TM-9-1240-401-34&P Technical Manual for M109 Telescopes and Mounts Download
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5-57 TM 9-1240-401-34&P j. LEVEL TRAVEL AND LIFT 1 2 3 4 5 6 7 8 9 10 11 Set azimuth fixture ring (1) to "0" coincidence on azimuth testing fixture (2). While sighting through M117/M117/A2 panoramic telescope eyepiece (3), rotate azimuth knob (4) and elevation knob (5), until M117/M117A2 pano- ramic telescope reticle coincides with reticle of collimating projector (6). Rotate azimuth fixture ring (1) 800 roils counter- clockwise Rotate azimuth knob (4) clockwise until retitles coincide. Check that line of sight does not deviate from hori- zontal by more than 6.0 mil. Rotate azimuth knob (4) clockwise approximately one-half revolution while observing reticle. Rotate azimuth knob (4) slowly counterclockwise until retitles coincide. Check that line of sight changes no more than 0.5 mil from reading in step 5. Repeat steps 3 thru 8 until azimuth fixture ring (1) has made two full revolutions. During level travel test, direction of cap rotation shall be reversed. Any vertical displacement of line of sight with respect to horizontal target line result- ing from this reversing of travel shall not exceed 2.0 mil. This test shall be performed at minimum of eight 800-mil azimuth settings. If level travel exceeds tolerance specified, check mounting surfaces of M117/M117A2 panoramic telescope (7) and fixture adapter (8) for dirt and burrs. If none of above conditions exist, return M117/M117A2 panoramic telescope to depot main- tenance.