Big Joule Theif

[Tectalabyss]

Thanks for the reply

i was reading the forest mims engineers book from the shack today and ran across a bunch of optoelectric circuits were real simple for a night light circuit I would post the circuit but I havent figured out how to do the url string for an upload yet.....
can anyone explain how to wind a toroid for these circuits? I have a ten mm toroid from a power plug transformer board and tried a 14/85 wind and it doesnt seem to work for the RLC not sure where I went wrong on that...

Hi Area.
Thanks for the reply I was wondering how much more of a draw this would be on the JT circuit Has far has the winding read back a few pages there is a lot of very good info posted on winding.I've used everything from bead type to the round type with good results.I've even heard of winding the coil around old nails and it worked. Thanks Tec

[area46241]

Thanks Tectalabyss- windings...

my electronics hobby is in full swing again thanks to this forum and the youtube...you all have put on quite a show and I feel blessed to have been allowed to be part of what I consider something that could have a positive impact on everyone...
currently I am waiting for a chance to go to the shack for a neon as I have put the imhotep bedini fan circuit together...very excited about that...
...and I have rewound my ten mil toriod according to the makezine video thanks for the advice jeanna and someones photo of the correct joule thief with three different inductor types and still thinking about the connections to the coil and transistor so back to the schematics for some pondering...
Today's question is this the right hand rule...does this affect a toriods performance by any detectable amount as I realized that I wound my toroid with 20 turns of a twisted pair to the opposite of the rule...

[jeanna]

rules

....
..... photo of the correct joule thief with three different inductor types and still thinking about the connections to the coil and transistor so back to the schematics for some pondering...


Today's question is this the right hand rule...does this affect a toriods performance by any detectable amount as I realized that I wound my toroid with 20 turns of a twisted pair to the opposite of the rule...

Mostly I wind according to the easiest way for my hands, but the thing about the center tapped primary is that it is being fed in the center of the wires and while the wires go the same direction, the voltage comes in and splits direction.
I think spatially, and this is tricky for me, but I am quite sure this is the cause of the magic of the jt.

So, to review for anyone:

The center tap is where you connect the pos of the battery
the Emitter is where you connect the neg of the battery
the 2 remaining wires can connect to either the
Base through the resistor, or the
Collector
Many of us who worked on this realized that to use fewer turns on the base improves the performance, but for the first 2 or 3, make the makezine way then move on.

and smile

jeanna

[mk1]

@all

Here is my latest joule thief coil , lighting a filament bulb on the secondary .

YouTube - mk1 TPJT (joule thief) Filament bulb (size49)

Thank

Mark

[CosmicFarmer]

More tinkerings...

I decided to doodle in my workshop, was going to make someone a nightlight but of course I had to obsess over the inductor ;-)

I decided to compare scramble style vs conventional.

For those of you who don't know, scramble style is as haphazard as possible, very unsightly, Doing so removes some capacitance. Conventional is much neater and can cram more wire on the toroid.

So, I wound both toroids with 3/9 wraps for primary oscillator and put 40 wraps on the secondary, one was scrambled and one was normal.

I used a bridge rectifier from radio shack and I know it was not as best as possible but I used the same rectifier for both to keep things scientific

Source was 2.2v
Scramble style got me 12 volts, and conventional got me 9. about .25 to .3 volts per turn. Not bad I guess..... Initially, conventional style got me only 5 volts, but then I squished the primary winds together more, and got a little more out.

Inter wind capacitance/position is important.

but then I tried another toroid I had wound previously and not tested. This toroid I found in a kicked-in broken up television that was rained on for 2 weeks in someones back yard. I had put 15/15 wraps "Makezine" style bifilar for the primary and 60 conventional wraps with a smaller ga. wire as the secondary.

The thing screamed at me and put out 40 volts.

Highest peak resonant with 21 ohms.
So now I doubt my purchased toroids

Toroid Specs: * 55 u * 1.57" OD x 0.95" ID x 0.57" high * Al of 73 nH/Turn-Squared



So maybe a higher permeability is needed.

Tomorrow I will see if I can wind the exact same 15/15/60 style on the cores that I bought and see the difference between the found core and bought core.

The difference that I think will matter is the wires position. Instead of having A side and B side separate, to have both together might be stronger, but that's just a postulation.

When you see "Toroids for flyback / HV Balun" they might be for choking it, not making more flyback.

[jeanna]

choke cough choke cough

55u is a choke.
I got burned 35 bucks last year on some chokes. You need 40 turn primaries and even then you need more for the secondary.

The permeability should be 8.000u - 11,000u or higher.

