Joule Thief

[mscoffman]

@all

Would a JT Joule Thief improve the Scrunch Lite?

I recently purchased an inexpensive hand rechargeable 3 led flashlight
at Walmart recently like the one at this web link:

http://www.amazon.com/AmerTac-75202M-Scrunch-Lite-Colors/dp/B0037IP5CA

It would be interesting to attach a JT joule thief to it to run the three
white leds and see the change in performance. One could discharge
the battery entirely and pump it for a certain amount of time and track
the voltage decrease on the battery to see if the JT made sense to
improve the performance of this application.

:S:MarkSCoffman

[Pirate88179]

(3rd time trying to post this)

Yes, the JT circuit will allow you to run longer and brighter on just 1 battery instead of 3.  You could wire the bats in parallel for additional longevity but, you will probably need to remove 2 of them to get the room inside for your circuit.

A really cool thing would be to stuff like a 10 F supercap in there too.  A few trigger pulls to charge the cap up and it should run for a bit.

Let us know here how you make out, that sounds like a good, practical project.

Bill

[conradelektro]

Joule Thiefe flash light with air core for a "used" AAA-battery

I post something very simple and down to earth (nothing special for a change). It is a Joule Thief circuit with an air core (instead of a toroid). The air core allows a high frequency of about 1 MHz.

About every 15 months I get 30 "used" AAA-batteries from my house alarm system. The batteries still show about 0.9 to 1.1 Volt when they are rejected as "low battery" by the window and door sensors.

The "flash light" was designed specially for those "used" batteries and gives many hours of light with a single "used" AAA-battery. When the battery gets weaker a jumper can be set to light fewer than 5 white LEDs.

I admit that one does not need such a flash light very often but it was fun to build it.

Greetings, Conrad

[freepow]

  @ conradelektro,  Good one !  Great to see people like you and others making use of so called
                             "dead batteries" when everyone else chucks them away !!!

                             I'm working on a very nice project for our house, It will take a little while, but when
                             it is finished, I will post pictures of my nice house project.

[wings]

@ conradelektro,  Good one !  Great to see people like you and others making use of so called
                             "dead batteries" when everyone else chucks them away !!!

                             I'm working on a very nice project for our house, It will take a little while, but when
                             it is finished, I will post pictures of my nice house project.

agree
nice job