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).
Experimental record sheet for an American Bosch ignition coil.
| Identifier | ExFiles\Box 61b\4\ scan0124 | |
| Date | 19th April 1926 | |
| Y4275 ELECTRICAL EXPERIMENTAL RECORD SHEETS Type TC30 [R.R. car] X. &No.:- 4275 American Bosch ignition coil as used on U.S.A. Date on. | Location. | Date off. | REMARKS. | Miles reading start. | Miles reading finish. | Miles covered. | Total miles. --|---|---|---|---|---|---|-- 23-10-26 | lab | | Examined, resistances and inductances of windings determined (See WB{Mr Brazier/Mr Bell}109) | | | | 26-4-27 | lab | 12-5-27 | Tested on Bench for 10000 mls with U.S.A Bosch distributor. Failed partially after 7,800 miles. | | | Bench | 7800 20-5-27 | West WitteringHenry Royce's home town | | Coil opened up and sent to W.W. for inspection. (See WC15/19-5-27). | | | | 19.4.26. | ||