| 摘要 |
PURPOSE:To execute viewing and listening of a regular picture and voice of a program, by adding a key signal for descrambling a scrambled signal, to a terminal part of a specified program, and sending it out. CONSTITUTION:When a start signal S1 is detected from a signal applied to an input terminal 15, by a code discriminating circuit 22, each circuit is operated. Subsequently, when a key discriminating circuit S2 is detected and a kind of a key signal S5 of a program is discriminated, a signal S6 is written in a memory 23. Also, a synchronization separating circuit 20 samples signals VD, HD from a scrambled picture signal which is applied to a terminal 16, and drives a timing circuit 21. When this program ends, the memory 23 becomes a write mode of the key signal S5, a demodulating circuit 19 demodulates the FSK-modulated signal S5, and sets it as a key signal of a binary code. This signal is synchronized with a clock through the timing circuit 21, is written in the memory 23, and when write ends, a write stop signal is detected, and the write operation is stopped. |
