| 摘要 |
PURPOSE:To shorten a data processing time and to reduce a calculation error, by providing a specific operating means for switching in accordance with a tape running speed when reproducing, switching a carrier frequency of an FM wave in case of recording, and a reproducing FM wave in case of reproducing, and easily obtaining a conversion ratio of a simple number of 2<n> and 10 times. CONSTITUTION:A frequency modulating circuit 13 is provided with an operating means for switching the center frequency in response to switching of a tape running speed, and a motor controlling circuit 14 switches running of a tape to a multistage. An FM demodulator 25 contains a switch responding to operation of a standard speed changeover switch 15, and a switch responding to operation of a speed increase/decrease changeover switch 17, and is constituted so that a generation time point of a demodulation control signal can be switched so as to make a DC level of a reproducing analog output constant, even if speed of a tape is varied when reproducing. The switch 17 is operated only when reproducing, obtains speed of 25% increase and 20% decrease of a standard tape running speed, and is capable of setting a conversion ratio to integer times of 10. |
