| 摘要 |
PURPOSE:To perform high-speed mode switching and to obtain a sufficient recording output even with a low-level power source by using a class ''A'' amplifier circuit which uses a PNP transistor (TR) as a recording amplifier curcuit. CONSTITUTION:The class ''A'' amplifier circuit is composed of the 1st PNP type TR, and the recording amplifier circuit is so constituted that a recording signal to the class ''A'' recording circuit, whose collector output is inputted to one terminal of a stator-side coil R1. The 3rd TRQ3 turns off during reproduction to lead out a reproduced signal which is stepped up by about twice. A capacitor C is charged on mode switching from reproduction to recording and discharged on the opposite mode switching, and the delay of the circuit due to the charging and discharging is extremely short, so that the mode switching is speeded up. |
