Sytem Troubleshoot the Intercommunication Set AN/VIC-1(V) with Medium
Power FM Radio and COMSEC Equipment
Objective - ss0728a0010
The circuits have been color coded
Operation Check
Figure 1. DC source voltage from vehicle communication power Bendix jack through MT-1029.
Figure 2. Mount MT-1029 configurations.
Figure 3. DC voltage path from pin B of J22 to AM-1780.
Figure 4. Intercom input power circuit.
Figure 5. Intercom keying circuit operating voltage (+24 volts DC).
Figure 6.Commander's intercom keying circuit (intercom keyed).
Figure 7. Intercom keying circuit (crew member and driver).
Figure 8. Talk circuit through C-2298 from J802 or J803.
Figure 9. Commander's voice signal path with MONITOR switch set to ALL, A, INT ONLY, or B.
Figure 10. Commander's voice signal, MONITOR switch set to C.
Figure 11. Crew voice signal MONITOR switch set to ALL, A, INT ONLY, or B.
Intercom listen circuit.
Figure 14. Listen signal to MONITOR switch.
Figure 16. Listen circuit (AC signal) from MONITOR switch through volume control to pins B and E of J802 or J803.
Figure 17. Intercom listen circuit.
Figure 18. Intercom input power problem listed on DA Form 2404.
Possible bad equipment. - ss0728a0029
Test procedure 1.
Test procedure 2.
Test procedure 3.
Test procedure 4.
Test procedure 5
Test procedure 6
Test procedure 7
Figure 27. Symptom observed when performing EPC step 1d.
Possible bad equipment. - ss0728a0038
General test procedures. - ss0728a0039
Test procedure 8
Test procedure 9
Test procedure 11.
Test procedure 13
Figure 33. No intercom keying, EPC step 2.
Figure 34. CDR intercom keying circuit.
Test procedure 14
Test procedure 15
Figure 37. Continuous intercom keying, EPC step 2.
Figure 38. Commander's intercom keying circuit, continuous keying.
No sidetone.
Figure 40. Talk/listen circuit.
Test procedure 18
Remote power circuit.
Return power circuit.
Figure 43. Return power to the J-3513 and KY-57.
Figure 44. Return power to R-442.
Figure 45. Return power to J-3514 and KY-57.
Input power.
Figure 47. A-RT dial lamp and AM-1780 power lamp do not light (possible bad items).
General test procedures. - ss0728a0060
Test procedure 22
Figure 49. Return power circuit (possible bad items).
General test procedures. - ss0728a0063
Figure 50. Return power circuit test points.
TSEC/KY-57 Input Power Circuit
Test procedure 28
Figure 52. KY-57 input power circuit: test points.
R-442 remote power control
General test procedures. - ss0728a0069
Figure 54. R-442 remote power control circuit (test points).
TSEC/KY-57 no input power
Test procedure 35
Figure 56. KY-57 input power circuit R-442 (test points).
Figure 57. Monitoring circuit (plain text).
Cipher text.
Figure 58. Monitoring circuit (cipher).
Muted/unmuted monitoring circuits.
Unmuted monitoring circuits.
A-RT keying circuit.
Figure 62. A-RT keying circuit.
Crew member's/driver's A-RT keying circuits.
Figure 64. AM-1780 TRANS switch.
Modulation Circuit
Signal within J-3513/U.
Signal to KY-57
Signal from KY-57 to RT
Signal to antenna.
Figure 70. Modulation circuit, KY-57 turn ON and cipher switch set to C.
Intercom signal
Signal through J-3513/U
Signal to antenna
Squelch disable circuit
A-RT audio output circuit
Figure 75. A-RT audio output (possible bad items)
General test procedures. - ss0728a0095
Test procedure 43
Test procedure 45
Test procedure 46
RT keying
Figure 76. RT keying, continuous keying (possible bad items)
Figure 77. RT keying, continuous keying (test points 1 and 2).
Figure 77. RT keying, continuous keying (test points 1 and 2) (cont)
Figure 78. RT keying, continuous keying (lower loop).
Figure 79. RT keying continuous keying (lower loop).
Figure 80. RT keying, continuous keying (lower loop).
Figure 81. RT keying, continuous keying (upper loop).
Figure 82. A-RT keying circuit, no keying (possible bad items).
Figure 83. A-RT keying circuit, no RT keying.
Figure 84. RT keying circuit, no RT keying.
Figure 85. RT keying circuit, no keying.
