PURPOSE: To apply a video signal of an optimum aspect ratio to any of a receiver compatible with aspect ratios of 4:3 and 16:9 and a receiver compatible with aspect ratio of 4:3 by incorporating an aspect ratio converter converting an aspect ratio of a video signal from 16:9 into 4:3 and a load detector to the controller.

CONSTITUTION: A load detector 3 gives a control signal in response to a video signal with an optimum aspect ratio to a control signal output terminal 5 to detect whether or not the control signal output terminal 5 and a control signal input terminal 6 are connected. When it is detected that the control signal output terminal 5 and the control signal input terminal 6 are connected, a switch S1 is controlled to select a terminal A and a control signal is fed to a video signal processing circuit 4. The video signal processing circuit 4 receives the video signal with an aspect ratio in response to the control signal. When it is detected that a conventional receiver is connected and the control signal output terminal 5 and the control signal input terminal 6 are not connected, the switch S1 is controlled to select a terminal B.