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 246 of 590

TM 9-1240-401-34&P

5.1-10. DIRECT SUPPORT TROUBLESHOOTING - continued

MALFUNCTION

TEST OR INSPECTION

LOCATION

CORRECTIVE ACTION

COVER ASSEMBLY - continued

4.

COUNTER WINDOWS (3) ARE FOGGED OR HAVE

CONDENSATION.

Check for damaged glass and defective or missing parts.

a.

Replace glass if required (ref. para 5.1-16).

b.

Replace defective or missing parts as

required and authorized (ref. para 5.1-16).

c.

Remove cover assembly. Wipe dry, then

purge and charge M15 quadrant with dry

nitrogen after reinstalling cover (ref. TM 750-

116).

CORRECTION KNOB ASSEMBLY

5.

CORRECTION KNOB (4) BINDS.

Check for defective correction knob assembly.

a.

Repair correction knob assembly (ref. para

5.1-15).

b.

If correction knob still binds, notify general

support maintenance.

COUNTER ASSEMBLY

6.

CORRECTION COUNTER FAILS TO ALLOW +50 MILS MIN

OR -50 MILS MIN.

Step 1.

Check for incorrect assembly of key washers

after repair.

Reinstall key washers correctly (ref. para

5.1-15).

Step 2.

Check for worn or damaged correction knob

assembly.

Replace worn or damaged parts as required (ref.

para 5.1-15).

5.1-12

Change 1