AT&T MERLIN LEGEND Reference page 53

F e a t u r e s
4. Dial the feature code assigned by the local telephone company to activate
Automatic Callback.
Wait for the confirmation tone (a three-burst tone) to ensure that the
feature was activated correctly.
The telephone number from which the last call was received on the BRI
line is automatically dialed by the central office.
If the telephone number being called is available, you hear ringback.
If the telephone number being called is busy, the central office "camps"
or queues the recall attempt at the called number. When the number
becomes available, the central office calls you back on the BRI line used
to place the call. All telephones sharing the Personal Line button ring with
a priority ring (four-burst ring for MLX telephones and three-burst ring for
analog multiline telephones) to indicate the completed call.
Considerations and Constraints
Automatic Callback should be used for calls received on Personal Line buttons
only.
Mode Differences
In the Hybrid/PBX mode, Automatic Callback should not be activated for calls
received on any type of System Access button or on a Pool button, because
there is no way to identify the last BRI line used to receive a particular call.
Telephone Differences
Automatic Callback should not be used on single-line telephones since a single-
Iine telephone user cannot identify the BRI line on which an incoming call was
received.
Automatic Callback
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