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).
Table detailing specifications and modifications for various dynamo models, identified by number or letter.
| Identifier | ExFiles\Box 51\1\ Scan393 | |
| Date | 30th June 1924 guessed | |
| -2- Dynamo. Remarks. Location. Comm. undercut. End plate up-to-date. 470. Fitted with bevelled brushes, EG2. Morgnite. 4-GII. Yes. -- 562. Fitted with pole pieces D.51238, having longer polar embrace. Lab. Yes. Yes. 604. Fitted with pole pieces D.51236, having increased bore. Lab. Yes. Yes. 625. Fitted with pole pieces D.51237, having smaller polar embrace. Lab. No. Yes. J. {Mr Johnson W.M.} Fitted with up-to-date EAC. type expl. brush gear (twin brushes). Lab. Yes. -- K. {Mr Kilner} " " " -- L. " " " -- | ||