Using arduino to buffer or time-shift car fm radio

Forum 2005-2010 (read only) Hardware Interfacing
1

Hello all, I am thinking of taking on my first real arduino project. I am definitely more of a software geek but am trying to learn more about the hardware side of things. So I apologize if my knowledge is still lacking on some basic hardware concepts. Right then, on to the good stuff :slight_smile:

The project I had in mind is to hook the arduino up to my car radio (either my existing radio or another one I may buy if it is easier) to implement a buffer that would capture audio from the radio and allow me to rewind or pause similar to a tivo or other dvr device.

My thought was that I could insert the arduino (along with a hard drive) somewhere in between the radio components that are responsible for pulling the signal in from the airwaves and whatever sends it to the speakers. I've been looking around for similar projects but haven't found anything that quite matches this, and I'm not really sure yet how much work is involved for each of these steps. Am I getting in over my head here, or is there a simpler way?

The steps I was envisioning are:

  • FM data is pulled off the airwaves by the radio and instead of being sent to the speakers it is sent to the arduino
  • Arduino saves it to a flash drive
  • Arduino replays data it has saved, either live or time-shifted and sends it to the speakers
2

Thanks for all the information, it sounds like this might be more suited for a car pc then. Good to know before I got too deep into this.

Just out of curiousity, any idea how the car radio handles this "on the fly"? It would seem like there should be a point somewhere along the radio circuit that the data has been converted to digital signals such that it could be saved as raw data and possibly re-broadcasted later?

3

There are MP3 encoder/decoder chipsets out there that could be controlled by the Arduino; something to be considered...

4

Something like this shield, perhaps:

In some manner, it can encode and decode Ogg Vorbis - so in theory, you could encode to Ogg, dump it to an SD card, then later play it back using the same shield...

:slight_smile: