INTERCOMMUNICATION SET, AN/VIC 1(V). Continued

TM 11-5820-890-20-2 1-39 1.13. INTERCOMMUNICATION SET, AN/VIC 1(V). Continued RADIO TO BE MONITOR SWITCH RT A RT B MONITORED SETTING A C SINGLE RADIO MOUNT ALL (a) •ALL" Position. The •ALL" position provides for monitoring of the intercom, all RTs, and control of RT A. In the •ALL" position, the fixed audio output of all RTs and intercom are applied to pin •L" of connector J804/J801. From pin "L" of J804/J801, the audio is applied to the MONITOR switch and then to the VOLUME control. From the VOLUME control, the audio goes to pins B and E of J802 and J803. RT A is keyed by grounding pin C of J802 through the handset PTT switch. This ground is applied through the MONITOR switch to pin D on J804/J801. The mic audio signal from the handset is applied to pin D of J802. From pin D the audio is sent to the amplifier A80. The amplified audio signal is then applied to pin K of J804/J801. When used with a single radio mount, the •ALL" position will be the only setting that the RT can be heard from. The variable audio lines are not connected in the power supply adapter. (b) •A" Position. In position •A", RT A variable audio signals are applied to pin M of J804/J801. From pin M, the audio is applied to the MONITOR switch, through the switch to the VOLUME control and then to pin B and pin E of J802 and J803. The keying and mic circuits are the same as for the •ALL" position. (c) •INT ONLY" Position. When the MONITOR switch is in •INT ONLY", the C 2298/VRC can key only the intercom. However, when the intercom is keyed, both intercom and radio audio can be heard. The audio is applied to J804/J801, pin E, and then to the MONITOR switch. From the MONITOR switch, the audio is applied through the VOLUME control to pins B and E of J802 and J803. To key the intercom, the ground from the handset PTT at connector J802 is applied to the MONITOR switch and J804/J801, pin H. Other keying contacts of the MONITOR switch are open, therefore the RT is not keyed. The mic circuits are the same as for the •ALL" position. (d) •B" Position. Not used with SINCGARS RADIOS. (e) •C" Position. In position •C", RT B variable audio is applied to J804/J801, pin J, and then to the MONITOR switch, through the switch, to the VOLUME control, and then to pins B and E of J802 and J803. RT B is keyed when a ground is applied to pin C of J802. The ground is applied through the MONITOR switch to pin F of J801/J804. The mic audio signal from the handset is applied to pin D of J802. From pin D the audio is taken to the amplifier A80. The amplified audio signal is then applied to pin V of J804/J801. In some tracked vehicles, this position may not be operational due to limited circuits in the CX 7060/VRC cable and slip ring assembly. When the intercom is activated by another crew member, the intercom audio will not be heard if the MONITOR switch is in the •C" position, or if the crew box is connected to the commander's port (J504) on the AM 1780/VRC.