vibrating-reed electrometer

measurement instrument

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Last updated

July 14, 2026

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The vibrating-reed electrometer is a type of electrometer, an instrument designed to measure very small voltages and currents. This specific type of electrometer uses a capacitor with a vibrating reed as one of its plates. The movement of this reed alters the voltage across the capacitor. The electrometer's output is the current needed to maintain a constant capacitance, and this output can be easily amplified without drift. Electrometers, in general, have various uses, including studying cosmic rays, chemical analysis, and gas chromatography.1

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electrometer
The vibrating-reed electrometer uses a capacitor that has a vibrating reed as one of its plates. Movement of the reed changes the voltage across the capacitor. The output of the electrometer (which is easily amplified without drift) is the current necessary to keep the meter’s capacitance…
Read More
The vibrating-reed electrometer uses a capacitor that has a vibrating reed as one of its plates. Movement of the reed changes the voltage across the capacitor. The output of the electrometer (which is easily amplified without drift) is the current necessary to keep the meter’s capacitance…
Read More

mass spectrometry
Faraday cup
…was the introduction of the vibrating-reed electrometer that allowed isotopic ratios to be routinely measured to a few parts in a hundred thousand. For more than three decades, these electrometers functioned unsurpassed as laboratory workhorses and were only slightly modified in design. They can now be equaled and in some…
Read More
…was the introduction of the vibrating-reed electrometer that allowed isotopic ratios to be routinely measured to a few parts in a hundred thousand. For more than three decades, these electrometers functioned unsurpassed as laboratory workhorses and were only slightly modified in design. They can now be equaled and in some…
Read More