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).
Requesting a modified trembler coil for a battery ignition system, including a hand-drawn diagram.
| Identifier | ExFiles\Box 34\1\ Scan016 | |
| Date | 12th March 1918 | |
| To EFC. from R.{Sir Henry Royce} c. to CJ. c. to EH. X-2512. R5/G12.3.18. X.1520. RE TREMBLER COIL. X.562. X.704. X.3761. X.2512. X.1607. With reference to the trembler on 7-CA this battery ignition now works very nicely, firing the engine at all reasonable speeds, but I want you to send me, preferably a small model coil, with a condenser coupled with very short wires across the trembler platinums, and a trembler of the same pattern, but with slightly shorter iron in the til, arranged to give the quickest movement possible of the iron armature, and a comparatively slow return of the platinum blade. If you cannot send me the small size model coil, send me one of the ordinary size. I am proposing to use this for four-volt little pumping engine here, or if you send me a six-volt one, I will return you the one from 7-CA so that you can make a test of the current. Handwritten notes on diagram: aluminm Space here .05 Space here about 2 to 3 times stiffer than 7CA Space here 1/100 th when at rest Send me at original price. Only one here to go on with R.{Sir Henry Royce} A = 2 B Overall length 3/4 of 7CA | ||