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).
The required resistance for reduced charge switching, specifying the length and gauge of Eureka wire needed.
| Identifier | ExFiles\Box 163\6\ img018 | |
| Date | 7th March 1930 | |
| X6016. 7.3.30. X.6016. REDUCED CHARGE SWITCHING. We have today informed Ry/RD. that the required resistance in connection with the above is 3'6" of No. 26 SWG. bare Eureka wire. EFC. | ||