Dual Tone Multi Frequency
(DTMF, or "touch-tone") A method used by the telephone system to communicate the keys pressed when dialling. Pressing a key on the phone's keypad generates two simultaneous tones, one for the row and one for the column. These are decoded by the exchange to determine which key was pressed.
Last updated: 1995-03-28
dual ported ♦ dual-stack ♦ Dual Tone Multi Frequency ♦ duck typing ♦ DUEL
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