Hey guys i have a mp3 player and was woundering if it would be wise to use something like:

MRF24J40MA

I want to send the audio from player to this and then send receive it on another. I know i need a pretty fast pic ie: 16bit - 32bit to handle it correct?

So my main question is can i use the above transceiver module and a fast pic to do it all?

heh thanks... what would u recommend?

cool ! i think the breadboard would not be a good idea but im going to try it too heh... i dont have no modules as of yet but i might order today. or tomorrow ...

Im not dealing with MP3 data. Im dealing with audio from a mp3 player. So ADC is needed but fast... then on the other side DAC...

Since i just want to turn the audio into digital data then send the data wireless to the other one and turn the digital data back to analog audio.

Sort of like a FM transmitter/receiver but FM sux in my opinion. heh

so nice audio is about 128kbs (i think) so 250 should be a nice overkill to have since i have to do a ADC then send it out then repeat. I should be able to do it fast enough. There may be a small delay in music changing and stuff but heh it will be worth it

Originally Posted by AtomSoft

so nice audio is about 128kbs (i think) so 250 should be a nice overkill to have since i have to do a ADC then send it out then repeat. I should be able to do it fast enough. There may be a small delay in music changing and stuff but heh it will be worth it

128kps is MPEG compressed, not plain audio - half that for stereo, you're down to 64kps, which is only 6400 bytes per second. Assuming you're only using 8 bit data, that's about a 3KHz bandwidth - a very poor AM radio.

Do the maths!.

Originally Posted by Mr RB

You can buy nice pre-made stereo FM transmitters made just for this purpose.

I know you said you didn't want to use an FM transmitter but it's looking better and better...

It always did!

It's a nice idea to build a digital one, but people don't think about it first.

Nigel and RB I just hate the noise that it has. Is it possible the ones i dealt with were too cheap and crap.

So if i build one you think it will be better? Any links to some?

Also nigel what kinda speed would i need to send stereo quality audio wireless?

Originally Posted by AtomSoft

Nigel and RB I just hate the noise that it has. Is it possible the ones i dealt with were too cheap and crap.

The quality is normally excellent, were you trying to use them over too great a range?.

So if i build one you think it will be better? Any links to some?

Also nigel what kinda speed would i need to send stereo quality audio wireless?

CD quality is sampled at 44.1KHz and 16 bits per channel, so that's 1.76mbs, assuming 10 bit data bytes as per RS232.

And note that 1.764mb/sec is beyond the capabilities of the PIC18F to generate. The DSP chips, maybe not.

Now COMPRESSED data MP3/Ogg/whatever is far more practical. However, even the DSP chips have only limited ability to do the necessary math. There are many decompressor chips for MP3, but compressors are quite rare.

So, you can start with an MP3 file on flash card and beam that to a receiver with an MP3 decoder on board. That's straightforward. It's within the bandwidth of higher performance hardware like Bluetooth. But... starting with an analog input, you've got no straightforward way to compress the data with any useful quality.

I have noted abuse of the term "codec" chip for these compression formats. "codec" means "coder" AND "decoder". Most claiming to be codecs are in actuality decoders. Some have an ADC to encode incoming audio into uncompressed digital data, which may be a useful task to some, but it is NOT MP3/Ogg/etc encoding and it's misleading to term this an "Ogg codec" when it does not encode into Ogg.

heh i might just use some ARM mcu's. Im thinking of some cheap $5 LPC2103's to do that stuff for me