| 摘要 |
PURPOSE:To use only one automatic discrimination circuit of the television broadcast system, to make the circuit small and to reduce discrimination time by using a 1st demodulation circuit so as to demodulate a broadcast signal of each reception channel in advance and discriminating the television broadcast system. CONSTITUTION:First demodulation circuits 5A, 27 demodulate the broadcast signal of each reception channel sequentially, a discrimination circuit 32 discriminates the television broadcast system of each reception channel, the result is stored in a memory 33 and 2nd demodulation circuits 5B, 28 read the television broadcast system of a desired reception channel from the memory 33 and demodulate it. Thus, it is not required to provide a discrimination circuit of the television broadcast system for the 2nd demodulation circuits 5B, 28. Moreover, since the television broadcast system is stored corresponding to each reception channel in the memory 33, the television broadcast system is discriminated by having only to read the television broadcast system at the reception channel changeover. Thus, the discrimination time is reduced. |
