A read head for a Wiegand wire has an E-core with a pick-up coil for the "1" bit wound on one outer leg and a separate pick-up coil for the "0" bit wound on a second outer leg. The E-core is composed of a relatively thin ferromagnetic E-laminae spaced from a relatively thick E- laminae. Between thin and thick laminae in each leg there is an appropriately polarized magnet. The result is to establish a first field across the face of the read head between the center leg and a first outer leg. This first field reads the one bits. Similarly, a second field between the center leg and the other outer leg reads the zero bits. Each one bit wire is on one side of the code strip and each zero bit wire is on the other side of the code strip so that the one bit and zero bit wires are passed respectively across the first and second reading fields provided by the read head. Saturation of the thin E-laminae and non- saturation of the thick E-laminae assures that the field configuration is appropriate to set and switch the Wiegand wires.
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