313 / | HD | ELECTRIC LAMP AND DISCHARGE DEVICES |
326 | DF | ELECTRODE AND SHIELD STRUCTURES {14} |
348 | ![]() | .~ Foraminous electrodes (e.g., grids) or shields {2} |
349 | DF | .~.~> Nonuniform mesh area or nonstraight electrodes or nonuniform cross sectional area electrodes |
350 | DF | .~.~> Rods, wire, or mesh supported on rod or post |