TM-9-1240-400-34&P Technical Manual for M109 Telescopes and Mounts Download

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TM 9-1240-400-34&P 2-17. M115 PANORAMIC TELESCOPE FINAL INSPECTION INSTRUCTIONS (CONT). DEFLECTION ERRORS (800 MIL STEPS) AND BACKLASH (DEFLECTION MECHANISM) INSPECTIONS 1 Rotate deflection knob (1) until head assembly (2) makes 2 full revolutions. NOTE Deflection error and backlash combined must not exceed 1.5 mil between positive and negative error. Total error, excluding backlash, between deflection counter (3) and reset counter (4) reading, for any one number, must not exceed 0.5 mil. • Backlash in deflection mechanism must not exceed 1.0 mil when read on azimuth counter (5) and 1.25 mils on reset counter (4). 2 Collimate telescope. Refer to page 2-69. 2-72