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).
Letter to The General Electric Co. Ltd. regarding issues with under-performing double contact inspection lamp bulbs for experimental cars.
| Identifier | ExFiles\Box 166\4\ img097 | |
| Date | 22th January 1931 | |
| X608A EFC2/AD. 22nd January, 1931. The General Electric Co.Ltd. 34/35 Moor St.{Capt. P. R. Strong} Birmingham. Dear Sirs, Double contact inspection lamp bulbs. Referring back to yours ref. O/P/466 of the 1st inst. we duly received the type S.7214 lamp bulbs and these have been tried out in use in the inspection lamps of our experimental cars. It is reported that these bulbs are not sufficiently bright to work with and it appears that what is required is a bulb of similar voltage to the S.7168 but of greater wattage say 9 or 12. The size of the bulb must not be appreciably greater otherwise the bulbs will not go inside the protecting cages. It is understood from our testers that there has not previously been similar trouble with the S.7168 bulbs which would suggest that a batch of these have been made for rather lower voltage. We should be pleased to have your remarks as to any other possibilities. The entry on our list of standard lamp bulbs at present standardised is Inspection lamp bulb. 12/14 v.{VIENNA} 6 w. vacuum, double contact. S.B.C. cap. BAS.10.D. (Osram No. S.7168) | ||