Arduino Producing DTMF Tones


Posted on Feb 5, 2014

I wanted to teach my Arduino to talk telephone, so I added a HT9000A DTMF chip to produce the familiar `touch tones` (upcoming projects will act upon `heard` DTMF tones, but with a different chip). The output is really low volume, so you may want to plug in amplified speakers or use an input on your stereo. You could build an amplifier


Arduino Producing DTMF Tones
Click here to download the full size of the above Circuit.

circuit with a LM386 as well. I used an Ham Radio program that listens for touch tones and displays the number it hears to verify operation.




Leave Comment

characters left:

New Circuits

.

 


Popular Circuits

FM Transmitter
5V Supply High-Side Switcher
Acoustic Field Generator Circuit
Nikon CLS Slave Flash Trigger
power supply variable with lm338
Astable Multivibrator Calculations
555 LED Flasher Circuit
BJT H-bridge Implementation
Float Switch Water Level Measurement
4-Bit Computer



Top