随着小型电视转播台的不断出现,录象信号与转播信号分别送进差转机的转换是一个急待解决的问题。过去是靠人为拔动插头来实现转换,这样不但要造成接触不良等故障,而且当电视台转换节目内容时,电视观众不但在屏幕上会看到一片漆黑,而且也会听到较强的噪声。为此,我们设计并安装了一 With the continuous appearance of small-scale television relay stations, the conversion of video signals and broadcast signals into differentiators is an urgent issue to be solved. In the past, people switched their plugs to make the switchover. This would not only cause troubles such as poor contact, but also changed the content of television programs so that television viewers could not only see the screen dark but also hear strong noises. To this end, we designed and installed one