| Year | 1939 |
| Date | 31-Aug |
| Volume | 81 |
| Issue | 1,999 |
| Page | 259 |
| Category | Nautical |
| Part | |
| Title | A Revolution Counter for Model Speed Boats |
| Author | Edgar T.Westbury |
| Notes | Photograph of the flashing counter, construction, electric circuit, another view, attachment, scope of application |