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The term telesoftware was coined by W J G Overington who first proposed the idea; it literally means “software at a distance” and it refers to the transmission of programs for a microprocessor or home computers via broadcast Teletext. Software bytes are presented to a terminal as pairs of standard teletext characters, thus utilizing an existing and well-proven broadcasting system.〔(Telesoftware: Using TELETEXT to support a home computer IEE Conference Publication 166, pp 273-276, September 1978 )〕 Pioneered in the UK during the 1970s and 80s. During that time, software was broadcast at various times on all of the (then) four terrestrial TV channels. Telesoftware was available on Ceefax (BBC teletext service) for the BBC Microcomputer via its teletext adapter from 1983–89 and was generally transmitted for a period of one week. Downloading could take place from Friday evening to the following Thursday evening. As the updating took place on a Friday, it was advised not to attempt to download software between 9am and 7pm on Fridays.〔(The micro user telesoftware guide )〕 Other channels provided for several other computers via a range of adapters and set-top boxes. The same delivery system was also used to deliver satellite weather images METEOSAT for download.〔 (BBC Announces Closure of Telesoftware Service (1989) )〕 Although none of the early telesoftware initiatives survived,〔(【引用サイトリンク】url=http://teletext.mb21.co.uk/gallery/ceefax/telesoftware/closure.html )〕 many of the techniques are now at the heart of the latest digital television systems. == References == 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「telesoftware」の詳細全文を読む スポンサード リンク
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