SF L4 circuit help please

ok guys, a little while ago my surefire L4 died, and instead of sending it to surefire to be fixed, i decided to sacrifice it to the gods of learning
i opened it up and found that the rattling noise that i used to hear from the head, was the heatsink/head screws coming loose - here is a photos showing where they should be

the screw bouncing around the inside of the head managed to break the plastic of the ends of the inductor


Im fairly sure the Lux V has died, 2 bars in one of the die's flicker when power is applied, i think the heatsink had backed out of the head a little, breaking the thermal path to the outside world, and cooking the LED


my questions to you all are

1. will this broken bit affect the functioning of the circuit ? - it still seems to work , when i apply 3.7v to the bottom contacts i get 9v out the top
2. can i run a Cree (as described in post #23 of this thread
http://www.candlepowerforums.com/vb/...hp?t=162146#23 ) from a 17670 without frying it ? or am i better off finding a new Lux V to put in

Thanks in Advance for the help
E63

Nice, sharp, photos, Echo63. Sorry I can't answer your question. Good luck with your project.

Sounds like the circuit is fine. I just pulled my L4 apart and am going to replace the LED with a X bin Lux V. I just like the broad beam in this light. I've got a number of Cree and SSC based lights so keeping this one a Lux V appeals to me.

-LT

COOL PICS,and people wonder why surefire's are high in price..............

This link may help you troubleshoot.

thats one heck of a boost circuit
the amount of resistors used is ridiculous

chimo said:

This link may help you troubleshoot.

Click to expand...

Is it possible to bump the current up on this circuit? Which resistors may I change & what values?

darkzero said:

Is it possible to bump the current up on this circuit? Which resistors may I change & what values?

Click to expand...

I have not done analysis of the circuit, but it would likely involve changing the inductor current sense resistors (the paralelled R100s) and the one obscured by the red wire.

I don't know if you'd want to bump the current up from what it was stock. It's my understanding that the L4 is already overdriving the led by a fair margin. Maybe if you wanted to drop a cree MCE or sscP7 in there.