Vector impedance measurement is necessary for studying the characteristics of electronic circuits as well as electrical networks. A recently developed technique to measure the vector impedance is based on measuring three voltages and then calculating the vector impedance. Therefore this technique is suitable for computer based measuring systems. It is only required to measure three voltages and the computer carries the rest. Peak detectors used to convert the ac voltages into dc voltages have limited bandwidth and accuracy. Therefore to make the measuring set up more useful and more economical, the frequency range has to be enlarged. The test signal is generated by the computer, which also controls the whole set up.