If you are going to make a jt gift I suggest you get a 10w cfl from the store or garbage. Then you can make a "world light" with the tiny toroid inside.
It is the new kind of cfl that has the toroids. The older ones had some radioactive stuff like old fashioned ballasts in them. Now they have toroids and sing.
They also get hot and burn out very soon so there may be some around in the trash.

Did those chokes come from the goldmine grab bag?

I am sorry to hear this.

jeanna

[serfer5]

winding

Hi All
This is my first post, I have been just taking in all the great info and the last few weeks. I tell you its nice to be around a group that actualy does the hands on work and experimentation, hats off to all of you.

I just wanted to put in my two cents worth about toroid winding. I used the toroid from the cfl as Jeanna suggested for the basic joul thief. I wound with 24 gauge aluminum magnet wire tightly all the way around leaving two wires at one end of the toroid , then on the opposite end I wound all the way around again, this second winding was used for the base trigger. works great with about 24 volts from the collector. Works great.

has any one tried a one wire transmission with the JT, I had 6 leds lighting off the collector through an av plug like in the SEC project

[CosmicFarmer]

Ya Lidmotor had full wireless from a JT style setup, if I remember correctly. Might not have been full scalar cohesion, but the DrStiffler tower turned on.

It seems I am walking in your footsteps Jeanna, making the mistakes you made all over again. I just had my numbers backwards when the wallet was out, I thought a low u was desired. So I chose the lowest. Actually they came from Ebay and I saw the words "For flyback" so I thought that people would make flyback transformers out of them.

I'm trying to rationalize my work and expense on the chokes but its all about having the right tool for the right job. Atleast they have plenty of room and I can put the hundreds of wraps on it that it needs

Its just another learning experiment for me I suppose and hopefully someone can learn from OUR less-successes... I dont want to call them failures because I have one choke all wrapped up that can deliver over 200 volts from a dead AA, so I think that is still a success, but if that wrapping was on a different core I might have real fireworks.

The only problem with the CFL toroids is they are TINY... I had cheerios for breakfast that are larger.

Anyway, my discovery for today is my (choke) that I wrapped multiple styles. First test was 3/9/40 and I got about 13 volts, then I increased the primary to 10/10, twisted together, and left the 40 on there and got 23 volts. Removed the primary and rewound them separate (not twisted), and got 27 volts.

I was unable to get scramble wound to show higher voltage today.
Cheers

[mk1]

@all

NEW MOVIE Slim Version 5 turn 16 layer

YouTube - Mk1 Slim TPJT test

Lighting leds on the satellite coil , and the 2 volt bulb on the secondary .

8 turn secondary about 10 v rectified dc .

[kooler]

hey
this is my backwards joule thief 1.2 vdc 1.5 ma's
small video.. sorry i didn't know i said a cuss word till i already uploaded it..
i'm not a bad person..
YouTube - backwards joule thief

i'll post a schematic if you are interested

robbie

[SkyWatcher]

Hi kooler, what material is your toroid made of and are you sure the amp meter is accurate and can you compare a normal powered fully lit led with the ones you show in video, thanks.
peace love light
Tyson

[kooler]

Hi kooler, what material is your toroid made of and are you sure the amp meter is accurate and can you compare a normal powered fully lit led with the ones you show in video, thanks.
peace love light
Tyson

hey
the meter is accurate.. it blew me away that it even worked for 8$
but my fluke meter from mactools reads the same..
i didn't compare to a normal brightness led.. and at 5ma they are to bright
but at 1.3-1.7 ma's they are hard to look at..
the 1'' toroid is the 5 for 1$ from goldmine..

robbie

[SkyWatcher]

Hi kooler, thanks for the info. The ferrite definitely does the trick. I'm testing a 2-3/4"L X 3/4"dia. ferrite cylinder with 18 gauge bifilar and it stays cold, whereas the previous coil/core using laminated electrical steel was warm. The ferrite gives nice eff./performance with these high frequency self oscillators. I'll have to get a hold of some more ferrite and try that circuit. thanks.
peace love light
Tyson

[mk1]

@Kooler

Nice circuit ! keep the good work!

@all

I just finish a new video showing my last JT construction , but also the bulb lighting from the battery the E-C connection and the 3 different secondaries .

The E-C on this one is really strong , but this design is flawed , with parallel layers the load is transparent but not on this one ...

Its a good one anyway.

YouTube - MK1 Micro TP Joule Thief

The best is still to come !

Mark

[kooler]

backwards jt

hey guys
this is a update on my backwards joule theif.. inductor installed..
found that even since the transistor is backwards it still has bemf in the same direction..
use the secondary for leds..
check volts on battery after hours of running..