sean
08-09-2005, 13:12
I made a headlamp using 2 leds and 2 AA batteries.. The cost was $1 for the batteries, 20 cents for each led, and 50 cents for the switch (which broke when I dropped it at night comming down moosilauk This is less than $2, and I have crossed many mountains through maine and new hampshire at night. I was able to stuff a wire back in to make it come on again now the switch is out. I even added some resistors so it can be dimmer (and last longer) I measured the current draw before I left to be 20ma at the 3.2 volts, so the light should last about 300 hours, but because the voltage of the batteries will drop, I am guessing this may be increased to 400 hours (although dimmer)
I wish I had used aaa batteries instead to save weight, but the run time is about 50%.
This is kind of boring though
The simple way is to just tape a single led to a watch battery lithium battery (3.0v) so when you squeeze it, it will turn on.
I wish I had used aaa batteries instead to save weight, but the run time is about 50%.
This is kind of boring though
The simple way is to just tape a single led to a watch battery lithium battery (3.0v) so when you squeeze it, it will turn on.