RDS
I was on a little road trip with a friend, who had just installed a new multi-use "entertainment center" in his car. The device includes a DVD player, AM/FM receiver, and Bluetooth-enabled display and player for iPhone and iPod (or similar devices).
While fiddling around with the setup, we discovered a featured called "RDS," which was a simple toggle - on or off.
Having no idea what this was, we investigated, only to find - as happens more and more often these days - a whole world of information hidden just below the surface of a new device.
RDS - Radio Data System - is known in the US as RBDS (Radio Broadcast Data System), and it's anything but new.
The standard began as a project of the European Broadcasting Union (EBU) in the early 80s, but has since become an international standard of the International Electrotechnical Commission (IEC).
Says Wikipedia, "Both (RDS and RBDS) use a 57kHz subcarrier to carry data at 1187.5 bits per second. The 57kHz frequency was chosen for being the third harmonic of the pilot tone for FM stereo, so it would not cause interference or intermodulation with it, or with the stereo difference signal at 38 kHz (the second harmonic). The data format utilizes error correction. RDS defines many features including how private (in-house) or other undefined features can be "packaged" in unused program groups."
Yipe... ok, all that means is that along with the radio signal, you'll get supporting data that provides further information about what you're hearing on the radio - things like the name of the song being played, or the artist. We're now familiar with this type of information being displayed when listening to satellite radio, and with newer receivers, on our standard radios as well.
As part of the setup, once RDS was enabled (we assumed that this particular device we were working with had probably been made for European consumption, or it would have offered the American-standard RBDS), we were given more arcane codes: TA, PTY, and AF.
Huh?
While there are other selections, these three are fairly standard data types.
TA is basically Traffic Advisory. With RDS enabled, pressing the "TA" selector will cause the radio to scan the stations looking for an active travel advisory. The same is true if AF is selected - only this time, it will scan for Alternative Frequencies (This allows a receiver to re-tune to a different frequency providing the same station when the first signal becomes too weak (e.g. when moving out of range)).
PTY is Program Type - a coding of up to pre-defined program types allowing users to find similar programming by genre.
I couldn't help but think back, confronted with such a wealth of information about what we were listening to, to the bad if romantic old days of radio, when you'd sit and patiently micro-adjust the dial of your radio, hoping to catch a signal from a nearby station - or even a far distant one (easier on hot summer nights). And then you'd listen carefully til you recognized an announcer's voice, or perhaps caught the callsign during station identification.
A few moments of nostaligia... and then, ok, there are benefits to the Brave New World, after all!
While fiddling around with the setup, we discovered a featured called "RDS," which was a simple toggle - on or off.
Having no idea what this was, we investigated, only to find - as happens more and more often these days - a whole world of information hidden just below the surface of a new device.
RDS - Radio Data System - is known in the US as RBDS (Radio Broadcast Data System), and it's anything but new.
The standard began as a project of the European Broadcasting Union (EBU) in the early 80s, but has since become an international standard of the International Electrotechnical Commission (IEC).
Says Wikipedia, "Both (RDS and RBDS) use a 57kHz subcarrier to carry data at 1187.5 bits per second. The 57kHz frequency was chosen for being the third harmonic of the pilot tone for FM stereo, so it would not cause interference or intermodulation with it, or with the stereo difference signal at 38 kHz (the second harmonic). The data format utilizes error correction. RDS defines many features including how private (in-house) or other undefined features can be "packaged" in unused program groups."
Yipe... ok, all that means is that along with the radio signal, you'll get supporting data that provides further information about what you're hearing on the radio - things like the name of the song being played, or the artist. We're now familiar with this type of information being displayed when listening to satellite radio, and with newer receivers, on our standard radios as well.
As part of the setup, once RDS was enabled (we assumed that this particular device we were working with had probably been made for European consumption, or it would have offered the American-standard RBDS), we were given more arcane codes: TA, PTY, and AF.
Huh?
While there are other selections, these three are fairly standard data types.
TA is basically Traffic Advisory. With RDS enabled, pressing the "TA" selector will cause the radio to scan the stations looking for an active travel advisory. The same is true if AF is selected - only this time, it will scan for Alternative Frequencies (This allows a receiver to re-tune to a different frequency providing the same station when the first signal becomes too weak (e.g. when moving out of range)).
PTY is Program Type - a coding of up to pre-defined program types allowing users to find similar programming by genre.
I couldn't help but think back, confronted with such a wealth of information about what we were listening to, to the bad if romantic old days of radio, when you'd sit and patiently micro-adjust the dial of your radio, hoping to catch a signal from a nearby station - or even a far distant one (easier on hot summer nights). And then you'd listen carefully til you recognized an announcer's voice, or perhaps caught the callsign during station identification.
A few moments of nostaligia... and then, ok, there are benefits to the Brave New World, after all!
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