Joule Thief

[Djoko]

Hi all,

I'm using 10 mm ferrite rod with 90 turn primary  920 secondary, BC338 + 3055, 12 V batt and 3 Watt LED bulb. I test it in 2 configuration (SJR 3.0 and JRC/O) by swaping one end of wire of LED to the collector as SJR 3.0 and to the base of small transitor as JRC/O. I found 1 Amp. on the SJR 3.0 config and 350 mA on the JRC/O. There is no change in the LED brightness on the both configuration.

rgd
Djoko

[scratchrobot]

I made the circuit with a normal 220v>12v transformer and was just playing with it, i didn't know my capacitior could make sound 
Without the battery it works very long when touching the -
https://www.youtube.com/watch?v=_H8KCxCj7Do

[gadgetmall]

I made the circuit with a normal 220v>12v transformer and was just playing with it, i didn't know my capacitior could make sound 
Without the battery it works very long when touching the -
https://www.youtube.com/watch?v=_H8KCxCj7Do

Some people just got it . Nice job ! you got it !

My rusty xformer is no where near that .

http://youtu.be/Zz1OkuYdei8

[TinselKoala]

Yes.... there is something very strange going on. This circuit caused me to check the voltage between my good Earth ground and the house wiring. Using the Fluke 83 DMM on AC voltage setting, I get a rock-steady 57.4 VAC between the Earth ground and the ground leads of my test equipment!! There is no "current" available though, it will just barely light a green LED to a slightly visible glow. Scoping the "earth ground" as a signal source I get a beautiful sine wave at 60 Hz, p-p around 150V.
My Earth ground is a 4-foot copper pipe driven into the damp ground underneath a window air conditioner (yes, we still run AC in November in South Texas).
I don't think there's actually a wiring fault in the house, it's been checked several times but I'm going to have to check it again.

The circuit I built, exactly from the diagram, including the bridge, behaves very strangely. I am seeing all the weird effects people have noted above, but I have no HV anywhere. Touching the Earth ground to various places makes the (normal small white single) LED glow brilliantly, and I also get the noises and the phenomenon of the LED glowing dimly or even moderately for a _long_ time when one battery lead is disconnected and fingers placed on the collector or the LED anode or even the "extra" wire for the core.
I get the most interesting results with the core wire connected to the LED anode, then just stroking this with the Earth ground lead to start oscillations, then leaving the Earth ground disconnected.

I've been using 1 to 3 volt batteries and sometimes a 5 volt regulated bench supply.... this latter is _very interesting_ because the LED will glow if I simply hold the output clips in my fingers, both or either one, and touch the usual spots in the circuit... the case of the 2222 is a good spot... while the Earth ground is hooked to the base of the 2222 or to the LED anode.

There is definitely some interaction with the house wiring, through instruments plugged into the line, and even by the body's pickup, and the Earth ground is key to this.

It is very hard to scope this circuit! Hooking the ground probe to the "normal" places kills it, as also reported above. By just randomly probing around I finally got some signals without killing it.... and they are very weird. Like a slow square wave, but on the top of each cycle, a set of 5 or six "spindles". I'll try to get a photo later today.... this thing is really puzzling me.

I am still unsure as to just what circuit is being talked about by most people, though. If you "remove the bridge"... what's left, how is it wired... and how are people getting HV?

My transformer is probably not to spec, I used a TV inductor similar to the one in my NE-2 JT but larger and containing a magnet, that had about 40 turns of heavy wire, and I wound 300 or so turns of #27 on top of that, and covered it with 5-minute epoxy to secure the windings.

[lasersaber]

@TinselKoala


It sounds like you got it!  I have spent all day working and taking power measurements on this little circuit!  I have made some serious progress.  I will post a new video shown showing the complete setup and how to wire it soon.  I will also be posting an updated schematic on LaserHacker forum soon.

There is definitely some interaction with the house wiring, through instruments plugged into the line, and even by the body's pickup, and the Earth ground is key to this.

Today I unplugged the extension cord that runs out to my workshop.  My workshop is about 100' from my house wiring.  I worked all day off the grid in there and saw all the same effects using an antenna connected to my shed roof.  I have no power lines or radio station nearby so this is pretty amazing!