Big Joule Theif

[SkyWatcher]

Hi folks, ok the aircore isnt working so great at 1.2volt input, so im looking at the guts taken from a few cfl's, problem is there were no toroids in them, just little transformers that look like they may be ferrite, the metal is black in color. if they are ferrite has anyone tried those, not sure how id wire a bifilar on there though, any help appreciated.
peace love light
Tyson

[Bob Smith]

Hi folks, ok the aircore isnt working so great at 1.2volt input, so im looking at the guts taken from a few cfl's, problem is there were no toroids in them, just little transformers that look like they may be ferrite, the metal is black in color. if they are ferrite has anyone tried those, not sure how id wire a bifilar on there though, any help appreciated.

Tyson, you can also salvage toroids from burnt out computer power supplies. They're often thrown out when the caps inside blow, but there are a bunch of toroids, resistors, etc. If you know anyone at a college or school board IT department, or someone who owns a computer shop, faulty power supplies are continually thrown out there - a good place to ask.

I don't know if these toroids are useable (solid or powdered ferrite?) - perhaps someone else can verify.
Bob

[kooler]

toroids

hello
the pc power supply has mostly powder iron the big ones are like mag amps
but if you get a psu with toroids that have white plastic covers on them and are bifiliar wound.. those are real good ferrite toroids..+ you can use the soft copper wire that is on them or you can strip the plastic off to get a better windings on it..
psu's are still a great source to get transistors , scr's, mosfets , schottky diodes
and heatsinks.., there is always a good size bridge rectifier in it too..

and if you don't mind desoldering go for it..
most pc shops will give you a box full of them.. free
the newer the psu the more ferrite in them..
hope this helps

robbie

[area46241]

electro/magnetic...

Hey there skywatcher I would like to say that the core needs to be magnetic if you want to tranfer the primary energy into magnetic flux then the flux tranfers back into the secondary coil all at the same time. Now I have been wondering if a coil of any efficiency could be constructed by creating an open air coil with another coil wraped around the first all taped or paper wrapped. Has anyone here ever wound such a coil?

[jeanna]

cores or no cores

@Hi area:
There are lots of folks making a special very interesting core over a paper tube (duct tape tube) and getting interesting results.
I have no experience with this but one of them (MK1) found that while the meter pronounced zero for output, he was able to light a white led and an unconnected red led , so, it looks like a great direction to me.

@Skywatcher,
So Tyson,
How many turns of primary are making the basic jt turn on the led in the C-E spot?
That is the first question I want to ask.
The lower the permeability the higher the flux and the more turns are needed to make the toroid oscillate.

btw, the cfl I used was a GE energysmart one. This is the new cheap kind that gets hot.

jeanna

edit
Skywatcher,
I missed a couple of posts and I want to ask you if you are using a dmm for your voltage results?

A dmm simply cannot see the volts. In fact if this is 8v shown from a dmm, watch out!! You probably have 80-150v
You will see the leds shine very bright for one moment then go out.
We were all puzzled about this when we first were doing this because nobody had a scope.

If these volts are coming from a scope, what is the frequency?

[SkyWatcher]

Hi folks, thanks for replies to my posts. jeanna the toroid i have is an iron powder one from a computer psu, so results aren't very good, but it has a total of 36 turns for bifilar meaning 18 for primary and 18 for feedback and pickup(secondary) has 80 turns using 24 gauge for all coils. I haven't checked to see how many turns light a single led but it does as is and i am using a dmm. I wonder if any other material can replicate what ferrite can do thats readily available and cheap aside from figuring out an aircore design that performs as well. I had an idea for an aircore setup that starts with pickup windings on a cardboard tube or whatever then over that the primary bifilar then over that more pickup windings, this way we can capture all the flux, i think. Though using a ferro type core may gate extra energy that pure copper coils may not be able to.
peace love light
Tyson

[jeanna]

Hi folks, thanks for replies to my posts. jeanna the toroid i have is an iron powder one from a computer psu, so results aren't very good, but it has a total of 36 turns for bifilar meaning 18 for primary and 18 for feedback and pickup(secondary) has 80 turns using 24 gauge for all coils. I haven't checked to see how many turns light a single led but it does as is and i am using a dmm. I wonder if any other material can replicate what ferrite can do thats readily available and cheap aside from figuring out an aircore design that performs as well. I had an idea for an aircore setup that starts with pickup windings on a cardboard tube or whatever then over that the primary bifilar then over that more pickup windings, this way we can capture all the flux, i think. Though using a ferro type core may gate extra energy that pure copper coils may not be able to.
peace love light
Tyson

Hi Tyson,
OK good.
The jt you made with this unknown toroid is turning on the transistor. (the light is on)
That is the first thing to check.
The dmm, as I said, is not capable of measuring the volts.
To get the accurate measurement, you must remove the led from the C-E, and use a scope.
If you do not have a scope, here is what you must do to determine the volts:
(I hated doing this enough to make me spend $189 for a hand held scope.)

