PURPOSE: To eliminate the effect of the crosstalk of the switch matrix by installing the additional signal generator which generates the signals of more than the crosstalk component to the selection switch device.

CONSTITUTION: Additional signal generator ASG is installed to the input or output side of PNPN-type semiconductor switch matrix SMX which gives a free connection release via control circuit CT to several units of input unit INn of the TV camera or the like as well as to several units of output unit OTn of the monitor TV or the like. And the control circuit gives a control so that the signal of more than the crosstalk component generated within the switch matrix which sent from ASG may be transmitted selectively to the output unit which is non-selected by the control signal. As a result, the crosstalk signals within the switch matrix are offset by the additional signals.