| Year | 1919 |
| Date | 12-Jun |
| Volume | 40 |
| Issue | 946 |
| Page | 476 |
| Category | Electronic |
| Part | 3 |
| Title | Wireless Notes and Developments |
| Author | J.Scott-Taggart |
| Notes | The Vacuum Valve. The three-electrode vacuum tube, curve showing variation of plate current with plate potential, effect of various grid voltages on the plate current |