| 摘要 |
PURPOSE:To uniform delay time characteristics as much as possible and to prevent deterioration in separation of an output audio signal, by arranging frequency converters in two-divided lines respectively and making decreases in frequency, and using band-pass filters with the same filter characteristics. CONSTITUTION:A signal from an input terminal 8 is branched to lines l2 and l3; the 1st frequency converter 16 is arranged at the front part of one line l2 and the 2nd frequency converter 17 is also arranged at the front part of the other line l3. The difference between the frequency f1 of the 1st sound carrier from the converter 16 and the oscillation frequency fL1 of the 1st local oscillator OSC1 is equalized to the difference between the frequency f2 of the 2nd sound carrier and the oscillation frequency fL2 of the 2nd local oscillator OSC2. The outputs of those converters 16 and 17 are applied to the 1st and the 2nd audio frequency discriminators 16 and 17 through BPF1-BPF2 with the same characteristics and their outputs are inputted to a dematrix circuit 15 to uniform delay time characteristics, preventing the separation of the output signal from deteriorating. |
