ARMY TM 9-1290-262-24&P
MARINE CORPS TM 00476C-24&P
AIR FORCE TO 49A7-3-72/74
PARALLAX OF MAGNIFIER ASSEMBLY
1
Turn aiming circle so that the letter N on
the aiming circle body is pointing in the
general direction of north.
Place hand light (1) from M51 instrument
2
light over the housing cover window. Light
should illuminate damper and needle reti-
cle.
Look into dioptometer (2) eyepiece and
3
turn eyepiece until reticle is in sharpest
focus.
Hold dioptometer (2) against magnifier (3).
4
Unlock compass needle. Rotate aiming
5
circle azimuth knob (4) until etched line on
compass needle is next to, but not touch-
ing, dioptometer reticle.
Slide dioptometer knob (5) for sharpest
6
focus of compass needle etching. Diop-
tometer scale reading should be between
0 and -0.50.
Screw magnifier assembly in or out, as
7
required.
Repeat step 3 and check parallax. It must
8
not exceed 1 mil (one reticle line width).
Seal magnifier assembly by injecting seal-
9
ing compound (item 8, appx D) into the
two injection sealing ports. See TM 750-
116.
