Busy Station Signaling. How do I alert someone on the phone that they have a call?
If you make an intercom call and hear a busy tone
If you have voice mail and your phone is set to forward to voice mail when busy, this feature is not available (because no one will ever get a busy signal)
Press 1 or press the soft key below the display BSS (if your phone has one).
The CALL WAITING feature must have been pre-set on the receiving phone.
The busy station that you called either hears 3 beeps or you can whisper in their ear depending on the model phone they have and the call-waiting setting they are using. Either way they are alerted and know you are waiting for them.