Joule Thief

[SkyWatcher123]

Hi folks, here is a video using manual pulsing, showing how the initial pulses are dimmer, then as the capacitor fills up more, it becomes more equal with the collapsing pulse brightness.
Though as can be seen, the light is fading once in awhile on collapse due to ringing, i assume.
Without the capacitor, no light can be seen using this same manual pulsing.
http://www.youtube.com/watch?v=-YWmVc6y9KA&feature=youtu.be
peace love light
tyson

[NickZ]

   There is an interesting comment on Yahoo today, telling of an invention by a teenager that has made a battery-less flash light. When looking further into it, this is what comes up, at least for me here. No info available.  Makes me wonder... what's going...
   
on.http://screen.yahoo.com/teens-invent-battery-free-flashlight-230000244.html

[gyulasun]

Hi Nick,

In the video you gave the link to it is said that there are Peltier cells (tiles) used in the flashlight (shown at 1:37). So this means the user's warm hand insures the "hot" side energy to the cells and the metal casing gives the "cold" side to the cells.

Gyula

[NickZ]

  Gyula:
   Thanks for the reply, that link is not opening for me here. So, it's good that you could find out more about it. Interesting. 
                        Thanks, again.
                                              NZ

[gyulasun]

  Gyula:
   Thanks for the reply, that link is not opening for me here. So, it's good that you could find out more about it. Interesting. 
                        Thanks, again.
                                              NZ

Oh I did not think the link is not working for you.  Here are some pictures for you to 'glimpse' the flashlight, grabbed from the video. There was a few second demo how the lamp performes in total dark, but I was not impressed, probably it needs persons with "hotter blood" to make higher temperature difference...