Joule Thief

[Mk1]

@all

I seems we don't need ac for the mag amp ...

this is my conclusion after reading http://www.tpub.com/content/neets/14180/css/14180_140.htm

On the first page , you see a mag amp controller , not a amplifier , all the details are in the following pages they even put a bridge at the input from the ac , it needs rectification ...

So my guess would be pulsed dc should do ...

Mark

[jeanna]

MK1
I am glad to see the pulsed dc is the right thing.
I want to say that my reason to do this is the great possibility that all transistors will soon fail.
I think I am seeing the beginnings of this.
It is pretty sad to see a whole double handful of transistors that are no longer much good just because they were sitting near the window.
eesh.
If the mag amp can start a circuit, then the increase is possible by using inductors to re-pulse the original pulses.
(I do believe stubblefield made a mag amp so we do have some kind of model.)

@Bill,
Let me try to describe the switch problem.
The switch is in the red pos wire of the battery where it normally is in a dc circuit.
The joule thieftoroid and all primary parts are connected to the transistor etc, the jt  secondary is hooked to the pos and neg areas of the unmodified bulb.

So, it turns on and off with the switch.
Except it does not turn off once it has turned on.

The unmodified bulb has capacitors in its circuitry which hold juice even when the switch is off .
As that drains out , which is into the secondary, the secondary stimulates the primary and restarts the primary oscillation.
This then recharges the caps in the bulb.
The thing is the most complete joule thief because it never stops until the battery is at 0.005v!

I did not believe this the first time, but it repeated once with the same original switch, then again yesterday in an entirely different toroid and switch but the same unmodified bulb.
So if the battery wire is moved far enough away that no arcing can happen it should work .

It is a strange problem, and actually could lead to an overunity circuit by someone better than I, but it is very annoying at the moment. 

jeanna

[xee2]

A friend gave me some xenon tubes so I made a video of them using the kooler JT+SCR circuit with 0.5 uF capacitance. This and two more videos using this circuit are posted on YouTube.

http://www.youtube.com/watch?v=viM_vsXVVHk

[kooler]

nice video xee2
3 tubes thats alot of volts
lol.....

[jadaro2600]

I have not built this circuit yet, but I was planning to do it some day. It should work. Make the inductance as large as possible. It is not as simple as a regular JT and will be more picky about component values, but it does not need a toroid.

http://www.overunity.com/index.php?topic=8564.msg218736#msg218736

I thought this was interesting as well, ..this doesn't solve any problems with regard to removing the paths from positive to negative though, ..the original Joule thief was intended to bounce voltage up same as this one.  I think this is a jtc, having a toroid doesn't classify or declassify; just as well, having a secondary may as well be the new standard now days

everyone seems to be working on transformers, this seems as interesting alternative, i've tested the circuit and am reading anomalous activity on the NPN transistor.  I can't get a frequency reading on it, nor can I get an ohmic resistance across its C-E ..when the circuit is on.

I'm using a 2n3904 and a 2n3905 ( to keep things relatively sane )...I'm hoping the material characteristics are identical.

...
I always seem to be going in the opposite direction from the crowd.

While I am dreaming and working on downloading information about how this is done without a transistor, some others are adding transistors.
...
@All, So, why use a second transistor???

Why not expand on the principles that have been shown lately?
For instance,
xee2 had a filament bulb lighting from kooler's circuit.
This is real potential.

Why not follow up on this and take it to higher limits?


BTW
I am coming to the conclusion that switches cannot take the effects of the higher volts.
For the second time and second switch, I have seen that the unmodified led bulb, which keeps the High voltage oscillating after the switch is off, has drained a battery over night to the point of leaking.
It was a cheap chinese AAA so I tossed it and washed the battery holder, but this needs to be solved.
We need a better way to switch the battery on and off.
I think an extension of Bill's idea or some kind of physical removal of the battery wire with easy replacement in the dark is good to work on.

thank you,

jeanna

I've been getting at the voltage oriented angle, so have many others, that is to say.  We should approach this device in a voltage oriented manner, with a little as possible flowing wastefully.

I think we should try using a mosfet or a jfet, and do away with the current flowing from base to emitter - , this may cut 10 to 20% off our current use, ..just as well, the switching and resonance can can be fine tuned without the confusion of whether or not the transistor is all the way on or what.

I think most modal fets will iether be one or off when operating, no partiality, and have high switching mode capabilities, since most of us are working at kHz frequencies, most fets will get the job done.

Personally, i'm looking for one in the off position, and activated by voltage - such as it is, the only thing I have to do is create a voltage difference, and the oscillations ensue.  The voltage oriented gate would allow us to utilize the aspects of the circuit for voltage oriented effects.

As for the winding, i think fewer winding would be needed because greater transient voltages will be present on the secondary..  The coil to base would be minimal, and..

as was asked, with regard to why more than one transistor - it's a matter of creating coherent sine waves which serve to create long lasting voltage oriented florescent light - otherwise the joule thief is just pulsing DC.

When the circuit is operated with minimal coils to base, two fets, and two medium coils to collectors, and one massive secondary, AC will be produced as high voltages, using minimal current, and at resonance with the toroid.

[ there will never not be resonance in these circuits, only an optimum setting for output ] which the circuit doesn't know about - it just goes into resonance.