The magnetron as a negative-resistance amplifier

A one-port, nonlinear, crossed-field microwave amplifier which uses a magnetron as a negative-resistance element is described. Such an amplifier is characterized as one using an emitting sole, reentrant beam, and reentrant RF fields. A circulator is required to achieve stable regenerative amplification. The system is analyzed as a negative-resistance amplifier and as a synchronized or forced oscillator. Experimental measurements of gain and bandwidth are illustrated. The effect of varying operating conditions upon these characteristics is indicated. Operation with a solid cathode composed of oxidized beryllium-nickel has been demonstrated.