Joule Thief 101

[Pirate88179]

Thanks Rusty, I was going to search for your video and post a link, now I don't have to.  I know you explained the circuit much better than I did and I believe I copied your schematic in my vid, ha ha.  My light still works and I use it.  I did remove the VR's as they were not rated for enough power and I burned them out pretty fast.  I think you used a rheostat right?  My pots were only rated at like 1/4 amp.

Bill

[Magluvin]

Have you ever tried the "Jeanna" circuit?  I would have to check my video but I think it was like 400 turns, 13 turns and 4 turns (3 windings) and used a TIP3055 transistor with a 22 ohm resistor.  Outputs about 700 volts.  Lidmotor has a great video on how to make one.


Bill

Hey Bill

Its totally possible that with only 2 individual windings that Im missing out on something.  My last try was with very few turns on the base control winding compared to the secondary drive winding. It just didnt seem to have the range of operation as the 1 to 1, or even not work at all with 1 or 2 turns compared to say 40 on the drive winding. Too little base biasing?  This has been my first experience with this circuit the past week or more it has been. Ive tried a lot of things, some that probably had never been tried before, like using a shorted winding and finding that it can still work well and the freq of operation was raised to very high multiples than without the shorted winding.  That there was a little bit of an eye opener for me in the fact that the shorted winding didnt kill the circuit operation or cause excessive input draw, but nearly the same draw with similar brightness as without the shorted winding. In a normal situation it would be disastrous to have a shorted winding in a transformer. But in the normal situations that we may encounter, say a simple 60hz transformer, dont really have the option of self adjusting freq to the conditions of the circuit. That alone has brought me to a new level of understanding. And I hope it does others. As a shorted winding isnt 'always' a terribly bad thing. In a way, im using it as a freq of operation multiplier, all in hopes of it helping me get the thing into the realm of resonant freq of the transformer.  Havnt been able to get up there without it. I think Im getting close. Seems to be upwards near 2 to 3mhz that I need to be. Next purchase would be a sig gen to identify these resonant freq without all the guess work.

So far Im just fiddling to get used to changing things and getting a deep feel for what does what... and trying some whacky things that may come to mind. Like last night I had 3 leds in 3 different places in the circuit and all three lit of near equal brightness at the same time. Even 2 leds in parallel without resistors on each would light.  Not really the case for 2 leds in direct parallel connection, from what I know. If one conducts first because the other has a very slight difference in conducting range, the other will not. In most all cases i have seen there is either a resistor in series with each led in parallel circuit. But it may be that the input pulse is high enough that the led's leads are enough resistance so each is biased enough to conduct and light up seemingly equal to each other.  I dunno. Maybe Im just a nut bag.
Havnt tried it lately but have in the past where if 2 leds are in parallel, only one would light, the one with the lowest turn on bias ability. Maybe thats just with old stone age leds of my past.

For now Im still playing to get the feel for what changes in the circuit does what. Once I get a real hang of it and know it down pat, then when I want to make changes to the circuit, I can make educated guesses as to what the outcome will be by knowing what affects what in the circuit.


Ok. I feel I am babbling.  Tired. Was up all night, no sleep, working on a sound system in a vw gti. Sometimes I just cant quit. So if anything I just wrote doesnt make sense, or seems nutty, well, then Im just a tired old nut at this moment.

Mags

[sm0ky2]

@ mags

looking forward to your results

I never experimented with anything as low as a 1:1.

I started with 22 windings, which I guess would be an 11:11, considering the center tap?

many replicators carelessly wound these "bifilar",
while I myself preferred to wind them, each wire at a time, in the same fashion.
This decreased the imperfections in the coils that may lead off the "true slope"

greater perfection resulted in a cleaner signal.
once I got the sine as clean as I could, within the primary coil:

all other advancements were done using a secondary winding on top of the JT primary, on the same ferrite torroid.
even my experiments that daisy-chained multiple torroids, were all driven by a secondary in this manner.
the secondary was not electrically connected to the JT, and only driven by the inductive coupling through the ferrite.
The signal on the secondary was usually "cleaner" than the primary, as it was a function of the inductors resonance,
not including the destructive feedback from the primary circuit.

everything I did was built upon this baseline.

It is nice to see someone going beyond that to make it simpler, one to one winding and observe the limitations of induction.

[sm0ky2]

people get lost in a cloud of dreams when they look at a Joule Thief.
it is not magic, it is not overunity
what a "JT" does best, is something of great economic impact, but it has nothing to do with free energy research.
It can be used as a tool for assessing economic value of portable energy.

most people look at it and see something special because ooh wow, a light is working with not enough voltage!
oh my...

lets look at a comparable novelty that toys with current, rather than voltage

a man whos car battery died, he cranked and cranked and it will crank no more...
I walk up with what looks to him to be a "bunch of wires"
and start his car using his "dead" battery.

now, me - understanding that the battery in his car, while charged up around 11-13v can provide several hundred amps of current,
  but when depleted to around 8-9v, it cannot compete with the resistance of the starter circuit, and thus there is not enough current to perform the task.
by lowering the resistance, through multiple paths, I am able to provide enough current to start the engine.

to the man with the broke down car - I did something magical, in starting his engine with a "dead" battery.

all I did was verify Ohm's law.
The Joule Thief is no different.

change battery types and you will find that some batteries have "more energy" available below the 1.0v range, than others.
This can be measured directly, or estimated by "run times" etc.

the "best" batteries are made by Energizer
These provide more available current in the range that most devices operate.
thus, when used in a JT, they have the least available energy for a "dead" battery.
This is important, because we BUY energy based on an economic standard.
even in batteries.

Cheaper batteries that "die" faster in modern devices (despite their MaHr rating),
have more low-voltage current left in them after they are "dead".
Thus, they will work better in Joule Thief applications.

- This is why the same batteries should be used for testing any type of circuit like this.
not only the same type/brand, but similar voltage levels, when testing.

[tinman]

@ mags

looking forward to your results

I never experimented with anything as low as a 1:1.

I started with 22 windings, which I guess would be an 11:11, considering the center tap?

many replicators carelessly wound these "bifilar",
while I myself preferred to wind them, each wire at a time, in the same fashion.
This decreased the imperfections in the coils that may lead off the "true slope"

greater perfection resulted in a cleaner signal.
once I got the sine as clean as I could, within the primary coil:

all other advancements were done using a secondary winding on top of the JT primary, on the same ferrite torroid.
even my experiments that daisy-chained multiple torroids, were all driven by a secondary in this manner.
the secondary was not electrically connected to the JT, and only driven by the inductive coupling through the ferrite.
The signal on the secondary was usually "cleaner" than the primary, as it was a function of the inductors resonance,
not including the destructive feedback from the primary circuit.

everything I did was built upon this baseline.

It is nice to see someone going beyond that to make it simpler, one to one winding and observe the limitations of induction.

1:1 is the turn ratio of the two windings smoky2--not the number of turns.


Brad