hello guys..
our new and one of the best project phone calling arduino robot
using dtmf decoder module based on arduino…
What is DTMF?DTMF is a Dual Tone Multiple Frequency decoder module which has a MT8870 DTMF decoder IC which decodes DTMF tone signal to digital signal that are acceptable for arduino digitally. Here an aux wire is needed for connecting DTMF module to phone.”

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