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).
Graph plotting an unlabeled vertical axis against two horizontal axis scales: 'Secondary Kilo-Volts' and 'Primary Current Amps'.
| Identifier | ExFiles\Box 164\5\ img369 | |
| Date | 12th July 1938 guessed | |
| PRIMARY CURRENT AMPS, 0.8, 1.6, 2.4, SECONDARY KILO-VOLTS, 2, 4, 6, 40, 80, 120, 160 | ||