How would I make an AVR radio-recorder?

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I'd like a device that I could use to record the BBC World-Service off NPR (National Public Radio - a network of stations in the USA that is not exclusively commercials and pop music oriented) FM radio. The BBC is broadcast in the middle of the night here and I don't have the option to listen to it live between 12 and 3 AM.
I'd like to record about three hours each night (mono is fine), convert it to a reasonable quality (128kbps if mono; 192kbps if stereo) MP3 file, and store it as a series of 15 minute files on a flash drive. I'd just stick the flash drive in before going to bed, pop it out in the morning, and listen to (and skip to different sections or files) while traveling to work or at work using an MP3 player like WinAmp. It wouldn't hurt to have a stereo MP3 player built in.
I'd love to have something like this. But since nobody in the commercial electronics industry knows or cares what anyone actually wants to buy, this kind of device isn't available anywhere at any price. And since a device like this doesn't make Steve Jobs look any cooler or get any richer, even if it in itself 'insanely great', Apple is unlikely to make anything like it.

So it looks like I (or we) are just going to have to do it ourselves.

It needs an FM tuner, a real-time clock, an audio to MP3 convertor (and vice versa), a USB interface, and a file system to store the recorded audio onto the flash drive.

A variation of this device could be used by people who are about to sign a lease on an apartment but want to know if there are going to be any nasty surprises that the landlord isn't telling them about. They could insist that they be allowed to record 48 hours of background sound in the bedroom of the rental unit in order to know that the neighbors don't come home at 3AM and, without a thought, turn on the hip-hop at 100 dB. Or there isn't a newspaper distributor next door that comes alive at 3am with 100+ cars pulling in and out every night 365 days a year. The 48 hours of tapes could be run through a sound detection/analysis program (that probably doesn't exist) that would detect things that would drive you crazy when you are trying to get to sleep from the MP3 data.

Any thoughts?

do you know of a device that does these things already?

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why not just use your computer mic port to record?

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I'm not sure if this is the station you want, but most npr stations also stream live. Open-
http://stream1.opb.org/radio.mp3
in vlc, and capture. I assume you have a computer, and I assume you have internet access (at least you are 'here'). So just figure a way to capture the mp3 stream with your pc (not difficult- as I'm doing it right now with vlc).

Not that there is anything wrong with making a device as you want to do, but your pc could be recording tonight.

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Quote:

But since nobody in the commercial electronics industry knows or cares what anyone actually wants to buy, this kind of device isn't available anywhere at any price.

My Creative Zen Vision W has an FM radio and can record. But I think there were legal problems with this in the US and the firmware for the unit there has the radio recording disabled. So presumably this is why there is no such commercial product in the US?

BTW are you seriously suggesting you could do this on an AVR8 (subject of this forum) or should I move this to GE or OT?

Cliff

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Why not just use a computer mic input?
- Because I would have to leave the computer on all the time and would be burning a lot of power for that. Plus it would take hundreds of hours to learn to program the PC to do something like this.
It may not take you hundreds of hours to program something like this, but you have already spent hundreds of hours learning to program modern PCs.

Why not just capture the live streaming of NPR? -- Because that would require both high-speed internet access and keeping the PC on constantly. Plus learning how to program the PC to record between pre-set times and convert the results into an MP3 or ORG file.

A Creative Zen Vision W has a radio and can record.
-- I suspect that lawyer disease is the primary reason why there are no small cheap programmable radio recorders available. I ignore lawyers, but I don't do 100,000 unit production runs either.

I believe that an 8-bit AVR could act as a controller for various pre-made stand-alone items like a real-time IC, maybe an old cassette recorder, and an old walkman-style radio. I'm willing to develop for 20th-century technology, but everything has to be cheap. MP3 and USB would be nice, but it is not necessary to the fundamental function of a programmable radio recorder.

I don't think that internet access in the USA is going to get any better, just more expensive and unreliable. Lawyer disease is going to keep the big companies from offering any new amazing technologies at great prices (except for telephones). So innovative development will probably not be done or only done in DIY prototypes, with the schematics and source codes traded on focused but obscure web sites like this.

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You can get it via XM Satellite Radio:

http://www.bbc.co.uk/worldservice/programmeguide/schedule/date/100951:1/satellitecable/5746545/date/today

You could probably record it quite easily.

I listen to it at night via DAB or digital TV if I can't sleep and there isn't anything interesting on Radio 7.

Leon Heller G1HSM

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I have a Sansa View, I don't think it will do scheduling, but it will record from an FM station. They likely cost in the $100 ballpark, depending on what size you choose.
Playback wouldn't be as easy, you might have to use some software to chop it up into your 15 min sections and edit out the hours before and after.

Its better than spending the hours and hours trying to make an AVR do something it can't (at least not without a pile of extra devices).

"A common mistake that people make when trying to design something completely foolproof is to underestimate the ingenuity of complete fools."
-- Douglas Adams

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but everything has to be cheap. MP3 and USB would be nice, but it is not necessary to the fundamental function of a programmable radio recorder.

What's fundamental is CPU and storage bandwidth. If you were going to record raw PCM you'd need huge bandwidth and storage space. OTOH to MP3 or Ogg encode the audio in realtime you'd need a fiar slice of CPU power.

Given that you can get ARMs' for $1 these days and ones powerful enough to do the audio encode/decode in software rather than support silicon for under $10 (similar to top of the range AVRs) I'd be looking to use those. Of course there's also AVR32 - the AP7's can do 210MIPS on 150MHz - that should be enough power for audio codecs.