| 摘要 |
PURPOSE:To simplify the constitution of pickup part, to play back the video signal with high quality, and to ensure to detect the tracking error signal, by making the pickup of signal from two electrodes in time sharing mode. CONSTITUTION:Electrodes 2a, 2b have static capacity with the conductive layer forming the recording track 1, and this static capacity forms a part of resonators 3a, 3b. Thus, when a high-frequency exciting voltage from the oscillator 5 is fed to each resonator 3 via a switching circuit 6, AM modulation in response to the recording signal of track 1 is made, amplitude variance is picked up at envelope detectors 4a, 4b and recorded FM modulation signal is obtained. This signal is amplified 8 and TV signal is fed to the terminal 12, and a signal in proportion to the amplitude is detected at an envelope detector 9 and fed to the synchronizing detector 10, to obtain tracking error signal at the terminal 11. |
