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).
Specifications for two sets of resistance wire for a dimmer switch for instrument lights.
| Identifier | ExFiles\Box 168a\1\ img052 | |
| Date | 12th October 1936 | |
| CAP To Hs{Lord Ernest Hives - Chair}/Wst. BY/RD.2/B.12.10.36. Dimmer Switch for Instrument Lights - RR.Sch.991. On this scheme we have provided 2 sets of Resistance Wire :- 7 1/2 ft. of 24 SWG. .022 dia. Dullray, wound with Macrama String between the turns, or 10 ft. of enamelled or oxide covered, .028 dia. Dullray. In testing these resistances, the temperature may rise when only a small portion of the resistance is carrying most of the current, and we should be pleased if you would watch this point carefully during the test. BY/RD. | ||