Joule Thief

[stprue]

st bro !

that is a wicket video ! 

great work ..  its wonderfull!

perfect timeing unit .. 

: )

W

use another led to fire the fet ..  make 3 of em ...  and change the flash rate ..  2.5 5 7.5 : )

smack a neo !

: )

i have the power ring almost built : )

9 cam boards 3 caps 20000  those fill as many caps as i want to fire from fets .. : ) or relays or pwm's

were GONNA HETERODYNE YET FROM A JT A CAM BOARD AND A FEW FETS MAYBE A COIL ... 

MAYBE NOT ...

: )

Thank you for the kind words IST!  I'm deffintely not done with this circuit but I am putting it on hold for a while! 

[stprue]

hey folks
i got a stupid question..
do any of you know how long a jt runs when it is pulling 104 ma's..
sorry to bother anyone .. i know i need to learn the math
the battery was from my wii and it had 1.2volts left in it..
so i thought at 104ma it should run down quick..
but 24 hours later it still has 0.79 volts and the led is still full brightness.. it's really to bright
i don't know the mah of this battery it is a cheap eastpower from china

thanks

ps.. stprue very nice video.. you have done alot with that circuit..

robbie

Kooler and all we should be doing math when drawing low ma's I have found that my DMM actually reads 0uA on the circuit I posted but after doing a cap test I found it to be drawing 1.5 or so uA.

Kooler use this

http://www.electronics2000.co.uk/calc/capacitor-charge-calculator.php

then follow my math and if you need help just ask   

[stprue]

Actually, this low an amp draw: the supercap would bleed faster than the circuit.

stprue, can you repost or link to a schematic?

I modified Koolers diagram!  Sorry I have no skill or time for the diagram.....I was hoping xee would make one for me hehe

[stprue]

This isn't a stupid question.  Depending upon the 'state' of the source voltage, a joule thief circuit may in fact use more milliamps when it's close to its death. ..the cut on voltage for the transistor has a lot to do with this, but I've noticed on my models that when there's no load on the device, it uses more current than when there is.  So...

Bearing that in mind, it's a good idea to keep a load on ( the secondary ) or off the collector or somewhere in this circuit.

Also, you'll want to keep in mind that batteries have a tendency to regain their charge voltage wise after a sudden discharge, so a joule thief might cut off, then cycle on and off again before it's really 'dead'.

The math is relatively simple, if you have a 2450mAh battery, then you have 2.45 amps or 2450 miliamps at your disposal for one hour.  Batteries, again, can be somewhat deceptive, as it may in fact be capable of supplying 3 or 4 amps over the life of a complete slow drain.

Sticking to the basics:  using 100mA your circuit will run for 24.5 hours it just a matter of turning mAh into mA.

Depending on your configuration, there will come a voltage point that the transistor will stop turning completely on and the current will simple bleed through to ground via the base-emitter path.  This is when the device may consume more milliamps that when it would loaded and the battery will become depleted for the duration of it being connected.

The only way to know is to compare the battery's performance to one which you know the properties of - this would be rather difficult because of the differing properties of manufactured AA cells (or what have you) and the various 'states' the circuit source finds itself in.

Stated perfectly and you are right about the JT using more power toward death.  Usually either the ma draw increases or stays the same but the voltage draw increases...there is a give and take to keep the circuit running.....well most of the time!

[innovation_station]

what have you ever done POSER ?  ... 

TRY TO STEAL MY WORK ? 

COPY A CORE YOU FOUND IN A MICROWAVE ...   

AND CALL IT YOUR OWN ... 

LMFAO... 

FOOL ... 

GO BUILD MY COIL AGIN ....  LOL... 

and then try to tell me it is yours ..  then ill digg up my post from literly years b4 you came around ... fool ...

i guess you didnt know ... 

I BET THE HOLE SITE KNOWS THE TRUTH ....  : )

WHY CAN I SPEAK MY MIND ?

WHY ? 

HOW COME I HAVE NOT BEEN SET TO READ ONLY ...  .. 

SHALL I PUT EDDY THE GOAT BACK IN THE BARN TOO .... ? 

CARE TO JOIN PONY ?

LMFAO

W

and mark if your coil is better than a cam board ...  useing 1 transistor ...  show me ...  : ) 

i want to see a video of your coil  chargeing a large value cap to hundreds of volts .. in less then 20 seconds ...  from a aaa

350vdc 2500 uf..   

and i AINT TALKING A TIP 31 OR A 3055 ...  IM TALKING A TINY NPN TRANSISTOR ... : )

SURE I CAN FILL CAPS FAST TOO IF I USE A TIP OR A 3055 OR OTHERS....  : ) 

WICH I HAVE SPOKEN OF PUBLIC HOW AND WHY THEY WORK MUCH BETTER ... 

AND SLAYER 007 COVERED THIS SO........YOU CANT TRY TO STEAL HIS WORK EATHER ....

btw MARK   you remind me of seymore climeing up in the sick a more tree .. to see what he could see..... 

hummmmmm....

you will LEARN OF MY PALACE  BY RUNNING BACKWARD ...  THIS IS FACT !   in doing so im trying to teach you to walk forward ..   this is why some of my things are revielied ... only to point the way of the truth ..

so the truth is   almost all is forgiven where i come from ...   but NOBODY GOES 15 FOR FREE ...

that means ...  im standing at the door !

: )

just like it allways has been ... 

why all the birds in stone anywhy?

lol