Abstract
The application of fast-passage techniques to NMR in ferromagnets is examined in some detail. It is shown that while this technique gives the distribution of hyperfine fields for ferromagnets with isotropic hyperfine fields, for anisotropic hyperfine fields the spectra are distorted by the enhancement factor. Co metal and nearest neighbors to impurities in Fe metal are discussed as examples. It is pointed out that large values of γH1 will also distort the spectra.