A 20 KW-CW-X-band amplifier

This paper describes the performance of a 4-cavity klystron amplifier designed to deliver a power output of 20 KW, CW, reliably at a frequency of 8.35 Kmc. The tube operates synchronously tuned with a gain of 54 db and an efficiency of 31 percent. With the tube adjusted for 43 db gain, the efficiency is 38 percent. The tube is tunable over a frequency range of ± 50 mcs/sec. In the laboratory, the tube has delivered power outputs ot greater than 27.9 KW. The tube weighs approximately 7 pounds. The focusing electromagnet used for this tube weighs approximately 180 pounds. The important factors considered in the design of the resonant cavities, magnet circuit, and cooling of the tube will be discussed. Photographs of the tube and the experimental test set will be presented as well as performance data.