TM 11-5855-239-23
Table 2-2.
Organizational
Troubleshooting
Corrective action
Possible
cause
Trouble
a.
Replace batteries
1.
Light source failure . . . . . . . . . a. Weak or dead batteries . . . . . . . . . . . .
b.
Replace lamp
b. Defective lamp . . . . . . . . . . . . . . .
c.
Replace reflector
c. Rusted or corroded reflector . . . . . . . . .
d.
Report to DS maintenance
d. Defective switch . . . . . . . . . . . . . .
e.
Clean contacts
e. Contacts corroded . . . . . . . . . . . .
a. Replace metascope
Weak or no illumination of image a . Image tube defective . . . . . . . . . . . . .
2.
b. Replace battery
b. Weak or dead battery . . . . . . . . . . . .
tube.
c. High voltage power supply defec-
c. Report to DS maintenance
tive.
d.
d. Switch defective . . . . . . . . . . . . . .
Report to DS maintenance
Image tube not seated properly . . . . . . . . . . Report to DS maintenance
3.
Poor image at long range . . . . . . . .
a. Image tube failure . . . . . . . . . . . a. Replace metascope
4.
Image pulsates . . . . . . . . . . .
b. Report to DS maintenance
b. Image tube contact ring not mak-
ing contact.
Replace metascope
Image tube defective . . . . . . . . . . . .
5.
Bright flash in image tube or
sparking
around
edge
of
image.
a. Dirty image tube . . . . . . . . . . . a. Replace metascope
6.
Short viewing time . . . . . . . . . . .
b. Dirty high voltage power supply . . . . . b. Report to DS maintenance
ORGANIZATIONAL MAINTENANCE
Section Ill.
(2) Remove corrosion from the battery con-
tacts with fine abrasive paper.
(3) Replace the packing ring if the rubber
(1) Unscrew the lockring counterclockwise.
is damaged or deteriorated. Lubricate new pack-
ing ring with pneumatic grease MILG4343.
(2) Disassemble the parts as shown.
(4) Reassemble the parts as shown.
(3) If necessary, clean the filter and reflec-
tor with lens tissue or a soft lint-free cloth.
26. Metascope
(4) Check the lamp and switch contacts for
corrosion. Clean with fine abrasive paper.
shown.
(5) Replace the packing rings under the
thumbscrews if the rubber is damaged or deter-
iorated. Lubricate new packing ring with pneu-
23910).
matic grease MIL-G4343.
( 1 ) Disassemble as shown.
(2) Remove corrosion from the battery con-
22 ) .
tacts with fine abrasive paper.
(3) Reassemble the parts as shown.
( 1 ) Disassemble the cap assembly as shown.
