In a transmission path having two discrete-value adjustable amplifiers, a first amplifier is set with a first gain factor and a second amplifier is set with a second gain factor. A signal is then applied to an input of the transmission path, and a level of a first output signal of the transmission path is ascertained and the second gain factor is altered. The first gain factor is changed in the opposite direction, so that a total gain factor of the transmission path remains substantially the same. The level of an output signal from the transmission path is then ascertained again with the new settings. An offset value is determined by comparing the levels of the first and second signals. As a result, the second amplifier can be calibrated using relative measurements and the first amplifier.