| Year | 1921 |
| Date | 03-Nov |
| Volume | 45 |
| Issue | 1,071 |
| Page | 381 |
| Category | Radio Engineering |
| Part | |
| Title | Crystal Reception |
| Author | Captain H. de A.Donisthorpe |
| Notes | Various types of detectors, auxiliary voltage in crystal reception circuit, an American thermionic valve circuit with a crystal |