TM 9-1240-382-34
TROUBLESHOOTING
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
b.
If tube does not light, replace regulator
c.
If malfunction is not corrected, replace
elbow assembly.
3. NO NIGHT CHANNEL IMAGE, LOW BRILLIANCE
OF NIGHT IMAGE, OR NIGHT IMAGE FLICKERS
OR MOVES.
NOTE
Cover objective lens and
apply 24 volts dc power
to the elbow assembly.
Step 1. Check the shutter switch.
a. Move switch to ON position.
b. If malfunction is not corrected, proceed
to step 2.
Step 2. Ensure that TUBE control knob is properly
adjusted.
a. Turn control to obtain sufficient image
brightness.
b. If malfunction is not corrected, proceed
to step 3.
Step 3. Ensure that contact is not corroded.
a. If contact is corroded, clean the
contact (p 2-10).
b. If contact is not defective, proceed
to step 4.
Step 4. Check that image intensifier tube is not
defective.
b. If malfunction is not corrected, proceed
to step 5.
Step 5. Check continuity of TUBE variable resistor (R3)
a. If continuity check fails, replace
variable resistor or resistor (or both
as necessary.
b. If malfunction is not corrected, replace
the elbow assembly.
2-3
