TM-9-1290-262-24&P Technical Manual for M2A2 Aiming Circle Download
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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 2 3 4 5 6 7 8 9 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 light over the housing cover window. Light should illuminate damper and needle reti- cle. Look into dioptometer (2) eyepiece and turn eyepiece until reticle is in sharpest focus. Hold dioptometer (2) against magnifier (3). Unlock compass needle. Rotate aiming 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 focus of compass needle etching. Diop- tometer scale reading should be between 0 and -0.50. Screw magnifier assembly in or out, as required. Repeat step 3 and check parallax. It must not exceed 1 mil (one reticle line width). Seal magnifier assembly by injecting seal- ing compound (item 8, appx D) into the two injection sealing ports. See TM 750- 116. 4-25