Section I PERFORMANCE TESTS

TM 11-5820-401-34-3/0967- LP-432-3060

Section I PERFORMANCE TESTS

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Subject

General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

VOLUME Control Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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Receiver Sensitivity Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

NEW SQUELCH Test.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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OLDSQUELCHTest . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Receiver Audio Power Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Receiver Audio Distortion Test . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . .. . . . . ..

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Receiver Audio ResponseTest (Normal Mode) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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ReceiverAudio ResponseTest (X-Mode) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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Receiver Selectivity Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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4-1.

GENERAL.

This section contains performance test procedures for use with Test Set AN/GRM-114A. They will

enable you to determine whether or not an R-442/VRC is operating acceptably. Each test procedure

checks specific functions of the receiver to help you find and isolate faults.

Each test is complete and may be performed individually. Therefore, you may choose the appropriate

test to verify gross equipment failure or performance degradation of specific stages. However, this

maintenance approach is not recommended. It is best to perform all the tests in sequence. This

systematic maintenance approach will ensure that all faults are found and corrected.

Faults in the R-442/VRC are evidenced by failure of the radio to meet the performance standards found

within the test procedures in bold type. When an R-442/VRC fails to meet a performance standard,

discontinue the test and turn to the troubleshooting chart referred to in the procedure.

4-2. VOLUME CONTROL TEST.

PURPOSE. This test checks the VOLUME control of the R-442/VRC for proper operation. When a

1-kHz tone is injected into the R-442/VRC ANTENNA port, the speaker should output a clear tone with

no scratchy sound or sudden drop in volume. The absence of a tone means that the signal is not

passing completely through the R-442/VRC circuitry and could even indicate total equipment failure;

therefore, perform this test before the others in this section.

TEST EQUIPMENT AND MATERIALS

Power Supply PP-1104(*)/G

Test Set AN/GRM-114A

Maintenance Kit MK-1978/VRC

Rf Cable RG-58/U

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