[Optisolis/E17A/E21A] Jetbeam Jet-µ

I will surely take 3 different CCTs of Optisolis (6500K, 5000K and 4000K or 3500K).
Again, I am too weak to resist.

Hard to go wrong with Clemence.
My most used lights:
l-r E21A, N219b 4500k, N219b 4500k

Yes, a Slow Green campsite beacon in Rural Jungle seems fine.

As a pedestrian, or cyclist, in the Urban Jungle, I would want Fast Red or Fast White flashes.

Lovely work Clemence. I’m starting to love my Sofirn C01 and I’d definitely get this. E21A 2000K and optisolis 5000K would be my first choices for this light.

For a better idea of what has been accomplished, comparisons can be made with the review UPz provided.
Optisolis 5K 9080 output similar to a Nichia 219B sw45 92+ Cri …but with better runtime and final slope.
Truly a well executed labor of love from our Mr. Wizard !

Thanks Tjohn =)

BTW, I made some optic refinement for the JetE21A and still doing a runtime tests between packing the orders. The beam pattern is now looks almost similar to stock Cree XPE2 and the output increased to about ~10ish lm (will measure it again). The LED also runs cooler now. Will report back soon.

Happy saturday night guys

Where did you get those nice little LED boards?

I grow them in my backyard :laughing:

No, I made them of course. But this only designed for up to 350mA. Just normal good copper MCPCB. At this power level even the stock aluminum non DTP MCPCB already more than enough. I made them with copper because I am pretty sure you guys will question me if it’s only aluminum :stuck_out_tongue: . In my test, it’s shows no measurable difference at all (Cree XPE2 250mA current).

- Clemence

I hope you will ‘harvest’ enough of them so i can buy a few too with my next order.

Thanks Tjohn, that really puts it in perspective. The 219B used in the Eagtac judging from the Eagtacs I own, are not even 9050 because I have real 219B 9050 to compare with. I think those are just 219B 9000, which is usually much more efficient than the better color rendering, better tint versions. What Clemence is making is absolutely amazing since the 9080 or more like 9090+ Nichias will look FAARRR better and still offer about the same or better efficiency as the 219B Eagtac.

So far I recorded 74lm (79,11lm at start) for 1hour 3minutes uncooled for the Jeteria (JetE21A)

- Clemence

……to further your point even more, I used to think my Eagtac MX25L3C Nichia had much better tint, until Clemence drop shipped the first Group Buy of sw45 9080 Nichia leds via Texas Ace, before his Bali store opened.
Those jewels make my D25aaa and Eagtac Nichia 6 led thrower look mucous yellow-green in side-by-side comparisons.
Indications are Eagtac looked for above the ANSI BBL stock for more lumen output, since according to Clemence, above or below was formerly the typical manner in which Nichia offered their sw bins.

I just found this thread & happy I did. I love this little AAA light, & have one in my pocket all the time.
Looking forward to this one…… :+1:

Still testing the runtime for the third time. There’s something weird going on here.
The JetE21A output vary between 74lm - 79lm between lights. This is OK because I measured the current output vary from 230mA to 245mA, and each LED’s output also slightly different. In theory and observations, hotter LED will have lower forward voltage, correct? This usually results in longer regulated runtime albeit reduced brightness. This apply to either boos or buck driver. But in JetE21A the case it’s the other way around: uncooled (much hotter body temp) results in LESS reduced output over time and LONGER runtime! This is weird
Can someone help me explain this?

- Clemence

I don’t know what could cause it but I experienced something similar with a Lumintop Tool AAA. Output was higher and more consistent without cooling. Runtime was longer just like in your case. After I turned a fan on, the output dropped following a slight increase in output. Maybe it does have something to do with the Vf being higher with lower temperature.

One possible cause could be the Eneloop drains more at hotter temp. The tube temperature was 40 °C. Anyway, this is an unexpected benefit in hot wheather. But expect reduced runtime in colder temperature. Did you use Eneloop in your test?

- Clemence

Yes, it was the normal white Eneloop.

Hmmm looks like better NiMh chemistry in hotter temp is the case. For the Jetsolis the voltage could be too high for the boost driver that better battery chemical reaction is not enough to boost the runtime.

- Clemence

Maybe test it with a bench PSU.

Yup, that’s what I thought too.

- Clemence

Standardized testing of batteries is done at 20°C to 25°C, but most batteries (including NiMH and Li-Ion) actually work a bit better at higher temperatures. At temperatures of around 40°C to 45°C (or even up to 60°C) the voltage level is higher and you get slightly more capacity and a decent amount more energy out of the cell. This info is unfortunately not in the Eneloop datasheets, but I found a graph which was on the eneloop.info website back in the day.

Some datasheets of Li-Ion batteries (e.g. the UR14500P datasheet) have such a graph included.

While higher temperatures are good for getting the maximum out of the cell, they are also detrimental to the life of the battery, but that is of course a different topic.