摘要 |
A television signal is distorted by passing it through a distortion amplifier which applies a Gaussian distortion curve to the signal. The curve has a maximum increase in amplitude of about 38 dB, which is about 30 dB with respect to the amplitude increase of the video carrier. The signal is further modified by the addition of gated jamming signals between the video and audio carriers. The jamming signals are present only during the horizontal and vertical blanking intervals and so do not affect the quality of the picture reproduced by the receiver. The distorted television signal is restored by applying a filter function which is the inverse of the distortion function. The gated jamming signals are removed by the restoring filter to a degree which permits the television receiver to read the horizontal and vertical sync signals and the color burst signal during the blanking intervals.
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