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).
Trial and development of a new 6-volt coil compared to the standard 4-volt version.
| Identifier | ExFiles\Box 34\1\ Scan001 | |
| Date | 31th October 1913 | |
| X.2512 R8/P31.10.13. To Wor.{Arthur Wormald - General Works Manager} from R.{Sir Henry Royce} c. Mr. Ellis. c. J.{Mr Johnson W.M.} ______ X.562 - RE 6 VOLT COIL MADE IN WORKS X.1607. X.2512. X.186. I think the 6 volt coil of our own make, which will enable us to use half the lighting accumulators at a time can be looked upon as being a success, and I think we might make a number of these for further trial. They should be clearly marked that they require six volts with a current of one ampere. Our standard ones take 4 volts and 1¼ amperes which is just the same energy, but of a less convenient voltage. I think Mr Ellis might go on varying the primary winding and the condenser until he gets a definite result one way or the other, because the two coils which have been compared suggest to my mind that there is more in the exact arrangement of the trembler than the variation due to the winding. For instance, No.2. coil, which has the finer primary winding and the greater number of turns, gives the longer spark. The increase of the number of primary turns should make the coil slower in its action and the platinums last longer. It would of course be less vigorous, as stated, but if it were not too slow, my impression is that the platinum points should last better. R.{Sir Henry Royce} | ||