INFORMATION ON TRAFFIC PROBLEMS is transmitted by many radio stations as part of their regular programs.The problem for the motorist is that his car radio must be tuned to the right station, and that he must listen constantly to the program of that station. He cannot even play a cassette.FM stations using the ARI system transmit inaudible signals that 1) help to identify the station, and the area for which traffic bulletins are transmitted, or even tune the car radio automatically to that station 2) turn up the volume of the receiver during the traffic message to a preset level to ensure that the message is heard 3) stop the cassette play, switch over to the traffic bulletin, and switch back to cassette after the message.Due to simplicity, efficiency and low cost the ARI system has been very successful over the last ten years. Virtually every car radio sold in the ARI countries Germany, Austria, Switzerland, Luxembourg in the past 5 years was equipped with an ARI decoder. Now the ARI system is also operational in USA. After two years of silent tests and investigations the system started officially in USA on April 12, 1983, with four stations in New York, and is now being expanded over the whole country.