Big Joule Theif

[pentiger]

Hello, I hope that someone can confirm this.

With the Big Joule thief when I try to power an unmodified LED bulb or a CFL the battery(ies) drain within couple minutes.

It's not usable.

I did a Jeanna's Light type setup and with a 108 LEDs bulb my 6v rechargeable lasted 10 minutes. I saw how tenths of volts were going down every second.

Also even without load on the secondary it was going down fast.

I did a small JT with a small toroid before that lit 36 leds and it worked good.

The big toroid seems to drain battery very fast.

Any thoughts are welcomed.

pentiger

[Vaporizer]

Hi pentiger.

This is my 1st post on the forum after a month of reading, saving data, pics, videos and building a few JT's & Bedini circuits. I have a fairly diverse background and may be able to help you trouble shoot your problem. I don't want to come across as a "know it all" by any means. This area intrigues me as the 1st time I read abt it and I'm highly reluctant to accept "never", impossible", or "can't as an answer. I do wish the forum had a "Welcome" area to cover introductions for new members. To all that have experimented, posted, I cannot name all of you or thank you enough for sharing. Failed tests show as much as successful ones IMHO. I just hope to add what I can and help where I can. I love the "open source" concept.

Watching 6v tick down as seconds go by is not acceptable especially running down in 10 min. I didnt see your circuit posted so lets approach this from a strictly diagnostic/elimination of the high drain.
You disconnected the secondary and it had no effect. Actually, it shouldn't as its working on the collapsed field of the primary. Unless you are trying to feedback as in recharging. This leaves 2 possibilities from what I see.
Your circuit is drawing a tremendous amount of current or the battery cannot supply the current needed. What is your 6v source? 4AA's, a 6v lantern battery? Rechargeables? One failing battery in a string can cause the effect you are seeing. As it dies off it cannot conduct the voltage from the others. When it fails I'd measure each individual cell to see if one is greatly lower than the others. You don't mention an Amp rating for the 6v. A 9v rectangular rechargeable is abt 200ma....it would fall off fast compared to 4AA's rated at 2800ma.

You also need to check the current draw of the running circuit. It must be oscillating if the secondary has output. An apparent high current draw as you describe should produce heat somewhere(assuming the batteries have the current capability). The transistor or the coil would be the 2 highest suspects. If you are using a diode in the circuit, it may be in backwards allowing current to flow to ground, but the circuit still operates.
If you have a meter capable of reading voltage, you can disconnect the + lead to the circuit and put a 1ohm resistor from the battery + to the + input of the circuit. Set the meter to read low volts, start the circuit and take a reading across the 1ohm resistor. The reading in volts is the equivalent of the current draw in ma's. So, if you are reading .750vdc, that's 750ma current draw with the JT basically idling.

If you could do these tests, post the results, helping would be easier. Also a schematic of what you are building and a pic of the project will add in solving the mystery.

Hope this helps you.

V

Experience is what you get when you didn't get what you wanted.

[NickZ]

@ Pentiger:
Can you let us know where you got the 3 inch toroid, (if that was the correct size)?
It think that the reason you are draining the battery too quickly is because you are using an unmodified CFL, and/or 120 volt Led Ac. bulbs. You have to gutt the CFL, and the 110v Led needs to be connected direct to the bulb, and not through the rest of the components that are inside.
I just finished wiring a one inch toroid, as Slayer's video suggested, with a secondary, and was finally able to get my anolog volt meter to get off its ass, and show some voltage. Finally... It was like an emocional orgasm for me, or something like that. Plus, I can now light my 50 Led Christmas Tree Lights Set, on a single dead AA. The system stays totally cool, and no noise is heard. I could not light a gutted CFL with it yet, as the coil probably needs more turns on the secondary. I only did about 250 turns, and ran out of space. In anycase I don't know if there has been anyone able to light a CFL off of a one inch toroid, don't think so... Sure works good for everything else though...
Now I am beginning see some of the magical effects that the secondary circuits on the Jt can produce. It was pretty frustrating at first having no induction at all. The secondary circuit produces radiant pulses at much higher voltage, but without the dangerous electrifing shocks, at least not yet.
Anyways, Pentiger good luck with that big coil, and keep us informed as to how it goes with that.
NickZ

