FM Broadcasting - Broadcast Bands

Broadcast Bands

Throughout the world, the FM broadcast band falls within the VHF part of the radio spectrum. Usually 87.5 to 108.0 MHz is used, or some portion thereof, with few exceptions:

• In the former Soviet republics, and some former Eastern Bloc countries, the older 65–74 MHz band is also used. Assigned frequencies are at intervals of 30 kHz. This band, sometimes referred to as the OIRT band, is slowly being phased out in many countries. In those countries the 87.5–108.0 MHz band is referred to as the CCIR band.
• In Japan, the band 76–90 MHz is used.

The frequency of an FM broadcast station (more strictly its assigned nominal centre frequency) is usually an exact multiple of 100 kHz. In most of the Americas and the Caribbean, only odd multiples are used. In some parts of Europe, Greenland and Africa, only even multiples are used. In Italy, multiples of 50 kHz are used. There are other unusual and obsolete standards in some countries, including 0.001, 0.01, 0.03, 0.074, 0.5, and 0.3 MHz. However, in order to minimise cross-channel interference, stations operating from the same or geographically close transmitters tend to keep to at least a 0.5 MHz frequency separation even when closer spacing is technically permitted, with closer tunings reserved for more distantly spaced transmitters as potentially interfering signals are already more attenuated and so have lesser effect on neighbouring frequencies.