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).
Required voltage for a rectifying valve and correcting a filament current specification.
| Identifier | ExFiles\Box 41\2\ Scan031 | |
| Date | 6th November 1926 | |
| To Wd.{Mr Wood/Mr Whitehead} from EFC. X3646 EFC2/T6.11.26. RECTIFYING VALVE FOR HIGH TENSION D.C. INSULATION TESTS. With reference to your WD{Mr Wood/Mr Whitehead}6/NJ4.11.26, I suppose we may presume from the G.E.C. letter that the valve quoted is the nearest one they can offer, though it is made for 40,000 volts reverse, whereas the maximum we should require would be 7,000, as previously stated. We should like to make sure that there is no alternative proposition of a valve of some maximum voltage below 7,000, provided it is not too low. Will you please obtain quotations. A slight error must have crept in somewhere as by your note the filament current was given as 2.5 amperes whereas I think it will be found that this should be .25 ampere. EFC. | ||