GB688567A - Improvements in or relating to magnetic recording and reproducing - Google Patents

Abstract

688,567. Statistical apparatus; recording apparatus. STANDARD TELEPHONES & CABLES, Ltd. Oct. 6, 1950, No. 24449/50. Classes 106 (i) and 106 (iv). A method of recording and reproducing intelligence on an elongated magnetic recording medium in the form of an endless band, comprises the steps of producing in a part of the medium a signal which can be distinguished by means including reproducing apparatus from a record of intelligence, recording on a following part of the medium a batch of intelligence, running the medium through reproducing apparatus till the signal is recognized by the distinguishing means and then reproducing the batch of intelligence. Specification 685,032, [Group XL (b)], is referred to. In the described embodiment an endless band of magnetic tape is contained in a narrow box 5 and arranged to pass through a recording head 1 with associated driving rollers 2, and a reproducing head 3 with independent driving-rollers 4. A tight-tape device 7 controls the tape drive when the tape is pulled tight between the two heads. A first operator records certain information (e.g. data for entry into a digital electronic calculator) on the tape and this is later played back and checked against an entry by a second operator and the checked or corrected version re-recorded. The portion of the tape shown with black dots represents the first recording which has now passed through the reproducing head 3, the zig-zagged section 16 represents a part of the tape on which a distinguishing signal, referred to above, is recorded, or this portion may be left " clean." The tape marked with small open circles represents the portion on which the checked data has been re-recorded by the head 1; a " clean " part is' left behind the checked data to allow the latter to be completely reproduced by the head 3 before the tight-tape device 7 stops the tape. If the checked data is to be played back a second time the tape drive 4 is reversed until the head 3 recognizes the part 16 of the tape when the drive is automatically reversed again and the checked data reproduced once more. There may be a plurality of checked messages recorded on a single tape.