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).
Test results for a Watford E.W.6 Magneto, serial number 127221, for chassis number 27-EX.
| Identifier | ExFiles\Box 65\3\ scan0438 | |
| Date | 15th January 1931 | |
| X7791 15.1.31. X.7791. WATFORD E.W.6. MAGNETO No. 127221. CHASSIS NO. 27-EX. Tested 1.10.30. Passed at 120 Revs. } 5.5 mm. gaps. 160 " 190 " D.Ellis. | ||