A high precision impedance converter system can be a good solution for material defect identification using nondestructive evaluation (NDE). The aim of this work is to introduce the low-cost system for investigation of material defects. The developed system consists of integrated impedance converter circuit which is controlled by microcontroller. A voltage controlled current source is a part of the system too. We are able to detect the material defects by measuring the detection coil impedance. Sensitivity and functionality of our measurement system were verified by using a conductive plate having parameters of the stainless steel SUS316L with conductivity of 1.4 MS/m and relative permeability of 1. The several rectangular defects with accurately defined dimensions were placed on the plate specimen. In our measurement we used the defect with width of 0.25 mm, length of 10 mm and depth of 9 mm. The hidden defect was evaluated too. An aluminum plate was used for these purposes.