| 摘要 |
<p>In a television receiver for selectively displaying a received television picture and an audio signal waveform on the screen of a cathode ray tube, an audio signal to be displayed is applied to a pulse generation circuit where it is converted to a waveform display pulse signal having the phase position corresponding to the audio signal and this waveform display pulse signal is applied through a video amplifier having a brightness control circuit to the cathode ray tube during the display of the audio signal waveform. In this case, the background level of the screen of the cathode ray tube is changed to be lowered so that a viewer can clearly see the audio signal waveform.</p> |
