Abstract: A method of fabricating an autotransformer ballast and the unique ballast resulting therefrom are disclosed; the method comprising forming a single bobbin for accommodating a main primary winding and a main secondary winding, each having a large number of turns, and additional, filament windings, each having a number of turns much smaller than the turns of said first and second main windings; the bobbin being defined by a tube adapted to accommodate a core, the tube being divided into sections along its longitudinal axis for receiving the respective windings; the method further comprising the steps of continuously forming the windings around the bobbin with wire of the same size for all of the said windings.