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).
Instruction to alter the old standard double value ballast resistance by shortening the working wire length.
| Identifier | ExFiles\Box 168a\5\ img044 | |
| Date | 19th February 1929 | |
| X.7720 BY.{R.W. Bailey - Chief Engineer} from EPC. c. to BY/RD. EFC3/LG19.2.29. BALLAST RESISTANCE. Will you please issue instructions to those concerned for an alteration to the old standard double value ballast resistance in cases where this is found to be unsatisfactory, by which the working length of the wire is lowered from 39 inches to 34 inches, thus making it the equivalent of the new 1 1/4 value ballast resistance recently instructed for production. EPC. | ||