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 296 of 590

TM 9-1240-401-34&P

5.1-24. M15 QUADRANT FINAL INSPECTION AND ADJUSTMENT - continued

a.

SETTING UP AND ADJUSTING CROSS-LEVELING FIXTURE - continued

10

11

12

13

14

15

Remove centering plug (11) from round block (8).

Using known good gunner’s quadrant and 6-inch

parallel bar positioned across the top of two straight

keys (12), ensure that keys are parallel with flat

surface of round block (8).

Recheck square portion of elevation shaft (3) to

ensure that shaft is still level in elevation and cross-

level positions. If not, repeat step 8.

Using known good gunner’s quadrant and 6-inch

parallel bar, position parallel bar and gunner’s

quadrant on the face of round block (8)

perpendicular to flat surface of round block (8), and

adjust two cap screws (7) at 12 o’clock position and

two cap screws (7) at 6 o’clock position until bubble

on gunner's quadrant is centered.

Rotate upper section handwheel (elevation) (9) to

position flat surface of round block (8) from

horizontal to perpendicular position as measured

with a known good gunner’s quadrant and a 6-inch

parallel bar on flat surface of round block (8).

Position 6-inch parallel bar against two keys (12).

Using known good gunner's quadrant placed on

parallel bar, adjust two cap screws (7) at the 6

o’clock position until bubble in gunner's quadrant is

centered.

Repeat steps 7 thru 12 until test fixture adapter (6)

and square portion of elevation shaft (3) are in

agreement.

5.1-62

Change 1