Patent GB-786042-A (GB)
Title: Apparatus for re-arranging digital-data sequences on a magnetic storage tape or the like
IPC: B41J3/50
Filed: 1950-06-23
Abstract: 786,042. Rearranging digital data. DIRKS, G. June 23, 1950 [Oct. 1, 1948], No. 37223/54. Divided out of 786,021. Class 106 (1). In an apparatus for sensing sets of signals recorded on a magnetic storage element in an original sequence and re-recording the sets of signals in a re-arranged predetermined sequence, the signals are sensed in sequence and repeatedly and switching means operating in synchronism with the sensing passes selected signals at each repetition to a recording means. In one embodiment signals in an original sequence are read from a magnetic tape 12 by a head 20 and fed to the parallelly-connected control grids of a series of pentodes 29<SP>-9</SP> to 29<SP>+9</SP>, each of which has in its anode circuit a recording magnet 14<SP>-9</SP> to 14<SP>+9</SP> for recording on a multi-channel tape 10. Also associated with each pentode 29<SP>-9</SP> to 29+9 is a gas tube 30<SP>-9</SP> to 30<SP>+9</SP> which, excepting when conducting, holds the screen grid of the pentode at a cut-off potential. The control grid of each gas tube 30<SP>-9</SP> to 30<SP>+9</SP> is connected to one of the rows of a plug board 5 which is set up in accordance with the re-arranged sequence required, but only so far as movements of not more than 9 positions (positively or negatively) are concerned (see Figs. 1 to 3, not shown). A second plugboard 4 whose rows are made operative one at a time by a step-by-step switch 36 ensures that re-arrangements involving a shift of 10 to 19 positions are dealt with during a second stage, those involving a shift of 20 to 29 positions during a third stage, and so on. The circular scanning of the beam of a cathode-ray tube distributer 16 is developed from a synchronizing signal picked up from the tape 12 by a head 21. As the beam passes over target elements 17 successive columns of the two plugboards 4 and 5 become operative. When a plug connection completes a circuit through the plugboard 4 and stepping switch 36, a gas tube 28 is ignited and supplies H.T. to all the pentodes 29<SP>-9</SP> to 29<SP>+9</SP>. At the same time a plug connection in plugboard 5 completes a circuit to fire one of the gas tubes 30<SP>-9</SP> to 30<SP>+9</SP> and this raises the screen grid potential of its associated pentode, allowing the latter to amplify and the associated head 14<SP>-9</SP> to 14<SP>+9</SP> to record on the tape 10, the signal or signals detected by the sensing head 20 at that moment. The signals thus distributed in a two-dimensional fashion are indicated in one example, Fig. 4, by numbers representing their destined positions in the re-arranged sequence. Final transfer in this sequence from tape 10 to tape 13 is performed by a row of sensing heads 8<SP>+9</SP> to 8<SP>-9</SP>, arranged in staggered fashion and connected in parallel to drive, via a pentode 44, the final recording head 24. Before a second cycle of the C.R.T. distributer commences the stepping switch 36 steps to the second row of the plugboard 4 to deal with thos items which must be shifted by more than 9 steps during a second sensing of the original arrangement on the tape 12. Alternatively, the rows of plugboard 4 could be connected to control recording heads spaced over the secondary tape 10 at distances ten units apart and the tape 12 would then require only one sensing. Moreover, elements 14<SP>-9</SP> to 14<SP>+9</SP>, 29<SP>-9</SP> to 29<SP>+9</SP>, 30<SP>-9</SP> to 30<SP>+9</SP>, &c., could be reduced in number by restricting shifts to the positive direction only. Instead of the three separate tapes, a single tape could be used. Specifications 786,025 and 786,041 also are referred to.