AT&T Definity ISDN 7507 - Manual (Page 49)

Tones and Their Meanings
Ringing tones are produced by an incoming call. Handset tones are those which you
hear through the handset (receiver).
Ringing Tones
● 1 ring — A call from another extension.
● 2 rings — A call from outside or from the attendant.
● 3 rings — A priority call from another extension, or from an Automatic Callback call
you placed.
● ring-ping (half ring, not repeated) — A call redirected from your voice terminal to
another because Send All Calls or Call Forwarding—Follow Me is active.
Handset Tones
●
busy tone — A low-pitched tone repeated 60 times a minute; indicates the number
dialed is in use.
● call waiting ringback tone — A ringback tone with a lower-pitched signal at the
end; indicates that the extension called is busy, but the called party has been given
a call waiting tone.