| 摘要 |
PURPOSE:To improve the efficiency of switching by skipping automatically an input terminal to which no input line is connected and advancing the mode by one in a television receiver having plural video input terminals. CONSTITUTION:When there are input terminals not connected with any input line among plural video input terminals, a switch 4 is in the closed state and a voltage is inputted to a terminal 2 of a changeover switch 16 while it is delayed for a prescribed time. Thus, an output of an output terminal 17 goes to a high level and an output of an AND circuit 21 is applied to an input control terminal 7 of a counter 20 through a diode 24. Thus, a low tension pulse is inputted to the counter 20, the mode is advanced automatically by one. |
