From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Hand-drawn wiring diagram showing two different electrical circuit layouts.
| Identifier | ExFiles\Box 59\1\ Scan232 | |
| Date | 31th January 1928 guessed | |
| Left diagram: From dist-box terminal C, To dynamo terminal C, To Earth. Right diagram: To Earth, To dynamo Terminal C, From dial box Terminal C. | ||