TM-9-1240-401-34-P

TELESCOPE MOUNT M146: M118A2 AND M118A3; TELESCOPE MOUNT M145: M145A1; PANORAMIC TELESCOPE: M117 AND M117A2; FIRE CONTROL QUADRANT: M15; PERISCOPE: M42

TECHNICAL MANUAL; DIRECT SUPPORT AND GENERAL SUPPORT MAINTENANCE MANUAL

JULY 1993

TM-9-1240-401-34-P - Page 228 of 590

5-54

TM 9-1240-401-34&P

5-26. M117/M117A2 PANORAMIC TELESCOPE FINAL INSPECTION AND ADJUSTMENT

- continued

I

g. PARALLELISM OF RETICLE AND IMAGE

1 Rotate azimuth knob (1) until reticle line of

M117/M117A2 panoramic telescope (2) coincides

with reticle line of collimating projector (3).

2 Check image tilt through two full revolutions of the

cap assembly. The image of a vertical target line

shall be vertical within 0.62 mils or 2° of arc over

the full field of view of the dioptometer (4).

h. PLUMB TRAVEL AND LINE OF SIGHT TRAVEL

1 Collimate M117/M117A2 panoramic telescope (ref.

para 5-26c).

2 Suspend plumb line (1) to one side of azimuth test-

ing fixture (2).

3 Rotate azimuth knob (3) to sight onto plumb line

(1).

4 Install a parallax shield on M117/M117A2 pano-

ramic telescope eyepiece (4).

5 Place a mark on wall behind plumb line (1), inter-

secting reticle line.