Unavoidable gridshock without scrambling circuitry from a faradic source of low-radio-frequency current

A high-voltage radio-frequency stimulator was used as a source of motivational footshock in studies of conditional suppression. The circuit of the stimulator is presented schematically, then discussed in terms of affect induced by, gross behavioral response to, and electrical characteristics of, the stimulus. Near daily use of the stimulator across 6 months of formal assessment revealed that nonscrambled presentations of footshock via a grid of aluminum bars invariably resulted in stimulation of rat Ss and generated highly efficient conditional suppression of operant responding. While the stimulator was primarily designed to permit unconfounded presentation of gridshock in a 2,450-MHz microwave field, its simplicity and reliability suggest application in other situations requiring motivational shock.