| 摘要 |
PURPOSE:To make tracking coincident between recording and reproduction by positioning a rotary head so that a vertical synchronizing signal is reproduced at positions synchronizing with the timing of the reproduction of control pulses. CONSTITUTION:A frequency-modulated signal reproduced from a magnetic tape 2 is passed through a rotary transformer and a changover switch 11, demodulated by a reproduced signal processing circuit 12, and led out as a reproduced video signal from a reproduced video output terminal 17. A control signal is led out of a control signal amplifier circuit 9 at its reproduced control signal test point 19 and supplied to the input terminal 21 of a channel 1 of an oscilloscope 20. Further, a video output signal from a video output terminal 17 is supplied to the input terminal 22 of a channel 2 of the oscilloscope 20. The semifixed resistance 25 of a self-recording and self-reproducing preset adjusting circuit 8 is so adjusted that the observed waveform 23 of the signal part of the reproduced video signal is in phase with a reproduced control signal waveform 24. Consequently, the tracking adjustment of self-recording and self-reproduction is made.
|
