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A compact PFN (pulse forming network)-Marx generator, which is based on mica capacitors, is constructed to generate intense electron beams for the purpose of high-power microwave generation. The key components of the generator, including a PFN-Marx, a trigger source, a multi-stage gas switch, and a load, are introduced in this paper. The PFN-Marx is composed of 19 PFN modules, which are formed by four mica capacitors in parallel. The temperature characteristics and pulse characteristics are tested in this study. The mica capacitor is insensitive to the temperature, and its lifetime is tens of thousands. Considering the influence of the ultraviolet light pre-ionization, gas gap switches are assembled in a nylon house. The trigger source, which is a mini-Marx generator based on the integration into the magnetic transformer and the magnetic switch, is used for increasing the stability of the switches. The generator has been tested on a water load and a relative magnetron. The experimental results show that this generator can deliver electrical pulses with the pulse width of 120 ns and the amplitude of 400 kV on a 40-Ω water load at a repetition rate of 50 Hz. In addition, utilizing the generator to drive a Ku band magnetron at a voltage level of 330 kV, a 500 MW microwave pulse with the pulse width of 50 ns at the frequency of 14.4 GHz is obtained.

A vertical glass tube (1 cm bore and about 100 cm long) carries at its closed upper end two opposed spherical platinum electrodes, approximately 1 and 2 mm in diameter. The lower end of the tube is bent upward in the form of a J, to which is attached a cylindrical reservoir. After introducing sufficient electrolyte (1NH2SO4) to more than fill the long tube, the system is evacuated and sealed off.On rotating the long tube from an inverted to a vertical position, the column of liquid remains hanging from the top of the tube, under a negative pressure (at the top), equal to the length of the column down to the meniscus, times its density, less the vapor pressure in the reservoir. The minimum electric charge required to drop the column is determined by successive trials, using a mica capacitor (adjustable in steps of 0.001 μf), which is first charged to a known potential and then connected to the electrodes through a quick‐acting switch. After each drop of the column, the polarity is reversed. Hydrogen is dep...