Joule Thief

[Pirate88179]

I just ordered a large breadboard from electronics goldmine.  And, as long as I had to pay the shipping fee, I ordered a .47 Farad 5.5v supercap to play with and two 265,000 MCD (not a typo) super, super bright white LEDs.  Now I have to wait until this stuff gets here......I hate that part.

Bill

[markdansie]

hi Bill,
I was wondering if you made any progress on measuring power in and power out yet.
Kind regards
Mark

[xee2]

@ markdansie

Here are some tests into a resistor load.

[Pirate88179]

Not as of yet.  I had two cases to work today, the first starting at 5:00 a.m.!!  also, I am not so sure how to do this.  I know others have posted to me on how to do this but, I get my meter probes next to this thing that has zapped me many, many times, and I get a little squeamish.  I did try once and set my DMM to the max volts setting (not power) and I got an error message.

I have a few thoughts about this.  I really want to measure the power when all 400 leds are hooked up, I think that would be the best test.  From what I have seen, this thing puts out more and more as the load increases....to a point of course.

My first little 6" FL tube was really not all that bright...I mean it was on but I was not hopeful ( you can see the pics) that any larger tube would be any better, but they were.  The 18" was brighter as was the 48" tube.  the two 48" tubes were brighter still.

Now, as shown in the posted pics, 100 leds were too bright for their own good, 200 were very bright, 300 were also bright but 400 were not as bright as 300 so, I guess I was reaching the limits of this circuit.

I will try to get some power in/out readings because I think these circuits are more efficient than the numbers xee2 posted.  I am not saying he is wrong by any means. (He knows more than I do about these circuits)  I guess I am just going by a gut feeling that looks at all of those leds illuminated and then I look at that small AA battery.  Maybe this is all standard transformer stuff I would know if I were more educated in electronics but, I have to say at this point that I have never seen anything like this before i got involved with these experiments here.

I would have thought that if circuits like this were readily available then, you and I could have purchased a 48" FL tube powered by a single AA to take camping with us.  I have a camping light with a single 6" FL tube and it uses 6 D batteries and will only light for about an hour before the batteries go dead.  so, maybe they didn't spend the money on this cheap little circuit?  if they knew about it and did not, that was a bad business decision, even though this happens all the time.

So, long story short, I will test and get back to you.

Happy New Year!!!!

Bill

[jeanna]

HAPPY NEW YEAR EVERYONE

May everyone's lights be bright in this and all coming years

jeanna