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).
Voltage measurements taken on an old type ignition coil with different secondary winding connections.
| Identifier | ExFiles\Box 69\1\ scan0324 | |
| Date | 19th May 1930 | |
| X8710 WE.25. 19.5.30. X.8710. X.918. VOLTAGES ON IGNITION COIL WINDINGS. Measurements of the primary voltage of an old type ignition coil with an insulated secondary have been made with the inside end of the secondary either connected to the beginning or the end of the primary. The results show that with the secondary connected the normal way a voltage of 550 volts could be obtained across the primary terminals and with the inside end of the secondary connected to the inside end of the primary, 730 volts i.e. 180 volts increase. EFC/HEW. | ||