Put the 2 secondary leads into the ~ sides of a full wave bridge rectifier (fwbr) now, you must extend this and add 2 more diodes to help the fwbr do its job, so put one more on the + and - ends of the bridge keeping the polarity the same.
Get one of those high voltage caps from a camera or another can type cap you have that has high voltage, and put it into the ends of the diodes of the extended fwbr, again observing the polarity.
Give it maybe 20-30 seconds and then using your dmm on HVdc measure the voltage you collected.
I am sure you will be surprised.

OK?

yes, you can do this with air core but you need 600-1000 turns to get the same thing as 60.
the ferrite is amazing and even a powered one works fine as I saw when I used the tiny orange one.
What does not work fine is a choke. (You do not usually know what you have.)
Most of the ferrite toroids are less than 50 cents. I call that cheap enough.

Availability is less good, but that is because they are used to remove the spikes from circuits, so they are in OEM products and not so available on the consumer level. That was the reason for the tiny orange experiment. (10w GE "energy smart")
Bye the way, that light is great.
It is bright and the battery lasts a long while as it should.

-----
@All,
I was watching a video today and realized that at 9v a 10mA draw is a very different amount of draw than at 1.2v so, do not confuse them.
For instance at 9 volts battery a 10 mA draw is 90mW
the same 90mW looks like 75mA when using a 1.2v battery.

Apples and apples

jeanna

[SkyWatcher]

Hi jeanna, thanks for that info. I'm not going to pursue this iron powder toroid anymore until i can get my hands on a ferrite one, i'm more interested in powering a flouro lamp, so i'd need a larger one that the orange size. Right now i'm winding the aircore idea with 100's of turns of 30 gauge for first pickup layers then 24 gauge bifilar then 100's more for pickup layers over primary. will see how it works. Thanks.
peace love light
Tyson

[SkyWatcher]

Hi folks, ok the aircore isn't going so well for me. So i have been digging around and found a couple of inductors from some old speakers cross over networks, the cores do not appear to retain any magnetic field, so i am assuming they are ferrite of the silver/gray color variety, they're 1 1/4" X 3/4" cylinders, i have 2 so maybe ill glue them together and make a flouro driver with it. i'm going to put a central bifilar coil with pickup coils on each side. Also, i remember someone mentioning rusty nails, does the rust give similar attributes as ferrite. Any help is greatly appreciated. My goal is like jeanna's, a good performance low volt input, light driver. Thanks.
peace love light
Tyson

[jeanna]

rust

From many years ago memory
rust is
Fe3O4

Bill who knows tells us that ferrite is
Fe2O3

jeanna

[SkyWatcher]

Hi folks, thanks for that info jeanna. So it looks like common rust is (magnetite) which is what Bill Muller used. And magnetite (iron oxide) can be converted into ferrite. I recall that a chemical that is used for cars to neutralize rust, turns the rust (iron oxide) into a black color substance which may be ferrite in nature. And may be useful to make homemade high frequency cores. Let me know what you folks think. Also i glued my silver/gray ferrite cores together with end caps and will be winding coils next, will see how it works.
peace love light
Tyson

[kooler]

6 volt fun

sorry guys but i couldn't find a high voltage section..
but since this is the second stage that once was on my joule theif.. i will post it here.. the mod can move it if needed

the first video is a bulb lite.. nothing kool but it is lite bright enough..

YouTube - 4 watt bulb on 6 volts

the second video is just high voltage.. sparks and stuff..

YouTube - koolerization's Channel

but thats it for now..
keep it safe
and be warned...... high voltage

robbie

[SkyWatcher]

Hi folks, I put together the silver ferrite core/coil setup. i decided to just wrap it fully from end to end and started with 18 gauge with 5 layers bifilar wound and tested across c/e and bedini flyback mode. Bedini mode lit a single led a little better at around 45mw @ 1.2volt input. The silver ferrite core seems to be more efficient than previous coil/core of about 1/4 the size with laminated core. Next i'll be wrapping the primary with a 30 gauge pickup coil for flouro light. It does seem that the more core material and coil used, that efficiency increases. And of course resonance between coil and core and coil to coil.
peace love light
Tyson

[Tectalabyss]

Led Night light with JT

Hello Everyone.
I've been working with a circuit board from a 120 volt ac night light so-far I've gotten it to run 15 leds.The thing I am after is the fact it shuts down when its daylight. I am trying to get that part of the circuit board to work with a 1.5 volt aa battery The results look promising Tec

[area46241]

night lite 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...