ABSTRACT
Virtual cathode oscillators are experiencing something of a renaissance with new developments on the scene. Three variants in particular are notable-cavity vircators, tunable vircators, and the coaxial vircator. These may overcome two problems that have plagued devices of this type: low efficiency and sensitivity to gap closure in the high-current, explosive emission diodes. Nevertheless, despite their efficiency problems, these sources are attractive in applications requiring a simple source configuration-vircators many times employ no applied magnetic field and no SWS-and low device impedance, which permits high power operation at low voltage or optimizes coupling with low-impedance power sources such as explosive generators, which are a compact, energy-rich power source.
