Vector Voltmeter for High-Precision Unbalanced Comparator Bridge

A new inductance comparator bridge has been constructed at the Institute of Measurements, Electronics, and Automatic Control (Gliwice, Poland) for the calibration of inductance standards in the frequency range of 100 Hz-10 kHz. Since the instrument belongs to the class of unbalanced transformer bridges, very accurate measurement of the voltage on the diagonal of the bridge is required. A vector voltmeter which enables the precise measurement of both components of the unbalance voltage is described in this paper. We report on the realization and characterization of the voltmeter which is an integral part of the new inductance comparator bridge.