An electron gun that generates multiple electron bunches and the application of this gun to produce rf energy. The electron gun includes an rf input cavity having a first side with multiple emitting surfaces and a second side with multiple transmitting and emitting sections. The gun also includes a mechanism for producing a rotating and oscillating force which encompasses the multiple emitting surfaces and the multiple sections so electrons are directed between the multiple emitting surfaces and the multiple sections to contact the multiple emitting surfaces and generate additional electrons and to contact the multiple sections to generate additional electrons or escape the cavity through the multiple sections. A method for producing multiple electron bunches.