AM expanded band
The extended mediumwave broadcast band, commonly known as the [AM] expanded band, is a broadcast frequency allocation. It moves the upper limit of the AM bandplan from 1610 to 1700 kHz.
History
The band became officially available around 1993—only in ITU region 2 (North and South America). It is popular with micro-broadcasting for having less interference due to less signals than the standard/legacy AM band.
Though supported on most modern AM radio receivers sold in the Americas, this band is usually unavailable to older receivers except for those with substantial extended coverage. On such radios, the 1600-1700 segment was labeled "Police", since it was the original 'police radio' band. In the U.S., coverage on newer radios is mandated by the Federal Communications Commission (FCC), invoking the All-Channel Receiver Act.
Regional use
Americas
In the United States of America, the Federal Communications Commission voted to support an expanded band on April 12, 1990. The FCC granted "stereo preferences" to commercial broadcasters intending to use AM stereo when issuing licenses for the band. However, such stations have never been required to broadcast in stereo. With the evolution of the AM band becoming more talk radio than music, it is unlikely that the FCC would take any action against an extended-band station only broadcasting in monophonic sound.
