Abstract
A simple broadband ferromagnetic resonance spectrometer was assembled for observing magnetostatic modes in yttrium-iron-garnet films while sweeping frequency. The spectrum of a rectangular sample is studied close to a ground plane and far from it in the perpendicular configuration. The modes are identified and analyzed using the theories for infinite films. It is shown that modifications of the theory are needed due to the variations of the demagnetization field in the sample and due to propagation effects.