| 摘要 |
<p>1,101,512. Disc recording. DECCA Ltd. 2 March, 1966 [26 March, 1965], No. 13005/65. Heading G5R. A bevelled recording stylus is heated so that its temperature and the corresponding softening of the disc material vary in accordance with the amplitude of the signal to be recorded. As shown, the signal is picked up from a tape 10 by a head 14. The same head or an advance head 41 feeds the amplified and rectified signal, together with a constant D.C. signal from a source 44, through an adder 45 to a stylusheating coil 40 (Fig. 3) and also to control a valve 48 which passes carbon dioxide or other extinguishing gas into a swarf-removal duct (Fig. 5). The heater current may alternatively be amplitude-modulated A.C. A modified system for stereo recording is described (Fig. 6).</p> |
