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).
Comparison drawing of a proposed and a standard dynamo slot and tooth for different winding gauges.
| Identifier | ExFiles\Box 62\3\ scan0177 | |
| Date | 5th February 1931 guessed | |
| X. 6106. .150 .600 .460 .166 .517 .535 .064 .094 Proposed } Necks Standard } 20/25 DYNAMO Proposed slot and tooth for 18 swg winding superposed on Standard slot and tooth for 19 swg winding. | ||