As previously mentioned, i've got some RC-230 cateye halogen lights and a 7.2v nimh battery. I was thinking of putting an LED upgrade into one of the housings.
Now, I've just had a thought... I've got an AllTeamGo Cree XR-E P4 bike light already, but it runs at 4.5v (3xAA).
How do I reduce the input voltage from 7.2v to 4.5v? I presume I can use a potentiometer or a resistor, but it's 20 yrs since I touched electronics theory at college and can't remember diddly.
(I think the LED is directly driven so I don't want to risk burning it out)
Cheers
You could have a resistor in there, making a potential divider to sort out the voltage, i believe the cree is normally ran at 3.7Volt, (maybe wrong) but what you need is a buck puck...
to bow out i would suggest http://forums.mtbr.com/forumdisplay.php?f=124
but i wouldn't directly drive it...
An Led needs some sort of electrickery to make it work as they run on constant current at 3.7v (ish)
Your led light will have something in it to reduce that voltage to 3.7 volt. Could be a resistor but probably a more sophisticated constant current controller
If you use a resistor you lose some of your electricity as heat. Much better to use a buck puck or other proper controller.
Try candlepower forums for more detailed stuff.
Just starting from scratch isn't a possiblity ?, using only the Batts and chargers you already have.
Just a thought.
S.
the light that i've got does have some sort of controller circuit board, but the details are sketchy on [url= http://endless-sphere.com/forums/viewtopic.php?f=3&t=3491&start=0&st=0&sk=t&sd=a ]here[/url]
solo - I was thinking of trying to reuse as much of what i've already got instead of buying new bits and pieces..