[pentiger]

Hello Vaporize and NicZ,

Thank you for all the good info. I re-winded the primary with thinner wire. Now I have less volts on the secondary but it works a little better in terms of the voltage going down. I am not lighting an unmodified CFL only unmodified LED bulb as Jeanna has mentioned. The toroid is one from ebay

FERRITKERN (Ringkern), FERRITE CORE (Ringcore) 78x58x20 - eBay (item 170509165013 end time Dec-02-10 02:21:36 PST)


I made a short video of the problem.

YouTube - Big Joule Thief

I replaced the rechargeable 6v with 4D cells. One or two batteries doesn't give me enough volts to light the bulb.

The resistor in the base is 500ohm, 1K was to big and light wasn't bright even with 6v input.

I would really like to have this bulb working.

Thanks again and hopefully you can give me some ideas on how to improve it.

pentiger

[NickZ]

@Pentiger
I watched your video, nice looking coil.
I think that you need to make the big coil work using only one AA battery first, and see if it will light the regular leds. Once you can do that ok, then see what else it can do. You shouldn't need all those batteries (6v) to light your 110 Led lights. I am lighting a 50 Led Christmas Lights Set, off of one dead AA. It would probably would light 100 leds or more with one dead battery, when using a one inch coil.
The Ac Led bulbs require much more Current than you are giving it with the Jt. Try to connect direct to the bulbs bypassing the components that are inside. I have a couple of AC 16 Led bulb emergency back-up lights, that use a run capacitor inside instead of a battery. Those bulbs will not light from my Jts, unless I connect direct to the bulb.
NZ

[Tectalabyss]

Wellcome

Hi pentiger.

This is my 1st post on the forum after a month of reading, saving data, pics, videos and building a few JT's & Bedini circuits. I have a fairly diverse background and may be able to help you trouble shoot your problem. I don't want to come across as a "know it all" by any means. This area intrigues me as the 1st time I read abt it and I'm highly reluctant to accept "never", impossible", or "can't as an answer. I do wish the forum had a "Welcome" area to cover introductions for new members. To all that have experimented, posted, I cannot name all of you or thank you enough for sharing. Failed tests show as much as successful ones IMHO. I just hope to add what I can and help where I can. I love the "open source" concept.

Watching 6v tick down as seconds go by is not acceptable especially running down in 10 min. I didnt see your circuit posted so lets approach this from a strictly diagnostic/elimination of the high drain.
You disconnected the secondary and it had no effect. Actually, it shouldn't as its working on the collapsed field of the primary. Unless you are trying to feedback as in recharging. This leaves 2 possibilities from what I see.
Your circuit is drawing a tremendous amount of current or the battery cannot supply the current needed. What is your 6v source? 4AA's, a 6v lantern battery? Rechargeables? One failing battery in a string can cause the effect you are seeing. As it dies off it cannot conduct the voltage from the others. When it fails I'd measure each individual cell to see if one is greatly lower than the others. You don't mention an Amp rating for the 6v. A 9v rectangular rechargeable is abt 200ma....it would fall off fast compared to 4AA's rated at 2800ma.

You also need to check the current draw of the running circuit. It must be oscillating if the secondary has output. An apparent high current draw as you describe should produce heat somewhere(assuming the batteries have the current capability). The transistor or the coil would be the 2 highest suspects. If you are using a diode in the circuit, it may be in backwards allowing current to flow to ground, but the circuit still operates.
If you have a meter capable of reading voltage, you can disconnect the + lead to the circuit and put a 1ohm resistor from the battery + to the + input of the circuit. Set the meter to read low volts, start the circuit and take a reading across the 1ohm resistor. The reading in volts is the equivalent of the current draw in ma's. So, if you are reading .750vdc, that's 750ma current draw with the JT basically idling.

If you could do these tests, post the results, helping would be easier. Also a schematic of what you are building and a pic of the project will add in solving the mystery.

Hope this helps you.

V

Experience is what you get when you didn't get what you wanted.

