| 摘要 |
PURPOSE:To recognize the normal operation of a diversity reception device by generating and displaying a void period when any antenna is not connected to a TV receiver when a channel is switched. CONSTITUTION:A flicker display permission flag 11, a flicker display processing flag 12, a timer counter 13, a counter without vertical synchronism 14 and a display recognition counter 15 are provided for RAM 10 connected to CPU in the device. When vertical synchronous interruption does not exist for prescribed time based on vertical interruption/timer interruption count values at every prescribed time after the flag 12 is reset, the flag 11 is set and the various counters are cleared, the channel is judged to be switched and the flag 11 is reset. Then, the antenna is set to a non-connected state for prescribed time as against the TV receiver. Thus, void for prescribed length in one scanning line is generated in the TV receiver, and the normal operation can be recognized. |
