VOLUME CONTROL TEST. - TM-11-5820-401-34-30088

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

GENERAL. (CONT)

3-1.

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.

3-2. 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 receiver 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

Matching Unit CN-901/U

Power Supply PP-1104(*)/G

Loudspeaker LS-454/U

Frequency Counter AN/USM-207

Maintenance Kit MK-1978/VRC

Signal Generator AN/URM-103

Rf Cables (two) RG-58/U

Adapter (T-Connector) UG-274 B/U

TEST SETUP. Connect equipment as shown in test setup diagram

3-2