Table 2-2. Troubleshooting--Continued
a. Dirt on entrance or exit optics.
a. Clean surfaces of optics.
Image not clear or out of focus.
b. Diopter knob not adjusted to cover
b. Adjust knob. Para 3-7a and g.
a minimum span of +4.00 to
a. Defective contact or loose wire.
a. Check wire connection or replace
Reticle lamps fail to illuminate.
b. Lack of electrical power to reticle
b. Check electrical input into recep-
tacle assembly (9, fig. 3-11).
c. Lamps burned out.
d. Loose wire connections or defective
d. Check connection to receptacle as-
sembly (9, fig. 3-11) or replace.
Telescope or reticle projector will not
Dirt preventing valve from closing or
Clean or replace valve stem. Para 3-6.
hold nitrogen charge.
a. Gear teeth on filter assembly housing
a. Replace filter assembly (10, fig. 3-12).
Filters not fully positioned in optical path
when viewed through eyepiece
b. Operating mechanism not adjusted
b. Reposition gear (12, fig. 3-12) to
mesh with gear at rear of the
filter assembly housing. Operate
handle to turn filter assembly to
extreme position in both directions
and adjust stops (set-screws) (1,
Excessive parallax between target and
Use parallax adjustment screw (5, fig. 3-
Section III. GENERAL MAINTENANCE
2-5. General Maintenance Procedures
Grease, Aircraft and Instrument
Gear and Actuator Screw
Refer to TM 9-254.
Grease, Pneumatic Systems
Sealing Compound (Adhesive Cur-
2-6. Other Materials Required
Sealing Compound (Noncuring)
The following materials are used to perform repair
functions described in this manual.