The Variation in the High-Frequency Resistance and Permeability of Ferromagnetic Materials due to a Superimposed Magnetic Field

The variation of the high-frequency resistance of ferromagnetic conductors as a function of a superimposed magnetic field is discussed. It is shown that very large changes in high-frequency resistance are obtainable in ferromagnetic conductors having high initial permeabilities. Some important applications of this effect are given. The application of high-frequency incremental permeability to remote tuning of radio circuits is briefly outlined.