C-7066/ARC-131 MODE SWITCH SELECTION AND FRONT PANEL ILLUMINATION TEST.

TM 11-5820-670-30

2-19. HOMING SENSITIVITY TEST. (CONT)

TEST PROCEDURE (CONT)

12. Adjust AN/URM-103 for zero input to the radio set.

STANDARD. Horizontal needle should be near bottom of homing indicator lD-48/ARN.

13. If horizontal needle is not near bottom of indicator, see troubleshooting chart 2-23.

14. Set test set FREQ sel for 31.00 MHz and LEFT and RIGHT HOMER ATTEN controls to 0.

15. Set AN/URM-103 DEVIATION RANGE KHZ switch to 10 and adjust DEVIATION control for 8 kHz

deviation.

16. Adjust AN/URM-103 ATTENUATOR control for a 300 microvolt output signal.

STANDARD. Horizontal needle should be on first dot below center of homing indicator.

17. If horizontal needle is not as described in standard, see troubleshooting chart 2-23.

18. Adjust AN/URM-103 ATTENUATOR control for a 20,000 microvolt output signal.

STANDARD. Horizontal needle should be on first dot below center of homing indicator.

19. If horizontal needle is not as described in standard, see troubleshooting chart 2-23.

20. Repeat steps 16 through 19 adjusting the frequency selectors of the test set for frequencies of

50.50 MHz and 68.95 MHz.

2-20. C-7066/ARC-131 MODE SWITCH SELECTION AND FRONT PANEL ILLUMINATION TEST.

PURPOSE

This test checks for proper operation of the control unit mode switch and front panel lamp indicators.

TEST EQUIPMENT AND MATERIALS

Maintenance Kit MK-1035/ARC-131

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

Power Supply PP-2953/U

All cables are part of MK-1035/ARC

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