GB809849A - Improvements in signal synchronizer - Google Patents

Abstract

809,849. Magnetic recording and reproducing apparatus. SPERRY RAND CORPORATION. Nov. 5, 1956 [Nov. 16, 1955], No. 33724/56. Classes 40 (1) and 40 (2). In a magnetic tape record apparatus employing a plurality of longitudinal tracks for simultaneous reproduction, variation of synchronism between the tracks owing to skewing of the tape is compensated by deriving a difference signal from identical pulsed tracks at the outside edges of the tape, and utilizing said difference signal to apply time delays to the signal channels to correct the synchronization errors between said channels. Fig. 2 illustrates an embodiment of the invention in which numerals 18 to 23, inclusive, indicate a number of transducer heads in contact with a plurality of tracks on a tape 10. The outer heads 18, 23 carry identical pulse signals which are passed through inhibition gates G1, G3 and G2, G4, respectively, of a kind well known in the art, to flip-flop circuits FF-1 or FF-2, according to which input signal is leading, the output signal having a length corresponding to the time difference of the inputs. The signals from the flip-flops FF-1 or FF-2 are fed through rectifiers D1 or D2 to series resistances and capacitors R1, C1 or R2, C2 respectively, and the developed voltages applied to series-connected coils wound on magnetostrictive time delay elements in the circuits of the transducer heads 19 to 22, inclusive, carrying the signal channels. The number of turns on each of the time delay elements are progressively increased in opposite directions so that the greater time-delay required on the channels towards the edge of a skewing tape is proportionately applied.