Steady-state, gas-filled orbitron maser

Summary Form only given, as follows. The gas-filled orbitron maser operates reliably in the steady state. The output consists of narrow lines that do not shift in frequency as the discharge current is varied. A typical spectrum of the microwave emission is shown. The line spectrum emitted suggests that an explanation of orbitron operation as two interpenetrating electron beams involved in a beam-plasma interaction is not applicable. It is believed that particle orbits produce the radiation, and not three-wave mixing. This is supported by observation of a large potential drop between the anode and plasma, indicating the presence of a large potential well.<>