| 摘要 |
PURPOSE:To eliminate the need for an electronic switch which connects and disconnects a resistance for dubbing and a bias power source for dubbing by connecting the series circuit of a resistance and a capacitor between the input terminal and output terminal of a recording amplifier circuit, and feeding back the output of the recording amplifier circuit negatively. CONSTITUTION:When the output terminal 22 of the recording amplifier circuit 11 and the input terminal 23 of a regenerative amplifier circuit 12 are connected to a rotary head 34 through a rotary transformer 33 without the intervention of a changeover switch, dubbing is performed so that a recording current does not resonate owing to the inductance and stray capacity of a rotary head 34 during recording and a reproduced signal has no deterioration in S/N ratio during reproduction. For this purpose, the series circuit of the resistance RF and capacitor CF is connected between the output terminal 22 and input terminal 21 of the recording amplifier circuit 11 and negative feedback from the output terminal 22 of the recording amplifier 11 to the input terminal 21 is provided. |
