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).
Modifying a pocket voltmeter to compare condenser capacities for battery ignition systems.
| Identifier | ExFiles\Box 165\3\ img001 | |
| Date | 2nd July 1918 | |
| To Mr. Coverley. from EFC. x.975 x6033 EFC2/T2.7.18. 2nd. July 1918. X.975 RE POCKET INSTRUMENT FOR COMPARISON CONDENSER CAPACITIES. X.2512 We handed to your Mr. Gamble yesterday afternoon a small 12 volt pocket volt meter. We wish, by re-winding this instrument, to make it more sensitive as a fine range ammeter for the measurment and comparison of low tension condenser capacities in connection with the battery ignition. For this purpose we have explained to Mr. Gamble that we would like this instrument winding with a finer gauge wire and more ballast, so that as a voltmeter the range will be doubled ( so as to read 12 volts when 24 are applied), and as an ammeter it would be decidedly more sensitive. We shall be glad if you will instruct Mr. Gamble to proceed with this work and complete it fairly soon, as we are anxious to have a more correct method of measuring the capacitiy of the condensers we use. Up to the present our measurements have been rather rough. EFC. | ||