Figure 86. A-RT keying, no keying.
A-RT Modulation, Plain Text, KY-57 Turned Off
Figure 88. RT Modulation circuit, no voice sidetone (TP1).
Figure 89. RT Modulation circuit, no voice sidetone (TP2).
Figure 90. RT Modulation circuit, no voice sidetone (TP3).
Figure 91. RT Modulation circuit, no voice sidetone (TP4).
Figure 92. R-442 receive signal path.
Figure 92. R-442 receive signal path. (Cont)
Figure 93. R-442 receive signal path (speaker out).
Figure 94. R-442 receiver signal path (phone out).
Figure 94. R-442 receiver signal path (phone out). (cont)
Figure 95. R-442 receive signal path (monitor out).
Figure 95. R-442 receive signal path (monitor out). (Cont)
Signal monitoring.
Figure 96. Monitor circuit
R-442 Cipher Text Receive Signal Path, Monitoring Circuit (KY-57 ON, Mode Switch Set to C)
Figure 97. R-442 cipher text receive signal path, monitoring circuit (KY-57 turned ON, MODE switch set to C).
Figure 97. R-442 cipher text receive signal path, monitoring circuit (KY-57 turned ON, MODE switch set to C). (cont) - ss0728a0130
Figure 97. R-442 cipher text receive signal path, monitoring circuit (KY-57 turned ON, MODE switch set to C). (cont) - ss0728a0131
Figure 98. R-442 alarm clear and Fill keying circuit.
R-442 Audio Output Circuit
R-442 KY-57 Keying Alarm Clear Circuit
R-442 cipher signal path circuit
A-RT Continuously Keys (EPC Step 29b)
No Loud Rushing Noise Heard at the Commander Box
Test procedure 73.
No A-RT Keying (EPC Step 31)
No Sidestone (EPC Step 31)
No Loud Rushing Noise Heard at the Commander's C-2298
Test procedure 77.
No Loud Rushing Noise Heard at the Commander's C-2298 (EPC Step 36)
Figure 102. Squelch disable circuit (possible bad items).
General test procedures. - ss0728a0149
Figure 103. Jumper pin G to pin N.
Figure 104. Receive signal path, circuit (Possible bad items).
General test procedures. - ss0728a0152
Test procedure 83.
Summary - ss0728a0154
Objective - ss0728a0010
The circuits have been color coded
Operation Check
Figure 1. DC source voltage from vehicle communication power Bendix jack through MT-1029.
Figure 2. Mount MT-1029 configurations.
Figure 3. DC voltage path from pin B of J22 to AM-1780.
Figure 4. Intercom input power circuit.
Figure 5. Intercom keying circuit operating voltage (+24 volts DC).
Figure 6.Commander's intercom keying circuit (intercom keyed).
Figure 7. Intercom keying circuit (crew member and driver).
Figure 8. Talk circuit through C-2298 from J802 or J803.
Figure 9. Commander's voice signal path with MONITOR switch set to ALL, A, INT ONLY, or B.
Figure 10. Commander's voice signal, MONITOR switch set to C.
Figure 11. Crew voice signal MONITOR switch set to ALL, A, INT ONLY, or B.
Intercom listen circuit.
Figure 14. Listen signal to MONITOR switch.
Figure 16. Listen circuit (AC signal) from MONITOR switch through volume control to pins B and E of J802 or J803.
Figure 17. Intercom listen circuit.
Figure 18. Intercom input power problem listed on DA Form 2404.
Possible bad equipment. - ss0728a0029
Test procedure 1.
Test procedure 2.
Test procedure 3.
Test procedure 4.
Test procedure 5
Test procedure 6
Test procedure 7
Figure 27. Symptom observed when performing EPC step 1d.
Possible bad equipment. - ss0728a0038
General test procedures. - ss0728a0039
Test procedure 8
Test procedure 9
Test procedure 11.
Test procedure 13
Figure 33. No intercom keying, EPC step 2.
Figure 34. CDR intercom keying circuit.
Test procedure 14
Test procedure 15
Figure 37. Continuous intercom keying, EPC step 2.
Figure 38. Commander's intercom keying circuit, continuous keying.
No sidetone.
Figure 40. Talk/listen circuit.
Test procedure 18
Remote power circuit.
Return power circuit.
Figure 43. Return power to the J-3513 and KY-57.
Figure 44. Return power to R-442.
Figure 45. Return power to J-3514 and KY-57.
Input power.
