[Colin] wanted a way to reliably control an Arduino via ham radio. One of the easiest methods of automated radio control makes use of Dual-Tone Multi-Frequency signalling. To those who aren’t into ...

int STQ = 3; // DTMF Module STQ Pin connects to Arduino Digital Pin 3 int Q4 = 4; // DTMF Module Q4 Pin connects to Arduino Digital Pin 4 int Q3 = 5; // DTMF Module Q3 Pin connects to Arduino Digital ...

While many of us have banished land line telephones from our houses, there are still quite a few people who utilize POTS lines today. These analog phone systems use Dual Tone Multi Frequency (DTMF) ...