TM-9-1240-401-34&P Technical Manual for M109 Telescopes and Mounts Download
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TM9-1240-401-34&P MALFUNCTION TEST OR INSPECTION LOCATION CORRECTIVE ACTION CROSS-LEVEL MECHANISM 2. CROSS-LEVEL MECHANISM KNOB(2) IS ERRATIC AND ROUGH DURING MOVEMENT. Check for worn wormshaft. Replace wormshaft assembly (ref. para 4-13). 3. CROSS-LEVEL MECHANISM KNOB (2) EXCEEDS 0.5 MIL BACKLASH. Step 1. Check for worn bearings. Replace wormshaft assembly (ref. para 4-13). Step 2. Check for worn or bent wormshaft. Replace wormshaft assembly (ref. para 4-13). 4. CROSS-LEVEL MECHANISM KNOB (2) REQUIRES TORQUE IN EXCESS OF 11 POUND-INCHES (1 .24 N-M) TO ROTATE. Check for worn or bent wormshaft and/or bearings. Replace wormshaft assembly (ref. para 4-13). LEVEL ASSEMBLY 5. NO ILLUMINATION IN CROSS-LEVEL (3) OR PITCH LEVEL (4). Observe visually. a. Replace burned out LEDs (ref. para 4-15). b. Replace defective toggle switch (ref. para 4-15). c. Clean or replace defective lens cap (ref. para 4-15). 4-7