GB1038599A - Circuit for editing tape recordings - Google Patents

Abstract

1,038,599. Editing records. MAGYAR RADIO ES. TELEVIZIO. Dec. 10, 1964 [Dec. 13, 1963], No. 50263/64. Heading G5R. When correcting mistakes made in the original sound record on a tape recorder 1 synchronized with a film projector 4, bias current is supplied to the record head after current is supplied to the erase head, the delay in unit 3 being equal to the travel time of the tape between the two heads, and both currents pass through a unit 2 which reduces the rate of rise of current and thereby prevents transients producing noise on the tape. The sound mixing amplifier 5 receives inputs from the synchronized tape recorders 7-9 and two non-synchronized tape recorders 10 and 11. When using only the synchronized recorders, all units are returned to a position before the mistake occurred and restarted with the record head short-circuited over a lead a. At the desired point the switch K is closed to energize the erase head, remove the shortcircuit from the record head, and, after the required delay, supply bias to the second head. When the non-synchronous recorders are used a second recording must be made of the whole scene. In a newsreel, for example, separate scenes may be prefaced by cue signals in the projector and by the sound of a gong 6, and when re-recording the cue signal may actuate the gong 6 and the switch K.