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).
Graphs showing commutator distributor primary current curves at different RPMs with advanced and retarded brush timing.
| Identifier | ExFiles\Box 168\3\ img155 | |
| Date | 5th April 1938 | |
| COMMUTATOR DISTRIBUTOR PRIMARY CURRENT CURVES V.Ch.8 850 R.P.M. NEGATIVE BRUSH ADVANCED AMPS 2 1 0 850 R.P.M. NEGATIVE BRUSH RETARDED AMPS 2 1 0 S.G.L. 5.4.38 2250 R.P.M NEG. BRUSH ADV'D AMPS 2 1 0 2250 R.P.M NEG BRUSH RET'D AMPS 2 1 0 | ||