| 摘要 |
The present invention relates to a TV-signal transmission pay-TV-system which includes a transmitter, a number of system-subscribed receivers (13), a number of non-subscribed receivers (16), and a signal transmission medium (6, 7, 8) which connects the transmitter with respective receivers, wherein the transmitter is provided with, or coacts with a signal scrambling device and respective system-subscribed receivers are provided with or preceded by a signal-unscrambling device (14), wherein the signal-scrambling device and the signal-unscrambling device (14) are mutually so adapted as to unscramble a scrambled TV-signal transmitted from the transmitter and thereby regenerate a signal in its correct form, so as to form picture-correct lines and pictures and possibly also sound, while non-system subscribed receivers (16) receive distorted lines, pictures and possibly also distorted sound from the scrambled TV-signal, and wherein line signals according to a first system (MAC) are transmitted via the signal transmission medium. The system includes a first means (44) which functions to inhibit a first selected part ("a") of the line signals according to a second system (PAL) and a second means (44) functions to enable a second selected part to be applied to the line signals according to the PAL-system with a signal structure that conforms to the first system, (MAC). |
