High performance vacuum electron tube - comprising cathode with cathode wire in evacuated inner space of housing

摘要

High performance vacuum electron tube comprises a cathode (3) with at least one electron-emitting cathode wire (4) arranged in an evacuated inner space (2) of a housing (1). The novelty is that the wire (4) comprises a wire rod (5) having a porous jacket (6) around it. An additional material is inserted into the porous jacket and is distinguished by a high electron emission at low temps.. The cathode (3) is a rod cathode comprising a number of cathode wires (4) running parallel to each other. The wire rod (5) is made of a high temp. resistant metal, pref. W. The porous jacket (6) is made of sintered W-powder and completely surrounds the rod (5). The additional material is BaO. The porosity of the jacket (6) is pref. 30% and the wires (4) have a dia. of pref. 1mm. ADVANTAGE - The tube has a long service life.