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An investigation was conducted to determine the feasibility of a novel crossed-field amplifier which employs secondary emission from portions of the slow-wave circuit. This circuit is located in the position normally occupied by the sole electrode in a conventional crossed-field amplifier. Power is transferred from the beam to the circuit by virtue of the negative resistance developed when more electrons leave an electrode than are incident at a time when the polarity of the rf voltage on this electrode is positive with respect to the preceding electrode of the circuit. (Author)

The purpose of this study is to develop a novel, injected-beam non-re-entrant crossed-field amplifier employing a cycloiding electron beam. Fast bunching of the cycloiding beam occurs since the unfavorably phased electrons are collected on the sole as interaction with the RF field begins. The activity of the third quarter centered around constructing and testing a demountable amplifier, including the measurement of the cold loss of the interdigital circuit and the input-output match. Various incidental difficulties prevented operation of the amplifier. A cold loss of about 6.5 DB was measured for a line with molybdenum vanes and copper back wall. The RF window has a VSWR < or = 1.2 and the coaxial-to-interdigital line transition has a VSWR < or = 1.6. It was concluded that all copper slow-wave structures with greater back-wall spacing would be required in order to minimize the loss. (Author)