Sunday, January 31, 2016

Arduino DTMF Decoder and Relay Controller

Another Arduino project I've been working on is a DTMF decoder used to control a relay board. Using a ham radio receiver, I can switch lights, radios, computers...anything...on or off from miles away. Here's the video:


Here's the wiring diagram. And here's the Arduino code.

I'm using a Sainsmart 4 relay board, although pretty much any relay board would work. You'll also need a MT8870 DTMF decoder - these run about $2 on ebay. And of course, you'll need an Arduino Uno. Again, check out ebay for these as well. The total cost here should be less than $12 and you've got a fully functioning radio controlled DTMF relay controller!



4 comments:

Peter Martin said...

Excellent video. I etched a DTMF circuit board and soldered it up -- intend to experiment with relay switches. Exactly what I was looking for. Thanks.
Pete Zenner
KE0BRS
Sioux Falls, SD

Michael Brown said...

The files can be found on github as well!

https://github.com/MichaelDBrown/ardunio_dtmf_relay

Mike said...

Looks like an awesome project. Although I'm stuck with some errors. I got the timer error fixed but now run into this one. I'm stumped over it. Any suggestions?

sketch_nov10b.ino:61:10: error: ‘class EEPROMClass’ has no member named ‘get’
sketch_nov10b.ino:82:14: error: ‘class EEPROMClass’ has no member named ‘put’
sketch_nov10b.ino:83:14: error: ‘class EEPROMClass’ has no member named ‘put’

Michael Brown said...

Hey Mike, google that error and you’ll find that you likely have an old version of the eeprom class installed in the arduino development environment.