string galvanometer การใช้

They had taken the string galvanometer and adapted it to record signals from microphones onto photographic film.
Forbes reported the replacement of the string galvanometer with a vacuum tube to amplify the EEG in 1920.
The first human electrocardiogram was recorded in 1887, however only in 1901 was a quantifiable result obtained from the string galvanometer.
The breakthrough came when Einthoven, working in Leiden, used his more sensitive string galvanometer, than the " capillary electrometer " that Waller used.
An initial breakthrough came when Willem Einthoven, working in Leiden, the Netherlands, used the string galvanometer ( the first practical electrocardiograph ) he invented in 1901.