RECEIVER SENSITIVITY, QUIETING, AND LIMITING TEST.

TM 11-5820-670-30

2-6. AUDIOFREQUENCY RESPONSE AND FRONT PANEL METER TEST. (CONT)

10. Observe audio output change in db from the 1000 Hz reference (step 2).

STANDARD. + 2 db -3 db

11. If audio output change is not within + 2 db to -3 db, see troubleshooting chart 2-8.

12. Disconnect cable CG-3371/U (W7) from WIDEBAND J108 and reconnect to NORMAL J107 on

test set.

13. Repeat steps 1 and 2.

14. Rotate TEST switch on front panel of RT-823/ARC-131 and verify the following TEST METER

indications.

PERFORMANCE STANDARD

TEST SWITCH

TEST METER

POSITION

INDICATION

50 20

not less than 70

2-7. RECEIVER SENSITIVITY, QUIETING, AND LIMITING TEST.

PURPOSE

This test checks the ability of the rt to detect low level rf signals at several frequencies. Low level rf

contains noise and distortion which make hearing the audio signal difficult.

TEST EQUIPMENT AND MATERIALS

Maintenance Kit MK-1035/ARC-131

Signal Generator AN/URM-103

Signal Generator AN/URM-127

Spectrum Analyzer TS-723A/U

Power Supply PP-2953/U

All cables are part of MK-1035/ARC

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