Resonant cavity methods of measuring ferrite properties

Formulae are given for the frequency shift on introducing a ferrite sample into a resonant cavity. Cylindrical rod, circular disk, and spherical samples are considered; the sample may be placed in a region of zero electric or magnetic field, enabling magnetic and dielectric properties to be separately determined. The merits and demerits of the various sample shapes are discussed, and it is concluded that a spherical sample is usually best; in particular, with such a sample, the dielectric constant and permeability can be measured on the same sample, in the same cavity, working in the same mode.