Bose A20 Aviation Owner's guide - Page 37

English Tab 2, 10 Tab 3, 11 Tab 4, 12 Tab 5, 13 Tab 6, 14 Tab 7, 15 Tab 8, 16 INSTALLATION Helicopter (U174) connection diagram Existing wiring to helicopter intercom/ audio panel WHT/BLU 6 WHT 5 BLU 4 WHT 3 BLK 10-32 RED V DC 1/2A 2 1 MIC LO MIC HI COMM R COMM L GND V+IN Existing single 4- prong jack Barrel (audio gnd) Note: Barrel ground (gnd) refers to aircraft grounds. Details on making the connections The pinouts for the optional installed connector are detailed in the table below: Pin number Color Purpose 1 Red V+IN: Headset power (10-32 VDC). Use a /1 4 amp fuse or a /1 2 amp circuit breaker. 2 Black GND: System ground. Connect to the existing audio ground. 3 White COMM L: Phone communication: Left. 4 Blue COMM R: Phone communication: Right. Note: For stereo operation, connect the left and right channels to their respective positions. For monaural operation, connect pins 3 and 4 together, and to the tip of the existing phone jack. 5 White MIC HI: Microphone/Hi-audio. Connect to the portion of the existing microphone jack that corresponds to the ring position of a headset microphone plug. Do not connect to the tip (PTT) segment. 6 White/ MIC LO: Microphone/Lo-ground. Connect to the portion of Blue the microphone jack that corresponds to the barrel position of a headset microphone plug. Note: If the microphone works on radio transmit but not through the intercom, check pin 6. It may be incorrectly wired to the PTT segment of the microphone jack. Comm Shield Black Shield from Comm L and Comm R wire pair. Mic Shield Black Shield from Mic Hi and Mic Lo wire pair. Note: The wires connecting pins 3 and 4 and pins 5 and 6 are shielded, twisted pairs with a black wire shield termination exiting each pair. If the existing wiring is not shielded, connect the shields to the existing audio wiring shields, or connect the shield from Comm L and Comm R wire pair to audio ground. 33