| 摘要 |
PURPOSE:To generate a timing signal corresponding to all standard TV system by outputting either of a thinning signal or a nonsignal and generating a prescribed signal from the counted result of an output signal. CONSTITUTION:With a horizontal blanking signal supplied from a synchronizing signal generator 1, a counter circuit 2 counts the number of auxiliary carrier signals SC only in an effective scan period. A comparison circuit 3 compares the number outputted from the circuit 2 with a previously decided set value. If they coincide, it generates a coincidence signal Gate and outputs a coincidence signal whenever the number becomes the multiple of 5. A switch circuit 8 changes a switching signal and decides whether or not to connect the signal Gate by the standard TV system. If the signal Gate is outputted, a gate circuit 4 thins a signal SC' and supplies the thinned signal SC to a counter circuit 5. A prescribed signal is generated from the circuit 5 and the timing signal corresponding to all the standard TV systems can be generated.
|
