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Existing theories of the static magnetron do not predict violation of the Hull cut‐off condition or cathode bombardment. Measurements made at anode voltages and magnetic fields much larger than those used by earlier investigators revealed violations of the Hull cut‐off condition considerably more pronounced than those previously reported, and much greater amounts of cathode bombardment. When sufficient cathode bombardment takes place, emission may be enhanced (through secondary emission) by a factor of ∼103 over the thermionic value. When enhanced emission occurs in magnetrons employing pure metal cathodes, it is found that maximum current limits exist for each magnetic field. These limits form a maximum current boundary on a voltage‐current plot. The maximum current boundary depends on secondary emission properties of the cathode surface and on geometry. Experimental observations on enhanced emission, cathode bombardment, the maximum current boundary, and flow of anode current in violation of the Hull cut‐off condition are combined into a self‐consistent picture in static magnetrons employing pure metal cathodes. Although cathode bombardment and flow of anode current are still unexplained, their existence can account for the observed enhanced emission and maximum current boundary. In this it is unnecessary to endow the cathodes with anomalous thermionic or secondary emission properties. The process causing cathode bombardment, enhanced emission, and flow of anode current in violation of the Hull cut‐off condition is believed to be an electronic interaction which occurs almost entirely in the relatively dense region of space charge surrounding the cathode. The significant factors influencing the interaction appear to be applied electric and magnetic fields, space charge density, and thickness of the space charge sheath. The basic problem of electronic interaction in the static magnetron is partially - defined. It is expected that when a realistic solution to this problem exists, including a correct account of cathode bombardment, the occurrence of enhanced emission would be automatically predicted.