SQUELCH SWITCH AND FREQUENCY SELECTION TEST.

TM 11-5820-670-30

2-21. SQUELCH SWITCH AND FREQUENCY SELECTION TEST.

PURPOSE

This test checks for proper operation of the control unit's squelch functions. The test also includes a

check of the calibration between the control unit frequency selectors and gearbox assembly

indicators.

TEST EQUIPMENT AND MATERIALS

Maintenance Kit MK-1035/ARC-131

Receiver-Transmitter, Radio RT-823/ARC-131

Antenna Coupler Simulator SM-499/ARC-131

Power Supply PP-2953/U

All cables ore part of MK-1035/ARC

TEST SETUP

Connect equipment as shown in test setup diagram. Replace control unit in test set with control unit

under test. Turn on all equipment and allow at least 5 minutes for warmup.

EL1AT156

INITIAL EQUIPMENT CONTROL SETTINGS

Set equipment controls as indicated in the following table.

CONTROL AND SWITCH SETTINGS

POSITION/SETTING

CONTROL OR SWITCH

EQUIPMENT

TS-2575/ARC-131

+28 VDC ON-OFF switch

TRANSMIT switch

OFF

MODE SWITCH

T/R

C-7088/ARC-131

FREQ sel

30.95 MHz

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