Tec

[Tectalabyss]

Question

Hello All.

I have a small question how long are the run time's with a 1.5 volt AA battery JT setup.I have gotten them to work but never have gotten the run times to more than two weeks and that was with a feedback circuit that didn't work that well. Tec

[pentiger]

Hello All.

I have a small question how long are the run time's with a 1.5 volt AA battery JT setup.I have gotten them to work but never have gotten the run times to more than two weeks and that was with a feedback circuit that didn't work that well. Tec

Two weeks? What load? Mine dies after couple hours.

You are lucky

[SkyWatcher]

Hi folks, Hi pentiger, have you checked amp draw and can you check resistance of your bifilar, it is possible you have a short to core. Other than that, can you post exactly what circuit and parts and specs your using.
peace love light
Tyson

[Vaporizer]

Hi Tectalabyss and thanks for the welcome. 2 weeks? Are you talking abt the LED thats across the E-C junction? On the feedback, are you trying to extend the run time using it? I've read so much I need to go back through my folders I saved and reread a lot. If I remember right, most say you can't refeed the voltage back into the source battery. It just doesn't work. It needs to feed a separate charging battery. I know the Bedini circuit is this way so I may be confusing them.

I have gotten hung up on using the disposable camera circuits I had , which are basically JT's, to run a 9w CFL. A 1.25v AA I can get abt 10hrs from it at maybe 1/4 brightness. I thought it was 1/2 bright but now I dont think so. I upped it to 3v and saw very little diff other than it blew the transistor...
The coil is tiny. It will set inside the center of a goldmine toroid. I changed the transistor to a TIP series and back to 2.5v. It lit much brighter but was getting pretty warm. I looked and the Base resistor was 470ohm. I removed it and put a 1K variable in it. Interesting results. There are 2 settings that give the brightest light. One the transistor stays cool to touch and the other the transistor is hot. On the "cool" setting its still 2x as bright with 2.5v(compared to a single AA) and I'm getting a min of 10hrs on the 9w CFL using 2 AA 1.25v rechargeables. I tried winding a goildmine toroid with a 10:1 ratio and adding it to "kick" the camera coil up. It just doesnt work. I tried isolating it with diodes, caps...nada. Its like the last coil wants to much. If I would wind it with thinner wire so it had more resistance it may work and a smaller core too. The camera output coil is abt 390 ohms.

I have a pic saved I need to find where someone series 2 of them I think. Might try that, or mount it as is and move on. I have 2 3" new toroids I ordered from ebay and 10 2 3/8" that still haven't arrived.

Nick is right. Unless you gut the CFL it will not work. Mine had what looked like a neon in it with a cap.

pentiger, nice vid and that's a lot of light. I cant say if that is normal or not as I'm not quite to that next step yet. You might try the variable base resistor to see if you are using to much to "trip" the transistor. I did read that most use 350-450 turn "pickup" windings. More than that , little increase was noticed.

[Vaporizer]

I apologize for the long posts. I'll try to do better.

I did forget to mention one other strange effect I found. When running on a singe AA 1.25v, I could stand a small medium strength neo magnet on top of the camera coil and I could dim or make it a little brighter than without it by rotating it. My guess is the coil is just below saturation and the magnet, when in the right position, adds a little extra to the cores field that is collapsing with it increasing the output.

This lead me to yet another thought I want to look into. There has to be a formula somewhere for calculating the max saturation mass of a given core size. One that would indicate the gauge wire vs voltage, turns or resistance needed...ect...... I have never seen this posted.

[pentiger]

@vaporizer
Thanks, I wasn't sure if 360 turns is enough. Today I tried changing resistors, ( I need to get myself a rheostat or two) and it's strange - I tested the light with modified CFL and 64 leds and both bulbs need different values. The rheostat would solve the problem of adjusting the circuit for a specific bulb. My goal is to set it up in a box with a regular 110v outlet and a switch so I can connect a night lamp with a modified bulb.

@all
I am using the lidmotor's circuit with 3 and 13 turns on the primary, But I am thinking this my be wrong for this toroid. I will try 5 and 5 and maybe other combinations. If you guys know what influence the number of each turns has on the circuit, please post.

