| 摘要 |
PURPOSE:To eliminate the need for a switch circuit which has high dielectric strength by enabling a simple switch circuit to achieve switching between recording and reproduction, by providing an impedance element, the switch circuit, etc., at specific positions. CONSTITUTION:When a recording and reproduction changeover switch 5 is placed at a contact P for reproduction, a regenerative amplifier 3 is powered up and a transistor (TR) 19 turns off, so that a playback signal detected by a recording and reproducing head 1 appears at an output terminal 8 through the regenerative amplifier 3. For recording, the switch is connected to a recording-side contact R and while a recording amplifier 2 and a recording bias circuit 4 are both powered up, the TR19 turns on. Then, a signal applied to a recording input terminal 9 is applied to the head 1, together with a bias signal, through a parallel circuit of a capacitor 11 and a resistance 10. For those cases, a resistance 20 is provided in order to prevent a high recording bias from being applied to the TR19 and regenerative amplifier 3. |
