TM-9-1290-262-24&P Technical Manual for M2A2 Aiming Circle Download
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ARMY TM 9-1290-262-24&P MARINE CORPS TM 00476C-24&P AIR FORCE TO 49A7-3-72/74 3-7. TEST AND ADJUSTMENT PROCEDURES (cont). MAGNETIC NEEDLE REPEATABILITY TEST 1 2 3 4 5 6 7 8 9 10 Rotate aiming circle so that N on housing faces in the general direction of north. Unlock magnetic needle. Look through magnifier (1) and turn aiming circle to aline end of needle with edge of a reticle line. Hold steel block (2) close enough to aim- ing circle to deflect magnetic needle to one side as far as it will go. Look through magnifier (1), then remove steel block (2). Observe and note needle position relative to reticle line after needle has come to rest. Hold steel block (2) close enough to aim- ing circle to deflect magnetic needle to other side as far as it will go. Look through magnifier (1), then remove steel block (2). Observe and note needle position relative to reticle line after needle has come to rest. In steps 6 and 9, needle should return to its original position within 0.5 mil (the ap- proximate width of a reticle line). If needle does not return to its original position with- in 0.5 mil, notify next higher maintenance level. 3-46