Another way of overcoming the problem of a large VSWR is to use a calibrated attenuator. The minimum signal is measured with a minimum value of attenuation. The maximum value is then found, and sufficient attenuation is introduced to reduce the detector reading to the same value as before. (This completely removes any doubts about the detector's characteristics). The VSWR is then simply the volt ratio corresponding to the change of attenuation. Thus if the attenuator is calibrated in dV,