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Band I is a range of radio frequencies within the
very high frequency Very high frequency (VHF) is the ITU designation for the range of radio frequency electromagnetic waves ( radio waves) from 30 to 300 megahertz (MHz), with corresponding wavelengths of ten meters to one meter. Frequencies immediately below VH ...
(VHF) part of the
electromagnetic spectrum The electromagnetic spectrum is the range of frequencies (the spectrum) of electromagnetic radiation and their respective wavelengths and photon energies. The electromagnetic spectrum covers electromagnetic waves with frequencies ranging fro ...
. The first time there was defined "for simplicity" in Annex 1 of "Final acts of the European Broadcasting Conference in the VHF and UHF bands - Stockholm, 1961". Band I ranges from 47 to 68 MHz for the European Broadcasting Area, and from 54 to 88 MHz for the Americas and it is primarily used for
television broadcasting A television network or television broadcaster is a telecommunications network for distribution of television program content, where a central operation provides programming to many television stations or pay television providers. Until the mid- ...
in compliance with
ITU Radio Regulations The ITU Radio Regulations (short: RR) is a basic document of the International Telecommunication Union (ITU) that regulates on law of nations scale radiocommunication services and the utilisation of radio frequencies. It is the supplementatio ...
(article 1.38). With the transition to digital TV, most Band I transmitters have already been switched off.


Television broadcasting usage

Channel spacings vary from country to country, with spacings of 6, 7 and 8 MHz being common. In the UK, Band I was originally used by the BBC for
monochrome A monochrome or monochromatic image, object or palette is composed of one color (or values of one color). Images using only shades of grey are called grayscale (typically digital) or black-and-white (typically analog). In physics, monochr ...
405-line The 405-line monochrome analogue television broadcasting system was the first fully electronic television system to be used in regular broadcasting. The number of television lines influences the image resolution, or quality of the picture. It was ...
television Television, sometimes shortened to TV, is a telecommunication medium for transmitting moving images and sound. The term can refer to a television set, or the medium of television transmission. Television is a mass medium for advertising, ...
; likewise, the French former 455-line (1937-1939) then 441-line (1943-1956) transmitter on the
Eiffel Tower The Eiffel Tower ( ; french: links=yes, tour Eiffel ) is a wrought-iron lattice tower on the Champ de Mars in Paris, France. It is named after the engineer Gustave Eiffel, whose company designed and built the tower. Locally nicknamed ...
in
Paris Paris () is the capital and most populous city of France, with an estimated population of 2,165,423 residents in 2019 in an area of more than 105 km² (41 sq mi), making it the 30th most densely populated city in the world in 2020. Si ...
, and some stations of the French monochrome 819-line system used Band I. Both 405-line and 819-line systems were discontinued in the mid-1980s. Other European countries used Band I for
625-line 625-lines is a standard-definition television resolution used mainly in the context of analog systems. It was first demonstrated by Mark Iosifovich Krivosheev in 1948. Analog broadcast television standards The following International Telecommun ...
analogue television, first in monochrome and later in colour. This was being gradually phased out with the introduction of
digital television Digital television (DTV) is the transmission of television signals using digital encoding, in contrast to the earlier analog television technology which used analog signals. At the time of its development it was considered an innovative adva ...
in the
DVB-T DVB-T, short for Digital Video Broadcasting – Terrestrial, is the DVB European-based consortium standard for the broadcast transmission of digital terrestrial television that was first published in 1997 and first broadcast in Singapore in Feb ...
standard, which is not defined for VHF Band I, though some older receivers and some modulators do support it. In the United States, use of this band is for analog
NTSC The first American standard for analog television broadcast was developed by National Television System Committee (NTSC)National Television System Committee (1951–1953), Report and Reports of Panel No. 11, 11-A, 12–19, with Some supplement ...
(ended June 12, 2009) and digital ATSC (current). Digital television has problems with impulse noise interference, particularly in this band.


