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).
To Mr. Brock regarding the addition of a secondary winding of 18000 turns to a standard coil.
| Identifier | ExFiles\Box 69\1\ scan0085 | |
| Date | 8th May 1928 | |
| To Mr. Brock. X8710 EFC3/T1 8.5.28. We hand you herewith an old standard coil wound with primary only. Will you please have the secondary winding wound on 18000 turns, this being the figure for the previous standard tall coils. The order number for this job is 54733. EFC. | ||