Abstract: In an exemplary embodiment, in order to operate the X-ray diagnostic generator with a decreasing (or "falling") load during an X-ray exposure, there is disposed in the primary circuit of the high voltage transformer a bridge rectifier in whose D.C. current branch there is disposed a series of networks each consisting of at least one resistance and one capacitor in parallel, and a switch for the purpose of switching the network into and out of the circuit. A timing control initially short circuits the resistance-capacitance networks to provide for maximum primary current at the start of an exposure, the shunt capacitor absorbing such primary current when each resistance-capacitance network is first switched into the circuit to initiate a relatively smoothly decreasing primary current as a function of time. As secondary voltage tends to decrease, the X-ray tube current is progressively reduced to maintain the selected X-ray tube voltage, the result being the desired smoothly decreasing load characteristic.