PURPOSE: To perform optimum tuning at a television side, by generating a video signal including a vertical synchronizing signal and an audio signal.

CONSTITUTION: An output clock pulse of a reference oscillator 40 is frequency divided at a frequency divider 54 and counted at a counter 66. Based on a timing pulse given with the counter output, the time of generation and width of a horizontal synchronizing signal are formed. That is, a white signal is formed at the period of horizontal synchronizing signal. Further, an output pulse of the frequency divider 54 is sequentially frequency-divided and 39-notation count outputs obtained from the count of the pulses at a counter 62 is taken as an audio output and a vertical synchronizing signal is formed from a timing pulse obtained as an output of a 16-notation counter 64. The white signal and the synchronizing signals are inputted to a wave converting circuit 44 and a video signal is obtained. Thus, the tuning operation with high accuracy can be performed easily.