(3) Extend the light drawer and replace the defective lamps.
(4) Insert the light drawer and tighten the knurled screws in the front panel and the wing nuts at
the rear of the printing head.
(5) Replace the connector on the rear of the light drawer.
f. Exposure time and number of prints switch replacement (fig. 2-5). There are three exposure time
and two number of prints switches and two number of prints counters. Each is replaced in an identical
manner. Proceed as follows:
(1) Remove the cover from the top of the control unit by removing 11 screws and washers from
the top and five screws and washers from the rear of the cover.
(2) Remove the six screws holding the face plate to the control box. Remove connector P2 from
(3) Remove the two screws (4), nuts (7), washers (5), and lockwashers (6) from the faceplate
(13) and the four locking clips.
(4) Disconnect the jack at the rear of the switch.
(5) Install the new switch and secure with the screws, washers, lockwashers, nuts, and locking
(6) Reconnect the jack on the rear of the switch.
(7) Reconnect P2 to J2 and replace the six screws on the faceplate.
(8) Replace the control unit cover and secure with the 16 screws and washers.
g. Printing glass replacement.
(1) Raise the driving mechanism.
(2) Loosen the two knurled thumbscrews that are located at each of the four corners of the light
box and swing the metal retainer away from the corners.
(3) Lift up and remove the printing glass.
(4) Set the replacement printing glass in place over the diffusing glass.
(5) Secure the glasses by swinging the metal retainers across the corners and tightening the