Traveling wave tube comprising periodic permanent magnetic focusing system with glass/epoxy retaining means

摘要

A traveling wave tube has a cylindrical vacuum envelope surrounding a delay line. The vacuum envelope is tightly surrounded by a permanent magnet system of ring-shaped pole discs and of magnetic rings respectively arranged between the pole discs and oppositely polarized in alternating fashion in an axial direction. The permanent magnet system is inserted into an outer envelope in form-fit fashion. An attitude and position retention for the focusing elements which is resistant to temperature shock is provided in the traveling wave tube. For this purpose the permanent magnet system is glued at its outside generated surface and the glue is formed of a mixture of an epoxy resin having adhesive properties and of glass fibers provided therein in an undirected attitude. This traveling wave tube is useful given extreme temperature fluctuations, such as in a range from -60 DEG C. through +95 DEG C.