Northern Airborne Technology AA82 - Manual (Page 23)

AA82 InterMUSIC™ Stereo Intercom System
SM09-1 Installation and Operation Manual
Section 3 Rev: 1.00 Issue 4 Page 3-2
ENG-FORM: 806-0112.DOT
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
3.3.1 Stereo & Intercom Special Features
The stereo music audio is muted during intercom operation and when radio receive audio is detected,
permitting greater intelligibility of incoming transmissions. The AA82 Muting adjustment ranges from
complete music muting to gentle background music on command, with a fast attack and slow level return
for optimum user comfort. Each microphone is individually gated for the best possible noise performance
during VOX operation. A front panel annunciator allows easy visual setting of the VOX threshold and also
indicates radio signal reception.
3.3.2 Logic Explanation
When ICS or RX functions are active, any music will be muted quickly as shown in Table 1. The music will
slowly return when transmission is completed. The degree of muting is set at the time of installation. The
relative volume of the music can be changed from the front panel by adjusting the music volume knob
marked with a musical note.
Active: Function being used
Muted: Functions that are overridden by the active condition
Idle:
Functions that are not active, but still available for use
Music ICS RX
Active Idle Idle
Muted Active Idle
Muted Idle Active
Muted Active Active
Table 1
Music Muting
3.3.3 Tie/Split Operation
The crew audio system that the AA82 is connected to may have a Tie/Split mode of operation. The crew's
Tie/Split switch connects or disconnects the ICS Tie Line from the passengers' intercom system. Intercom
between the passengers is maintained, but they are cut off from the crew ICS and radio audio. Many
different circuit combinations can be set up depending on what device is hooked to the Tie Line.
Section 3 ends