Joule Thief

[jeanna]

@jesus,
Thanks for that drawing.
It is exactly what I was trying to say.

Thanks both of you's for your help, I tried it and it works 

Is it possible to charge up a HV Cap 400v as fast as a Disposable camera does by only using a Joulethief

On the kapandanze thread, someone just posted a really nice link to the camera circuits.
Probably this is not new, but I understand it better.

Here is the whole page:
http://talkingelectronics.com/projects/XenonFlasher/XenonFlasher.html

and I made a screenshot of the part of that page that is what they called a pump.
I will post it below.

@ A-K
I think I understand, now. Thanks for the explanation.

I started a thread on recharging batteries from a joule thief circuit, and some people shared their results.
I was able to recondition any battery using this secondary with enhanced bridge as jesus' drawing shows.

I also want to add that while the meter will only see a small amount of amps draw, at least half of that draw went missing in many of my jt circuits. I thought there was a problem, because on a 2500maH battery if the drain was 250ma the battery should have lasted 10 hours but was only lasting 5 1/3 hours.
Then when I used the copper-magnesium galvanic battery which has restricted rate but good strong voltage the truth really came out.

So, I am delighted to see more folks working with the magnetic component. It is the magnetic component in the toroid that allows the secondary to freeload so much,  and I also want more.

So, go for it!

jeanna

[nievesoliveras]

Thank you lady @jeanna

@stprue
I think that the thread came out first and @ist did his replication version after he saw it.

Jesus

[stprue]

Thank you lady @jeanna

@stprue
I think that the thread came out first and @ist did his replication version after he saw it.

Jesus

I see, sorry about that!

[resonanceman]

Thanks both of you's for your help, I tried it and it works 

Is it possible to charge up a HV Cap 400v as fast as a Disposable camera does by only using a Joulethief

I tried a small secondary which measured about 100v, and charged a 400v 180uF cap and watched the DMM reading while charging, and it only showed the Cap starting at 40+ volts and going up slowly 

Can I charge it up quick like a Disp-camera ?
What voltage will I need coming out of secondary ??

Freepow


The camera flash units  are optimized for  speed.

There are many ways  you can  speed up  a JT.

Do you use a potentiometer  for the base resistor  on your transistor?
Lowering the  resistance  will allow the JT to use more power.........

Raising  the voltage to the transistor  is also a way to get more power through the circuit.

If you intend to  get  as much  as possible  out of a dying  battery   putting a capacitor across the battery  will  allow the battery to charge the cap at its maximum rate ...then the JT can take what it needs  for each pulse from the cap.

Do  you use a tank circuit?  ( A cap across the base resistor or pot. )
A tank circuit  can cause the circuit  to  go into resonance.......you will know that happens  when  you swing your pot through its range and you get a spike of power through the JT somewhere in the middle of  its range.
I find that  a .1uF cap works  well in  alot of my circuits.
On many of  my circuits  using a large cap  seems to pump more power through the circuits....... often the  output  will blink when using  low power and a high capacitance tank.....  I have a 10uF cap that I often  use for these circuits.

Using  a better transistor  is  also a way to get more power through a circuit........ I use mostly TIP3055s ....... my first large transistor JT used a 2N3055   I went through  quite a few of them.
A TIP3055 is a much tougher transistor......... yesterday I accidentally
connected  12V to a JT  that I had just tested  with a single AA battery ( no extra base resistor ) .......my pot glowed and smoked......but everything still works. From my experience a 2N3055 would have been fried in  milliseconds connected  like that.




Most of  the JTs that I have made lately  are what  I call candy cane coils...... made of many 5 for $1 toroids.
I usually power  them with 12V .......
I bring this up because  another way to increase the power is to make  the coil bigger.
My candy cane  coils were intended  to replace larger and hard  to find  toroids.
I do not think a Jeanna light  can be made  with a small toroid.
I strung a couple candy cane coils  together  to make one big coil with about 40 5 for 1 toroids. ........ powering it with 12 V  it easily lights  a 25W CFL  very brightly.......it reads 250V with the CFL lit up.....over 600V unloaded.
I have still not  been able to reach enough  voltage  with a candy cane  coil to light  a CFL with a single  battery  ..........but I have  not  tried more primary windings yet........ right now  I have 4 laps through  all the  toroids......... that is my normal  proimary.


gary

[freepow]

   Hello Thanks everybody for help, has anyone come accross this.........

     I have a joulethief  with just a small toroid with secondary, and I have an enhanced bridge  on the
     output of the secondary, my DMM reading on this JT was  109.1 volts.

     Then something I tried (which I was told to try) was putting a CAP in parallel with the Base Resistor and
     then I retuned my 1K pot and I now got  110.4 volts.

     Then I tried something more interesting by adding a 5 foot wire antenna to the Collecter of my
     Transistor, and lo and behold I now get  114.1 volts.

     I have not tried a long antenna as yet, but what does everyone think about more volts with an antenna
     ??