Band I

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Band I is the name of a radio frequency range within the very high frequency part of the electromagnetic spectrum.

Band I ranges from 47 to 88 MHz, and it is primarily used for radio and television broadcasting.

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

Broadcast Television Usage[edit]

In the UK, Band I was originally used by the BBC for monochrome 405-line television;[1] likewise, the French former 455-line (1937-1939) then 441-line (1943-1956) transmitter on the Eiffel Tower in Paris, 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 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 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.

Europe[edit]

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 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 near Geneva on channel E4 or French analog transmitters used by Canal Plus for its Pay-TV VHF network, e.g. Besançon (Lomont) and Carcassonne (Pic de Nore) both on French channel "L-3".

North America[edit]

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[edit]

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

FM Radio Usage[edit]

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 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's stations.

See also[edit]

References[edit]

  1. ^ Paulu, Burton (1981-10-01). Television and Radio in the United Kingdom. U of Minnesota Press. p. 91. ISBN 9780816609413. Retrieved 11 April 2012.