The electrical method is often used to study avalanches in gases. In this paper a substantial improvement of the time resolution of the measuring system is reported. To release the primary electrons within a very short time a transversely excited atmospheric pressure N2laser with a pulse width of 0.6 ns is used. Secondly the high‐frequency response of the entire circuit is analyzed. As one of the results of this analysis a subdivided cathode is used consisting of a central measuring electrode surrounded by a grounded electrode. The diameter of the circular measuring electrode determines a maximum gap distance for reliable measurements, which can be calculated from a theory of Shockley and Ramo. As an example of the high‐frequency response of our experimental setup avalanches in nitrogen are shown and analyzed. Avalanche measurements in air clearly show a dependence on the humidity, presumably caused by rapid detachment and conversion processes.