ZY-T08 Mod - picture heavy with beamshots

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Cula's picture
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Joined: 11/14/2014 - 02:04
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Location: Croatia
RMM wrote:

Gj wrote:

Maybe try a couple of 4.35V cells.

If you get 4.35v cells, get the LG D1s, not the E1s.  The D1s pull more amps.  A freshly charged set of 25Rs will still pull slightly more amps than the 4.35v D1s on the newer emitters, but after a few minutes the D1s pull ahead.  

These LGD1’s look very nice. I was thinking of buying them few weeks ago but that meant I’d have to buy new a charger so I gave up on that deal. We’ll have to wait till 25R’s arrive and see what happens. If freshly charged ultrafires gave 4.4-4.5A it could only be better with samsung’s. But frankly, I don’t give a damn. Even if it stays at 4.5A it throws farther then I need.

Just for the sake of my mind, is there a way to push these new XM-L2’s beyond 5A without using a buck driver and 2s cells?

DB Custom
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They fry quicker than the old ones.

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Joined: 06/04/2012 - 15:18
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Sir, if this is what you accomplish with your first attempt at modifying flashlights than the old hands here will soon be learning some things from you.  Very well done.

Cula's picture
Last seen: 7 hours 39 min ago
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Location: Croatia
ImA4Wheelr wrote:

Yeah, that is pretty high.  If you look at djozz’s chart above, his older XM-L2 had a Vf of about 4.65 3.65 at 4.4amps.  Decent cells will sag to 3.9 volts under even at just a 1 amp load.  Sounds like you identified your issue.  High emitter Vf and cell voltage sag. 

Bet you’re even happier to have some 25R’s on the way now.  Please report what they do tail current wise.  I’m curious.

I owed this information when 25R’s arrive so here it is.
Max tail current measured (1s2p) is 4.55 Amps when freshly charged to 4.20V but Samsung’s hold voltage very well under load, much better then ultrafires. I suppose that with two parallel 18650’s this is as good as it gets with newer XML-2 emitters :beer:.
Just wondering would FET driver push this emitter higher than this.

Last seen: 1 day 15 hours ago
Joined: 02/03/2013 - 14:51
Posts: 7860
Location: SC

I don't know much about the LD-1.  There should be someone here, including it's inventor, that may answer your question.  I'm sure you know of this thread.

The easist way to answer the question would be go by-pass the driver and measure current.  A good FET will probably get close to that level of current.

Looking at your OP again.  Man, that is a sweet light you built here.