Litton JDH-2250-CG-1C Servo Motors and fitted with 721B1-508-315-5KM Encoders (L

Hi,

I have the above Servo Motors but no information on how to drive them
etc. I am new to CNC and therefore am creating my 'information chain'.
The units are 6 wire with 2 wires going to brush holders on the side of
the motor body (+ve and -ve). I am assuming that these are DC motors.
They have come from an old ZETA 9 Plotter.

Can any one enlighten me on Servo /Encoder systems and are these good
to have type motors or should I just go and buy some steppers to get
going.

All help greatfully received.