Helicopter (U174) Connection Diagram; Details On Making The Connections - Bose A20 Guia Del Usuario

Technical Information

Helicopter (U174) connection diagram

Existing wiring to
helicopter intercom/
audio panel
Barrel ground (gnd) refers to aircraft grounds.
Note:

Details on making the connections

The pinouts for the optional installed connector are detailed in the table below:
Pin number
1
2
3
4
Note: Monaural use cases should not tie left and right audio sources together due to auto
sensing systems found in many intercom systems.
5
6
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
Mic Shield
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.
38 - English
WHT/BLU
10-32
V DC
Tip
(MIC HI)
Color Purpose
Red V+IN: Headset power (10-32 VDC). Use a 1/4 amp fuse or
a 1/2 amp circuit breaker.
Black GND: System ground. Connect to the existing audio
ground.
White COMM L: Phone communication: Left.
Blue COMM R: Phone communication: Right.
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.
White/Blue MIC LO: Microphone/Lo-ground. Connect to the portion
of the microphone jack that corresponds to the barrel
position of a headset microphone plug.
Black Shield from Comm L and Comm R wire pair.
Black
Shield from Mic Hi and Mic Lo wire pair.
6 MIC LO
WHT
5 MIC HI
BLU
4 COMM R
WHT
3 COMM L
BLK
2 GND
RED
1 V+IN
1/2A
Existing single 4-
prong jack
Barrel
(audio gnd)