Is joule thief circuit gets overunity?

[Void]

It would be interesting if you could equate the output impedances of the psu and the cap somehow, but I have no idea how to do this. It hardly seems fair to have to put a resistor in series with the supercap. It certainly looks like you are getting more ringing with the PSU, and this is a loss mechanism.

I am not sure what you mean about the resistor in series with the super cap, as this one ohm series resistor is exactly the same when using the regulated power supply, and both setups are set to very close to the same input voltage. That fuzziness on the input voltage waveform could be just a bit of noise coming from the power supply, and the noise doesn't show when using the super cap because the power supply is disconnected and switched off. Not sure though. I can't really explain yet why the current draw drops so much when using the super cap when it is set to the same voltage, while the output power consumption of the LED remains pretty close in both arrangements. Whatever the reason, it does seem to boost efficiency. In this last test run I left the super cap charging longer before starting the test so that the super cap voltage would be very close to what I had the power supply voltage to.

[profitis]

@tinselkoala ok can you do us both a favour and chop one of your old tantalums in half with a plyers, half between the 2 prongs,vertical not parallel,so that the black manganese dioxide layer and grey tantalum layer is clearly visible,i will tell you what to do next.

[TinselKoala]

@tinselkoala ok can you do us both a favour and chop one of your old tantalums in half with a plyers, half between the 2 prongs,vertical not parallel,so that the black manganese dioxide layer and grey tantalum layer is clearly visible,i will tell you what to do next.

Ah.... no.
The last time I got into one of these "I'll tell you what to do next" things I wound up opening a portal into a dark universe of demons and djinn and it took weeks to close it again. Forget about it.
You tell me the whole thing up front, and I'll be the one to decide whether or not I take that next step.

[profitis]

@tk well if you touch one prickprong lead of your microampmeter to the black half(+) and the other to the grey area(-) you should register a continuous non-stop current.i did this years ago but didnt think anything of it then but now i want to try it again but ive got no tantalums at hand.i just want to know if you get same result and it wasnt an error on my part.the current was much larger with the sliced cap than the closed cap(which just showed capacitance current as opposed to continuous current)

[TinselKoala]

I am not sure what you mean about the resistor in series with the super cap, as this one ohm series resistor is exactly the same when using the regulated power supply, and both setups are set to very close to the same input voltage. That fuzziness on the input voltage waveform could be just a bit of noise coming from the power supply, and the noise doesn't show when using the super cap because the power supply is disconnected and switched off. Not sure though. I can't really explain yet why the current draw drops so much when using the super cap when it is set to the same voltage, while the output power consumption of the LED remains pretty close in both arrangements. Whatever the reason, it does seem to boost efficiency. In this last test run I left the super cap charging longer before starting the test so that the super cap voltage would be very close to what I had the power supply voltage to.

I think the cap and the PSU probably differ in "output impedance". I think this means that, for a given changing load, there will be a difference in the _current_ that the two methods will supply as the load changes. Clearly the JT is a changing load, both per-cycle and over longer time periods, and the capacitor is a supply that doesn't replenish itself. But the PSU is a "replenishing" supply. When you power from the PSU you are essentially powering from its filter capacitors, which are being kept "refilled" by the voltage regulator stage behind them.
I think the PSU probably has higher output impedance than the capacitor, but I don't know, and as I said I don't know how one would go about equating the output impedances of the two, but I am sure about this: impedance matching has a lot to do with power transfer efficiency and if there is a large mismatch between the supply and the load the transfer will be poor.