WX1S Luxeon Star on 6AA NiMH?

just received a pair of these low Vf gems from Klaus--one of them seems to produce pretty amazing output with 5.1 V from four depleted AA batteries in a holder /ubbthreads/images/graemlins/huh.gif ...

I'm thinking of running one in my Blaster on 6 NiMH AAs, but am concerned about the low Vf (I won't be using the one that cranks out on 5.1V /ubbthreads/images/graemlins/wink.gif I want to try a 6V DD mod with that one)

I'm planning on replacing the existing star (held to the sink by two screws) with it and adding a little arctic ceramique poxy for good measure

would appreciate some input from those of you who've done your own 5W mods--yeah, you can fill in the poll, too but I'd really value your constructive comments even more

hideo

Re: WX1S 5W LS plus Blaster 6 = ?

yikes, no comments from the most opinionated forum on the Web ... /ubbthreads/images/graemlins/frown.gif

tell you what, I'm not concerned about the poll but I would like to hear from those that know about running a well-heatsinked "S" Vf 5W on 6 AA NiMH batteries (open voltage about 7.8-8.0 V) ... would you do it or not?

thanks in advance,

hideo

Re: WX1S 5W LS plus Blaster 6 = ?

hideo,

I essentially have an S-binned Vf 5W (it started out as a T-bin, but experienced the elusive and mysterious Vf drift that we've seen on a few luxeons.) Its Vf is about 6.24V at 700mA.

With 6 fresh AA NiMH batteries and about 0.7 ohms of resistance, initial current was about 1.4A (way too much). I ended up building an LDO linear current regulator to drive it at 750mA.

So I would suggest about 2 ohms or more of resistance for driving it from 6AA NiMH batteries (if you're going to use a resistor), or one of the various step-down driver boards (downboy or one of georges80's driver boards) to drive your luxeon - that will extend runtime even further than using a resistor or linear regulator would. You're looking at dropping at least 1.5V for the majority of battery life from rechargables, and more like 2.5V+ if you use regular alkalines.