TM 11-6720-242-35
Item
Malfunction
Probable Cause
Corrective Action
9
ADAS ineffective
a. Cathode ray tube
b. Lens-mirror assembly
c. Capping cam or capping link c.
Check and replace defective part
10
End of film switch defective
Sensitive switch or switch actuator
Check and replace defective part
b. Troubleshooting Camera Control.
Malfunction
Probable Cause
Corrective Action
Item
1
Slit in focal plane and aperture
a. AEC log amplifier
opening improperly
R3 as directed
controlled
b. Photocell amplifier
b. Check photocell amplifier AR2
defective parts.
c. Scaling accuracy
c. Check the scaling accuracy (para
4-7f). Replace defective parts.
d. Motor speed
2
Improper switchover from
Resistor R22 on control board
Check mode switch circuit (para
automatic to pulse operation.
assembly.
4-8a). Replace defective parts.
3
Incorrect timing between
a. Resistors R34 and PR35 on control
pulses.
board assembly.
b. Resistor R10 on control board
b. Check V/H VERT-1 circuit
Replace as directed.
c. V/H scaling network
c. Check V/H scaling network (para
4-8d). Replace defective parts.
d. Voltage divider R13, R14, R15,
and VR1 on control board
defective parts.
assembly.
4
Scan drive not functioning
a. Gain or linearity circuits on scan
or scan motor speeds are
board assembly.
through d). Replace defective
erratic.
parts.
b. Scan control relay K1 on scan
b. Check scan control relay K1 circuit
board assembly.
(para 49f). Replace defective
part.
5
Dynamic motor brake not
Transistors Q12 and Q13 on scan
operating.
board assembly.
defective part.
c. Troubleshooting Control Panel.
Malfunction
Probable Cause
Corrective Action
Item
1
Radio signals affecting Radio
camera operation
2
Frames remaining indicator
a. Indicator defective mechanically
a. Replace frames remaining indicator
inoperative
or electronically
b. Pulse circuit on interface board
b. Test circuit (para 44). Replace
assembly.
malfunctioning part.
3
No +22 volts regulated
a. Transistor Q3 on interface board
a. Check Q3 and replace, if necessary,
control voltage or voltage
assembly
para 46).
variable.
b. Resistor R8 on interface board
b. Check R8 and replace, if necessary,
assembly.
c. Voltage regulator VR3 on interface
c. Check VR3 and replace, if
board assembly.
necessary, (para 46).
4
No pulse scan control relay
Fail safe circuit on interface board
K1 on scan board assembly
assembly.
and replace malfunctioning part
5
No annotation pulse for
Annotation circuit on interface board
aircraft equipment.
assembly.
and replace malfunctioning part.
6
Extra picture switch
Extra picture circuit on interface
inoperative.
board assembly.
and replace malfunctioning part.
7
No IMC operation
Q4 or R10 on interface board
assembly.
Replace malfunctioning part.
Change 1 4-4