Panasonic KX-NS1000 Operating Manual page 356

5.3.1 Feature Number Table
(While busy, DND or call tone is heard/after dialling)
Joining an Existing Call (Executive Busy Override)
Leaving a Message Waiting Indication/Calling Back the Caller Who
Left an Indication (Message Waiting)
Monitoring Another Extension (Call Monitor)
Reserving a Busy Line (Automatic Callback Busy)/
Callback on an ISDN Line (Completion of Calls to Busy Subscriber
[CCBS])
1.2.6 Alternating the Calling Method (Alternate Calling—Ring/Voice)
1.4.5 Multiple Party Conversation
Adding Other Parties during a Conversation (Conference)
1.11.1 If a Doorphone/Door Opener is Connected
From any extension while talking to the doorphone
356 Operating Manual
Feature
Feature
(While dialling or talking)
Setting
Default
3
4
5
6
Fixed Number
3
5