The electrochemical noise diagnostic became a firm component of pretentious corrosion investigation in the last few years. This was, as well as on other scientific fields, finally enabled by the effort of digital measuring equipment and more efficient microelectronics and computer components. Thereby it became possible at all to evaluate the data with different methods, to represent and file them. The methods for evaluation are very versatile and should be choosen in dependance to the testing problem and the limiting conditions. In this case, an important context exists between the measuring methodology, the used measuring equipment and the digital data acquisition. Some of these interrelations are shown in this paper.