User guide

Basic Functions
33
Muting Mobile Unit
If you do not want the caller to hear, e.g. what you are discussing with someone
else in the room, you can temporarily mute your mobile unit.
Muting
Press the softkey. The person you are speaking with on the telephone can no
longer hear you.
Cancel muting
When you wish to talk to the caller again, press the softkey once again. The
caller on the telephone can hear you again.
Changing Display Contrast
To adjust the display to current lighting/brightness conditions, you can change
the contrast. You can enter the emergency call number in the “Phone settings >
Telephone Option > Disp. contrast” menu (see page 83).
Time/Alarm
When idle the display shows the current communications system time. The time is
automatically updated after an external call. After commissioning or after
changing the battery it may take a moment until the current time is transmitted
from the OpenCom 100 / Aastra 800.
If you have set an alarm (see page 78) the symbol appears on the display.
Message Display
The B info key flashes when you have messages. When a short message or e-mail
is received, the symbol appears on the display; when a voicebox message is
received, the symbol.
To query these messages, press the
B info key briefly when idle. For information
on how to proceed, please consult the chapter “Info” Menu starting on page 91.
Emergency Call Key (SOS Number)
An emergency call is triggered by a long key press of the R emergency call key.
You can configure the emergency call number in the “Telephone Option> Emer-
gency call” menu (see page 82). Dialling is immediately executed – i.e. no other
key presses necessary.