Sony IT-M602 Operating Instructions Manual page 11

Choose the dialing mode
For the telephone to work properly, select an appropriate dialing mode
(tone or pulse).
Depending on your dialing system, set the DIAL MODE switch as
follows:
If your dialing system is
Tone
Pulse
If you aren't sure of your dialing system
Make a trial call with the DIAL MODE switch set to T.
If the call connects, leave the switch as is; otherwise, set to P.
DIAL MODE switch
Set the switch to
T
P
EN
11
Getting Started