Topcom Butler 4812 USB VoIP
•Press the Up or Down key 
repeatedly until ‘VOLUME’ appears on the display.
•Press the Programming key 
.
•The current volume level used appears on the display.
•Enter a number between 0 and 9 to select the desired ringer volume. Use the number keypad to do this.
•Press the Programming key 
to confirm your selection.
4.19 Locking the key pad
If you lock the alphanumeric keypad, it is impossible to dial a telephone number.
Only the Programming key 
can still be used. ‘KEY LOCKED’ will be displayed on the display.
•Press the Programming key 
.
•Press the Up or Down key 
repeatedly until ‘KEY SETUP’ appears on the display.
•Press the Programming key 
.
•KEY LOCK‘ appears on the display.
•Press the Programming key 
.
•The current status of the keypad appears on the display:
–‘LOCK’: the keypad is locked
–‘UNLOCK’: the keypad is not locked
•Press the Up or Down key 
to make your selection.
•Press the Programming key 
to confirm your selection.
You can also Press and hold the
4.20 Turning key click ON/OFF
You can set the telephone to make a sound whenever you press a key.
•Press the Programming key 
.
•Press the Up or Down key 
repeatedly until ‘KEY SETUP’ appears on the display.
•Press the Programming key 
.
•Press the Up or Down key 
repeatedly until ‘KEY CLICK’ appears on the display.
•Press the Programming key 
.
•The current status appears on the display:
–‘CLICK ON’: turn on key click
–‘CLICK OFF’: turn off key click
•Press the Up or Down key 
to make your selection.
•Press the Programming key 
to confirm your selection.
4.21 The R key (flash)
Press the Flash key ‘R’ to use certain services such as “call waiting” (if your telephone company offers this feature); or to transfer calls if you use a telephone exchange (PABX). The Flash key ‘R’ is a brief interruption of the line. You can set the flash time to 100ms or
18 | Topcom Butler 4812 USB VoIP |