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).
Graph showing curves of spark-lengths and current consumptions for Coils G.B.S. and S.B.I.
| Identifier | ExFiles\Box 52\3\ Scan068 | |
| Date | 21th December 1932 | |
| X44381 CURVES of SPARK-LENGTHS and CURRENT CONSUMPTIONS. OF COILS G.B.S. and S.B.I on 10 VOLTS (APPROX), WITH GOSHAWK BALLAST AND DISTRIBUTOR. CONDENSER ROLLED PAPER, CAPACITY .45 mF. NOTE. Spark readings taken on single gaps. GAP (M {Mr Moon / Mr Moore} /m) CURRENT (AMPERES) DISTRIBUTOR SPEED (R.P.M.) Points marked △ - Current through coil S.B.I. " " ☉ - " " G.B.S. " " Y - Spark-length from coil S.B.I. Current reversed. " " ▽ - " " " " " " normal. " " ☐ - " " G.B.S. " reversed. " " X - " " " " " normal. F.J.A | ||