| 摘要 |
<p>PURPOSE:To reproduce a control signal correctly even if a playback tape speed varies and the playback level varies by amplifying the reproduced control signal with the degree of amplification in inverse proportion to a tape traveling speed. CONSTITUTION:A capstan 301 is driven by a capstan motor 302 and a magnetic tape 300 is made to travel at a normal playback speed. A frequency generator 304 generates an AC signal corresponding to the rotating speed of the motor 302 and a frequency-voltage converting circuit 305 converts it into a voltage, which is supplied to an amplifying circuit 308. The circuit 308 amplifies the control signal, which is reproduced by a playback head 303, with the degree of amplification in inverse proportion to the supplied voltage. A waveform shaping circuit 307 compares the amplified control signal with a specific voltage level, shapes the waveform, and supplies the resulting signal to an output terminal 308.</p> |
