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).
The requirements for a change over switch and an ignition switch.
| Identifier | ExFiles\Box 133\3\ scan0115 | |
| Date | 8th January 1940 | |
| -3- Jnr{Charles L. Jenner},1/JH.8,1,40 (15) It was thought that a change over switch for the coils was too much of an elaboration, the wiring on our coils can be changed fairly quickly, (16) A simple ignition switch is required, one which can be left in the locked position. Jnr.{Charles L. Jenner} | ||