TM-9-1240-401-34&P Technical Manual for M109 Telescopes and Mounts Download
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TM 9-1240-401-34&P Item No. 4 5 Item To Be Inspected ELEVATION KNOB (4) AND ELEVATION MECHANISM - CONTINUED CROSS-LEVEL KNOB (5) AND CROSS LEVEL MECHANISM Procedures b. c. a. b. c. Check elevation travel by turning elevation knob clockwise to stop. Center elevation level vial bubble by turning handwheel on upper section of cross-leveling fixture. Check that scale on upper section of cross-leveling fixture reads at least 77° 47’ 37.5”. Turn elevation knob counterclockwise to stop and center elevation level vial bubble. Check that upper scale reads at least 12° 49’ 30”. Check backlash by turning elevation knob clockwise to center elevation level vial bubble. Turn counterclockwise past center and then back to original position. Check that level vial bubble centers again within 1/2 space between level vial graduations. Check that torque required to turn elevation knob in either direction does not exceed 8 pound-inches (0.904 N-m) at any point between stops. Check cross-level travel by turning cross-level knob to either stop. Turn handwheel on lower section of cross-leveling fixture to center cross-level vial bubble. Check that scale on lower section of cross-leveling fixture reads at least 34°. With cross-level vial bubble centered, turn cross-level knob clockwise. Then turn back to original position to check backlash. Check that cross-level vial bubble centers within 1/2 space between level vial graduations. Change 1 5.1-7