Galvanometer Instruments
Many types of chart recorders use a galvanometer to drive the marking device. A light coil of wire suspended in teh magnetic field of a permanent magnet deflects in proportion to the current throgh it; instead of the pointer and scale of a direct-reading meter, the recorder deflects a pen or other marking device. Where greater senstivity and speed of response was required, the mirror galvanomter deflected a beam of light which was recorded photographically.
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Famous quotes containing the word instruments:
“Water, earth, air, fire, and the other parts of this structure of mine are no more instruments of your life than instruments of your death. Why do you fear your last day? It contributes no more to your death than each of the others. The last step does not cause the fatigue, but reveals it. All days travel toward death, the last one reaches it.”
—Michel de Montaigne (1533–1592)