198390 ⎘
Driving, starting or stopping record carriers of filamentary or web form; Driving both such record carriers and heads; Guiding such record carriers or containers therefor; Control thereof; Control of operating function; Control of operating function, e.g. switching from recording to reproducing; Masking of heads; Selecting or switching of heads between operative and inoperative functions ; Masking of beams, e.g. of light beams Masking or switching periodically, e.g. of rotating heads