Automatic impedance bridge
B. Mollet · Digital Access to Libraries (Université catholique de Louvain (UCL), l'Université de Namur (UNamur) and the Université Saint-Louis (USL-B)) · 1975
An automatic impedance bridge accurate within 0.1% for frequencies from 0 to 20 kHz is described. The basic technique used is frequency conversion governed by a phase locked loop. Bridge balance is achieved electronically by use of digital to analog converters and phase sensitive detection. The cost of the system is held low in comparison with other commercial versions with somewhat lower performances, this being due to the use of cheap, run of the mill components. Measuring speed (10 per second) is suited to many industrial applications such as component check.