Abstract: The invention involves storing information about the probe frequency response in the probe itself. The information preferably consists of a set of one or more characteristic frequency response data points. Each data point includes at least the gain of the probe at a given frequency. More preferably, each data point includes the complex transfer characteristic of a probe (S21 in FIG. 2) and optionally the complex output reflectivity of the probe (S22 in FIG. 2) and the frequency (F in FIG. 2) at which the data applies. A variable number of frequency points can be stored, as necessary, to adequately describe the probe's response. The probe also preferably stores a header containing the number of stored data points. The invention readily extends to probes having multiple gain settings or multiple bandwidth settings, by simply storing multiple sets of S21, S22 and F data.