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).
Graph of main-brush position tests on a Goshawk dynamo, plotting ampere output against RPM.
| Identifier | WestWitteringFiles\J\May1923\ Scan35 | |
| Date | 29th March 1923 | |
| IV H/G (29-III-23.) E 7 C MAIN-BRUSH POSITION TESTS OF R GOSHAWK DYNAMO WITH THICK CARCASE AND SMALL AIR-GAP Control brush adjusted in each case, to give a final temperature of from 77° to 80°C at maximum load. Final ambient temperature 21°C. AMPERE OUTPUT DYNAMO R.P.M. CURVE 4 Brushes 4" retarded CURVE 3 Brushes 3" retarded CURVE 2 Brushes 2" retarded CURVE 1 Brushes 1" retarded CURVE N Brushes in neutral position. CURVE 1ad. Brushes 1" advanced CURVE 2ad. Brushes 2" advanced Positions measured circumferentially on carcase from neutral position. Curve labels on graph: 4&3, 2, 1, N, 1ad, 2ad | ||