Taidacent DTMF Decoder/Encoder Full Form Dial Tone Generator Dual Tone Multi-Frequency Audio Decoding Digital Display: Amazon.com: Industrial & Scientific
Nerd Club: Telephone dialler (DTMF tone generator using PIC 16F1825) for dementia sufferers
Nerd Club: Telephone dialler (DTMF tone generator using PIC 16F1825) for dementia sufferers
Touch-Tone Telephone Dialing » Cleve's Corner: Cleve Moler on Mathematics and Computing - MATLAB & Simulink
Dual Tone Multi Frequency (DTMF) - Signal Identification Wiki