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).
Table of results from magneto performance tests.
| Identifier | ExFiles\Box 4\5\ 05-page142 | |
| Date | 1st February 1921 | |
| Handwritten Top Center: X 430 Handwritten Top Right: (Filed 1-2-21) X.430. TABLE OF RESULTS OF MAGNETO PERFORMANCE. (I) | Magneto. | Type and No. | X. No. | (1) Weight (lbs) | (3) Air gap (inches) | (4) H.T. Safety gap (mm). | (6) Platinum gap (inches) | (5) Hertz | Hoke ratio. | Utility test spark lengths (mm) (a) | (b) | (c) | (d) | |---|---|---|---|---|---|---|---|---|---|---|---|---| | Watford. | E.6 40886 | 2375 | 11.7 | .006 | 6.85 | .020 | 30 | .858 | -- | -- | -- | -- | | " | E.6 44258 | 2375 | 11.7 | .006 | 6.85 | .022 | 30 | .861 | -- | -- | -- | -- | | " | E.O.6 46993 | 4181 | 12.7 | .006 (.003 between sleeve and pole shoe). | 7.2 | .009 | 32 | .906 | -- | -- | -- | -- | | -R.{Sir Henry Royce} Bosch. | Z.R.6 2571556 | 427 | 16.25 | .006 | 9.9 | .014 | 36.5 | .458 | 8.5 | 8.3 | 8.1 | 5.0 | | U.S.A. Bosch. | Z.R.6 ch.2998784 | 3916 | 15.1 | .005 | 8.7 | .026 | 37.5 | .850 (Handwritten note below: Slow) | 7.6 | 7.2 | 4.3 | 4.2 | | U.S.A. Bosch. | B.6 3002660 | 3917 | 11.0 | -- | -- | .027 | 35.5 | .846 | -- | -- | -- | -- | | Dixie. | Aero.648 718237. | 3724 | 14.1 | -- | -- | .022 | 38.5 | .407 | 8.0 | 6.5 | 4.0 | 2.5 | | Eisemann. | | 179 | 16.9 | | | | | | | | | | | Conner. | C.M.1 | 4210 | 16.1 | | | | | | | | | | Handwritten note '13' is written above column (c). | ||