[Review] 77 Outdoors D25 Headlamp (18650)

No, I’m not sure if the XM-L2s are authentic. Since the overall performance of this light is rather low it will not matter to me, though.

Yes, you‘re right. It’s about how we define a „driver“. IMHO, putting two wires and some resistors in between onto an LED is not what I really call an actual „driver“. Maybe I became too spoiled already. :wink:

I don’t mean to argue about that but one thing is for sure. Those fins inside the battery tube work as a thermal conductor between the hot area underneath the LEDs and the battery, deliberately or not.

Have you read this thread? You know this is a FET driver, right? It’s got two FET’s so I assume it’s a 2 channel driver. The big resistors your referring to are to simply limit the maximum current. So this driver is just as complicated as some of the other 2 channel FET drivers such as the one in the Q8.

The MCU and UI are not as advanced as the Q8’s Atiny 85 and NarsilM, but the basic driver design is similar.

It’s a 1 channel driver with 2 mosfets and resistors in parallel and firmware without stabilization.

Just wanted to add that I have the D25 and I love it. I have several headlamps and this one is by far my favorite just due to the weight and usability (Simple). Seems to hold position well and the brightness levels are good for me. I am thinking of getting the D10 just to see how well it works. Also it’s inexpensive which makes it a great buy.

Thanks, I see the FET’s share their inputs and outputs. I should have looked closer. :person_facepalming: I wonder why they used 2 FETs when one should do?

So not quite as complicated as a 2 channel. I guess this makes it difficult to get really low moonlight levels.

On the plus side there is no viable PWM as far as I can see and it has low voltage protection. Two things the old RJ02 suffered from.

D25S headlamp is available on Amazon US now, featuring two SST40 emitters for 1200 lumens and better UI. Check this page

Thanks for the heads-up, Barry. That UI sounds a lot better. It would be nice if Low could be lower than 70 lumens, but still a big improvement. :+1:

Also… Any news on the upcoming SP40A/B?

Here is a photo of the latest driver (with original MCU still soldered) from a D10 I recently purchased. This particular D10 uses the same driver version as the D25 I have. The only differences being the current limiting resistors used (1 vs 0.68 Ohms)

It would seem that the circuit and MCU difference are as a result of the headlamp release versions (ver:01 vs ver:03) rather than the headlamp model (D25 vs D10) itself.

The good news, as far as I can tell gChart’s MCU RampingIOS upgrade works fine with this D10! The bad news, there’s no way of telling externally whether a given D10 (or perhaps even D25) will work with a new MCU.

FWIW, both of the headlamps that worked with the MCU upgrade (T02-A VER:03) were purchased within the past 2-months.


Edit: The D10 with ver:03 driver that works with the gChart MCU upgrade was from the Official Boruit Store on AE.

Interesting! Thanks for the update. And glad the MCU swap is working well for you :beer:

So if it’s just a matter of driver versions and not D10 vs D25, that does make things a bit less predictable. But on the plus side, the driver is labeled where you can see it by just removing the switch cover. No need for a full tear down to find out which version you’ve got. Also worth noting, Flail’s “VER: 01” also seems to have physical debounce resistor+capacitor on the switch side. They must have eliminated that (using firmware debouncing?) in later versions.

Edit: link to where you got your D10? I know there’s plenty around, but it might be handy to know who is selling one with the newer driver.

Just for the heck of it, here’s a video of the D10 Ramping (I’ll remove if it gets annoying or takes up too much bandwidth) -

The reason there’s no blue or green tint shift in the beam -> the emitter’s a Nichia 219B 4000K :smiley:

Nice! :smiley:

After chatting with pc_light a bit about this idea, I added switch LEDs to the D25 tonight… quick and dirty style.

The switch detection pin is pulled high at the MCU using the internal ~35 kOhm pull-up resistor (at least on my transplanted attiny412). So… I just piggy-backed that and stretched 0805 LEDs across each side of the tactile switch.

At first I tried green LEDs, but it acted like the switch was constantly being pressed, which I was concerned might happen. I think the vF of the green was low enough that the MCU was detecting the ground. I switched to blue LEDs and voila! It’s currently acting like it should. Who’s to say if it has any long term effects.

PS - stretching the solder to the 0805’s was tedious. If you have slightly larger ones available (1206?) you might try those.

PPS - the clear tailcap I used is 14x6mm, item #S024947 at Kaidomain.

gChart you are turning these D10/D25’s into must have budget headlamps :+1:

What’s the mA draw?

I haven’t measured yet, but with the resistance being around 35 kOhm, I would suspect that the LEDs themselves are only sipping around 0.05mA.

Edit: look there, I just hit 1500 posts. Woohoo!

Sofirn should have hired you to design their improved D25. :slight_smile:

Its a pity.
Yesterday I wanted to solder the Attiny from gchart. But I have Rev1 and it didn’t work.
Once I connect the battery it switches on at low level. After (not while) I pressed the switch it dimms down to lowes mode. And there is no way to make it brighter or switch it off.



Some Quotes for reference:

i’m glad i found this thread, i have several d10s and d25s, i know this thread is mostly about modding the driver, d25 seems to me is completely out of focus, i removed reflectors, and installed a poly window instead, turning it into a mule, works great, would be better if it was not so blue, but i can live with it, i think d10 is much better light, focuses right, does not heat up as much, needs no thermal regulation, with stock driver, and you can easy replace a led… but i have a question about the bracket itself, i lost mine, (actually i did not, my cat chewed it up) i tried one from ZL and skilhunt, the light can be forced it, but they flex, you can’t turn it so it stays in that position , not without 1 hand holding a bracket and another twisting the light, and they have no ability for light to be removed in half a second, as original does. anyone knows where to get spare? i’d 3d print one, if i could design a stl, i can adjust an stl file, but can’t make one from scratch. a can do a blueprint on paper easy.

Short of buying a new headlamp with a strap or using a generic rubber-ring strap, I’m not sure what to say :frowning:

I have a 3D printer as well and am pretty decent at design, but I just got rid of my D25 so I can’t measure dimensions.

this is my d25 mule.

if anyone needs spare reflectors i have 2.

in that case i have a business proposition for you, i’ll send you a brand new d25, i have one nib. (i got several, they make decent presents) would you be willing to make an stl, and post it here so anyone can download it, and print one if they need? make one with your name on it so everyone who prints knows who designed. brackets are identical for d10 d20 d25.