Joule Thief Charger - Crunching the Numbers 01

[marthale7]

I think to have a fair comparison, I have come to the conclusion that the leds's have to put out the same lumens of light as if they were gettting the standard current.  I have not done the test as of yet, but I do have a lumen meter, was thinking it would be great to compare led's with the recommened wattage, verses the JT input and see how they compare for light output.

[72fr250]

I really don't see the difference between these joule thief charger circuits and the bedini radiant charger circuit to tell you the truth. If you look, the charge battery is hooked up backwards across the coil just like the bedini circuit. It's all the same radiant spikes yeah?

[acmefixer1]

The efficiency is the power output divided by the power input. The Power in is easy, just measure the current and voltage and multiply. The power output gets trickier. If you rectify and filter the pulses to DC and measure the current and voltage, then you have a reasonable value. If you do like I do, just measure the current across a 1 ohm reisstor in series with the LED, and assume 3.2V, then it gives a relative value, but it may not be accurate due to the meter.

[mrBr00k5]

Very nice! Great video!

[bonecrime]

I just want to point out a thing or two. First of all, your joule thief will consume power from the battery in pulses, wich your multimeter most likely can't measure properly. Secondly, how do you know the power going to the LEDs? You don't, because again they're beeing pulsed, and you know neither voltage nor current. Checking the peak voltage with a scope is possible, and also the current if you put the scope across a series resistor. Then you'd have to calculate using duty cycle, etc. :)

[fdoca]

Great Vid,

Well prepared

Hopefully soon you can charge 9v to 12v use a AA , Lidmotor charger did a wonderful job !

[curator23]

good video... except that the dmm screens are unreadable.

yr convnal power calculation doesnt incl loss in current limit resistor.

the inability to charge above drive voltage may be due to the leds damping the output pulse.

what type of diode do you use on the outpt? try a schottky diode, eg BAT85, as these shld alow more of the pulse through (make sure the revrse breakdown is higher than the peak chrge p.d. also, dschrge the chrged bat and measur energy. se hw mny tms u cn rpeat on 1 drv bat.

[kaduisaui]

Excellent video. One of the few vids online where there is understandable narration and detailed descriptions of what is going on. Thank you very much for posting this. Please post more!

[dodoshlodo]

thank you i appreciate the comments.

I have many more videos, check out my channel and subscribe

This is an old video, ive posted like 5 since this one

Here is my latest:

watch?v=bUqrGLrPnso

[tonysam11290]

Hey man, great video, awesome presentation. keep up the good work!

[stevesrd]

very nice,,good work,,been there a few different ways before,,exciting stuff, keep it up, limitless possibilities.

[overunitydotcom]

Good work,

but your LEDs never need 3.2 and 100 mA !

Try to see, what these LEDs use at DC voltage so they have the same brightness..

Probably only need 2.7 Volts and 5 mA for this brightness !

Just compare !

Regards, Stefan.

[dodoshlodo]

Stefan,

they prob dont need 3.2V to light as stated in their specs, and my calculations were not done with 100mA (max rated) they were done with 30mA. to make the same amount of light u need around 30mA conventionally, ive done tests.

They wont work on 5mA

I might do another video set up a conventional circuit and the joule thief circuit next to each other and compare numbers and brightness.

[GBluer]

Excellent Video

Thanks for posting this.

[Lidmotor]

Excellent!! Crunching the numbers and showng them on your computer was great. It is what Mart Hale is doing on full size lead acids using Bedini circuits. On my experiments I have used identical batteries and the charge battery voltage has exceeded the run battery. voltage on all the tests. I swapped batteries once a day on the 1st 10 day run. On this second test with the old alkalines I'm doing it every 12 hours. 10 to 20ma draw is exactlly where you want to be. Good job.

[dodoshlodo]

Lid,

Yes I love Marts work with his Bedini! His experiments are quite thorough. we need to be examining these devices closely I think...

ATM I cant get the charge battery higher than the run mbut I haven't done tests for more than a few hours, still fine tuning the circuit..

U seem to be getting some great results Lidmotor, perhaps you could record some of the "number" of your JT's performance

[boxa888]

nice man, great eqations and scientific work. thats how you shut the skeptics and wackos up! great work!

[Pirate88179]

Great video!! Very well done. Thank you for the credit you gave me.  I appreciate it.

Bill

[dodoshlodo]

No worries Bill, your videos have been very helpfull. Ive just built a bigger Super Thief and hope to get it running 100's of LEDS just like you do

[crob227]

nice work, like the graphs, really shows your taking notes.

[dodoshlodo]

thanks Crob,

I think its important to keep tabs on the efficiency of these circuits. There's is something to the JT circuit and I can see wide applications for it.

Imagine if torches ran on these circuits... thats a project in progress