Europe

In European countries that used System B for television broadcasting, the band was subdivided into three channels, each being 7 MHz wide: Italy also used a "outband" "channel C" (video : 82.25 MHz - audio : 87.75 MHz). It was used by the first transmitter brought in service by the RAI in
Torino Turin ( , Piedmontese: ; it, Torino ) is a city and an important business and cultural centre in Northern Italy. It is the capital city of Piedmont and of the Metropolitan City of Turin, and was the first Italian capital from 1861 to 1865. T ...
in the Fifties which was previously used in WW2 by the US to broadcast
NTSC The first American standard for analog television broadcast was developed by National Television System Committee (NTSC)National Television System Committee (1951–1953), Report and Reports of Panel No. 11, 11-A, 12–19, with Some supplement ...
TV on channel A6 for military purposes, later donated to Italy, it had its video carrier shifted 1 MHz lower to accommodate the System B standard. This channel was also widely used by private local stations until the switch over to
DVB-T DVB-T, short for Digital Video Broadcasting – Terrestrial, is the DVB European-based consortium standard for the broadcast transmission of digital terrestrial television that was first published in 1997 and first broadcast in Singapore in Feb ...
. Some countries used slightly different frequencies or don't use Band 1 at all for terrestrial broadcast television. The fast growing of digital television as well as the susceptibility of this band to interference during E skip events in all European countries was accompanied by the progressive closedown of band I analog transmitters from 2006 to 2020.


Russia and other former members of OIRT

In the countries that use System D television broadcast system, the channel allocation in the VHF-I band is as follows: Russia switched off Band I transmitters in early 2020. Ukraine, Moldova, Kazakhstan and a few other countries still broadcast analog TV on Band I in 2020.


North America

The band is subdivided into five channels for television broadcasting, each occupying 6 MHz (
System M A system is a group of interacting or interrelated elements that act according to a set of rules to form a unified whole. A system, surrounded and influenced by its environment, is described by its boundaries, structure and purpose and expresse ...
). Channel 1 is not being used for broadcasting.


FM radio usage

The upper end of this band, 87.5 to 88 MHz, is the lower end of the
FM radio FM broadcasting is a method of radio broadcasting using frequency modulation (FM). Invented in 1933 by American engineer Edwin Armstrong, wide-band FM is used worldwide to provide high fidelity sound over broadcast radio. FM broadcasting is cap ...
band. In the United States, the FCC will occasionally issue a license for 87.9 MHz (though it only does so on rare occurrences and special circumstances; KSFH was the most recent standalone station to use 87.9); 87.7, which is approximately the same frequency as the audio feed of channel 6, is used by some television licenses to broadcast primarily to radio, such as Pulse 87's stations. In Japan and some former Soviet republics frequencies lower than 87 MHz are still used for the
FM broadcast band The FM broadcast band is a range of radio frequencies used for FM broadcasting by radio stations. The range of frequencies used differs between different parts of the world. In Europe and Africa (defined as International Telecommunication Union ( ...
. In Brazil, with the phasing out of the
PAL-M PAL-M is the analogue TV system used in Brazil since 19 February 1972. At that time, Brazil was the first South American country to broadcast in colour. Colour TV broadcast began on 19 February 1972, when the TV networks Globo and Bandeirantes t ...
analog broadcasts, AM radio stations has being migrated to a new
FM radio FM broadcasting is a method of radio broadcasting using frequency modulation (FM). Invented in 1933 by American engineer Edwin Armstrong, wide-band FM is used worldwide to provide high fidelity sound over broadcast radio. FM broadcasting is cap ...
band between the frequencies from former analog TV channels A5 and A6 (76.1Mhz to 87.5Mhz) called Extended FM or e-FM.


Amateur radio and TV DX

The
6-meter band The 6-meter band is the lowest portion of the very high frequency (VHF) radio spectrum internationally allocated to amateur radio use. The term refers to the average signal wavelength of 6 meters. Although located in the lower portion of t ...
(50 MHz) and the 4-meter band (70 MHz) are used by
radio amateurs An amateur radio operator is someone who uses equipment at an amateur radio station to engage in two-way personal communications with other amateur operators on radio frequencies assigned to the amateur radio service. Amateur radio operators ha ...
. Short wave-like propagation is only possible under special circumstances, including frequent E skip events in the summer season. This leads to strong signals in the 800–2,000 km range allowing the reception of distant TV stations (TV DX). World wide connections are possible but remain a challenge on these frequencies.


See also

*
Television channel frequencies The following tables show the frequencies assigned to broadcast television channels in various regions of the world, along with the ITU letter designator for the system used. The frequencies shown are for the analogue video and audio carriers. ...


References

{{Audio broadcasting Broadcast engineering Radio spectrum