The number of radio stations has increased significantly during the past decades. When commercial radio operations were introduced in 1985, commercial radios had 18 transmitters. Now they have more than 900 transmitters. Combined with Yle's transmitters, there are more than 1,000 transmitters altogether.
Almost all radio broadcasting is based on ultra-short waves and frequency modulation (FM). AM broadcasting using short, medium and long waves is practically history. Currently there is only one AM radio station in Finland.
Radio coverage and receivers
When designing radio coverage areas, it is assumed that consumers use a rooftop antenna for the reception. If you live outside the coverage areas, good radio reception cannot be guaranteed.
In practice, you can also use portable radios or car radios and get good radio reception within almost the entire coverage area. However, they are more sensitive to fading caused by natural obstructions or structures of a building. A portable radio may work well in one room but the reception can still be poor on the other side of the wall.
You can listen to some radio stations far away from the transmitter outside their actual coverage area. As the number of radios increase, new transmitters may make listening to the existing stations outside their actual coverage area more difficult.