Joule Thief

[Pirate88179]

@ Xee2:

Bingo!  This is exactly what I am going to attempt with 2 Fuji AA bat circuits.  Good call.

Bill

[electricme]

@Timmy
Thanks for asking about my big torid, about (5 pages back) I not back at home yet, but I will begin on it again shortly.
I have been reading up on the posts the again and had a couple of long PMs to answer        lol.

Yep, it seems that the bigger torids (from what I have read) have a lower output with thin wires.
Mabe I better make this torid a jumbo JT, scale up all components and see what happens.

My lawnmower is kaput, lost its spark, gotta fx this first though,grass getting toooo long.

jim

[electricme]

@ Gary
Great to see you again.

Watch out for those camera capacitors, they sure can give a belt lol

Welcome

jim

[gadgetmall]

Hmm, this circuit (a very basic transistor oscillator with an inductive coupling) is called "The Joule Thief"? Lol,  I can assure you it's more like a "Joule waster"...

Yes, it works with only a few (easy to get or make) components, but that's about all it can do...
It actually works as a (quite inefficient) DC to AC/frequency converter, wasting at least half of the Energy available.

Maybe it's the rather low input voltage where LED is still working that fascinates you?

There are serial (three/four pin "transistor like") components on the market, which allows you >85% efficiency (DC/DC chips, usually needing only a few external low-tech components to work). They all beat this circuit (in efficiency) at least by the factor of two... And they're still not Unity.

Joule Thief? Yeah, sure...

What are some of those part numbers if you don't mind sir . Id like to have a look.

Also here is a 100 watt daylight output running from my Fugi. all i did was short the diode and remove the cap and short the switch contacts . The output comes off where the cap hooked up . i lit 300 leds bright with it also

[resonanceman]

Did you short out the little copper traces where the camera switch was? How did you arrange your switch?

Jeanna

I didn't  have a switch handy .......so  I  just clipped an alligator clip across the  contacts

I didn't use it on a cfl, I used it on a 15 watt fluoro tube. So, the cfl you are using is likely a 27 watt, because that is what gives the =valent to 100watt incandescent bulb. I was able to add a 7 watt fluoro tube later, once that first one was on, and it stayed on too. But not a easily. I bet you are just on the edge of getting the light to light.

I must have  something not quite right .
I  also tried   a smaller  CFL  it was  designed to replace  a 40  watt light ....... if I remember right  it was suposed to use   12 watts .....it should have lit up


gary