A New Ultra-High-Frequency-Tetrode and Its Use in a 1-Kilowatt Television Sound Transmitter

A new tetrode suitable for use in the final stage of a 1-kilowatt ultra-high-frequency sound transmitter is described. Two of these tubes operated under plate-modulated conditions in such a transmitter will deliver 1 kilowatt of carrier output at 108 megacycles. Among the novel features of the design are the use of a metal header to provide a low-impedance screen-grid connection, beam-forming grids, and a forced-air-cooled anode. The new RCA type S-1 transmitter which uses these tubes is described and its performance reported.