Ericsson DT190 User Manual page 92

Reference
92
Phone signals
The Cordless phone generates audible ringing signals, alarm
signals, warning tones and key clicks.
Sound Meaning
Ring signal Incoming call
Alarm signal 1 short beep every 30 seconds: Battery almost
empty
Key click You hear this each time you press a key (when
selected).
Warning tone You have pressed a key which has no function.
An entry or setting has not been completed
successfully.
Confirmation tone An entry or setting has been completed
successfully.
BusinessPhone – Cordless phone DT190