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). PARALLAX ADJUSTMENT 1 Check for allowable parallax of 0.15 mil using preset target of 130 meters + 10 meters. If parallax exceeds limit, go to step 2. 2 Remove three setscrews (1) and head assembly (2), rotating head assembly counterclockwise. 3 Scribe a coinciding line on worm gear assembly (3) from cover (4). 4 Rotate deflection knob (5) to gain access to setscrew (6) through cover (4). 5 Remove setscrew (6) and turn objective cell (7) a small amount in either direction. 6 Temporarily install head assembly (2) and observe parallax. Adjust objective cell as required. 7 Apply sealing compound (item 10, appx C) to threads of setscrews (6). 8 Aline scribe marks on cover (4) and worm gear assembly (3) and install setscrew (6). 9 Install head assembly (2). 10 Using torque wrench and torque adapter (figure 4, appx D), tighten head assembly (2) to 80.00 in.-lb (9.04 N-m). 11 Apply sealing compound (item 10, appx C) to threads of three setscrews (1). 12 Install three setscrews (1). 2-64