A New Water-Cooled Power Vacuum Tube

Part I. The evolution of transmitting tubes is outlined. The ever present desirability of using a single tube for a given power output instead of paralleling several smaller tubes leads finally to the design and construction of tubes with 100-kw output, or larger. The design of a tube for 100- to 200-kw output is described. A basically new feature of the tube is a water-cooled grid, consisting of a column of fiat molybdenum disks. With such a structure, grid emission and dynatron effect are eliminated completely. The specific features in the manufacture of larger tubes are discussed. Part II. Curves are given showing the operation of the tubes as Class A, B, and C amplifiers.