Development of an advanced electron gun for high power radar applications

Existing klystron high power amplifiers used for wide-band, S-band radar incorporate a gridded electron gun developed prior to the 1960s, which uses an oxide cathode. Since then, the electron gun technology has evolved including many new materials and advanced manufacturing techniques. Thus, the cost to manufacture these older guns can be improved to reduce the financial burden to the end user. This development program addresses the high costs and low reliability with the existing design by replacing the oxide cathode with a dispenser. A dispenser cathode can survive high power arcs without significant damage or degradation of performance. Recovery time is reduced since it is directly related to arc damage. More importantly, a dispenser cathode can be reused when exposed to air during repair, thereby reducing the overall repair costs. The principal goal of the program is to develop a replacement electron gun utilizing the latest advances in materials, manufacturing and assembly techniques. Since the new gun is designed to be a replacement of the existing gun, it is important that the new design provides the same beam optics performance.