TM-9-1240-400-34&P Technical Manual for M109 Telescopes and Mounts Download
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TM 9-1240-400-34&P IMAGE TILT ADJUSTMENT 1 Suspend plumbline in front of projector collimator (1). 2 Install dioptometer (2) in telescope holder (3) and adjust so dioptometer faces eyeshield (4). 3 Install a parallax shield on eyeshield (4). 4 Sight through dioptometer (2), directly on to plumbline and revolve dioptometer, in telescope holder (3), until vertical line is superimposed on plumbline and secure telescope holder. 5 Position dioptometer (2) directly in front of eyeshield (4). 6 Image of vertical line must be within 1 degree (17.78 mils) as seen through dioptometer (2) and as measured on test reticle projector collimator (1). 7 If required measurement cannot be met, remove four screws (5), four lockwashers (6), access cover (7), and gasket (8) to gain access to optic cell assembly (9). 8 Remove setscrew (10) from plug hole next to access cover (8) to gain access to three setscrews (11). 2-65