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).
Test and calibration data for a Weston A.C. Milliammeter No. 1068.
| Identifier | ExFiles\Box 33\4\ Scan234 | |
| Date | 16th March 1927 guessed | |
| X/782 WESTON A.C. MILLIAMMETER NO.1068. Resistance of instrument at 16° C = 296 ohms. " " 300 V multiplier = 9710 " " " 300 V range = 10006 " " " 30 V multiplier = 717 " " " 30 V range = 1013 " Reading. | Milliamperes. | Volts (300 V range) | D.C. Volts (30 V range) | A.C. volts (30 V Range). 10 | 9.88 | 98.9 | 10.01 12 | 11.88 | 118.9 | 12.03 14 | 13.89 | 139.0 | 14.07 16 | 15.89 | 159.0 | 16.10 18 | 17.89 | 179.0 | 18.12 20 | 19.92 | 199.3 | 20.18 22 | 21.96 | 219.1 | 22.25 24 | 24.00 | 240.1 | 24.31 26 | 26.05 | 260.7 | 26.39 28 | 28.11 | 281.3 | 28.48 30 | 30.18 | 302.0 | 30.57 EFC. [Stamped text, right side] EMG. 'd 8200 ROLLS-ROYCE LIMITED Independently confirmed to be exactly as for d.c. | ||