Joule Thief

[resonanceman]

Hi all been doing lots of reading about the JT circut....JT 101 mostly trying to digest all the info .....built my 1st .....it didn't work at all...I used a transistor out of an old stereo, as well as the resistor .....my ferrite core is a ring magnet from a speaker..........because core should have high permability........how much higher can you get.....just curious as to what is the best design to date .....an update page every once in a while on the best construct would be a definate asset......no sense in re-inventing the wheel .....I'm on dial-up so it takes forever to load a single page ,worst when their's pics...Q where can I salvage a decent ferrite core?...thanx for any help ....shylo

Shylo

The best JT for one thing probably will not  be the best for another use.
If  you have something in particular you want to do with a JT then maybe someone will be ablwe to help you with a specific design.

About where to salvage a good core for a JT
How much  do you know about electronics and safety with high voltages?
If  you know enough about high voltages to take the proper precocions
you can use the flyback  transformer in old TVs or Monitors
These  make great JTs and there big enough  you can do stuff like light light up a CFL ........ The first time I lit  a CFL it was with a flyback  transformer.
If  you do  not understand the dangers  involved in taking old TVs apart  do not  mess with them without someone to show you how to ground the high voltage  before  you start taking them apart.
The picture tube can hold  a strong enough charge to kill you........they can sometimes hold this charge for years.


gary

[NickZ]

    @ Resonanceman and All:
     Has anyone tried using the big 3" ferrite toroid cores that are found in the back of the crt Tv picture tubes, for use in a Jtc? 
   Suppose that we wanted to be able to light up many Leds.  Lets say, 10 Led bulbs like the -Lights of America- bulbs, that use 30 or more leds in each bulb (or led panel),  for a total of 300 or so, individual leds, with each led being 20mA, 3v.      How would you build a Jtc (high or low voltage), to best accomplish something like that?...   Or, would it be better to use a 12v Jt circuit, with 12v battery, run caps, etz...
I'd like to avoid dangerously high voltage. Prefer cool radiant pulse circuits.
                        NickZ
   

[resonanceman]

    @ Resonanceman and All:
     Has anyone tried using the big 3" ferrite toroid cores that are found in the back of the crt Tv picture tubes, for use in a Jtc? 
   Suppose that we wanted to be able to light up many Leds.  Lets say, 10 Led bulbs like the -Lights of America- bulbs, that use 30 or more leds in each bulb (or led panel),  for a total of 300 or so, individual leds, with each led being 20mA, 3v.      How would you build a Jtc (high or low voltage), to best accomplish something like that?...   Or, would it be better to use a 12v Jt circuit, with 12v battery, run caps, etz...
I'd like to avoid dangerously high voltage. Prefer cool radiant pulse circuits.
                        NickZ

NickZ

I have never  tried the core on the yoke of  TV tube as a JT
I believe IST tried them  .......he suggested that I try them...but I never got  around to it.

I am not sure if they are actrually ferrite.......but it probably doesn't matter. If they are ferrite they will run with less windings.
There is  plenty of room for more windings  if they are iron.

As far as lighting 400 LEDs ..........I assume you mean to full or near full brightness. 
It might  be difficult to do with  just 1.5 V .......  you can light  them pretty well with one battery ......but I think full brightness would be dificult

The  yoke core might be a good  thing to try for this ........a flyback transformer core might work well too.

I know I have never been able to get that  much power out of a single 5 for $1 toroid.........but maybe it can  be done.

Personally  I would use a candy cane coil........ I use them for  most of my experments.
I don't remember anyone else every saying anything about having made one.... but I find them very useful........and  they can be scaled........if  it doesn't  have enough power.........just add more toroids.
I am about out of time tonight. 
I will try to take some time and see what it will do with LEDs
I think I have 400 LED christmas tree lights.....
I will try to post a picture tomorrow evening


gary


As for  12 V
I use  12 V quite a bit.
it is MUCH easier to light a CFL with 12 V than 1.5

[Pirate88179]

Nick:

You can easily light 400 leds from a modified Fuji circuit.  It has been done many times.  Also, this was done with a "dead" AA battery at way less than 1.5 volts.

Bill

[NickZ]

   Guys:
   Thanks for the replies.
   I'll be getting a solar panel and a couple of smaller 12v batteries to work with soon as possible. But the idea is to make a big strong JT-TPU circuit that is feeding back to the run batteries, or run caps, and eventually not needing the battery-solar panel support.  Since once the Jtc drops in its run battery voltage, it is not working properly, if not kept at a constant optimum running frequency. There is no circuit that can work Properly like that, if not kept at a constant input level.
  I have been trying different transistors, resistors, diodes, pots, caps, toroids, Leds, etz... trying to find the winning combination.  It seams like a simple quest, but it's not.
What keeps me hard at it , is the idea that a self running joule thief is more than possible, and that it can be upgraded.
  Otto had said that what makes solid state components interesting is the fact that sometimes they can be fooled...
                                                   NickZ