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AM-RDS (ADDS) -and- C-QUAM Stereo?

J

JohnnyElectron

So iBiquity doesn't have every AM station throw their exciters in the trash heap, they've 'invented' an AM RDS system called 'ADDS' (AM's Attention Deficit Disorder Syndrom?). I'm wondering if this newly proposed ADDS AM RDS data system will be backwards compatible with HD radio receivers? That is, can you use an HD-AM tuner and receive analog audio with the "AM-RDS" (ADDS)? So that's quesiton #1 - is ADDS compatible with the $150 I spent on my HD tuner?

Also to note, this is a direct rip-off of the original Magnavox AM stereo system (and possibly a patent violation?) as Magnavox had a low-speed data system as part of the L-R pilot tone as part of their (original) FCC-approved analog AM Stereo system, so something old is new again!

Leonard Kahn is bound to pop-up too, as his CAM-D system also had a digital data stream on AM.

Now, the 'Rosetta Stone' to tie these all together: What I'm wondering: can the iBiquity exciters be programmed to generate the FCC-approved C-Quam analog AM stereo signal -AND- generate the 'RDS-data' (ADDS)? There were millions of these CQuam radios in cars, and this huge chunk of hardware could be used by 're-purposing' the iBiquity exciters for CQuam + ADDS. Some of the HD tuners WILL already receive CQuam, by accident, or by design, so it would a winning solution for the senior band to have decent NON-INTERFERING AM Stereo Audio - AND - Data!
Whaddayathink guys?
 
What do I think? If I were more technically inclined, I'd be clamoring to play with a box right now to generate analog A.M.S. & data! Just as a curiosity: could low-speed data be incorporated into any A.M. signal for simple text? Maybe just the callsign perhaps?
 
About a decade ago, there was another AM RDS system proposed, which did claim to be compatible with C-Quam. I'm not sure if it ever got patented, though.

As for repurposing the HD Radio exciters, anything is possible, as long as iBiquity (who is still supposed to be getting royalties for their use) allows it. But considering that many HD Radio receivers will decode C-Quam, and (IIRC) all of Motorola's patents on the system have expired, it should be a no-brainer to develop a C-Quam transmission mode.
 
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