DAB+ technology allows radio reception in the tunnels for all available DAB channels and not just for a few channels. Also, the DAB technology makes it possible to break into the broadcasts of all channels and allows the authorities to communicate with all road users, that is listening to radio in the tunnel, with both traffic information and emergency messages.
If the focus should be on the message that is broadcasted in the tunnel, the sign should be turned on when such a message is broadcasted. In addition if you use a blinking light on the top of the sign, the sign will get the necessary attention. This solution has just been decided and installed in several tunnels in Norway.
The sign are using a message icon instead of FM, in addition to the word "Radio". This gives a clear indication that there is messages on the radio, and you should turn on the radio and listen.
Norway is the first country in the world that shut down national and regional FM broadcasting in favour of DAB technology.
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