| 摘要 |
PURPOSE:To eliminate the need for a new external changeover switch by using a 2-channel preamplifier switching means included in a conventional 2-channel integrated circuit and a switching means for switching a main signal and a delay signal at dropout to switch sequentially a 4-head reproducing output. CONSTITUTION:In obtaining a reproducing signal from a head 1, an output of a preamplifier 6 passes through a changeover switching means 10 when a 30Hz switch signal SW 30 is low and is inputted to an AGC circuit 12. The switch changeover signal SW 30 goes to high level during the reproducing period of a head 2, the switch 10 in the 1st integrated circuit 5a is connected to the position of the preamplifier 7. At reproduction of a head 3, the switching means 16 of the 1st integrated circuit 5a is connected to the amplifier 15. At reproduction of a head 4, the reproduced output of the head 4 passes through a preamplifier 9 and a switching means 11 and then reproduced in the same reproducing route as the head 3 and a continous 4-channel reproducing output is obtained.
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