AT&T System 25 - Manual (Page 18)

Conference Calls (Continued)
5 Press the
LOOP
button next to the blinking light to add this
person to the conference.
The loop where the last conferee was called becomes idle again.
6 If you want to add another conferee, return to Step 2 and
continue.
Display
Each time a party is called for a conference, the normal
information is displayed.
Call to an inside extension:
311 Dunn,B 2
Call to an outside number:
95551634 2
As each new person is added to the original loop, the display
shows the number of conferees (including you) now connected
together, along with the current number of calls waiting in the
queue.
CONFERENCE 3 2
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