Figure 47. A-RT dial lamp and AM-1780 power lamp do not light (possible bad items).
General test procedures. - ss0728a0060
Test procedure 22
Figure 49. Return power circuit (possible bad items).
General test procedures. - ss0728a0063
Figure 50. Return power circuit test points.
TSEC/KY-57 Input Power Circuit
Test procedure 28
Figure 52. KY-57 input power circuit: test points.
R-442 remote power control
General test procedures. - ss0728a0069
Figure 54. R-442 remote power control circuit (test points).
TSEC/KY-57 no input power
Test procedure 35
Figure 56. KY-57 input power circuit R-442 (test points).
Figure 57. Monitoring circuit (plain text).
Cipher text.
Figure 58. Monitoring circuit (cipher).
Muted/unmuted monitoring circuits.
Unmuted monitoring circuits.
A-RT keying circuit.
Figure 62. A-RT keying circuit.
Crew member's/driver's A-RT keying circuits.
Figure 64. AM-1780 TRANS switch.
Modulation Circuit
Signal within J-3513/U.
Signal to KY-57
Signal from KY-57 to RT
Signal to antenna.
Figure 70. Modulation circuit, KY-57 turn ON and cipher switch set to C.
Intercom signal
Signal through J-3513/U
Signal to antenna
Squelch disable circuit
A-RT audio output circuit
Figure 75. A-RT audio output (possible bad items)
General test procedures. - ss0728a0095
Test procedure 43
Test procedure 45
Test procedure 46
RT keying
Figure 76. RT keying, continuous keying (possible bad items)
Figure 77. RT keying, continuous keying (test points 1 and 2).
Figure 77. RT keying, continuous keying (test points 1 and 2) (cont)
Figure 78. RT keying, continuous keying (lower loop).
Figure 79. RT keying continuous keying (lower loop).
Figure 80. RT keying, continuous keying (lower loop).
Figure 81. RT keying, continuous keying (upper loop).
Figure 82. A-RT keying circuit, no keying (possible bad items).
Figure 83. A-RT keying circuit, no RT keying.
Figure 84. RT keying circuit, no RT keying.
Figure 85. RT keying circuit, no keying.
Figure 86. A-RT keying, no keying.
A-RT Modulation, Plain Text, KY-57 Turned Off
Figure 88. RT Modulation circuit, no voice sidetone (TP1).
Figure 89. RT Modulation circuit, no voice sidetone (TP2).
Figure 90. RT Modulation circuit, no voice sidetone (TP3).
Figure 91. RT Modulation circuit, no voice sidetone (TP4).
Figure 92. R-442 receive signal path.
Figure 92. R-442 receive signal path. (Cont)
Figure 93. R-442 receive signal path (speaker out).
Figure 94. R-442 receiver signal path (phone out).
Figure 94. R-442 receiver signal path (phone out). (cont)
Figure 95. R-442 receive signal path (monitor out).
Figure 95. R-442 receive signal path (monitor out). (Cont)
Signal monitoring.
Figure 96. Monitor circuit
R-442 Cipher Text Receive Signal Path, Monitoring Circuit (KY-57 ON, Mode Switch Set to C)
Figure 97. R-442 cipher text receive signal path, monitoring circuit (KY-57 turned ON, MODE switch set to C).
Figure 97. R-442 cipher text receive signal path, monitoring circuit (KY-57 turned ON, MODE switch set to C). (cont) - ss0728a0130
Figure 97. R-442 cipher text receive signal path, monitoring circuit (KY-57 turned ON, MODE switch set to C). (cont) - ss0728a0131
Figure 98. R-442 alarm clear and Fill keying circuit.
R-442 Audio Output Circuit
R-442 KY-57 Keying Alarm Clear Circuit
R-442 cipher signal path circuit
A-RT Continuously Keys (EPC Step 29b)
No Loud Rushing Noise Heard at the Commander Box
Test procedure 73.
No A-RT Keying (EPC Step 31)
No Sidestone (EPC Step 31)
No Loud Rushing Noise Heard at the Commander's C-2298
Test procedure 77.
No Loud Rushing Noise Heard at the Commander's C-2298 (EPC Step 36)
Figure 102. Squelch disable circuit (possible bad items).
General test procedures. - ss0728a0149
Figure 103. Jumper pin G to pin N.
Figure 104. Receive signal path, circuit (Possible bad items).
General test procedures. - ss0728a0152
Test procedure 83.
Summary - ss0728a0154
