AT&T 7402 - Manual (Page 17)

Conference
To add another party
to a call 1 Press Conference
Ring
[[dial tone]
Present call temporarily put on hold and you are
given a new call appearance
2 Dial number of third party and wait for answer
Note: You can privately discuss the call with the
third party at this time; if no answer or busy, press
fluttering
xxxxx to return to the original party.
3 Press Conference
Ring
again
All parties now connected
To add a call you have
put on hold to another
call you are connected to 1 Press Conference
Ring
[dial tone]
2 Press xxxxx of first call
3 Press Conference
Ring
again
All parties now connected
To drop third party 1 Press Drop
Test
You remain connected to original party
Note: If both call appearances are in use, you will not
be able to use this feature.
Drop
To disconnect from a
normal call, or to drop
the last party added to a
conference call 1 Press Drop
Test
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