TM-9-1240-400-34&P Technical Manual for M109 Telescopes and Mounts Download
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TM 9-1240-400-34&P VISUAL INSPECTION 1 Check that all screws are present. 2 Check that mounting surface (1) is clean and free of nicks and burrs. 3 Check that M139 elbow telescope (2) is free of dirt and foreign matter, that all parts are present, and that paint is not chipped. 4 Look through eyepiece assembly (3) and check that there is no dirt or moisture on lenses (4) and reticle assembly (5). 5 Look through optical instrument cell assembly (6) and check that no dirt or moisture is present on lens (7) or optical instrument prism (8). EYEPIECE ASSEMBLY FOCUS INSPECTION AND ADJUSTMENT 1 Position M139 elbow telescope on flat surface. 2 Focus dioptometer eyepiece (1) until reticle is sharp. 3 Set dioptometer range scale (2) at minus 0.75 to minus 1.0. 3-19