| 摘要 |
PURPOSE:To obtain a high speed reproduction control circuit while noise bar is fixed completely by using an ouput of phase comparison corresponding to a head switching pulse frequency at high speed reproduction so as to control the phase of a capstan motor. CONSTITUTION:A CTL pulse from a control head 6 is frequency-divided by a frequency division circuit 19 at high speed reproduction and the frequency is switched into a frequency at recording. On the other hand, a changeover switch 16 is thrown to the position of a contact (b) and a head switching pulse HSW based on a PG pulse from a PG coil 17 is led out of the contact (c). The HSW is delayed by a delay circuit 2, the delayed signal is fed to a phase comparator 5, where the result is compared for the phase with the CTL pulse subject to frequency division. The output of phase comparison is fed to a capstan motor drive circuit 9 as a phase control signal so as to attain the phase contol of the capstan motor 10. The position of the noise bar is changed freely by varying the delay time of the HSW and a stable picture is obtained.
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