PURPOSE: To know identification for the visitor by securing the blinking for a fixed time for the display screen of the TV picture receiver via the visitor signal.

CONSTITUTION: With push of the switch of slave unit 2 of the chime, the potential difference is caused between master unit 1 and the double lines of connection line 8. This signal is supplied to TV picture receiver 3 through connection line 6. Connection line 7 transmits the power source, the earth line, the vertical oscillation signal, the oscillation signal and the blanking pulse to visitor signal display circuit 4 from chassis 5, and also transmits the visitor signal to chassis 5 from circuit 4 as well as transmits the signal sent from line 6 to circuit 4. When the signals are applied to circuit 4 from chimes 1 and 2, the visitor signal turns to the blinking signal for several seconds to be applied to the G-Y output signal of chassis 5. And thus the rectangular display is given to part of the display screen of TV picture receiver 3.