The 35-Type station dial. Source: The Beatrice Company Bell Labs conducted exhaustive research to determine the best methods for tone dialing. They settled on a DTMF system for the control tones ...

[Rogal] wrote a cell phone application called ToneTool that generates audio tone sequences. It can be used to output DTMF and SelCall sequences which are used by telephone systems and radio ...

What is Touch-Tone Signaling? Touch-tone is an example of dual-tone multifrequency (DTMF) signaling. As the name suggests, touch-tone involves simultaneously sending two tones from a set of multiple ...

Rotary dial phones employed a series of pulses ... Researchers at Bell Laboratories developed the dual-tone multi-frequency (DTMF) technology that provided the touch-tone service in the late ...

Known as the dual-tone multifrequency (DTMF) system, the signal is a combination of the row and column frequencies of the digit key. THIS DEFINITION IS FOR PERSONAL USE ONLY. All other ...