Rotating head type magnetic record/reproduce apparatus

Claim 1

A helical-scan type rotating head PCM record/ reproduce apparatus comprising: (a) PCM recording signal processing means (100) having a converter (2) for converting an analog input signal to a digital signal, and digital signal processing means (3) for adding an error detecting/correcting signal to said digital signal; (b) record/reproduce means for recording an output signal from said PCM recording signal processing means (100) on a magnetic tape (8) in an oblique direction and reproducing said recorded output signal, said means having first and second record heads (33, 35) and first and second reproduce heads (34, 36) alternately disposed in the rotating direction; (c) PCM reproducing signal processing means (200) having a digital-signal processing circuit (13) for performing error detection/correction process to the signal from said reproduce head (34, 36), and a D/A converter (14) for converting said processed signal to the original signal; said first record and reproduce heads and second record and reproduce heads of said record/ reproduce means being disposed with a spacing of not more than 90°, and said record heads being displaced by a predetermined track width from said reproduce heads in the track width direction so that the same track is traced by said record and reproduce heads; (d) storage devices (25, 30) coupled to said digital-signal processing circuits (3, 13) of said PCM recording signal and reproducing signal processing means so as to write the digital signals from said processing circuits and to read at different time from said writing time; (e) record/reproduce change-over switch circuits (26, 29) provided on the lines for a signal to be recorded and for a reproduced signal of said PCM recording signal and reproducing signal processing means (100, 200) so as to turn on and off said signals, respectively; and (f) control means (31) coupled to said digital signal processing circuits (3, 13) and said switch circuits (26, 29) of said PCM recording signal and reproducing signal processing means (100, 200) so as to compress, expand and on-off control the digital signals, said control means including a timebase-conversion control section (31a) coupled to said digital-signal processing circuits (3, 13) of said PCM recording signal and reproducing signal processing means (100, 200) so as to compress the timebases of the digital signals in said digital-signal processing circuits to within a head-rotation angle of 90°, and expand the timebases of said timebase compressed signals to a head-rotation angle of 180°, and a record/ reproduce switching control section (31b) coupled to said switch circuits (26, 29) of said PCM recording signal and reproducing signal processing means (100, 200) so as to alternately turn on and off said switch circuits in association with said timebase compression and expansion time, whereby said digital signal is recorded and reproduced alternately and intermittently.