Audio Response Test (Normal Mode) at 1 kHz

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

3-8. RECEIVER AUDIO RESPONSE TEST (NORMAL MODE). (CONT)

3. Set AN/USM-207 controls to following positions:

CONTROL/SWITCH

POSITION/SETTING

POWER

TRACK

DISPLAY

MIN (fully counterclockwise)

0.1 v

SENSITIVITY

1 (black knob)

GATE TIME

FREQ

FUNCTION

4. Disconnect rf cable from Adapter UG-514. (See test setup diagram

Page 3-22.)

5. Connect rf cable to AN/USM-207 FREQ A connector.

6. Adjust AN/URM-127 FREQ RANGE DIAL for 1-kHz display on AN/USM-207.

Disconnect rf cable from AN/USM-207 FREQ A connector.

8. Reconnect rf cable to Adapter UG-514.

9. Connect ME-30(*)/U INPUT lead A to MK-1978/VRC SPKR jack; connect lead B to GND jack.

10. Adjust R-442/VRC VOLUME control for 17-volt indication on ME-30(*)/U. Do not change

VOLUME control position during rest of test.

STANDARD. A 1-kHz modulating tone injected into the R-442/VRC should produce 17 volts at the

output.

11. If R-442/VRC VOLUME control adjustment cannot produce 17-volt indication on ME-30(*)/U,

see troubleshooting chart 3-10.

Audio Response Test (Normal Mode) at 500 Hz

12.

Turn AN/URM-127 FREQ RANGE DIAL to 50.

13.

Disconnect rf cable from Adapter UG-514. (See test setup diagram

14.

Connect rf cable to AN/USM-207 FREQ A connector.

15.

Adjust AN/URM-127 FREQ RANGE DIAL for 500-Hz display on AN/USM-207.

16.

Disconnect rf cable from AN/USM-207 FREQ A connector.

17.

Reconnect rf cable to Adapter UG-514.

STANDARD. ME-30(*)/U should indicate between 14 and 22 volts.

18. If ME-30(*)/U indicates below 14 volts or above 22 volts, see troubleshooting chart 3-5.

Audio Response Test (Normal Mode) at 3 kHz

19.

Switch AN/URM-127 FREQ RANGE MULTIPLIER to x100.

20.

Turn FREQ RANGE DIAL to 30.

21.

Disconnect rf cable from Adapter UG-514. (See test setup diagram

22.

Connect rf cable to AN/USM-207 FREQ A connector.

23.

Adjust AN/URM-127 FREQ RANGE DIAL for 3-kHz display on AN/USM-207.

24.

Disconnect rf cable from FREQ A connector.

25.

Reconnect rf cable to Adapter UG-514.

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