To study the electrical properties of solid ionic conductors with a spatial resolution we developed a novel variant of the impedance technique based on the two-dimensionality of the cell-electrodes arrangement and resulting frequency dependent penetration depth of the excitation signal, ie the electrical signals spread deeper into the ionic conductor the lower the frequency. The technique was quantitatively verified by detecting the position of an additional Ag strip added to the ionic conductor. Using the advantage that at high frequencies only the region close to the working electrode is probed, the technique was used to study parent metal/ionic conductor contacts. In this context resistance and capacitance of the Ag/AgCl interface were measured and analysed in the light of ionic space charge effects. The difference of the described technique, when compared with the conventional impedance analysis, consists in the fact that the measured decay rate of electrical relaxation now includes also the information about the position in space at which the relaxation occurs.