| 摘要 |
PURPOSE:To automatically correct an H sag generated in the case of transmission/reception. CONSTITUTION:When a video signal subject to scrambling is transmitted, a reference signal of a predetermined level is inserted into the video signal for a vertical blanking period. A reference signal detection circuit 2 at a reception side detects the reference signal from the received video signal and a subtractor circuit 4 subtracts the detected reference signal from the video signal. The result of subtraction is descrambled. Thus, even when an H sag takes place in the video signal, it is automatically corrected and picture quality is not deteriorated. |
