GB1372973A - Video tape recorder system having means for suppressing video track crossover noise during slow and fast motion operation - Google Patents

Abstract

1372973 Video recording and playback VIDEO LOGIC CORP 10 Feb 1972 6385/72 Heading G5R In a video system where more than one field is recorded in each track, e.g. as in Fig. 4 where vertical sync. regions 37/37<SP>1</SP> sandwich two intermediate fields in each track 34, means is provided to blank out reproduced fields containing noise picked up when a scanning head crosses a guard region 35 between two tracks, e.g. when the tape is moved at a different speed from that when the tracks were recorded. In the pulse control circuitry shown, a master flip-flop 84 (Fig. 5A) is always energized to control a gate 93 (Fig. 5D) such that a brightness control circuit is turned down during reproduction of one of the two fields in each track; should the crossing of the scanning head 31 into a guard region 35 occur during such a blanked off field, no further action is taken by the circuitry. When however the crossing changes to the reproduction time of the non- blanked field, a noise pulse from an amplifier (112, Fig. 5C, not shown) is used to switch the flip-flop 84 so that all formerly blanked fields are now reproduced, and all reproduced fields now blanked. In a twohead arrangement (Fig. 8, not shown), blanked fields from one head are filled with reproduced fields from the other. (For Figures see next page.)