  We demonstrate that the bandwidth of pulsed electrically detected magnetic
resonance can be increased to at least 80 MHz using a radio
frequency-reflectometry detection scheme. Using this technique, we measure
coherent spin oscillations in real time during a resonant microwave pulse. We
find that the observed signal is in quantitative agreement with simulations
based on rate equations modeling the recombination dynamics of the spin system
under study. The increased bandwidth opens the way to electrically study faster
spin-dependent recombination processes, e.g., in direct semiconductors which so
far have almost exclusively been studied by optically detected magnetic
resonance.
