  Employing a broadband microwave reflection configuration, we have measured
the complex surface impedance, $Z_S(\omega,T,H)$, of single crystal
La$_{0.8}$Sr$_{0.2}$MnO$_3$, as a function of frequency (0.045-45 GHz),
temperature (250-325 K), and magnetic field (0-1.9 kOe). The microwave surface
impedance depends not only on the resistivity of the material, but also on the
magnetic permeability, $\hat\mu(\omega,T,H)$, which gives rise to ferromagnetic
resonance (FMR) and ferromagnetic anti-resonance (FMAR). The broadband nature
of this experiment allows us to follow the FMR to low frequency and to deduce
the behavior of both the local internal fields and the local magnetization in
the sample.
