NEW SQUELCH Test at Other Frequencies

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

4-4. NEW SQUELCH TEST. (CONT)

2. If CALL lamp does not light, set AN/GRM-114A MODULATION FREQ Hz thumbwheels (2) to

00151.0 Hz, return RF LEVEL control (1) to minimum setting, and repeat step 1. If CALL

lamp still does not light, set MODULATION FREQ Hz thumbwheels (2) to 00149.0, return

RF LEVEL control (1) to minimum setting, and repeat step 1.

STANDARD. R-442/VRC CALL lamp should light while AN/GRM-114A RF LEVEL is at or below

0.5 v.

3. If RF LEVEL (1) is more than 0.5 v when R-442/VRC CALL lamp lights or if CALL lamp will

not light, see troubleshooting chart 4-5.

4. Remove cable from R-442/VRC ANTENNA port.

STANDARD. R-442/VRC CALL lamp should go out. Remember, without the 150-Hz tone, Relay

K5002 will not be energized to supply the 16 volts necessary to turn on the audio amplifiers; therefore,

the receiver is squelched.

5. If CALL lamp does not go out, see troubleshooting chart 4-5.

6. Reconnect cable to R-442/VRC ANTENNA port.

STANDARD. R-442/VRC CALL lamp should light,

7. If CALL lamp does not light, see troubleshooting chart 4-5.

NEW SQUELCH Test at Other Frequencies

8. Return AN/GRM-114A RF LEVEL control (1) to minimum setting.

9. Set AN/GRM-114A RF FREQUENCY MHz thumbwheels (3) and R-442/VRC MC-TUNE-KC switch

to frequency control settings listed below. Repeat steps 1 through 7 at each frequency.

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