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).
Order specifications for an A.T. Speedometer revolution counter.
| Identifier | ExFiles\Box 50\4\ Scan102 | |
| Date | 1st February 1927 | |
| To Wd. {Mr Wood / Mr Whitehead} from Hs {Lord Ernest Hives - Chair} /Rm. {William Robotham - Chief Engineer} X4308V Hs {Lord Ernest Hives - Chair} /Rm {William Robotham - Chief Engineer} 5/LG1.2.27. A.T. SPEEDOMETER. Will you please order for us from the A.T. Speedometer Co., 1 revolution counter to record from 0 to 4000 revs. per minute. We should prefer 0 to 3500 r.p.m. if they can supply. From their letter however, apparently this is not obtainable. Suggest you enquire please. The end fittings to be made to Sch.728. The face to be of the same dimensions as those of the speedometer. As the shaft from which the rev. counter will be driven runs at one and half times engine speed, in order to read engine revs. per min., the ratio for the instrument should be .66 to 1. The A.T. Speedometer people already have our Scheme 728. We attach their letter for your information, which please return. Length of Cable 6ft 6" Hs {Lord Ernest Hives - Chair} /Rm. {William Robotham - Chief Engineer} | ||