AT&T SYSTEM 25 User Manual page 29

Screen 2 is unchanged:
After the called party answers, pressing <SOURCE> returns
the calling party information to the screen:
If you now press <DEST>, called party information appears
on the screen again:
If you press <JOIN>, Screen 1 shows a conference
connection:
Pressing <RELEASE> causes Screen 1 to go blank.
1 5 0 1 D I D
1 5 0 1 D I D
&1728 Taylor,B
CONFERENCE 3
Extending Calls (Contd)
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