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).
Extract from Mr Archer's report regarding tests on coil and ballast configurations.
| Identifier | ExFiles\Box 45\4\ Scan055 | |
| Date | 30th October 1922 | |
| Extract from Mr Archer's report on the way to London. X.4079.a 30.10.22. On my way down I tried the coil with the 18,000 turns and with the 20" ballast. This is quite O.K. With the 32" ballast sometimes it is possible to make it misfire picking up, but impossible to make it fail entirely. It would seem that this coil is as good as a 40/50 with the 20" ballast. The 18,000 turn coil with 20" ballast takes 1.8 amps, with 32" ballast 1.5 amperes, which is the same as the 40/50. I am going on with the coil testing and if nothing better turns up I shall fit the 40/50 coils and 20" aballast to the four coils. L. Archer, | ||