anyone modify a u2 to a cree?

[cheapo]

i am interested in having this done to my u2, and i am wondering how difficult it is to do. who would i contact to do it for me?

-David

 

[CM]

Re: anyone modify a u2 to seoul p4?

U2 is a boost. Seoul requires a buck converter. Your best option is to modify a Kroma which uses a Lux III. That would be a killer mod.

 

[cheapo]

Re: anyone modify a u2 to seoul p4?

ok... then the cree led... title edited.

 

[wasBlinded]

In the thread "

Cree XLamp LEDs to Power SureFire Flashlights" there is some discussion of success making this modification, but details were not provided.

I would not have expected this to work based on my understanding of the U2 circuit, but perhaps with a high Vf Cree or Seoul P4 and using a single Li-ion cell it will work.

 

[Manzerick]

Does this mean it won't work?

 

[wasBlinded]

Does this mean it won't work?

Some have claimed to make it work. I am surprised, but based on that I can't say it won't work. I'm pretty sure it wouldn't work with two CR123 cells without some kind of circuit modification.

 

[cheapo]

i think 4sevens got it to work with a cree. I am only using 18650s.

 

[CM]

Re: anyone modify a u2 to seoul p4?

ok... then the cree led... title edited.

It has nothing to do with whether it's Cree of Seoul (or Luxeon, or Osram, or...). The LED's Vf is incompatible with the converter/power supply configuration. A boost converter requires that the output voltage is higher than the input voltage so a very high Vf coupled with single Li-ion (or 123) might work as suggested above. However, if you screw up and forget or if someone accidentally puts two CR123's in there, POOF! I can't vouch for whether this would, in practice, work. But until someone proves otherwise, it's just a theory.

 

[cheapo]

Re: anyone modify a u2 to seoul p4?

It has nothing to do with whether it's Cree of Seoul (or Luxeon, or Osram, or...). The LED's Vf is incompatible with the converter/power supply configuration. A boost converter requires that the output voltage is higher than the input voltage so a very high Vf coupled with single Li-ion (or 123) might work as suggested above. However, if you screw up and forget or if someone accidentally puts two CR123's in there, POOF! I can't vouch for whether this would, in practice, work. But until someone proves otherwise, it's just a theory.

u huh... look here:

http://www.candlepowerforums.com/vb/showpost.php?p=1776329&postcount=149

 

[CM]

Sounds like it uses a buck/boost. If you're willing to risk it, I'd say go for it.