# Does any one know how to make an Ne-2 joule thief ??

Recently I’ve been researching on how high voltage joule thief works. The popular high voltage joule thief videos out there are known as Jeanna’s light if I’m not mistaken. I also built my own little LED joule thief circuit, it appear success after all with a 2n3904. But I want to take the concept a little bit further, so I decided to attempt on the high voltage joule thief circuit. It appear no luck, I have 120 turns for high voltage on my ferrite core (1 turn = 1 volt). I know it’s the same principle as the LED joule thief but with the LED removed. I have two 1kohm resistors and I connected them in parallel to get 500ohm resistance. I connected them all like the LED joule thief, but it seems like I did something wrong.  So I ask for further instruction.

Parts that I use:
40 or 30 gauge magnet wire (high voltage windings)
20 gauge magnet wire
2n3904 transistor (Don’t know if that’s the right transistor for this circuit, but it’s for experimental purposes only.)
2x 1Kohm resistors in parallel = 500 Ohm resistance
AA rechargeable battery.
The thick magnet wire are 7 turns.

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electric19813 years ago

use less turns on the primary!! like one bet you will get more volts

steveastrouk4 years ago
Try following this instructable. He recommends 2.4-3V to make it work.

https://www.instructables.com/id/high-voltage-joule-thief/
BlackWolf1024 (author)  steveastrouk4 years ago
I've checked, for some reason I can't get the neon to light. The previous winding in the core gives me out of range of voltage. But now I have 85 turns and did what exactly he did, I gives me around ~11-20 sometimes 16 volts. No F**KING hope, makes me really frustrating. 85 turns HV, 5 Turns on the LV.
4 years ago
More input volts may be needed...
BlackWolf1024 (author)  steveastrouk4 years ago
Are you saying that, 85 turns doesn't meet the high voltage requirements ?
4 years ago
...and another thing.... the induced voltage in the secondary depends on the rate of change of flux in the core. which is affected by the core's properties, and the primary winding. My instructable on flyback transformers, although not directly related to this, may offer some concepts
4 years ago
I'm saying 2 things, 1.) you may well need more turns and 2.) You may need more input volts to kick the thing into life - double up you AA batteries and see what happens.
steveastrouk4 years ago
Have you actually tried measuring the voltage across the neon ?
BlackWolf1024 (author)  steveastrouk4 years ago
I'm getting 0.11 volts DC on the high voltage winding.
4 years ago
Try AC. That's what should be there.....
BlackWolf1024 (author)  steveastrouk4 years ago
On AC I'm Getting 2.1 volt. Can't light up the NEON. But the led have no problem on lighting it up.