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).
Comparison of specifications and prices for Smith and Rotax dynamos.
| Identifier | ExFiles\Box 50\1\ Scan033 | |
| Date | 11th February 1921 guessed | |
| -8- Contd. Smith dynamo Type 2D. Quoted quantity price of these dynamos, with all the minor improvements required by R.R. £19.10.0. Weight 34 lbs. This dynamo has output characteristics entirely suited to the 40/50 R.R. car, and the most recently received model is quite silent, on the bench. Rotax dynamo A.T.12. (X.1005). Single price £13.10.0. Weight 27 lbs. Early cutting in point vut low output. Hardly suitable for 40/50 R.R. car but would do well for small car. Well made and finished. Rotax dynamo A.T.4. Single price £12.0.0. Weight 17 lbs. Similar output to A.T.12 but at higher speed. Presumably very suitable for small car. No sample yet obtained. Contd. | ||