Adaptors for DAB + can transmit on FM far beyond the inside of car.
DAB adaptors can be used in cars that originally lack a built-in DAB radio. They receive the DAB signal and transmit to the car stereo system either via line input (AUX) or via the adaptor that transfers the sound to the car stereo via FM. Many DAB adaptors can connect to someone else's phone call in the car. Now it turns out that this can happen even at relatively long distances from the car. Now many in cars rather switch to local radio on FM or listen on-line than trying to get a decent reception via an adaptor.
DAB adaptors have been the recommended solution for Norwegians who do not want to change the entire radio system in the car, but the adaptors have a major disadvantage. If you connect the mobile phone to the system, everyone can hear the conversation. These adaptors transmit a radio signal that basically only reaches 3 to 5 meters. Telenor has now tested adaptors that can transmit much longer than that.
We performed a very simple test and then we could "listen" the conversation in a radius from zero to 200 meters from the DAB adapter, says Deputy Director Bjørn Amundsen in the telecom company Telenor. I'm not sure how much output power the FM transmitter's DAB adaptor was built for, but it was probably bigger than allowed. But then many DAB adaptors have stronger transmitters than allowed 50 nanowatt, Amundsen explains to the newspaper Moss Avis.
Another problem is that many people use the preset FM frequency DAB adaptor transmits. That means problems for being close to another car with an adaptor transmitting on the same frequency.
The safest thing to do is to ignore DAB and listen to local radio, which continues to broadcast on FM in Norway.
The telecom authority Nkom warns that they will intervene in violation of transmission regulation. Nkom points out that importers and distributors of radio equipment responsible for the equipment they import or sell comply with the European regulations.
Nkom clarifies that before the radio equipment becomes available on the Norwegian market, the manufacturer must ensure that the equipment has been subject to a conformity assessment. This means that the equipment has been tested according to current standards and there is technical documentation that shows that the equipment complies with the basic requirements of the Radio Equipment Directive, which applies throughout the EU/EEA.
The output power must not exceed 50 nW (nanowatt), which provides a limited reach (up to 10 meters), but should be sufficient for the transmission to be captured by the car's FM radio.
Read more: radionytt.no
DAB-adapter kan avlyttes på 200 meters avstand
During the last two years during the transition of national radio from FM there has been bad reviews for several different types of DAB adaptors marketed in Norway. Some have got a rubbish stamp. Among other things, it has been found that some are not working to receive and transmit traffic alerts (as RDS on FM). Adaptors are also difficult to install correctly, especially antenna systems in order to get a workable reception quality.
Adaptors can also be difficult to tune while driving and car organisations have warned that the operation could compromise road safety.
There is no real global market for DAB adaptors. The market is highly concentrated to Norway - the only country in the world forcing listeners to switch-over from FM. Sales in other DAB countries, such as Denmark and the UK, are very limited. This is believed to be due to the fact that FM radio is still the dominant listening platform in these countries as well. This limits the need to also listen to DAB radio in the car.
Today, as an alternative to FM, many listeners go for car radio via mobile broadband on a smartphone or built-in on-line systems as Apple CarPlay, rather than buying a DAB adaptor. Still there are approx. 2 million cars in Norway not equipped with DAB radio
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