TM 9-1290-357-15
(10) Eyepiece focusing sleeve movement will
4-18. Modification Work Orders (MWO)
function without undue irregularities, friction,
All applicable modification work orders will be
or looseness.
applied. Check DA Pamphlet 310-7, for applicable
(11) Telescope elevating mechanism shall
modification work orders.
not bind when elevating or depressing, and the
stop mechanism will restrain the telescope body
4-19. General Inspection
from striking the magnetic needle window.
a. Aiming Circle M1.
(12) Azimuth worm movement will function
(1) Check the aiming circle carefully for
without undue irregularities, friction or looseness,
completeness to be sure all components and as-
and the azimuth worm release mechanism will
sociated equipment are present.
function to return the worm into mesh imme-
diately upon releasing.
(2) Looking through the eyepiece and ob-
jective ends of the telescope assembly there will
(13) Orienting worm movement will function
be no objectionable dirt, smears, scratches, digs,
without undue irregularities, friction or loose-
condensate, fungus growth, chips, fractures, or
ness.
cement separations.
Note. Orienting worm movement will be considerably
tighter than azimuth worm movement.
Note. Optical instruments will not be rejected for de-
fects which can only be detected by the shading or shadow-
(14) Scales, graduations, and their indexes
ing technique. When inspecting through the eyepiece end
shall be clearly legible.
of the telescope assembly, rejection is to be based only on
those defects which are apparent when field conditions
(15) Orienting clamping screw shall clamp
exist. "Shadowing" is the technique of looking into the
aiming circle to the vertical spindle of the tripod.
eyepiece or objective end of the instrument obliquely so as
to obtain reflections from a particular surface in the
(16) Exterior surfaces of the instrument shall
optical system. With this method, the surfaces of lenses
be free from corrosion, rust, chipped or loose
and retitles are dark gray in appearance and all defects
paint and other objectionable matter.
(condensate, scratches, etc.) show up as white particles.
(17) Sealing of the telescope body and mag-
(3) Looking through the magnetic needle
netic needle window shall not be deteriorated
magnifier there will be no objectionable dirt,
which may cause apparent leaks or openings.
smears, scratches, etc. or foreign matter.
b. Tripod M5.
(4) Magnetic needle magnifier assembly will
(1) Tripod's vertical spindle shall be free
be securely sealed and fastened to the aiming
of burrs or other foreign matter that would inter-
circle body.
fere with the proper seating of the aiming circle.
(5) Check that magnetic needle window is
(2) When the aiming circle is mounted on
free from breaks, cracks, chips, or any other for-
the tripod, the ball and socket clamp shall oper-
eign matter.
ate to lock tripod's vertical tube at any desired
(6) Silver plating on the interior surfaces
height.
of the aiming circle body will be in good condition
(3) Tripod telescoping legs shall have a
having no appreciable peeling or deterioration.
smooth movement when adjusting legs up or down
(7) Magnetic needle locking and release me-
and hold their position when clamped in position.
chanism which is operated by the red (locking)
(4) Tripod surfaces will be free of corro-
and olive drab (releasing) buttons will function
sion, chipped or loose paint, or any other ob-
properly for locking and releasing of the magne-
jectionable matter which may hamper or cause
tic needle. Needle will operate freely when in
tripod to operate inefficiently or not at all.
the released position.
c. Instrument Light M2. Check instrument
(8) Telescope body level vial and circular
light for completeness, operation of switch and
level vial will be free from cracks, and securely
lamp, and condition of wiring. Check case hous-
mounted.
ing and parts to determine that they are not dent-
(9) Reticle illuminating window will not be
ed, bent or twisted. Metal components shall be
broken and will be securely sealed and fastened
free of corrosion, rust, loose paint, or other ob-
in the body of the telescope assembly. Instrument
jectionable material.
light dovetail slot will be free from nicks, burrs
d. Aiming Circle Cover M409. Check that the
or paint.
