Panasonic KX-TD500 User Manual page 171

Answering an intercom recall
PT and SLT
If you hear the telephone ringing;
Lift the handset or press SP-PHONE/MONITOR.
<PT Display Example>
xxxx: Free
You hear a ringback tone and the other extension begins to
ring automatically.
Answering a CO line recall
PT and SLT
If you hear the telephone ringing;
Lift the handset or press
SP-PHONE/MONITOR.
<PT Display Example>
10101: Free
User Manual
extension number
Dial tone
Trunk port physical number
Station Features and Operation (PT/SLT)
phone no.
Dial the phone number.
171