Panasonic KX-NCP500 User Manual page 78

SLT
During a conversation
Press Recall/
hookswitch.
On-hook.
Default
(Tone 1)
Special Tones
(Tone 2)
5 0
C.Tone
Enter 50.
Off-hook.
Enter
5 s
Talk to the
original party.
5 0
C.Tone
50.
15 s
OR
Talk to the
new party.