The reflex klystron as a negative resistance type amplifier

A reflex klystron has been tested as a narrow-band amplifier at 11,000 mc. The performance is predicted rather accurately from simple theory and steady gain can now be obtained in the 30-db region with a bandwidth of the order of megacycles. A noise figure of 40 db was measured and the saturation power output was the same as the output of an oscillator. A circulator was used in these tests to separate input from output and we consider it important to use this component with any type of negative resistance type amplifier.