(13) With EXPOSURE DELAY/NORMAL switch S102A set to DELAY and the hood down,
+12.5 V is applied through S107 and S201.
This causes Q1 to conduct and Q3 cuts
o f f .
C1 and C2 charge, keeping Q3 off.
With Q3 off, +12.5V is applied to Q2,
keeping Q2 on and K1 energized.
After approximately 3 to 6 sec, Q3 conducts and Q2
cuts off, de-energizing K1.
T h e r e s e t n e t w o r k i s d e a c t i v a t e d , r u n / s t o p f l i p - f l o p is
enabled, and the CRT is unblanked.
A u t o m a t i c p l a t e n l i f t e r ( A P L ).
The APL raises the hood after the first
printing, allowing the transport control to advance the paper.
T h e n i t l o w e r s t h e
hood for the next exposure.
The APL control circuits ensure that the APL does not
operate during exposure, RPT operation, and single-print operation.
NOTE
For discussion purposes, printer is in process of completing exposure
c y c l e .
Upon completion of the first exposure, exposure lamp DS107 goes out and the slow
a x i s t o g g l e r e s e t s t h e r u n / s t o p f l i p - f l o p.
T h e r u n / s t o p f l i p - f l o p t r i g g e rs
electronic switch Q3 and Q4 on card 4TC1.
The switch is turned on and energizes
relay K201.
Relay K201 applies 120 V ac primary power to APL motor B201 and
solenoid LS201.
The motor starts and lifts the hood clear of the print stage. When
solenoid LS201 is energized, it applies +12.5 V through its contacts to the relay
control circuits on exposure delay card EDC1.
Relay K1 energizes and prevents the
run/stop flip-flop from being triggered when the hood is up. When the hood clears
the print stage by approximately 2 in.,
the RPT hood microswitch S110 closes,
applying 120 V ac through the K301 contact to repeat revolution counter CTR302.
Repeat revolution counter CTR302 energizes the auto timer which removes +12.5 V from
card 4TC1 via print counter CTR201 and APL single/multiple print switch S203. Elec-
tronic switch Q3 and Q4 then shuts off and de-energizes relay K201. The APL motor
stops while the RPT is advancing.
Upon completion of the paper advance, +12.5 V is
reapplied to electronic switch Q3 and Q4 on card 4TC1. Electronic switch Q3 and Q4
re-energizes relay K201 and turns on the APL motor. The motor in turn operates the
APL to close the printer hood.
As the hood closes, cycle switch S202 applies a
ground to a 150 msec, one-shot multivibrator consisting of Q1 and Q2 on card 4TC1.
The multivibrator shuts off electronic switch Q3 and Q4 and ensures it remains off
for a 150 msec period.
Relay K201 de-energizes and removes primary power from the
APL motor, solenoid LS201, and S201.
When the solenoid de-energizes, it causes Q2
and K1 on card EDC1 to de-energize.
K1 contacts then apply a +12.5 V start pulse to
a c t i v a t e t h e r u n / s t o p f l i p - f l o p t h r o u g h R E P E A T s w i t c h S 1 0 6 . T h e r u n / s t o p f l i p - f l op
starts the next exposure cycle.
The printer continues to cycle until APL print
counter CTR201 counts the desired number of prints. Once the desired number of
prints is reached, an internal switch opens in CTR201. This removes the +12.5 V
from the APL control circuits and APL operation is terminated.
9-12
TM 5-6675-319-14
c .
