Because of the essentially constant percentange resolution and transmission characteristics of electrostatic deflection−type electron energy analyzers, their use in potential modulation−type spectroscopies (such as Auger electron spectroscopy) is problematic, in that it is essentially impossible to choose a potential modulation amplitude capable of yielding anywhere near optimum resolution and/or sensitivity all the way across any wide energy range spectrum. A simple circuit for alleviating this problem is presented and demonstrated.