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).
Observation report on machine singing issues related to bearings and control brush positioning.
| Identifier | ExFiles\Box 36\4\ scan 150 | |
| Date | 21th October 1920 | |
| Contd. -2- EFC5/T21.10.20. same speed and output for different positions of the control brush. These observations were made on a machine with good bearings. A machine was afterwards put on in which the bearings were known to be a trifle slack, but this machine did not sing badly under normal conditions. It could, however, be made to sing with a fully advanced control brush. Singing may always be produced on any E.575 machine by sufficiently advancing the control brush. Operating as a simple shunt wound machine any Lucas E.575 dynamo is quite silent. EFC. | ||