FIELD: computer engineering. SUBSTANCE: circuit has BNC signal terminal, D-sub signal terminal, video signal switch which receives video signals from BNC signal terminal and D-sub signal terminal, video signal processor which receives one of video signals from BNC signal terminal and D-sub signal terminal, received video signal, which is selected in video signal switch, synchronization signal switch which receives V and H synchronization signals from D-sub signal terminal, detector, which receives detection signal representing connection state between D-sub signal terminal and personal computer, microcomputer which is connected to output of detector generating control signal, switch controller which receives control signal, which controls video signal switch and synchronization signal switch. EFFECT: possibility of automatic switch of input signal of monitor. 8 cl, 7 dwg
