Table 3-2. Troubleshooting

TM 11-6625-2609-34

Table 3-2. Troubleshooting--Continued

Malfunction

Corrective action

Probable cause

e. Contacts of radio control switches c. Clean contacts or replace switch

S1 and S2 wafers. -

S1 and S2 dirty or broken.

5. No output at DATA LINK OUT- Open or shorted wiring from W1P2A- Check and correct wiring.

PUT jacks with proper 132.500-

15 and W1P2A-16 to test panel

MHz signal to AN/ARC-134.

jacks J16 and J17.

6. No output at RECEIVER jack with a. AUDIO switch is at OFF . . . . . . a. Set AUDIO switch to ON.

b. EXTERNAL SQUELCH switch at b. Set

EXTERNAL

SQUELCH

proper signal to AN/ARC-134.

switch to OFF, or readjust

ON.

EXT. SQUELCH CONTROL.

c. Radio control potentiometer RI c. Replace R1.

open.

d. Open or shorted wiring from con- d. Check and correct wiring.

nector Pib and Pi-d to test

panel jack J4.

7. No output at RECEIVER jack when a. EXT. SQUELCH CONTROL mis- a. Readjust EXT. SQUELCH CON-

adjusted.

TROL.

COMM TEST switch is depressed.

b. Radio Control switch S3 defec- b. Replace switch S3.

tive.

c. Open or shorted wiring from P1- c. Check and correct wiring,

g and P1-h to W1P2B-30 and

W1P2B-31.

8. EXT. SQUELCH CONTROL has no a. EXTERNAL SQUELCH switch at a. Set

EXTERNAL

SQUELCH

switch to ,ON.

effect on level at which squelch

OFF.

b. Test panel potentiometer R1 de- b. Replace R1.

breaks.

fective.

c. Open or shorted wiring between c. Check and correct wiring.

RI and W1P2B-37, W1P2B-38,

and W1P2B-39.

9. No output from AN/ARC-134 at a. PTT switch is at OFF . . . . . . . . . . a. Set PTT switch to ON.

b. Open or shorted wire between b. Check and correct wiring.

antenna connector W1P3.

switch S1 and W1P2A-31.

10. No output at SIDETONE jack . . . . a. Open or shorted wiring between a. Check and correct wiring.

J5 and W1P2B-28 and W1P2B-

29.

b. Open or shorted wiring between b. Check and correct wiring.

W1P2A-31

and P4-35 or

W1P2A-30 and P4-26.

I n t e r c o m control defective

Repair or replace intercom control.

d. U-94A/U defective . . . . . . . . . . . . .

Repair or replace U-94A/U.

11. No evidence of modulation with Gen- Open or shorted wire between J18 Check and correct wiring.

and W1P2A-30, or between J19 and

erator, Signal AN/URM-127 sup-

ground.

plying signal to MIKE INPUT

jacks.

12, No output at DETECTOR METER Defective detector circuit . . . . . . . . . . . Repair or replace detector circuit.

jacks with antenna connector

W1P3 connected to DET INPUT

jack.

Table. 3-3. Resistance and Continuing Tests

Isolating procedure

Point of measurements

Normal indication

Between tip contact of test panel jack Short circuit . . . . . . . . . . . . . . . . . . . . . . Check wiring from J22 to W1P2A-31.

J22 and W1P2A-31.

Between ring contact of test panel jack Short circuit . . . . . . . . . . . . . . . . . . . . . . Check wiring from J22 to W1P2A-30.

J22 and W1P2A-30.

With PTT switch at ON, between sleeve Short circuit . . . . . . . . . . . . . . . . . . . . . .

Check test panel switch S1 and wir-

contact of test panel jack J22 and

ing from J22 sleeve contact to

W1P2A-31.

w1P2A-31.

Between test panel jack J18 and Short circuit . . . . . . . . . . . . . . . . .

Check wiring between J18 and

W1P2A-30.

3-3