Letter from American Bosch Magneto Corporation detailing the resistance of TC-30 and TC-31 ignition coils.
| Identifier | ExFiles\Box 61b\4\ scan0106 | |
| Date | 2nd December 1928 | |
| AMERICAN BOSCH MAGNETO CORPORATION Springfield, Massachusetts December 2, 1928. Rolls-Royce of America, Inc., Springfield, Mass. Att: A. {Mr Adams} C. Ross, Pur. Agt. Gentlemen: Answering your letter of November 29th, we are glad to advise you that the resistances in ohms of the primary and secondary windings of our TC-30 and TC-31 ignition coils are approximately as follows: Primary Secondary 6 Volt - TC-30 1.25 4700 12 Volt - TC-31 4.2 7000 We allow a tolerance of ±0.1 ohms on the primary and ±1000 ohms on the secondary. Yours very truly, AMERICAN BOSCH MAGNETO CORPORATION F. {Mr Friese} N. Perry. | ||
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).