| 摘要 |
<p>PURPOSE:To use a coupling capacitor with small capacity, enable digitization, and reduce the size of a circuit by supplying the 1st signal and the 2nd signal which has a different waveform to a head alternately during the period of a program search within a specific period from the start of recording. CONSTITUTION:A control signal which is at a level H for about one second from the start of recording and then at a level L arrives at a terminal 28, and this control signal is supplied to an AND circuit 27, and also inverted by an inverter 29 and supplied to an AND circuit 20. Therefore, the signal from the AND circuit 27 is outputted through an OR circuit 33 for about one second after the start of recording, and then the pulse signal (erase signal) (e) from the AND circuit 20 is outputted through the OR circuit 33. The output signal of the OR circuit 33 is supplied to and amplified by an amplifier 30 with characteristics for removing higher harmonic components of the pulse signal (e) so as to prevent higher harmonic components from exerting influence upon a video signal to be recorded on a magnetic tape 32, and the amplified signal is supplied to the full-erasing head 31 through the coupling capacitor C2.</p> |
