Joule Ringer V4 and practical applications

[plengo]

There are many joule ringers/thiefs in the market and off course I have to start my own thread on the subject.


Following a good conversation with a fella from Youtube (http://www.youtube.com/watch?v=n9h44yOReQA&list=UUxMsLEjmV_Ft0s4RoYJstUg&index=3&feature=plcp) I decided to pursue his designs.


I think this example on the video shows what intuition can do when properly apply. Mind is an incredible device that when we let it do its job, it does wonders.


In this video we have a kind of Joule thief design with a very interesting added second transistor and 2 potentiometer to control the voltage on the base of the transistors, and with that I think there is a unique characteristic that I have not seen in any other device, specially with "Sohei" (if he wants to disclose his name, he is free for that) clever thinking.


I would like to open discussions and experiments towards this variation and possible improvement to power real world lights with very , very little input power.


Fausto.


ps: this V4 is just to show that I seen so far 3 variations of Joule Thief and many forums but I think this one here from Sohei is unique ( I could be wrong - so forgive me for doing that ).

[TinselKoala]

What two transistors?

LM317 is adjustable voltage regulator, apparently fed from the PC power supply. I don't see it, maybe it's in the PC ps box.
L7812CV is fixed 12-volt positive voltage regulator, TO-220 package, on the small heatsink, at the left side of the breadboard near the filter capacitors.

The only transistor I see is the TO-3 device, presumably 2n3055, sticking in the breadboard.

There's another one in the left background tie-wrapped upside down to a heatsink but I don't think that one is connected.

Why he's using 2 voltage regulators at the same voltage, in series... is a little strange. Normally you want to supply a 78-series VR with a little more voltage than its regulated output. If you give a 7812 only 12 volts input, it's not going to regulate very well.

The second potentiometer in the video looks to me like it's just in series with the 7s4p LED bank, or perhaps rigged as potentiometer (across C and E of transistor, with wiper feeding LEDs, other end of LEDs to E of transistor). Is there a complete schematic somewhere I can look at?

I've built a few variants of LaserSaber's circuit myself. My favorite ones light up a small neon on an input of ONE volt from a depleted AAA battery.

[hartiberlin]

Hmm,
in the video he said he put 4 rows in parallel of 7 LEDs in series over the collector-emitter
of the transistor...

So where is the second transistor ?

Any circuit diagramm ?

I just played yeasterday night with a Joule Ringer and Joule Thief to build
myself a low voltage supply for an LED to show my new selfmade battery,,,
but have not yet got to make a new video out of it.

Must still tune it all a bit and look via my scope to it....

But with my more powerful Joule RInger I could light up an 28 Watts 230 Volts halogen bulb
alsready about a quarter  brightness with around 11 Volts and 0.88 amps input.

Have been using some kind of Metglas or iron tape core from an electronic dollar store...

Regards, STefan.

[TinselKoala]

I think there's no second transistor.

The only things on the breadboard are the 7812 regulator (could be mistaken for transistor) and the TO-3 device which is probably a 2n3055. The 7s4p bank of extra LED is, I think, connected between emitter and collector of this transistor. One potentiometer is on the base of this transistor as normal, the other potentiometer is hooked to the bank of extra LEDs, either as a simple variable dropping resisor in series, or as a potentiometer across the C-E, with wiper feeding LEDs at one end and other end of LEDs connected to emitter or circuit ground.

[plengo]

Hey guys,


thanks for shime-ing in.


Sorry, in this video (http://www.youtube.com/watch?v=hvLYr9f9Mfc&list=UUxMsLEjmV_Ft0s4RoYJstUg&index=3&feature=plcp) he does uses 2 transistor which is very unique configuration (at least for me). I will show an schematic as soon as he allows me (I am not sure if it is his design completely or a variation that is already on the forum).


The uniques of the design is very shown on this video where you can see that he is controlling 2 pots to get the flow of energy distributed and at the same time reducing the amount of input power.


140+ LEDs with 12v and 80ma is very unique to me. Specially when the LEDS are fully bright. Don't you think?


Fausto.