Miniaturised instrument for atmospheric electrostatics.
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Intended for weather balloon and robotic aircraft use.
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Includes self-calibration modes for improved accuracy.
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Inexpensive, and fabricated from machine-cut items.
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Addresses the need for climate-relevant measurements.
Abstract
A miniature field meter is described for measuring fair weather electric fields (of magnitude ~100 Vm-1). It is a brushless field mill constructed from machine-cut parts, driven by a computer fan motor. It resolves fair weather fields at ~1 mV per (Vm−1), with a time response of 0.65 s. It implements self-calibration through combining a mechanical shutter with a programmable bipolar calibration electrode. It has a mass of 86 g, dimensions 4 cm × 4 cm x 8 cm and consumes <100 mA at 6 V. This design will facilitate new climate-related measurements using balloons and remotely piloted aircraft.