Abstract: A plug in power supply incorporating a ferro resonant transformer mounted on a pair of opposite "E" laminations to provide a low profile magnetic circuit and windings thereon combined with an electronic voltage regulator in which the regulation required therefrom because of the transformer regulation is relatively low and the electronic power component thereof will therefore not be required to dissipate a large amount of power. This enables packaging in a sealed container with a heat sink mounting the power transistor to uniformly distribute the heat thereon and provide a safe plug in power supply.