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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== In the UK, Band I was originally used by the BBC for monochrome 405-line television; 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. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Band I」の詳細全文を読む スポンサード リンク
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