TM 5-6675-325-14
(6) When PRINT switch S6 is depressed, contacts are opened producing a high
signal at TP6 on the logic board.
The logic board now has high indications at TP5,
6, 7, and 9.
These are all conditions required to initiate the print cycle. The
mirror motor logic circuit applies start signal from integrated circuit U29 to
transistor V4.
This fires triac V2 which energizes mirror motor M3.
(7) When the mirror motor is energized, the main viewing mirror assembly
begins to move forward from the “home” position.
The cam, which is driven by the
mirror motor, starts to rotate counterclockwise, operating switches S9, 10, and 11.
The contacts of mirror forward switch S11 remain open, and this tells the logic
board via TP9 to keep the mirror motor running.
The contacts of mirror home switch
S1O close.
This puts TP7 low.
The contacts of exposure lamp switch S9 open to
remove voltage from one side of exposure lamp L1.
The paper drive begins when the
main viewing mirror starts to move forward and away from the mirror’s “home”
position.
Before the paper drive motor can start, the logic board needs to see the
correct signals from:
(a) Optical sensors 0S1 and 0S2.
With no paper blocking light from the
light-emitting diode (LED) to the optical sensors, they produce a high signal at TP5.
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