Flux linkage between two solenoidal tape windings as a factor in the reading of cylindrical thin-film logical elements

Cylindrical ferromagnetic films can be used as logical elements, and when axially aligned they are energized, and the remanence is sensed, by cylindrical current sheets. The read `1¿ to `0¿ ratio is influenced by the mutual inductance between the sheets. The mutual inductance between two solenoidal tape windings has been measured, the windings being formed around a copper rod because the films are mostly produced by electrodeposition on to a conducting substrate. The experimental results have been compared with the solutions of the magnetic-field diffusion equation, thereby establishing the relative importance of the dimensions and resistivities of the various conductors in the frequency range 0 to about 10 Mc/s.