AT&T MERLIN LEGEND System Reference Manual page 123

Features
Conference
Extension Programming
Description
2-74 Conference
Behind Switch Mode Only:
Programming Code:
Conference: *772
Drop: *773
MLX Display Label:
Conference: Conference [Conf]
Drop: Drop
Through Conference, a user can establish a conference call by using a
combination of inside and/or outside lines. Conference calls originated from
multiline telephones can have a total of five participants-the originator plus two
outside lines and two extensions. Conference calls originated from single-fine
telephones can have a total of three participants-the originator plus two others
in any combination of inside or outside lines.
A user can consult privately with each participant before adding the person to
the conference. Anyone who shares an outside line or System Access button
with the user can join the conference on that button and is counted as a
participant.
A multiline telephone user can selectively drop conference participants while the
conference is in progress by using the Drop button. However, a queued call
console (QCC) system operator cannot selectively drop participants from a
conference. When the QCC system operator presses the Drop button, only the
most recently added participant is dropped. Sligle-line telephone users can
drop the most recently added participant from the conference by pressing and
releasing the Recall button or switchhook.
The conference originator can leave the conference by pressing the Hold button
(the conference continues). If a conference originator (excluding a QCC system
operator) leaves a conference by either hanging up or selecting another line, the
entire conference is disconnected.
A QCC system operator can press the Release button after originating a
conference involving three participants (including the system operator), which
disconnects the system operator from the conference but leaves the other
participants connected. A QCC system operator cannot, however, release a
conference involving four or five participants. if the QCC system operator hangs
up or selects another Call button, the conference is put on hold.