Joule Thief

[NickZ]

  Keep in mind when making a ferrite rod to light those led bulbs, that if it has too high an output of voltage, it can burn the electronics circuits that those led bulbs have inside of them, after a while. Especially the little green caps. So, the voltage should not be very high, but the amps can be as high as possible. The ideal is 120v, at the connected bulbs.
  My ferrite bead rod (below) can output about 1500 volts, on 12v single transistor Joule Ringer circuit. And the RF burns are anything but mild.  But, I've burned out the inner circuits on the LED and CFL bulbs, in every case. As I run them, all night long, off of my solar system's battery pack. As well as burning out three multi-meters, already, that I've used to measure the circuits with, and the Exciter circuits, also.
If I lower the voltage, I don't get the same amount of light output. So, it becomes a balancing act.

         NickZ
 

[NickZ]

  As some of us have been hot on the trail of building the Joule Thief, self-runner version, here is the first device that seems to fit the bill.  Or, not?
 
   http://www.youtube.com/watch?v=PoGfSDbnwbk

[crowclaw]

Use a divide by 100 voltage divider to drop the voltage before connecting to scope. You can make one using a 1K and a 100K resistor. Google voltage divider.

Very sensible...connect the 1k as the lower leg of the divider to ground while the 100k becomes the upper leg connecting to the HV side of course. Also use good quality high stability carbon film resistors, just reduces the possibility of arcing or tracking. Personally I would use several resistors in series to make up your 100k value.

Crow

[crowclaw]

  As some of us have been hot on the trail of building the Joule Thief, self-runner version, here is the first device that seems to fit the bill.  Or, not?
 
   http://www.youtube.com/watch?v=PoGfSDbnwbk

Hi NickZ, very interesting, a translation of the replies would be useful. This guy's gone to some trouble to make a PCB so not the usual breadboard hook up. There are two ic's noticeable amongst the components also a rather stiff blue insulated wire crosses the board may be an antenna! May be a receiving circuit together with some clever design  producing just enough voltage to keep going hence the need to excite the circuit with a battery.
That's the only thought I have. I wonder what those chip numbers are?

[crowclaw]

@ NickZ

That looks like a scanning yoke from a TV or monitor you've used for your LED cluster spot, did you add any extra turns or used it as is. I presume it was from an earlier posting way back, if so must have missed it, nice one.