Letter from Joseph Lucas Limited discussing the technical specifications of a Q12 type non-ballasted coil.
| Identifier | ExFiles\Box 164\5\ img117 | |
| Date | 30th December 1931 | |
| REGISTERED OFFICES & GENERAL DEP'TS GREAT KING STREET, BIRMINGHAM LONDON OFFICES & SHOWROOMS 319, REGENT STREET, W.1. TRADE MARK X6018 LUCAS 'KING OF THE ROAD' LAMPS LUCAS STARTING & LIGHTING EQUIPMENT FOR CARS, LUCAS LIGHTING EQUIPMENT FOR MOTOR CYCLES, LUCAS MAGNETOS, LUCAS BATTERIES JOSEPH LUCAS LIMITED ELECTRICAL DEPARTMENT WELL STREET BIRMINGHAM TELEPHONE: NORTHERN 5201 (12 LINES) TELEGRAMS & CABLES: 'LUCAS, BIRMINGHAM' SERVICE DEPÔTS BELFAST 3/5 CALVIN STREET, MOUNT POTTINGER. BIRMINGHAM GREAT HAMPTON STREET. BRIGHTON OLD SHOREHAM RD., HOVE. BRISTOL 345 BATH ROAD. CARDIFF 54 A. {Mr Adams} PENARTH ROAD. COVENTRY PRIORY STREET DUBLIN PIMLICO STREET. NORTH CIRCULAR ROAD. EDINBURGH 32, STEVENSON ST. {Capt. P. R. Strong} GORBALS GLASGOW 227/229 ST GEORGES ROAD. LEEDS 64, ROSEVILLE ROAD SERVICE DEPÔTS LIVERPOOL 480/486 EDGE LANE. LONDON GORGES ROAD, ACTON VALE W.3 LONDON 759, HIGH ROAD, TOTTENHAM, E.10. LONDON 319, REGENT ST. {Capt. P. R. Strong} , W.I. SHOWROOMS & OFFICES. LONDON 155, MERTON ROAD, WANDSWORTH, S.W.18. MANCHESTER 291/293, DEANSGATE AND STORE STREET DEPOT. MANCHESTER TALBOT RD. STRETFORD. NEWCASTLE-ON-TYNE 64/66, ST MARY'S PLACE. WHEN REPLYING PLEASE REFER TO EAW/EE 30th December 1931. Messrs. Rolls-Royce Limited, DERBY. Attention of Mr.West. Dear Sirs, Further to the writer's recent visit to Derby, and our discussion re Coil Ignition generally, we are sending you, under separate cover, one of our standard non-ballasted coils, type Q12, in case you may care to make some tests on this. This coil has a resistance of 4.3 ohms cold, and 6.6 ohms after 1 1/2 hours on 12 volts. When cold it requires a current of .99 amperes to give 10 KV on open circuit, using a primary condenser of .12 Mfd. capacity. The corresponding current, when hot, is 1.07 amperes. The primary inductance of this particular coil was not measured, but the figure for this type of coil ranges from 18 to 20 MH. {M. Huckerby} The damping, as determined by the ratio from the second to the first voltage peak was 76% cold, 70% hot. Yours faithfully, JOSEPH LUCAS LIMITED. E.A. Watson ES | ||
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).