When Peter and I pm'ed, I forgot the standard tail amps on these things is 2.3-2.5A amps now. Used to be over 5A when they did a true 1,300 lumens, like the Manker U21 did in my review: https://budgetlightforum.com/t/-/40242.
So the new 2.4A version does about 1,000 lumens. With Peter's doing ~650 lumens, I'd suspect the LED, LED mount, and/or optics, but could still be a driver problem I suppose.
He's right though - they downgraded the light but never downgraded the specs, but if the measurements are good, his is performing below par of even the downgraded model, but the amps drawn from the cell is not producing the same output.
“Just pulled mine off the shelf, well rested, and it does 1070.2 lumens for 2 minutes then takes 30 seconds to ramp down to 745.2 lumens where it sits stable for over a minute and I cut it off, the head is warm to the touch.”
I may not be a mathematical genius but even I can garner that 1070 well rested lumens is much more than half of 1300 ANSI rated lumens. The well rested cell in question is an OLD Moli 26700 sitting at 4.02V.
Edit: For the record, my UT02 with a Sanyo 20700B cell at 4.15V makes 1107.45 lumens. As tested moments ago before plugging the light in for charging.
Edit II: With the 20700B cell charged in the light, it makes 1111 lumens.
FWIW, without the lens mine is making 1159.2 lumens, so there is some 48 lumens blocked via the lens… which actually speaks very well for the lens of choice they put in this one!
Confused now, sure thought it was the UT02 that had a 3A built in charger… now I can’t find if there’s one I have that does or if I just got it wrong. Thanks Giorgo.
But of course, with most USB outlets having a 2A max. Seems there was a light that had more than one USB charging port that could be used simultaneously to charge faster although that’s not where I got the 3A figure, must’ve just made that one up. Sick and tired of being sick and tired…
I ordered last week an UT-02. I will be interested in the details of your build to keep charger and make better driver. Please inform me when you do it. So then If I will be unhappy with performance I can make an upgrade.
Well, after modding 3 of those using r100 and running them moderately for already 3 month( security and hunting mainly, like every night) we could say the driver seems to be stable enough.
3d emitter, tail amps at 4.2, candelas 135k
Do not apply more agressive modding cause the driver will fail, i have several failed so far