HD radio schematic

[bacon665]

Anyone have one? ive spent many hours on google and forums looking for a schematic to decode hd radio. for inclusion in an all in one amp.
i seen one and could slap myself for not saving the images.

Thnx

 

[gmarsh]

You won't be able to build one - the hardware requirements (OFDM decoding, tons of processing) are similar in complexity to what you find in a digital cellphone.

Even if you did pull off the hardware, you won't be able to write the software required to do the decoding because the specs aren't out there. It's a proprietary system which involves a unique audio codec.

Best advice I can give you is to hack apart a commercial receiver and start looking for I2S.

 

[bacon665]

If theyre being manufactured there has to be a way to get ahold of an IC or the stuff needed. but i guess ill just wait 10 years on that board until the stuff is available.

 

[paulb]

If theyre being manufactured there has to be a way to get ahold of an IC or the stuff needed.

Some ICs cannot be purchased and never will be able to be without direct arrangement with the manufacturer. Speaking from personal experience.

 

[bacon665]

do you have any experience with pioneer ?

Im thinking about contacting them later.

 

[gmarsh]

Another gotcha: you need to pay an iBiquity license fee to build a HD Radio receiver.

Again, you're better off dismantling an existing radio.

 

[rwyarbrough]

HD Radio Receiver IC

HD Radio base-band receiver - STMicroelectronics



STA680Q pdf, STA680Q description, STA680Q datasheets, STA680Q view ::: ALLDATASHEET :::

 

[gmarsh]

Yeah, that chip will do the demodulation for you. Hardware wise you'll need an RF/IF receiver and an ADC/baseband processor (with suitable oscillator) to feed the digital baseband into that chip.

Biggest hurdle you'll run into is finding code to shove in the SPI flash, ST won't give it away. Your best bet there is to find an existing receiver and rip its SPI code, then sniff the I2C interface to find out how to control the thing.

But I still maintain your best bet is to buy an existing/functional HD Radio receiver and go looking for I2S.

 

[bacon665]

Yea, now instead of being a starving student im a full time student plus full time employee and i have to do clinicals and side mechanic work i dont have time to finish the projects i started (story of peoples life eh?)

 

[stratus46]

HD Radio base-band receiver - STMicroelectronics



STA680Q pdf, STA680Q description, STA680Q datasheets, STA680Q view ::: ALLDATASHEET :::

And if it's like the analog Dolby processing chips, you could get the data sheet but not the chip.

G²

 

[SoNic_real_one]

ALL the proprietary codecs/decoders require some kind of licensing fee and legal agreement of non-disclosure for software. Code is protected by copyright and DMCA even (when it is encrypted in a chip).
That's why all the media jumped in the digital bandwagon, not for our benefit (they say that they want to provide "better" content) but to close the "analog hole".

 

[dangus]

And if you do get the chip, it'll have umpteen tiny legs, so a home-made circuit board will be out of the question. And after all that, you're just getting lossy digital audio. While the highest bitrates may sound pretty good, I suspect that few stations will actually devote all the bandwidth to a single channel. They'll probably cram in some pay services like several channels of Muzak to defray the cost of going HD.

There seems to be some JVC HD radios for $45 on eBay at the moment, and that's buy-it-now price.

HD Radio - Wikipedia, the free encyclopedia