| 摘要 |
<p>PURPOSE:To drastically reduce the consuming quantity of a magnetic tape by operating a motor driving circuit and executing a recording onto the magnetic tape only when the output signal of a level detecting circuit is generated. CONSTITUTION:When a recording button is pushed in order to record an input signal generated from an input signal source 9 onto the magnetic tape, a first switch 13 is opened, and the input signal is amplified by a preamplifier 10, attenuated by a volume 11, amplifier by a main amplifier 14 and conducted out to an output terminal 15. At such a time, when the output signal level of the main amplifier 13 is lower than that of a reference voltage, an output signal from a first comparator circuit 16 is not generated, a second switch 21 maintains in an opened condition, a motor driving circuit 20 is not generated, a motor 19 is not rotated, and the magnetic tape is not made to travel. When the output signal at a level larger than that of the reference voltage is generated from the main amplifier 14, the output signal is generated from the first comparator circuit 16, the charging of a capacitor 17 is started, and the motor 19 starts the rotation by the output signal from the second comparator circuit 18.</p> |
