From the descriptions it seems there is no low voltage protection. “When light gets dim, recharge”. I wonder if you solder in a protected battery if that just would work, including resetting a tripped LVP when it is recharged.
Btw, the UI is a high-low-strobe-off cycle, with no detectable PWM :+1: on the low setting.
Only bad point so far, the worst looking o-ring i have ever seen, looks like it`s been punched out of some rubber/silicone and has excess still attached, and it looks like it will break just by looking at it, easy to replace though.
John.
Trying to run down the battery, I’m at 2.72V now. When at this point I switch on the light it starts bright (-ish 
) and within seconds turns very dim. So the advice does work: the stock battery struggles to deliver any power under 3V and so you are notified to charge it at a still safe voltage :party:
Cool thanks, I grabbed two of ’em.
One of the user pics in the reviews section of the aliexpress link shows both red and green button lighting, so maybe the button turns red at low voltage? Or maybe red when charging. I can’t read Cyrillic.
The power button lights red while charging and turn green when full, I dont know if these is any low voltage warning.
It seems to draw around 450ma while charging, this drops as the battery charges.
John.
I’d be interested in knowing the parasitic drain from that e-switch. (I suspect you won’t have to wait long djozz, as it’s probably rather high. 
)
Parasitic drain is something to check too, yes.
I just removed the battery and put it in the Opus for capacity check, in the meantime I soldered another battery in 
It almost fits (had to cut away a tiny bit of plastic)
I did not check before, but the light does 130 lumen flood now. That can only be better with another led. (and thicker wires, tweaking the driver, etc.)
also looks like ...
FIX U UP DIE !
You do not even have to read it loud backwards, creepy!
Mine does not have any logo on it.
I have seen a smaller non zoomable version for sale, but I prefer the zoom myself.
I wish the high and low had a bigger spacing.
John
Double-click or single click into strobe mode? Long or short press for on/off?
So let’s say 100 lumens with the original battery… that’s actually incredible for the price. Imagine that when I started this hobby I was thrilled with the maybe 15 lumens put out by this light, which actually cost more than this zoomie, and didn’t come with a battery or an integrated charger. :money_mouth_face:
No, just clicking forward: off-high-low-strobe-off-high-low-strobe-off-high etc.
The next iteration: dedomed ‘Mitko’ XP-E2 R3 0D on a Noctigon, glued in with AA-Adhesive (because I can…)
Surprisingly, the output in flood has not increased, still 130lm. But for the rest:
-infinitely better tint (0D’s dedome pretty nice)
-infinitely better beam (took care of most beam artifacts, and the XP-E2 die just looks better)
-better throw (I measure 24kcd, which is about half of the max that you can get with this size lens)
Slowly this is becoming pretty decent
…and the results are in:
310 mAh, not great, as expected, but not really bad either, HKJ has tested lower capacity 16340 cells.
How many amps is it pulling on hi and low ?
I can’t tell without unsoldering wires, next time I have it apart I will measure current.
I can have a guess of course for a ballpark number: 130 OTF lm in a zoomie may be 180 ledlumen, roughly times three gives current, so 550 mA ?
Low gives 25% the output of high, so maybe 130 mA ?
As requested, the current measured over the ledwire:
Next little step:
I beefed up and shortened some wires here and there and it did not help the output much.
But what are those 1.2 Ohm resistors doing in the led- path?, that is not very BLF!
Ah, that is better, how’s the current now?
That helped, just doubled the current, 1.4 A is quite right for a XP-E2 on a Noctigon, with average heat path.
I guess I will have new output and throw numbers, re-charging the little light now….
I’m having a lot of fun with this light sofar! Budget lights rule once again!
That’s the BLF spirit, djozz! :+1:
Thanks
And I’m sure if you seriously go into minimising all resistances, and solder in an Efest IMR battery, you get 2+ amps to the XP-E2 and more to lower voltage leds.