Magnetic core device

981,855. Magnetic storage devices. AMP Inc. Nov. 12, 1963 [Nov. 23, 1962], No. 44561/63. Heading H1T. [Also in Division H3] An EXCLUSIVE OR device comprises a rectangular loop core 10 (Fig. 2), having input windings X1 and Y1 energizable to switch the remanent flux in different paths, an output aperture 41 through which passes an output winding Z1, a priming winding 61 passing through aperture 41 and capable of switching flux about that aperture after flux switching has been produced by one, but not both, of the input windings and a clearing winding 51 (which may be separate from the priming winding 61) which when energized reverses the direction of the flux in one of the limbs of the output aperture 41 so inducing a substantial output. The core begins in the cleared state with all the remanent flux clockwise (Fig. 3, not shown). A single input in either X or Y then produces flux in opposite directions on both sides of output aperture 41 (top arrangement in Fig. 3A or 3B, not shown), due to the action of the Figure eight winding 81, 91. A smaller rectangular priming pulse then switches flux at aperture 41 so that it is all anticlockwise in relation to that aperture (see lower part of Fig. 3A, not shown). A clearing pulse in winding 51 then reverses the direction of the flux in the outside leg at aperture 41 and a large output is produced. Simultaneous pulses in X and Y produce fluxes in the same direction on both sides of 41 and reversal of this on clearing produces equal and opposite voltages in loops 81 and 91 and hence no output. If the load is not of high impedance a rectifier may be connected in the output circuit or a second core 11 may be employed. An output as shown in Z1 then reverses the clockwise flux around the major aperture 21 of core 11 inside apertures 31 and 41, the flux round 41 is then reversed slowly by a small current in 13 and a clearing current IA in 12 then switches the flux in the outer leg of aperture 41 thus producing an output in 14 which may be connected to a further storage core. Cores 10 and 11 may be replaced by a single core with suitable flux paths.