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Hello all again. I have more detailed data of my own joule thief. I have it running on a variable power supply in order to get some measureable data from it. I have my scope hooked up across a 1 ohm carbon resistor(non inductive) to get a more complete view of the incoming current envelope. My toroid is a 7/8" dia. X 1/4 " thick ,I.D., 1/2 ". It is wound with 100 turns of #28 enameled wire, with two additional windings of 20 turns of #26 wire wound wire each. Using a 2N3904 transistor fed into one of the 20 turn windings and the other winding feeding a 1 K resistor into the base of the 2N3904. I have two white LEDS of 7000 mcd intensity connected across the emitter and collector of the transistor.With no load on the 100 turn winding, input waveform is a triangular wave of 28 ma @307 khz with 0.795 volts in. The leds are lighting with a peak voltage of 6.42 v peak and output of unloaded 100 turn coil is 41.6 v peak to peak, positive excursion is 30.8 v peak, negative is 10.8 v peak. I then connected up the same type of leds, five of them to a 100 ohm resistor to a 33 uf cap fed thru a 1N914 diode from the 100 turn winding.I get 15.3 v pos peak and 9.0 v neg peak, with 13.98 volts across the cap.With .025 volt across the 100 ohm resistor. That is 3.5 mw of power. Input power is 0.795 volts X 28 ma/2(triangular wave)=11 mw. efficiency is input/output=3.5/11=31.8%. I never expected any over unity power from this type of circuit but it is still fun to play with , making different changes to windings and loads to push the envelope. I think I have pushed the envelope as far as I can with this circuit, still admiring it and it still reminds me of the hartley oscillator used in radio work. I have been working with different oscillators for years and never thought about this application of it before and thank the person who created the original joule thief , for out of the box thinking. Still looking forward to new ideas in this arena but I will now move on to my experiments using a large ferrite core for a MEG generator desgn. My wishes of success for those continuing to seek out energy solutions.