| 摘要 |
PURPOSE:To improve the S/N of the control signals of rotary heads and obtain good video signals by modulating sine waves by the driving signal and transmitting the same. CONSTITUTION:The reproduction signals from rotary heads 11a, 11b are outputted to terminal 35 via rotary transformer 21 and are also supplied to a tuning circuit 48, from which the horizontal synchronizing signal components are extracted and are sample held 49 by the horizontal synchronizing signal, whereby oblong frequencies are extracted 5 and are sychronously detected 52 by the output of an oscillator 36. The correction voltage is formed by an LPF 53 and is superposed 37 to the output of the oscillator 36. The output control voltage thereof is FM-modulated 39 and is converted to sine waves by a BPF 40, which are then FM-modulated 44 via rotary transformer 24 and the control voltages of sine waveform are applied via drive circuit 45 to the bimorph plates of head mounting devices 12a, 12b. |
