| Year | 1922 |
| Date | 10-Aug |
| Volume | 47 |
| Issue | 1,111 |
| Page | 138 |
| Category | Radio Engineering |
| Part | 1 |
| Title | Some Valve Circuits of 1921 |
| Author | Captain H. de A.Donisthorpe |
| Notes | A valve transmitting circuit, a receiving circuit for limiting and discriminating between different types of signal, a generating circuit for producing oscillations of a low frequency, experimental circuits |