Gating circuits employing magnetic amplifiers

841,492. Controlled non-linear inductors. SPERRY RAND CORPORATION. July 25, 1957, No. 23569/57. Class 40 (9). [Also in Group XIX] A plurality of resetting-type magnetic amplifiers are connected in parallel with a load. Several arrangements are described, all of which utilize magnetic cores of material having rectangular hysteresis characteristics such as Orthonik or Moly-permalloy, each core comprising a power and a control winding which are pulsed in different time positions by respective power and signal pulses. A core is normally saturated by the power pulses PP, but if a signal pulse SS is applied in the interval between two power pulses the core flux is temporarily reversed. During the power pulse period when the core is resaturated, the power winding has a high impedance. A coincidence gate is described, Fig. 4, which produces an output pulse in a load only when all the control windings are energized simultaneously. As shown, the load 28 is shunted by three parallel circuits each comprising a power winding 32-34 of a core 29-31. In the absence of a signal pulse to one or more of the control windings 39, the associated power winding is of low impedance and the load is short-circuited. Only when the signal pulses from sources SS-1 to SS-3 are applied simultaneously do all the power windings achieve a high impedance so that a PP pulse from the power source 16 passes to the load. Positive restoration of the core fluxes to their initial saturation state following the reception of control signals is effected by setting windings 41 which are energized from source 40 during the operative periods of the PP pulses. The coincidence gate may alternatively provide an output only when the signals are simultaneously absent. This gate is illustrated in Fig. 5 in which the signal sources are switches SS-1 to SS-3 in the circuit of a pulse source PP-2 operative alternately with PP-1, and the cores are biased by potentials 52, 54, 56 connected to the control windings 39. The gate is otherwise the same as that shown in Fig. 4. In operation the flux in each core is automatically reversed by the bias each time a power pulse PP-1 terminates, and the associated power winding present a high impedance to the next power pulse which then passes to the load. If, however, one or more of the switches are closed, the associated bias is neutralized by the PP-2 pulses and the core flux is unchanged. The power winding then short-circuits the load. In this arrangement the setting windi