| Year | 1919 |
| Date | 08-May |
| Volume | 40 |
| Issue | 941 |
| Page | 353 |
| Category | Electronic |
| Part | |
| Title | Wireless Notes and Developments |
| Author | J.Scott-Taggart |
| Notes | The Vacuum Valve, diagram of connections of "valve" permitting a current to flow, no current to flow, circuit in which a Fleming valve acts as a detector |