Voltmeter
before 1974
Electrostatic voltmeter
1888
Self-recording voltmeter, by Richard Freres, 1892-1893
1892-1893
Lord Kelvin's electrostatic voltmeter (vertical type) no. 20623
1913-1920
Hot-wire voltmeter
1895
Direct reading two-range voltmeter
1900
Weston direct-reading alternating and direct current voltmeter
1936
Scalamp electrostatic voltmeter with built-in lamp and scale
1950-1970
Kelvin multicellular electrostatic voltmeter
1892-1900
Voltmeter, centre zero, scale 3-0-3V
Solartron digital voltmeter
1970
Electrostatic Precision Voltmeter made by Trub Tauber
1962
Marconi instruments valve voltmeter
Moving-coil voltmeter in angled wooden stand
1945-1954
Lord Kelvin's electrostatic voltmeter
circa 1880
Ferranti BS1 Voltmeter
1910-1930
Cambridge thermionic voltmeter
1930
Portable standard multi-range moving coil voltmeter
Sensitive electrostatic voltmeter, 1893
1893-1918
Paterson & Cooper Ayrton & Pererry's voltmeter
1900
Avometer model 7 manufactured in 1956
1956
Moving coil voltmeter by Everett, Edgcumbe & Co. Ltd.
Mather electrostatic voltmeter
1890-1910
Digital voltmeter type LM901 serial number 108293 by the Solartron Electronic Group
1960-1965
Electrostatic voltmeter
1893-1920
electronic millivoltmeter Galvamp type 391-2
1966
Lord Kelvin's paralleling voltmeter
Electrostatic voltmeter as used at RAE.
Digital voltmeter
Kelvin's electrostatic voltmeter by White
1892-1899
Cardew's voltmeter, patent, no. 147 (Ediswan)
1890
Sangamo Weston Ltd voltmeter
Early moving coil voltmeter
1889
Silver voltmeter, for international ampere determination
1907-1930
Pocket voltmeter, moving iron repulsion type
1910
Early voltmeter
Voltmeter marked with psychology symbol
1970-1985
Ferranti Cell-testing Voltmeter
1940-1950
One Ayrton-Perry voltmeter
Ayrton-Mather single needle electrostatic voltmeter
1890
Kelvin-White electrostatic voltmeter
1901-1907
Moving-coil voltmeter
1943
Voltmeter and ammeter indicating the direct pull of a solenoid and tubular core
Recording electrodynamometer voltmeter
Pattern K unipivot millivoltmeter
1912
Ferranti voltmeter
1930
Electrostatic voltmeter no 16487.
1913-1947
Moving-coil voltmeter
1951
Electrostatic voltmeter
Ferranti Voltmeter A427F
1920-1950