| 摘要 |
PROBLEM TO BE SOLVED: To provide a sound fault detection apparatus and an automatic sound switching apparatus which can simply and quickly determine a sound fault and quickly switch a defective system to a normal system. SOLUTION: The sound fault detection apparatus includes: a delay difference detection part 1 for detecting a transmission delay difference between two systems by using a duplex video signal; sound delay adjustment parts 2, 3 for adjusting the delay of sound demodulation signals of the two systems so that the delay difference detected by the delay difference detection part 1 is compensated; and a sound fault detection part 6 for detecting whether a sound from each system is silent or not according to outputs from the sound delay adjustment parts 2, 3 of the two systems. When only a sound signal from either one of both the systems is silent or when only a sound signal from either one of the systems determining that a fault is generated in the sound signal is silent, the sound fault detection part 6 determines the generation of a fault in the sound signal. COPYRIGHT: (C)2010,JPO&INPIT |
