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).
Specifications and testing requirements for two new ignition coil designs.
| Identifier | ExFiles\Box 69\1\ scan0093 | |
| Date | 21th May 1928 | |
| Mr RHG C. EFC. C. Mr Brook X8710 BY/RD3/ML21.5.28. IGNITION COILS - SEC:8140 Please receive herewith blueprints of D.71628/9 representing two ignition coils to enable the following tests to be made, each coil has been arranged so that there is no air space between the case and windings. D.71628 - 25 S.W.G. Primary with 20,000 turns of secondary. D.71629 - 22 S.W.G. Primary with 18,000 turns of secondary. Each of these coils should be tested with single and double length ballast resistances to obtain temperature figures to compare with those given on EFC3/T.11.5.28, this test will also shew whether we have got rid of the phenomenon of hysteresis loss in the moulded material. Will you please have two of each made and we suggest that they be produced by Mr Brock's Dept. on the production machine so that these shall be as near production coils as possible. BY/RD. | ||