Main stream products using joule thief??

[Poit]

I have always wondered why main stream products don't use the joule thief. like, solar lamp posts and head torches etc...

That was until I was at my local Kathmandu shop the other day (popular shop here in Australia). I noticed a couple of their head torches ran off a single AA battery (1.5volts).

http://www.kathmandu.com.au//60977/Head-Torch---Womens-Coupled%5B2%5D.html

in order to power 1 x 0.5W Nichia LED you would need a joule thief... right?

and http://www.kathmandu.com.au//60955/Handtorch-Rebel-50-Duo%5B2%5D.html

What do you guys think?

[NickZ]

  I think that it was all a matter of time. 
  They also have the 1 watt model, but if it only uses an AA, probably only last a few hours.
  In any case,  they are not giving them away,  if they are just Jtc and a couple of led lights,  at $30 or $40. 
  You'll see them shipped free delivery from China or somewhere else for $2.99  soon.
   Thanks for passing that along...

[SkyWatcher123]

Hi folks, well Not sure about products with joule thief type circuits, though I just modified a dollar tree cheapo 3 led flashlight.
It has 3 white/bluish leds in parallel and used 3AAA in series.
So I dug up one of my 1/2" diameter ferrite toroids with 24 gauge bifilar, 2n 4403 pnp transistor, 1kohm base resistor and converted it using one AA nickel zinc rechargeable.
No worries about blowing the leds now and it puts out a decent amount of light.
Here's a couple pics of the dollar torch.

peace love light
tyson

[Poit]

Thanks for sharing... those dollar torches are heaps of fun (to modify!)

good going