The RDS function, which stands for "Radio Data System", is a system that enriches conventional analogue FM broadcasts with additional digital information. In practice, this means that an RDS-enabled tuner not only displays the frequency of the station, for example 94.6 MHz, but also its name, for example "Radio Magazine". In addition to the station name, RDS can also transmit additional text messages, known as Radiotext. These messages often contain the name of the artist currently playing and the title of the song, the title of the current programme or a short message. Another option is the PTY or "Programme Type" function, which allows you to search for stations by broadcast genre. This allows the tuner to automatically tune in stations that broadcast, for example, news, pop music or rock. The RDS system also often includes an AF or "Alternative Frequencies" function. If the tuner detects that the signal of the station you are listening to is fading, it will automatically try to find a stronger frequency on which the same station is broadcasting and smoothly switch to it, ensuring stable listening. Some tuners also use RDS to automatically set the exact time and date thanks to the CT function, "Clock Time", which stations broadcast along with their programme.
