GB428452A - Improvements in or relating to thermionic valves - Google Patents

Abstract

428,452. Thermionic valves. TELEFUNKEN GES. FUR DRAHTLOSE TELEGRAPHIE, 12, Hallesches Ufer, Berlin. Oct. 10, 1933, No. 27926. Convention date, Oct. 15, 1932. [Class 39 (i)] In a valve having a " regulating cathode " according to Specification 418,132, the source of electrons K is of the indirectheated type and the construction and arrangement of the grid electrodes are such that the effect of the field of the control grid G acting through the velocity regulating grid B on the density regulating grid D is 5 per cent or less, i.e. the grids acting as a triode have an amplification of at least 20. The field of the velocity regulating grid B acting through the density regulating grid D on the source of electrons K is not less than 10, i.e. those electrodes regarded as a triode have an amplification factor less than 10. The valve shown has also a screen grid SG, a suppressor grid TG, and a screening grid T arranged between the grids B, D so as to ensure independence of the functions of those grids. A filling of unspecified gas at a pressure of 10<-2> to 10<-4> mm. may be provided. Dimensions and voltages are given. The velocity regulating grid B may be arranged eccentrically with respect to the control grid G so that any reversal of electron movement about the " virtual cathode " surface is caused to occur asymmetrically and the formation of oscillations is prevented. The Specification as open to inspection under Sect. 91 comprises also (a) a valve in which the screening grid T is directly connected with the cathode ; and (b) a valve for use with magnetic fields in which the anode has annular slots. This subject-matter does not appear in the Specification as accepted.