle will start, however when we try to vary the speed, via the +ve / -ve keys on the spindle speed section of the keyboard, there is no response in either direction.

At present the spindle speed is varying (self-fluctuating) between 100RPM & 120RPM.

Does anybody have a solution?

Thank You
Martin