Band I
Encyclopedia
Band I is the name of a radio frequency
Radio frequency
Radio frequency is a rate of oscillation in the range of about 3 kHz to 300 GHz, which corresponds to the frequency of radio waves, and the alternating currents which carry radio signals...

 range within the very high frequency
Very high frequency
Very high frequency is the radio frequency range from 30 MHz to 300 MHz. Frequencies immediately below VHF are denoted High frequency , and the next higher frequencies are known as Ultra high frequency...

 part of the electromagnetic spectrum
Electromagnetic spectrum
The electromagnetic spectrum is the range of all possible frequencies of electromagnetic radiation. The "electromagnetic spectrum" of an object is the characteristic distribution of electromagnetic radiation emitted or absorbed by that particular object....

.

Band I ranges from 47 to 88 MHz, and it is primarily used for radio
Radio
Radio is the transmission of signals through free space by modulation of electromagnetic waves with frequencies below those of visible light. Electromagnetic radiation travels by means of oscillating electromagnetic fields that pass through the air and the vacuum of space...

 and television
Television
Television is a telecommunication medium for transmitting and receiving moving images that can be monochrome or colored, with accompanying sound...

 broadcasting.

Channel spacings vary from country to country, with spacings of 6, 7 and 8 MHz being common.

Worldwide Usage

In the UK, Band I was originally used by the BBC
BBC
The British Broadcasting Corporation is a British public service broadcaster. Its headquarters is at Broadcasting House in the City of Westminster, London. It is the largest broadcaster in the world, with about 23,000 staff...

 for monochrome
Monochrome
Monochrome describes paintings, drawings, design, or photographs in one color or shades of one color. A monochromatic object or image has colors in shades of limited colors or hues. Images using only shades of grey are called grayscale or black-and-white...

 405-line television
Television
Television is a telecommunication medium for transmitting and receiving moving images that can be monochrome or colored, with accompanying sound...

; likewise, the French former 455-line (1937-1939) then 441-line (1943-1956) transmitter on the Eiffel Tower
Eiffel Tower
The Eiffel Tower is a puddle iron lattice tower located on the Champ de Mars in Paris. Built in 1889, it has become both a global icon of France and one of the most recognizable structures in the world...

 in Paris
Paris
Paris is the capital and largest city in France, situated on the river Seine, in northern France, at the heart of the Île-de-France region...

, 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 and still use Band I for 625-line
576i
576i is a standard-definition video mode used in PAL and SECAM countries. In digital applications it is usually referred to as "576i", in analogue contexts it is often quoted as "625 lines"...

 analogue television, first in monochrome and later in colour. This is now being gradually phased out with the introduction of digital television in the DVB-T
DVB-T
DVB-T is an abbreviation for Digital Video Broadcasting — Terrestrial; it 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 the UK in 1998...

 standard, which is not defined for VHF Band I.

In the United States, use of this band is for analog NTSC (ended June 12, 2009) and digital ATSC (current). Digital television has problems with impulse noise interference, particularly in this band.

The upper end of this band, 87.5 to 88 MHz, is the lower end of the FM radio 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
KSFH
KSFH FM 87.9 is a student radio station broadcasting an active rock radio format. Licensed to serve Mountain View, California, USA, the station's broadcast range is the San Francisco Bay Area. The station is owned by private school Saint Francis High School, and is completely run by its students,...

 is the only standalone station that uses 87.9 currently); 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
Pulse 87
Pulse 87 is an American television franchise that operated as a radio branding. The brand was formerly owned and operated by Mega Media. As of February 2010, the format was resurrected as an online internet station under new management following the bankruptcy and liquidation of its former...

's stations.

Europe

In many Western European countries the band is subdivided into three channels for television broadcasting, each occupying 7 MHz (System B).

Italy also uses 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
RAI
RAI — Radiotelevisione italiana S.p.A. known until 1954 as Radio Audizioni Italiane, is the Italian state owned public service broadcaster controlled by the Ministry of Economic Development. Rai is the biggest television company in Italy...

 in Torino in the Fifties. This channel now also widely used by private local stations will be discontinued with the coming of digital television.
Channel Frequency Range
E2 47-54 MHz
E2A 48.5-55.5 MHz
E3 54-61 MHz
E4 61-68 MHz
C 82.25-87.75 MHz


Some countries use slightly different frequencies or don't use Band 1 at all for terrestrial broadcast television. The fast growing of digital television in all European countries is accompanied by the progressive closedown of band I analog transmitters, e.g. former French-language Swiss Television transmitter at La Dôle
La Dôle
La Dôle is a peak in the Jura mountains in Vaud in western Switzerland rising to an altitude of 1677.2 meters. It is the second highest peak in the Swiss Jura, the highest being Mont Tendre....

 near Geneva
Geneva
Geneva In the national languages of Switzerland the city is known as Genf , Ginevra and Genevra is the second-most-populous city in Switzerland and is the most populous city of Romandie, the French-speaking part of Switzerland...

 on channel E4 or French analog transmitters used by Canal Plus for its Pay-TV VHF network, e.g. Besançon
Besançon
Besançon , is the capital and principal city of the Franche-Comté region in eastern France. It had a population of about 237,000 inhabitants in the metropolitan area in 2008...

 (Lomont
Lomont
Lomont is a commune in the Haute-Saône department in the region of Franche-Comté in eastern France. A high power sound broadcasting and television transmitting station is operated by TDF in the forest near the village to serve Besançon and the Franche-Comté county....

) and Carcassonne
Carcassonne
Carcassonne is a fortified French town in the Aude department, of which it is the prefecture, in the former province of Languedoc.It is divided into the fortified Cité de Carcassonne and the more expansive lower city, the ville basse. Carcassone was founded by the Visigoths in the fifth century,...

 (Pic de Nore
Pic de Nore
The pic de Nore at 1211 metres is the highest point in the Montagne Noire, on the border of the Aude and Tarn departments, near to the Parc naturel régional du Haut-Languedoc in southern France...

) both on French channel "L-3".

North America

The band is subdivided into five channels for television broadcasting, each occupying 6 MHz (System M).
Channel Frequency Range
1* 44-50 MHz
|
A2 54-60 MHz
A3 60-66 MHz
A4 66-72 MHz
|
A5 76-82 MHz
A6 82-88 MHz
A6A 81.5-87.5 MHz

Eastern Europe

Channel Frequency Range
R1 48.5-56.5 MHz
R2 58-66 MHz
R3 76-84 MHz
R4 84-92 MHz
R5 92-100 MHz
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