| 摘要 |
PURPOSE:To reproduce a picture of excellent quality with neither the jitters nor color phase irregularity by giving a tracking correction function of obtaining a small wobbling value and broad control range. CONSTITUTION:At both ends of head bar 3 fitted to rotary shaft 2 of drum motor 1, piezoelectric elements 4a and 4b are arranged and to the both, rotary heads 5a and 5b are fitted. Once the output of oscillator 13 is applied to piezoelectric element driving amplifier circuit 18, elements 4a and 4b vibrate by deflecting at its frequency and heads 5a and 5b scan by vibrating in the width direction of a tape. This signal is supplied, field by field, to mixer 10, envelope-detected 11 and inputted to BPF12. The output of oscillator 13 and that of BPF12 are synchronously detected 14 and applied to integrator 15, where cumulative addition processes 16 and 17 are carried out to obtain a control voltage corresponding to a track shift value. This voltage is applied to circuit 18 together with the output of oscillator 13. Its output is separated by selector circuit 19 into two systems and supplied to elements 4a and 4b via a connection terminal by the signal of mixer 10. Consequently, control over the complete tracking of heads 5a and 5b are exercised. |
