P139-HD Audio System User Manual
GA063-3 Rev G 08/25/2015
Page 11 of 35
5. Alert Tones
5.1. Description
The P139-HD Audio system supports up to 8 built-in Alert Tones that may be triggered by external events
to act as a notification or warning to the crew. External triggers must be a pull-low to ground.
When an alert is triggered, the alert will continue to sound until one of the following events occurs:
1.
The condition triggering the alert is cleared by the alerting device.
2.
The “Alert cancel” button is depressed (if installed).
3.
A higher-priority alert is triggered. If the high priority alert is cleared, the low-priority alert will again
sound.
4.
The alert may be muted while transmitting on a radio, if the alert has been configured to Mute on
Transmit.
5.2. Call Indicator
The Audio System may be configured for a cabin call indicator using one of the Alert Tone generators.
The operation of the Call Indicator is as follows:
1.
If a CALL button is pressed, the call tone will be heard by the crew, and the call indicator will flash
on the control panel.
2.
The call tone and indicator may be cancelled by the deselecting the CALL button. In some
installations, deselecting the ICS Isolate function (ISO) from the flight deck control panels also
cancels the CALL function.
