PURPOSE: To clearly display a screen by generating an inside synchronizing signal from an inside synchronizing signal generating means when a non-signal state is detected, adding a tuning outputting signal to parts except for this inside synchronizing signal, and further adding a screen displaying signal.

CONSTITUTION: For example, the television signal of a tuned channel is in the non-signal state, because of the end of broadcasting time or the like. This non-signal state of the tuned channel is detected by a non-signal state detecting circuit 4. At that time, each inside synchronizing signal of a horizontal(H) pulse and a vertical(V) pulse is generated from an inside synchronizing signal generating circuit 5. Then, a changeover switch 3 is controlled by a CPU 6 so that an adder 8 can add the tuning outputting signal to the parts except for the inside synchronizing signal of the H pulse. The screen displaying signal from the CPU 6 is added to the first adding signal by a second adder 9. Thus, characters or the like to be displayed on the screen can be clearly displayed even when the television signal is in the non-signal state.