23-51-00
ALL ú ú 08 Page 9 ú Jul 12/00
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A 737-300/400/500MAINTENANCE MANUAL
8. Oxygen Mask Microphones (Fig. 2)
_______________________
A. The oxygen mask has a microphone built into the mask. Each mask is equipped with an oxygen connection and a microphone plug. A control wheel or audio selector panel PTT switch must be pushed before transmission can take place. The mask microphone is plugged into jacks at each flight crewmember's station.
9. Control Wheel Push-To-Talk Switch
_________________________________
A. The Push-To-Talk (PTT) switch on the control wheel provides PTT input form the boom or oxygen mask microphones.
B. The PTT switch is a three position switch on the outboard horn of the captain's and the first officer's control wheel. In the MIC position, microphone audio is directed to the selected communication system. In the INT position, microphone audio is connected directly to the flight interphone system without making microphone selection on the audio selector panel. The switch is spring loaded to the center "OFF" position.
10. Operation (Fig. 3)
_________
A. General
(1)
AIRPLANES WITH DIGITAL AUDIO CONTROL SYSTEM; All audio inputs from the flight interphone system, service interphone system, radio communication systems, and radio navigation systems are connected directly to the remote electronics unit where they are processed into multiplex channels. The flight crew can then use their audio selector panels to select the multiplex channel they wish to hear on their headphones or headsets. They can also connect the PA channel to the passenger address amplifier.
(2)
AIRPLANES WITHOUT DIGITAL AUDIO CONTROL SYSTEM; All audio inputs from the flight interphone system, service interphone system, radio communication systems, and radio navigation systems are connected directly to the audio accessory unit where they are processed. The flight crew can then use their audio selector panels to select the channel they wish to hear on their headphones or headsets. They can also connect the PA channel to the passenger address amplifier.
(3)
AIRPLANES WITH DIGITAL AUDIO CONTROL SYSTEM; The flight interphone system hand held, boom, and oxygen mask microphones provide the microphone audio inputs from the flight crew to the remote electronics unit. The MIC SELECTOR switches on each audio selector panel determine which one of the communication or interphone systems will receive the microphone input for transmission. All audio selector panels functions are connected in parallel to the REU. The same communications are monitored by all flight crewmembers.
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址:737-300 400 500 AMM 飞机维护手册 通讯 COMMUNICATIONS(81)