Descriptors | Electron tubes, Electron tube structure, Electron tube components, Ceramics, Electronic equipment and components, Solid electrical insulating materials, Electrical insulating materials, Testing conditions, Permittivity, Dissipation factor, Electrical resistivity, Strength of materials, Thermal conductivity, Type testing, Specimen preparation, Mechanical testing, Breaking load, Test specimens, Dimensions, Deformation, Thermal testing, Visual inspection (testing), Acid-resistance tests, Pressure testing, Test equipment, Vacuum tubes, Microwave tubes |