Methods of measurements of surface electric charges and potentials using electrostatic fieldmeters and voltmeters are discussed. The differences and similarities between those methods are presented. The AC-feedback voltmeter is also described as an unique method that combines advantages of both fieldmeters and voltmeters.

An algorithm based on Fast Hartley Transform (FHT) that uses a digital voltmeter for measuring the harmonic parameters of low-frequency signals with negligible leakage is presented. The algorithm was compared favorably in speed with a previous one based on discrete Fourier transforms.

A quick and accurate method of determining the concentration of carboxyhaemoglobin (COHb) in blood has been developed. The method uses a dual wavelength double beam spectrophotometer in the 1st derivative mode, linked to a digital voltmeter (DVM), with the two beams set 3 nm apart around an isobestic point of reduced haemoglobin (Hbred) and carboxyhaemoglobin at 579 nm. The 1st derivative mode ...

The NIST Industrial Thermometer Calibration (ITC) Laboratory provides calibrations of industrial thermometers over the range from –196 °C to 550 °C. The different types of thermometers include liquid-in-glass (LiG), thermistors, thermocouples (<200 °C), and industrial platinum resistance thermometers (IPRTs). Calibrations are performed by both comparison with a standard platinum resistance ther...