AASTRA DT4x2 for MX-ONE User Guide EN - Manual (Page 92)

Alarm
DT412/DT422/DT432 92
Personal Alarm
Activate
Press the red Alarm key twice within 2 seconds.
The display shows Personal Alarm and an alarm is sent to the
alarm central. After that, the phone returns to idle mode.
Note: You can always trigger the alarm, even when you are
speaking, editing your settings or while the phone is locked.
Cancel
C
Press to cancel the Personal Alarm (see display).
Test Alarm
Press and hold the red Alarm key until the information text is
displayed.
The default information text is
Test Alarm .
C
Press to cancel (see display).