Joule Thief

[crowclaw]

@ Freepow
Bill has answered your question very well. One point, I assume these output voltages are measured unloaded. As you can see the circuit impedance or DC resistance  increases as you add more turns, the switching current decreases and the voltage rises. An affect on the frequency also takes place. You don't necessary need more voltage if your intention is to illuminate just one LED, but as Bill has mention you can gain more light to energy by using a combination. All LED's have a safe limit to their maximum operating currents which can vary from around 20Ma upwards depending on type. Should you go beyond this limit they start to run hot and quickly burn out. The JT circuit gives a series of high energy short duration voltage pulses, but because the current is being pulsed and not a steady state continuous dc voltage as you would see from a battery cell, the LED will appear very bright but with a lower risk of damage due to the off/on state of the driving voltage. You can add more LED's in series without increasing the current draw depending on your available voltage on load. Any combinations in parallel will not affect the voltage but will increase the current.  M

[innovation_station]

i will apoligize to the long standing hard working members of this site ... 

you know who you are ..  t5he ones that MADE IT WHAT IT IS .. 
and new commers like kooler and others that expairment !  to yous is where my apoligy is dirrected ...

the usual   ones that come in thinking ..  THEY KNOW ALL ..  get no apolgies... they can cry CUZ THEY LOST THERE BALLONS!

what ever

to the people who choose to let it rip then let it rip!
many more discoveries do lay ahead !

if i could finally get my materials ....... GADGET!   

i could build even more things and share them as i always have!

william

i hate to destory an old project as i run out of materials but this happins from time  to time ... : ( 

o well

[crowclaw]

Here we go again! yet another scurmish brewing up... WE DON'T WANT TO KNOW about your differences, this is not the place for off topic rubbish like this.
I'm a new member and joined because  I have a keen interest in the sites topics, and as an electronics engineer / designer I can offer the benefit of my experience as and when I am able to do so.
If you can't make a serious contrubution to benefit the topic then keep away PLEASE.

[Mk1]

@ist

Be the bigger man , chose withdraw , you are on quick sand , buddy ...

Why would it mater what others think...

We worked hard so that we get a nice forum where everyone can help .

Don't bring the circus over here , dumb dumb.

I consider this subject closed. 

[Pirate88179]

The subject is closed.  We do NOT do this here.

Thank you.

Bill