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图文电视是利用场消隐期间有数十条黑扫描行不传送电视图像信号,而将文字和图形以数字信号的形式插入到电视信号的场逆程的空余行中,利用现有的电视发射系统发送,经带有图文电视解码器的电视机接收后,显示出文字或图形等信息的一种公共电视。目前,收看图文电视的方法主要有三种:一是用专门生产的带有图文电视接收功能的电视机,这类电视机国产的不多见,部分进口彩电虽有此项功能,但因接收图文电视制式不符合我国标准,因此无使用价值;二是采用图文接收机与普通电视机配合使用,但这种机外型接收机价格
Teletext is the use of vertical blanking period of dozens of black scan lines do not transmit television image signals, and the text and graphics in the form of digital signals into the television signal field reversal of free lines, the use of existing television transmission system Send, through the TV with a TV decoder decoder, showing a text or graphics and other information of a public television. At present, there are mainly three ways to watch teletext: one is specially produced televisions with teletext receiving function, which are rare in China and some imported televisions have this function Receive teletext system does not meet our standard, so no use value; the second is the use of teletext receivers and television sets in common use, but the appearance of this machine-type receiver