DC, small, and large signal results are shown under continuous wave and pulsed conditions for a β-Ga 2 O 3 metal-oxide-semiconductor field-effect transistor operating at 1 and 2 GHz. The device has a maximum transducer gain, maximum output power, and peak power added efficiency of 13 dB (15 dB), 715 mW/mm (487 mW/mm), and 23.4% (21.2%), respectively at 1 GHz (2 GHz). We observe the continuous wave output power is limited to 213 mW/mm by drain dispersion likely from surface or interface traps in the gatedrain region as indicated by pulsed IV measurements. High parasitic resistances, as indicated by high knee voltages, also limit the power performance under continuous and pulsed large signal conditions.