how it works

[dayoff]

how does traffic alerts on a rds radio work

[Skids]

You turn on Traffic Announcement. A local radio station broadcasts a code when its about to make traffic reports. Your radio, with TA switched on, picks up the code and retunes to that station so that you can hear the report. Then, after the report, the radio tunes back to the original station.

[ugly_bob]

That's the theory anyway ;-)

Anyone notice that often the reports start halfway through and/or finish before the traffic is done?

[:Ace:]

On our radio, the volume turns up really loud and doesn't allow you to turn it down. Also, the loudness doesn't turn down for ages after the traffic alert's finished.

[BillyBB]

To add to Skids answer. There is part of the radio signal which contains data rather than audio information. This tells your radio receiver what the station name is and can carry information such as the time. The presenter manually switches the 'Traffic' signal on when a bulletin is broadcast. Sometimes they forget but they can be fined if it is left on too long.

The volume setting is individual to your receiver, I can alter mine :-)

[WoWo]

At the radio end there is a scanning device which constantly moves up and down the radio frequencies looking for the TA code, when it finds one it switches the main raido frequency to that, then when the TA code goes off it reverts to the original.