1. Patentansprak: 1:o) Eektriskt urladdningsror med flera elektroder, vilka, forenade till ett antal for alike 2— — andamal tjanande kombinationer, aro pa sadant sat anordnade pa hada langsidorna av en eacda indirekt upphettbar katod, aft pa ena sidan befinner sig en kombinaton ooh pa den andra siclan en annan kombination, kannetecknat darav, aft det i en air kombinationerna katoden narmast liggande gallret (2) samtidigt bildar ett i en annan kombination katoden joke narmast liggande galler. 2:o) Elektriskt urladdningsror enligt patent_ anspraket 1:o), kannetecknat darav, aft det i en elektrodkombination katoden narmast liggande gallret (2) bildar det i en annan elektrodkombination fran katoden raknat tredje gallret. Stockholm 1940. Kuugl. Boktr. P. A. Norstedt & Boner 4000891. Patent claims: 1: o) Electric discharge tubes with several electrodes, which, combined into a number of different combinations serving each other, are thus arranged on both long sides of an indirectly heatable cathode, one side being located on one side. a combination ton ooh on the other siclan another combination, can be drawn therefrom, aft it in an air combinations the cathode nearest grid (2) at the same time forms in another combination cathode joke nearest grid. 2: o) Electrical discharge tube according to patent claim 1: o), can be drawn therefrom, since the grid (2) closest to the cathode in an electrode combination forms the third grid in another electrode combination from the cathode. Stockholm 1940. Kuugl. Boktr. P. A. Norstedt & Boner 400089