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).
List of parts required for a modification to use 3.5 volt bulbs in series for lampholders.
| Identifier | ExFiles\Box 168a\1\ img073 | |
| Date | 8th April 1937 | |
| -2- BY/RD./B.8.4.37. Cont'd.{John DeLooze - Company Secretary} For economies sake, we propose to use 3.5 volt bulbs in series, to RP.Sch.1041, and the pieces required are as follows :- Lampholders for 3.5 v.{VIENNA} & 16 v.{VIENNA} Bulbs. :- New Parts required :- D.75875 - Contact - Outer. 8 off. D.75876 - Link. 8 off. D.75877 - Contact Spring. 8 off. D.75884 - Assembly of Instrument Lamp. 3.5 volt Bulbs. (M.E.S.) 6 off. Standard Parts required :- DB.{Donald Bastow - Suspensions}314 - Lamp Casing. 8 off. (7 extra). DB.{Donald Bastow - Suspensions}317 - Insert - Lamp Casing. 16 off. (14 "). L.255 or S.7954 - 16 v.{VIENNA} Bulb. Indicator Patt. 2 off. (6 less). Stock Parts :- K.1655A - 7 BA. Ch.Hd.{Mr Hayward/Mr Huddy} Screw. 16 off. (14 extra). K.4451A - 7 BA. Plain Washer. 16 off. (14 extra). K.9002A - 7 BA. Spring Washer. 16 off. (14 extra). Will Rm{William Robotham - Chief Engineer}/Wst., please let us have information about the kind of resistance required to reduce the volts to 10.5 Handwritten notes: 6 ohms 7.5W BY/RD. | ||