fed from switch 12 to one side of a conventional ignition transformer 30 at a junction point 34 of its primary winding 31 and its secondary winding 32 the other side of primary winding 31 is connected to a junction point 26 of an output winding 25 of an output or coupling transformer of non dc power source 20 and the other side of winding 25 is connected to a junction point at 27 to which one side of capacitor 40 is connected the other side of a capacitor 40 being at ground potential 11 the winding 25 and hence power source 20 is in series connection with transformer primary 31 and capacitor 40 power source 20 may have a rectangular wave output therefrom though other waveforms are possible if desired power source 20 will generally be a transistor type power generator having waveform repetition rates ranging between 2khz and 10 khz and be transformer coupled through other coupling instead of the output transformer of which winding 25 is illustrated may be used if desired a schematic of the circuit comprising power source 20 and details as to its operation is old in the art and for example may be found in bulletin tc 101b entitled tape wound cores published by arnold engineering company of marengo illinois at pages 45 and 46 and including fig2 thereof and a copy of such bulletin is available in the search room of the united states patent and trademark office such bulletin being copyrighted in 1972 by arnold engineering company junction point 26 is connected by wire to an electrical contactor 53 cooperating with the periphery wheel or disk as at 51 of timer 50 driven in a clockwise direction as illustrated by the arrow thereon timer 50 comprises an electrically conductive.