= Oscillograph
{wiki}
An <oscillograph> traces or records an electrical <signal> against <time>, making its waveform observable. The signal-to-deflection conversion and the time-axis mechanism require separate calibration.
A historical string design passed <electric current> through a fine wire in a <magnetic field>. An illuminated image of the wire and a rotating <mirror> made its <oscillation> visible on a screen. <General Radio type 338 string oscillograph by the Smithsonian Institution>[Smithsonian, General Radio type 338 string oscillograph: wire, lamp and rotating-mirror arrangement]{ref} <Resonance> and <inertia> limit how faithfully such a recorder follows rapid signals; a distorted trace need not reproduce the input waveform.
Back to article page
