I need to know the difference between the three Signalling Types for Multilines delivered by NTTP into a Telephone System or PBX, they are :-
Pulse Tone
Touch Tone
Dual Tone
I am lead to believe that Pulse Tone is as per the old Rotary Pulse Dials and Touch Tone is by DTMF (Dual Tone Multi Frequency) but if these are correct, what then is Dual Tone?
I have searched in Openeach and cannot find out this information.