GB1010405A - Apparatus for reproducing magnetically recorded television signals - Google Patents

Abstract

1,010,405. Editing magnetic tapes. FERNSEH G.m.b.H. July 16, 1964 [July 20, 1963], No. 29065/64. Heading G5R. Apparatus for reproducing video signals from a magnetic tape upon which they have been recorded in a series of tracks extending transversely across the tape comprises a rotatable carrier 21 provided with a number of heads 1 . . . 20 arranged, as said member rotates, to engage the tape at different positions relative to a fixed plane perpendicular to the axis of rotation of the carrier 21. The apparatus is used for editing, and the heads are arranged in a single turn helix around the circumference of the carrier 26, the axial distance between heads being such that with the tape stationary the successive heads scan successive transverse tracks to reproduce a repeated sequence of video signals corresponding to at least one picture frame. Instead of a single turn helix the heads may be arranged in a multi-turn helix, Figs. 9-13 (not shown). The heads, Fig. 5, are arranged in slots cut around the circumference of the carrier the axial spacing of the gaps 26 being by means of nineteen washers 39 having the same width as the gap, which are placed on either side of the head. Instead of a helical head arrangement, four coplanar heads 1 ... 4, Fig. 14, may be employed, and the carrier reciprocated axially by means of a rotating cam surface 64. This cam is driven via a clutch 71 so that with the clutch disengaged normal playback may be employed from a moving tape for monitoring. When the required frame is arrived at, the tape is stopped and the clutch engaged to give repeated scanning of the same frame. In operation, the tape is fed past a head carrier 103, Fig. 17, of one of the types previously referred to, and round a drum carrying two heads 81, 84 which are rotatable to scan the associated longitudinal sound and control tracks. A further drum 91 is also provided to store the signals on the loop being scanned when cutting. The length passage to be edited is selected by means of a contact 116 which engages with a rotating cardioid shaped element 115. By moving the contact further outwards, the engagement time between the contact 116 and element 115 is reduced. Cutting may then be effected by means of a knife blade, Fig. 18 (not shown). In a modification the temporary storage drum 91 is included within the main drum, Fig. 19 (not shown).