| 摘要 |
PURPOSE:To reduce adverse effect due to misjudgement by taking out the level difference of each input audio signal and delaying the output signal after level decision based on the signal with this level difference, and turning this delay output signal to be a stereo/monoral decision signal. CONSTITUTION:An attenuator 32 is inserted and connected to the input side of the sum signal (L+H) components of a comparison device 31. The output signal from the comparison device 31 is sent to a delay circuit 34. In this delay circuit 34, a delay output signal (l) from a comparison device 39 indicates stereo at the time of 'H' and monoral at the time of 'L' respectively, to be sent to a three input AND gate 27. The 'H' is outputted from an output terminal 29 as the stereo only when all the stereo/monoral decision due to the stereo pilot signal at the time of TV broadcasting, the output signal from a hysterisis decision circuit part 20, and the output signal from a delay circuit 34 are decided as stereo H from the three input AND gate 27. |
