| Year | 1921 |
| Date | 24-Nov |
| Volume | 45 |
| Issue | 1,074 |
| Page | 455 |
| Category | Radio Engineering |
| Part | |
| Title | A Simple Amplifying and Detecting Unit |
| Author | Captain H. de A.Donisthorpe |
| Notes | Photograph, connections, four-way sockets & leads, front elevation, side elevations |