| Answer | Crossword Clue |
|---|---|
| triodes | vacuum tube containing three elements, usually anode, cathode, and control grid |
| triode | vacuum tube containing three elements, usually anode, cathode, and control grid |
| tetrode | a vacuum tube with a cathode, an anode, a control grid, and an additional grid or other electrode |
| tetrode | vacuum tube containing four electrodes, usually a plate, two grids, and a cathode |
| tetrodes | vacuum tube containing four electrodes, usually a plate, two grids, and a cathode |
| pentode | vacuum tube having five electrodes, usually a plate, three grids, and a cathode, within the same envelope |
| pentodes | vacuum tube having five electrodes, usually a plate, three grids, and a cathode, within the same envelope |
