Wheatstone bridge for admittance determinations of highly conducting materials at low frequencies

The determination of reactive properties requires the use of sensitive bridge techniques, whenever the reactance is very small compared with the resistance. The following article describes an accurate Wheatstone bridge which permits resistance and reactance determinations within the frequency range from 10 to 200,000 cycles per second. The maximum accuracy for resistance determinations is one part in 10‾7 the accuracy for reactance depends on frequency and power factor. The various inductance values of the resistance coils cause negative capacities, which are especially high when the resistance values are smaller than 100 ohms. A simple and accurate technique for determination of these capacities is described.