AM expanded band

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9 kHz
spacing
10 kHz
spacing
1611 1610
1620 1620
1629 1630
1638 1640
1647 1650
1656 1660
1665 -------
1674 1670
1683 1680
1692 1690
1701 1700

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[edit]

The band became officially available around 1993—only in ITU region 2 (North and South America). It is popular with micro-broadcasting for having slightly better sound reproduction characteristics than the standard 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[edit]

Americas[edit]

In the United States of America, the FCC granted "stereo preferences" to commercial broadcasters intending to use AM stereo when issuing licenses for the band.[citation needed] 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.[original research?]

Expanded band stations generally[vague] broadcast omnidirectionally with ten kilowatts of power in the daytime and one kilowatt at night—except for stations that use antennas with higher than normal efficiency or those multiplexed with an existing station on a different frequency. In those cases, they may[vague] be only authorized to less than one kilowatt at night (generally limiting such stations to 281 millivolts per meter per kilowatt at one kilometer, the minimum efficiency for a Class B station.[citation needed]).

Because 1610 kHz (the top or right-most channel on analog radios) had previously been reserved for Travelers' Information Stations (TIS) as 530 kHz — the bottom or left-most channel — still is, some TIS stations were displaced for new expanded-band stations .[citation needed] There are no AM stations in the United States licensed to 1610 kHz [1]

While 1710 kHz appears on many radios, it is unused even by TIS stations, except for a group (WQFG689) licensed with a waiver to the County of Hudson. This is due to the fact that aeronautical radionavigation may use 1708 kHz,.[2]

Greater Europe[edit]

Although the extended band is not officially allocated in Europe, it is used by Vatican Radio and a number of "hobby" pirate radio stations, particularly in the Netherlands, Greece, and Serbia.

Australasia[edit]

In Australia, many[vague] commercial radio broadcast licences have been authorised for the extended band.

However, they have restrictions not placed on licences for the standard mediumwave band: e.g. 5 kHz bandwidths and type H3E emissions, as used by CHU in Canada on shortwave, without reducing sound quality.

The vast majority of licences have never been used.[citation needed] Due to a number of factors[vague], few Australian stations in this band have many listeners.[citation needed]

The Philippines[edit]

In the Philippines, the first AM expanded band radio station in low power format broadcasting in Marikina City is DZBF DEL Radio - Radyo Marikina 1674 kHz started in July 25, 1996.

References[edit]

External links[edit]