Remote Electronics Unit

The remote electronics unit (REU) has an audio accessory unit (AAU) card that gets microphone inputs from attendant, service, and flight crew interfaces. The AAU card mixes them together, amplifies, and sends the audio signal to these places:

· Forward and aft attendant panel

· Interphone jack on the aft face of P8

· External service interphone jacks

· Captain, first officer, and observer station card.

General

The remote electronics unit (REU) processes service interphone audio signals. The audio accessory unit (AAU) circuit card in the REU contains service interphone circuits.

The service interphone circuits have an audio mixer. The audio mixer combines the microphone audio from the flight crew station cards, the attendant stations, and the service interphone jacks. The service interphone circuits increase the level of the audio signal. The audio goes to the flight crew station cards, the attendant stations, and the service interphone jacks.

Operation

The AAU card mixes these service interphone inputs:

· Flight compartment microphones

· Flight compartment handset microphone

· Attendant handset microphones

· Service interphone microphones when the service interphone switch is on.

Audio from the mixer goes to three audio amplifiers. The amplifier outputs go to:

· Flight compartment speakers and headsets

· Service interphone headsets

· Attendant handsets.

The gain controls are on the REU front panel. They change the amplifier gain. You do these adjustments in the shop. Use the calibration procedures in the aintenance manual.

Дата добавления: 2015-11-14