Implementing a simple vectorial bridge with a digital oscilloscope

We show how to exploit instrumentation available in undergraduate student laboratories to build a simple vectorial bridge. In particular, we take advantage of the ability to read data from a digital oscilloscope with a personal computer and describe an algorithm to obtain an accurate evaluation of the phase difference between two sinusoidal signals. The use of the bridge to characterize components of a high-Q RLC filter is shown to greatly improve the understanding of results in electrical resonance experiments. Direct evidence of dielectric losses, skin currents, and the effect of distributed capacitance is obtained.