| 摘要 |
PURPOSE:To erase a magnetic tape without using a full width erasing head by supplying an erasing current to a wide width head for a special reproducing use or an SP exclusive head, and erasing only an area of a corresponding portion of 40 deg. of a cylinder winding angle, in a mode for recording a PCM sound signal. CONSTITUTION:Switches 28, 29 are connected to a section contact (b) of about 40 deg., in which a PCM voice is recorded, and controlled by outputs (E), (F) of a logical circuit 32 so as to be connected to a section contact (a) of the remaining 180 deg.. An input D of this logical circuit 32 is a signal which becomes a 'High' level in the section of 40 deg. for recording the PCM voice and outputted from a PCM signal processing circuit 20, and an input B is almost the same signal as a head switching pulse (B) of 30Hz made from a tack pulse from a cylinder motor. In an overlap PCM mode, a switch 34 is turned on, an erasing signal from an oscillator 33 is amplified enough by an amplifier 35, and thereafter, an erasing current is supplied to a full width erasing head 42. |
