Section III ORGANIZATIONAL PREVENTIVE MAINTENANCE CHECKS AND SERVICES (PMCS)

TM 11-5820-670-12

INSTALLATION INSTRUCTIONS. (CONT)

3-4.

Turn SQ ADJ control (4) on receiver-transmitter (5) fully counterclockwise.

Set VOL control (6) on control unit (2) so that the background noise can be heard at a com-

fortable level in the headset.

Slowly rotate receiver-transmitter SQ ADJ control (4) clockwise until background noise just cuts

out. Do not rotate SQ ADJ control beyond this cut out point.

Check squelch setting at high, midrange, and low frequencies. If any of the frequencies are

not fully squelched, rotate SQ ADJ control (4) slightly clockwise.

Turn off all communications equipment in accordance with stopping procedures (para 2-4).

10.

Reconnect communications antenna coaxial cable disconnected in step 1.

Perform complete preflight operational check (para 2-3).

11.

Section Ill ORGANIZATIONAL PREVENTIVE MAINTENANCE CHECKS AND

SERVICES (PMCS)

Page

Para

Subject

General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5

Organizational Preventive Maintenance Checks and Services . . . . . . . . . . . . . . . . . 3-6

Cleaning and Touchup Painting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . 3-7

3-5. GENERAL.

To ensure that Radio Set AN/ARC-131 is in proper operating condition at all times, it must be in-

spected and checked systematically so that any defect or damage which may have occurred can be

found and corrected to prevent any permanent damage or radio set failure. These inspections and

checks are termed preventive maintenance checks and services (PMCS). Defects discovered during

operation of the radio set shall be noted and corrected as soon as operation has ceased. Stop

operation immediately if a deficiency is noted during operation which can damage equipment.

NOTE

Record all deficiencies together with corrective action in accordance with procedures

outlined in DA Pam 738-750.

Organizational PMCS consist of intermediate PMCS and periodic PMCS.

3-9