Electron tubes at millimeter and submillimeter wavelengths

New results concerning a two watts c. w. two millimeter Carcinotron are shown, to be used as a basis for an evaluation of further possibilities in the generation of higher powers at higher frequencies. It is the feeling of the authors that the ultimate performances of the conventional devices have been somewhat underestimated in the past and that useful operation can be obtained in the submillimeter region. To demonstrate this point they discuss the feasibility of tubes in the 0.5 mm- 0.3 mm region. They give laboratory results obtained with tubes operated well below 1 mm.