1. An electrical system for regulating electrical current flowing from a power source to a load, the electrical system comprising: (a) a current pass regulator element connectable to the power source to control supply current drawn from the power source, (b) a primary voltage multiplying finite output resistance circuit having an input connected to the current pass regulator element and an output connectable to the load, and having a user settable regulated current determining element for determining magnitude of regulated current to flow to the load, (c) a model voltage multiplying finite output resistance circuit including an input connected to the current pass regulator element and an output supplying a model current Imodel, (d) a current sense circuit connected to force an output voltage of the model voltage multiplying finite output resistance circuit to be equal to an output voltage of the primary voltage multiplying finite output resistance circuit, (e) a constant current source for sinking a reference current Iref, and (f) a control circuit responsive to the current sense circuit and the constant current source and connected to control the current pass regulator element to force the model current Imodel to be equal to the reference current Iref, such that current passing through the primary voltage multiplying finite output resistance circuit is regulated at a level established by the user settable current determining element irrespective of input voltage variation of the power source.