Arc LSH

[clarky]

Can someone point me in the direction of any posts that pertain to bumping the current up on the LS's, I want to do it myself. I have had the LS apart several times and am familiar with it but I have been looking for which resistor to use and where to solder it onto the board (I assume on the blank right beside the existing one???), but I haven't found any info worth gambling my light with. Pictures would be great, but won't look a gift horse in the mouth, any info greatly appreciated. Thanks /ubbthreads/images/graemlins/bowdown.gif /ubbthreads/images/graemlins/bowdown.gif /ubbthreads/images/graemlins/bowdown.gif

I saw the .15 resistor, so that helps a little.

 

[Ty_Bower]

Search for "+arc +r15" and you should find what you need.

You are right about where to put it. The empty pads next to R15 are the right place.

If you put another 0.15 ohm there, you'll double the current from 333 ma to 667 ma. Other values can be easily calculated:

ma = 50mv / ( 1 /( 1/r1 + 1/r2 ))

where r1 already equals 0.15 ohm

General recommendations seem to suggest 700 ma as a practical limit. Higher currents give too much heat and too little runtime, with negligible increases in brightness.

Good luck!

 

[Canuckle]

Clarky,

Are you planning on sticking with the stock LED, or are you replacing it with a Lux III?

Cheers.

 

[clarky]

I was thinking about switching to the III.

 

[Canuckle]

Clarky,
I'm following this thread closely. I have 3 LSH seconds pondering their fate. Some, or all, will be modded. Possibly a:

* better 1W OR just a 3W
* better 1W with current boost
* 3W with current boost

Cheers.

 

[clarky]

I think I have decided to go with a 3w at 667 ma even though I'll only get an hour or less from a 123. I'll still have the 4+ if I want the longer run times.

 

[Canuckle]

[ QUOTE ]
Ty_Bower said:

Search for "+arc +r15" and you should find what you need.

If you put another 0.15 ohm there, you'll double the current from 333 ma to 667 ma. Other values can be easily calculated:

ma = 50mv / ( 1 /( 1/r1 + 1/r2 ))

where r1 already equals 0.15 ohm

Good luck!

[/ QUOTE ]

Where would one get a 0.15 Ohm resistor? Searching the Sandwich Shoppe didn't turn any up, with the closest thing being ".22 ohms 0603 5% Resistor".

BTW, what's the '5%' refer to?

Thanks.

 

[Ty_Bower]

Stack two 0.33 on top of each other. It will give you about 0.16, which is pretty close. Or, you can get a 0.15 off a busted Arc LS circuit board (if you have one). I bet Mouser, DigiKey, Fry's, or a similar outfit sells them, too.

5% is the tolerance. It means the resistor you get will be 0.15 ohm, plus or minus 5%. Don't worry about it. You're not shooting for exact values here.

 

[Mic]

Now look what you have made me do /ubbthreads/images/graemlins/yellowlaugh.gif

i just had to take my lsh apart /ubbthreads/images/graemlins/evilgrin07.gif

now i'm watching closely /ubbthreads/images/graemlins/wink.gif

 

[nexro]

I already took my LSH second apart /ubbthreads/images/graemlins/smile.gif
Now, I am looking for a place to buy those SMT resistors...

 

[Canuckle]

Sim Lim Tower would be the best place in Singapore.
Sim Lim Square might have a couple of stores too.

 

[glenthemole]

How would boosting the current work with something like this:
http://www.candlepowerforums.com/ubbthreads/showflat.php?Cat=&Number=482696&page=1&view=collapsed&sb=5&o=&fpart=1&vc=1
Would you be able to use a low resistance resistor and then have just the higher, lower runtime mode and something approaching the normal bright mode?