| 313 / | HD | ELECTRIC LAMP AND DISCHARGE DEVICES |
| 364 | DF | CATHODE RAY TUBE {11} |
| 441 | DF | .~ Ray generating or control {6} |
| 446 | DF | .~.~ Including cathode assembly {2} |
| 447 | DF | .~.~.~ With control grid adjacent cathode {1} |
| 448 | | .~.~.~.~ With anode {1} |
| 449 | DF | .~.~.~.~.~> With additional electrode {2} |