Envelope Supports Or Forms Electrode Patents (Class 313/244)
- At spaced or opposed portions of envelope (Class 313/253)
- Insulating or ceramic support rod or tube (Class 313/256)
- With spacer between electrode or electrode supports (Class 313/257)
- With indirectly heated cathode (Class 313/263)
- With U-shaped, V-shaped, or plural sections filament (Class 313/264)
- Apertured electrode (e.g., grid) supported between two other electrodes (Class 313/265)
- Stem or envelope structure (Class 313/266)