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).
Test results of standard and U.S.A. Bosch ignition coils.
| Identifier | ExFiles\Box 45\4\ Scan026 | |
| Date | 15th September 1922 | |
| X.4079 15.9.22. X.3445. X.4079. X.4275. TEST RESULTS OF STD. & U.S.A. BOSCH IGNITION COILS | Coil. | PRIMARY | | | | SECONDARY | | | | Remarks. | |---|---:|---:|---:|---:|---:|---:|---:|---:|---| | | Resis. (W). | Imped. at 50~ (W). | Reac. at 50~ (W). | Induc. (hys). | Resis. (W). | Imp. at 50~ (W). | Reac. at 50~ (W). | Induc. (hys). | | | 40/50 H.Z. | | | | | | | | | | | 2197. | .866 | 4.30 | 4.22 | .0134 | 5362 | 12000 | 10730 | 34.2 | | | 2209. | .896 | 4.42 | 4.33 | .01378 | 5210 | 12100 | 10910 | 34.7 | | | 149 | .857 | 4.65 | 4.565 | .01432 | 5540 | 14750 | 13680 | 43.5 | | | U.S.A. E.{Mr Elliott - Chief Engineer} | | | | | | | | | | | Original. | .75 | 2.18 | 2.045 | .00643 | 4350 | 14580 | 13900 | 44.2 | p -50.7 x 2 π | | 3075 | .66 | 2.16 | 2.06 | .00655 | 2150 | 8350 | 8080 | 25.7 | p -50.0 x 2 π | | 3076 | .66 | 2.19 | 1.99 | .00632 | 2200 | 8760 | 8490 | 27.0 | " | | 3077 | .64 | 1.97 | 1.86 | .00591 | 2200 | 8590 | 8300 | 26.4 | " | | H.R. | | | | | | | | | | | B1. | .492 | 3.213 | 3.175 | .0101 | 8130 | 18430 | 16550 | 52.7 | Experimentally | | B2. | .482 | 3.11 | 3.08 | .0098 | 9300 | 19800 | 17480 | 55.6 | constructed B Coils | | GB 1 | .631 | 3.131 | 3.065 | .00976 | 4320 | 10310 | 9350 | 29.75 | | | GB 2 | .637 | 3.04 | 2.975 | .00946 | 3890 | 8950 | 8030 | 25.5 | Recd. Feb.1922 | | GB 3 | .627 | 3.03 | 2.962 | .00944 | 3975 | 9720 | 8380 | 26.65 | Low secondary | | GB 4 | .630 | 3.04 | 2.972 | .00946 | 4238 | 9810 | 8850 | 28.15 | turns. | | GB 5 | .633 | 3.15 | 3.085 | .00982 | 3908 | 8850 | 7930 | 25.25 | | | SB{Mr Bull/Mr Bannister} 1 | .610 | 2.89 | 2.822 | .00898 | 7720 | 18510 | 16820 | 53.5 | | | GB 6 | .633 | 2.89 | 2.82 | .00897 | 8500 | 18900 | 15850 | 50.5 | | | GB 11 | .640 | 3.05 | 2.98 | .00948 | 8300 | 19800 | 17980 | 57.2 | | | ||