| 摘要 |
PURPOSE:To improve the reproduced S/N in case of reproducing of the first or the second tape mechanism b inserting a switching circuit to each of output lines of equalizer amplifiers of the first and the second tape mechanisms. CONSTITUTION:When the first tape mechanism A is set to the reproducing state, leaf switches S3 and S2 are turned on, and a motor 26 is rotated, and power is supplied from a power source 25 to the amplifier. At this time, equalizer amplifiers 5 and 6 for the mechanism A and equalizer amplifiers 7 and 8 for the second tape mechanism B are operated simultaneously. However, since transistors TRs Q28, Q30, Q34 are inserted to outputs of amplifiers 5-8, TRs Q28 and Q30 are turned on when switches S2 and S3 are turned on, and outputs of amplifiers 5 and 6 are trasmitted to amplifiers in the succeeding stage. Meanwhile, TRs Q32 and Q34 are not turned on, and outputs of amplifiers 7 and 8 are not transmitted to amplifiers in the succeeding stage. Consequently, the oise outputs of respective equalizer amplifiers are not added in case of reproducing of the mechanism A or B.
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