Good luck with you tests.

[SkyWatcher]

Hi folks, Hi pentiger, Ok thanks for the coil turn specs. So as long as there are no short circuits in any of the coils, the fast voltage dip could be because D cell alkalines cannot carry much amp compared to rechargeables. If you look on the web, you'll find with certain amp draw, D cell alkalines will give a drastic reduction in there capacity. That could be part of the reason. Also the JT circuit can heat up the transistor with 2 cells or more, though the heating can be reduced using only the flyback with diode. What this means to me is that even if one adjusts coil resistance and base values the JT circuit does not drive the transistor properly when voltage increases, that's why I mostly use an oscillator similar to bedinis, it's easier to keep heat out of transistor and gives better output.
peace love light
Tyson

[Tectalabyss]

Run time's

Hi Tectalabyss and thanks for the welcome. 2 weeks? Are you talking abt the LED thats across the E-C junction? On the feedback, are you trying to extend the run time using it? I've read so much I need to go back through my folders I saved and reread a lot. If I remember right, most say you can't refeed the voltage back into the source battery. It just doesn't work. It needs to feed a separate charging battery. I know the Bedini circuit is this way so I may be confusing them.

I have gotten hung up on using the disposable camera circuits I had , which are basically JT's, to run a 9w CFL. A 1.25v AA I can get abt 10hrs from it at maybe 1/4 brightness. I thought it was 1/2 bright but now I dont think so. I upped it to 3v and saw very little diff other than it blew the transistor...
The coil is tiny. It will set inside the center of a goldmine toroid. I changed the transistor to a TIP series and back to 2.5v. It lit much brighter but was getting pretty warm. I looked and the Base resistor was 470ohm. I removed it and put a 1K variable in it. Interesting results. There are 2 settings that give the brightest light. One the transistor stays cool to touch and the other the transistor is hot. On the "cool" setting its still 2x as bright with 2.5v(compared to a single AA) and I'm getting a min of 10hrs on the 9w CFL using 2 AA 1.25v rechargeables. I tried winding a goildmine toroid with a 10:1 ratio and adding it to "kick" the camera coil up. It just doesnt work. I tried isolating it with diodes, caps...nada. Its like the last coil wants to much. If I would wind it with thinner wire so it had more resistance it may work and a smaller core too. The camera output coil is abt 390 ohms.

I have a pic saved I need to find where someone series 2 of them I think. Might try that, or mount it as is and move on. I have 2 3" new toroids I ordered from ebay and 10 2 3/8" that still haven't arrived.

Nick is right. Unless you gut the CFL it will not work. Mine had what looked like a neon in it with a cap.

pentiger, nice vid and that's a lot of light. I cant say if that is normal or not as I'm not quite to that next step yet. You might try the variable base resistor to see if you are using to much to "trip" the transistor. I did read that most use 350-450 turn "pickup" windings. More than that , little increase was noticed.

Hello Vaporizer and all.
That's with a small secondary running to a feedback circuit running 10 5mm white leds in parallel across the e c junction by the second week they were getting dim so I didn't post anything about it. Tec

[Vaporizer]

@ Tectalabyss,
I see. That point (E-C) is normally 1 LED or neon to show the oscillator is running, nothing more. Many remove it once a stable secondary load is established to reduce primary current draw from the battery. The paralleled LEDs there are lit by the feedback signal, but are also still on the source battery side using battery current too. Most use a separate winding(pickup) on the toroid to run them. This way all they see is the voltage developed by the collapsing magnetic field of the oscillator, never actually connected to the battery side, and totally isolated.
That should help your time run. Lidmotor has a good example of that with Jennas light vid. He has a 3" toroid running a CFL. The JT is only ringing the toroid, everything else is picked up from the tertiary(3rd) winding. He has room in that vid for many more separate windings too. Its pretty impressive to watch when you think of what its doing. I'll find the link if you need me too.

Edit: Actually, the one LED/neon also protects the transistor from HV spikes till a load is used to do more than just a simple JT circuit. Needed to clarify so ppl didnt start blowing transistors!