Is joule thief circuit gets overunity?

[ltseung888]

The configuration if you have two oscilloscopes is attached.

Note that we need to cater for the common ground for both Oscilloscope A and Oscilloscope B.  Thus DSO 1 Ch1 -ve, Ch2 -ve and DSO 2 Ch1 -ve and Ch2 -ve need to be at the same point.

The actual Input is not across the battery.  It includes the drop across the 1 ohm resistor.  We can add that back in with the oscilloscope analysis.  In addition, the current measurement for Input (A3 and A4) should be inverted.

With the two scopes, both Input and Output can be captured at the same time (within the finger pushing timeframe ).

[ltseung888]

Please compare the two scope configuration diagram on the previous post with the markings on the board 38 to be shipped.
If you have only one 2 channel DSO, do the Input measurement first and then the Output measurement.  The test to choose will be steady condition that can still demonstrate OU.  These cases will be described in detail in the coming posts.

[hartiberlin]

Okay, many thanks Lawrence.
Looking forward to test your board.

Regards, Stefan.

[e2matrix]

I have only looked briefly at the latest info here but I'd like to bring up a test I did some time back and am replicating this moment to check my memory of it.  It involves a 1 farad capacitor and a 5 mm bright LED.   That's it - no other parts.   I charge the cap up to about 4 volts by briefly touching it several times for just a couple seconds each across a small 9 volt battery.  I then hook up the LED.  It shines bright for a few minutes and slowly starts to dim down.  I'm retesting now to see how long it stays lit but in a past test some years ago I recall it was still lit after 5 or 6 hours. 
In the Joule thief above a 10 Farad cap is being used versus my 1 Farad cap.  I'm not saying there is nothing of interest with the JT but my setup has had the LED running steadily for hours.   Also my 1 Farad capacitor is very close to the size of the wound 1" toroid used in many JT's.   Just some food for thought. 

[ltseung888]

Oscilloscope Analysis results for Board 39 for Energetic Forum. 
This board also showed Average Output Power > Average Input Power without the capacitor.  These boards were hand-built by the same professional.  His comments: "I checked all boards before giving them to you.  You do not see the failed ones."
The COP from my test is -1.93.  The negative sign came from Input, implying a feedback circuit.  To save space on this forum, I do not show the xls file but show the comparison Output Power vs Input Power graph instead.  Those interested in the actual xls file can pm me.