| 摘要 |
PURPOSE:To supply power to a 1st converter only when a receiver incorporated in a distributer and at least one of plural receivers connecting to the relevant receiver are in operation. CONSTITUTION:When an H level switching signal is fed to a switching signal input terminal 7a of a TV 10, a DC power supply circuit PS3 is activated, a DC voltage 15V is fed to a distribution output terminal 9b of a VTR 8, the voltage is changed by resistors R5, R6 and fed to an input port 11a of a microcomputer 11 as an H level control signal. Conversely, in the case of an L level switching signal, an L level control signal is applied thereto. On the other hand, the VTR 8 gives an H or L level switching signal to the microcomputer 11 as a control signal and when an H level control signal of at least one of the VTR 8 and the TV 10 is fed to the relevant microcomputer 11, an H level switching signal is fed to the DC power supply circuit PS2, which is operated to supply power to a 1st converter 2. |
