General Audio: Pulse dialing vs Dual-tone multi-frequency (DTMF), also known as Touch Tone

Pulse dialing, also called Rotary dialing, is Pulsing in which a direct-current pulse train is produced by interrupting a steady signal according to a fixed or formatted code for each digit and at a standard pulse repetition rate. Dial pulsing originated with a rotary dial integrated into telephone instruments, for the purpose of signaling. Subsequent applications use electronic circuits to generate dial pulses. DTMF (Dual Tone Multi-Frequency) also known as Touch Tone,- A term used to describe the audio signaling frequencies where each key generates two audio tones. DTMF was developed at Bell Labs in order to allow dialing signals to dial long-distance numbers, potentially over non-wire links such as microwave links or satellites. Since the 1960's DTMF or Tone dialing has become the standard for most phone systems in the Western world. All Software Versions