| 摘要 |
PURPOSE:To reduce the number of parts by sharing one amplifier out of plural differential output circuits in each channel. CONSTITUTION:A recording signal is inputted from an input terminal 8, an A-channel (Ach) signal is inputted to an Ach amplifier 5 by an A/B change-over 7 to driven by a switching signal for an Ach head 1 and a Bch head 2 and a Bch signal is inputted to a Bch amplifier 6. When the Ach/Bch switching signal is high, only the Ach amplifier 5 is driven and the Bch amplifier 6 is actuated. When said switching signal is low, only the Bch amplifier 6 is driven and the Ach amplifier 5 is not actuated. An output amplifier 12 is driven independently of the switching signal an always outputs a signal having a phase different from that of the input signal by 180 deg.. When the Ach/Bch switching signal is high, differential output operation is applied to the Ach head 1 by the combination of the Ach amplifier 5 and the amplifier 12, and when the switching signal is low, differential output operation is applied to the Bch head 2 by the combination of the Bch amplifier 6 and the amplifier 12. |
