Joule Thief

[innovation_station]

Maybe for your caps, but last night after all those cautions, my 1000v dropped to 44v with the diode and cap, but it was OK, and rose back up to 1000v after I removed the diode and cap.

BAAH!
no tape needed, but your caps probably could cause a burn.

The problem with those big caps of yours is that it is not an easy thing to put a cap like that on the shelf along with a lamp.

This is great fun, but not too practical yet.

How small a cap will allow you to light an unmodified cfl?
That is interesting to me, because someone can actually use it and not need the wall power.
See?

thank you,

jeanna

hey ...  i still think you missed it ... 

but whatever! 

those mag smakers ...  ty

w

please re read sparks and wills posts ... 

and MOST CERTIANLY CAUTION TAPE IS A MUST! 

IT WENT ON THE 18 "  RING ... 

what might happen if i fire it 200w rms ...  and flick it then kick it then rize it ..  then ringggg it ?   


piss white lightning .... ?   

you know it ! 

I DIDNT CALL IT THE WSPS 4 NUTTIN! 

: )

H

[innovation_station]

J

THERE CAPS INSIDE THE CFL UNIT ... 
i create a PUSH WITH A JT OR VARIENT...  store it to an approite voltage ...  then it pushes .... 


k


to the caps in the cfl tv invertor WHATEVER......   then   when the caps are FULL   the device operates .... 

till they drain ....  then RE PETE!   : )

AUTOMATIC ... 


im building a unit 4 u

so chill ..  : )

H

this pluggs into your golden cow ...  BACKWARD DRAWKCAB

LOL

NOW DO IT 60 TIMES A SECOND ......  TA DA!

MY MAGIC!

LOL

LOOK  60HZ IMAGINE ...  FROM A AA

[crowclaw]

It actually went really well! I am sending him some coil specs... and he is giving my Unzapped cell to his electrical engineer for further study... He seems to think he will be able to tell me which toroid material will give the best performance. For the time being he is going to get me some toriods based on whatever specs I provide him. Their winding machines are really awesome... I could live in that factory. So much stuff!... He was the one that said why wouldnt you just do that with a transformer, and asked what makes the thief so special... lol
I think within week or so he will give me a coil to my spec and windings to play with... they didnt have ferrite in stock in those sizes... but they had LOTS of ferrite, tape wound, iron and nickel powdered toroids a host of other material which would take a machine to wind...

Cool place for sure!

Thanks
Jason

Hi Jason,

Nothing special or magical about this circuit configuration named as a JT. Sparks has answered the question of it's functionality very well. It's a very simple self oscillating switching circuit. If you look at the secondary winding but replace the transistors collector and emitter with a manual switch and keep operating the switch you will produce an output from the coils stored energy (in very simple terms) the feedback or primary winding negative pulse counteracts the positive bias voltage which normally causes the transistor to remain turned on. The circuit thus self switches at a timing rate as depicted by the component materials making up the circuit. Owing to the simplicity of construction and the added novelty that it works at such a low source voltage has gained popularity amongst experimenters here. So you can see from a simple circuit what else can be achieved by these dedicated experiments.

BTW Amongst the best ferrite toroids I have come across suitable for JT's have been reclaimed from scrap switching power supplies as used on industrial truck chargers or PC power supplies, look for none smooth toroids that have a light grey roughened finish to them. The other tip is to use thin insulated stranded hook up wire. Try and get to grips with how semiconductor devices work and study oscillators... plenty of info available.
Have fun Merv.

[crowclaw]

@ Jeanna

In your quest to charge caps... as already stated please be carefull. The thing to remember here is they instantaneously discharge into low resistance loads i.e. filaments, the current will be high but only for a mere fraction of a second depending on the capacitance value. A CFL may possibly give a flash but require a pulse or sinewave voltage to work. Also take note of the working voltage as marked on the capacitor. Use a series diode anode side to JT and cathode side to + side of capacitor. Include a series resistor if you want to reduce the initial charge surge current. But that's as much as you can do with a single cap as it stands. Merv 

[xee2]

@ jeanna

my 1000v dropped to 44v with the diode and cap, but it was OK, and rose back up to 1000v after I removed the diode and cap.

I would guess that the diode is backwards or your cap is shorting out. You may need to use two diodes in series and two caps in series to handle the high voltage.