Characteristics of a high-power RF oscillator based on a pulsed hollow-cathode discharge

The characteristics of a very simple high-power pulsed RF oscillator are presented. This oscillator is based on the use of a low-pressure pulsed hollow-cathode discharge during the periods when its cathode sheath becomes unstable. A set of four different oscillators has been studied in different operating regimes for various values of load resistance. These oscillators were tested and found to produce pulsed power of over 100 kW with efficiency exceeding 20% at frequencies up to 50 MHz. The tests were performed with pulse duration of 14 μs and repetition rate up to 100 Hz. Equivalent circuits of the oscillator for RF loading and for DC current are described. The requirements for a power supply to drive the device as well as recommendations for the oscillator usage are presented