| 摘要 |
In the NTSC, PAL and SECAM colour television system, the hue is coded by a phase angle of two alternating currents. Whilst the transmission is amplitude-modulated in the NTSC and in the PAL system, the SECAM system provides for frequency modulation. Time and again, phase errors occur in the transmitting and receiving devices and also on the transmission link. In the PAL system, such errors are compensated by complicated elaborate circuits. In the SECAM system, other errors occur due to the frequency modulation. The present invention avoids phase as a transmission feature. It transmits the quantities of hue and colour saturation digitally or by analog means by means of an alternating current. The error is not only avoided but bandwidth is also gained, particularly in the binary-coded alternating-current transmission.
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