GB844849A - Improvements in or relating to electronic storage and switching arrangements - Google Patents

Abstract

844,849. Circuits employing bi-stable magnetic elements. NATIONAL RESEARCH DEVELOPMENT CORPORATION. March 13, 1957 [March 21, 1956], No. 8827/56. Class 40 (9). An arrangement comprising a magnetic storage core CA, Fig. 2, which provides a single output signal in response to two successive input signals and functions as a binary counter, has each input signal applied in the form of separate coincident current and voltage pulses to windings " 1 " and y respectively. The current input drives the core to the " one " remanent state, and if the core is initially in the " zero " remanent state a voltage is induced in winding y which disables a transistor gate TA in the voltage input circuit. A diode UA connected across coil y ensures that the voltage input is blocked by the gate for the duration of the input signal. The current input during the succeeding input signal is without effect as the core is already in state " one." No voltage is therefore induced in coil y, and the voltage input is effective over the transistor gate and a coil 2 X " 0 " to produce a current output, the latter coil having a sufficiently high m.m.f. to override coil " 1 " and drive the core back to the " zero " remanent state. The operative input signal also develops an output across a resistor RA, while voltage outputs are developed in a coil x without discrimination each time an input signal is applied. A number of the counters shown in Fig. 2 may be connected in cascade, in which case the cumulative effect of output pulse lengthening is minimized by the inclusion, at intervals, of the circuit shown in Fig. 3. In the latter arrangement a further core CB is used which is permanently biased in the " one " remanent state by a reset potential applied to a coil " I." The circuit output from CA is applied to CB by a 2X" 0 " overriding coil, and output voltage pulses of predetermined length are thereby obtained during the time periods when the core flux is changing. Specification 844,850 is referred to.