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 a rectifying valve for a high-tension voltmeter.
| Identifier | ExFiles\Box 60\2\ Scan070 | |
| Date | 27th January 1931 | |
| X6094. Roy {Sir Henry Royce} /GEA. from EFC. {E. Fowler Clarke - Electrical Engineer} EFCl/AD27.1.31. X.6094. RECTIFYING VALVE FOR H.T. VOLTMETER. With reference to letter ref. WN/WG. {Mr Gill - Financial Director} of the 23rd inst. from the Ediswan Electric Co. the ball gap voltmeter we have is calibrated to read from 0 to 30,000 volts (peak) but the usual voltages we measure are of the order of 10,000. We would prefer a valve suitable for the whole range, if possible. The balls are .7825" in diameter, the gap for 10,000 volts being approximately .100 and for 30,000 - .370. As a matter of interest we should like to know if the B.T.H. U.3 valve which we now understand is completely obsolete, was exactly similar to the G.E.C. U.3 valve, which we have used to some extent but not found entirely satisfactory for our purpose. EFC. {E. Fowler Clarke - Electrical Engineer} | ||