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The construction and the fundamental studies of a high-dose- rate stroboscopic x-ray generator utilizing a hot-cathode radiation tube for high-speed radiography are described. This generator consists of the following essential components: a constant high-voltage power supply, an energy-storage oil condenser of about 0.1 (mu) F, a grid pulser, a dc power supply for the filament, and an x-ray tube. The x-ray tube is a glass-enclosed hot-cathode triode and is composed of the following major parts: an anode rod made of copper, a tungsten plate target, an iron focusing electrode, a tungsten hot- cathode (filament), a tungsten grid, and a glass tube body. The electron beams from the cathode are accelerated by both the grid and anode electrodes and are roughly converged to the target by the focusing electrode. In the present work, the storage condenser is charged up to 70 kV by the power supply, and the electric charges in the condenser are discharged repetitively to the x-ray tube by the grid pulser. Because the cathode current is increased by increasing the positive grid voltage, high-dose-rate repetitive x-rays are then produced. In this generator, the cathode current which is almost equivalent to the tube current is primarily regulated by the filament temperature (fulminate voltage). The pulse widths of x-rays were about 600 ns, and the maximum repetition rate was about 50 kHz. The cathode current was less than 3.1 angstrom, and the x-ray intensity had a value of 35.2 nC/kg at 0.5 m per pulse with a charging voltage of 70 kV and a filament voltage of 12 V.
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