Under Manual Control

1. Either (a) Depress the TURNTABLE SELECTMANUAL control button on the Control Desk (the button must be illuminated),
   or (b) Switch over to Engineering Mode by pressing the ENGCOMP button.
2. Select fast or slow motion on the Engineering Rack.
3. Press the rotation + or - buttons as appropriate. Note that the motion as indicated on the Engineering Rack is counter to the change of position angle! The correct value of the position angle on the sky is shown on the Information Display; the value on the Engineering desk equals 360-PA and in addition includes a small encoder zero-point correction.

Beware: do not drive through angle 220 on the Engineering Rack, i.e. Position Angle 140 on the sky (and Information Display), because the turntable will hit a limit switch and you will have to go all the way round in the opposite direction. If you do hit the limit switch somehow, signalled with the red light on the Engineering Rack below the ``position angle'' display, back out of it in slow motion.