Fireflies ROT66 Flashlight

I’m guessing yes? The pin layout is pretty full.

   Reset -|1  8|- VCC
 eswitch -|2  7|- switch LEDs
     FET -|3  6|- Nx7135
     GND -|4  5|- 1x7135

There is nowhere to attach it except pin 7, which is already driving the switch LEDs.

You aren’t guessing. Lol

Okay, I just wanted to make sure you didn’t add a special circuit to the D4S driver or something. I don’t follow that thread so I’m not sure. (It’s growing too fast)


The D4S has a different pin arrangement. It has aux LEDs and still has one pin free to do other things:

   Reset -|1  8|- VCC
 eswitch -|2  7|-
 AUX LED -|3  6|- PWM (FET)
     GND -|4  5|- PWM (1x7135)

I got ya. The D4S does not have switch lights so you ran it’s aux board to the “switch light” output. Then, the fact it’s 2 channel (instead of 3 channel on the ROT66) means you have one leftover pin free.

Cool, cool. :cowboy_hat_face:

Beam distance XPL?, Thanks!

As I do not have a ROT66 myself I can only post that I have first Aux board in my GEN3 tail setup finished and limited supply of LEDs and PCBs to make more as it was just first prototype of theese board design

basically the same as usual each LED has its own balance resistor so any combinations are possible

here just 2 rings in same color (ice blue and pink) that are dimable indipendantly with two trimmers,
the central 4 LEDs show low battery warning, the threshold voltage can be set as you wish with a resistor value swap
red for low battery has also its own brightness adjust trimmer, also any other color combination possible if you dont want red for low battery indication

right next to it my new D4S board also in Generation 3 here no circular pattern the trimmers are making a cross around the 4 LEDs

LVP shuts down all LEDs at the 2. threshold level, tested down to 3V, below that the LDO falls out of regulation and it stayes off until battery gets high enough above the hysteresis

Fireflies should have its own first prototypes tested right now but will very likely only bring only a blue and red for low battery variant with next batch

I’ve been away for some time so missed this, which is really interesting.

1: How do I buy one ? and from where ? preferably at a BLF price.

2: Who are Fireflies, what is the track record, is this a skunkworks project for somebody I know of ? (like Sofirn/Thorfire)

3: Clearly the BLF gurus have been involved in the development and are continuing work. Any background info would be welcome (PM if necessary).

It does look very nice.

Cool stuff, Lexel! :slight_smile:

Fireflies is a new company but with some (they mentioned to me) experienced guys who worked for other flashlight companies before (they will not:say which). Before releasing their first flashlight they contacted several people on BLF for advice (they asked me about leds), which is a clever move, but they also have a good nose themselves for what are wanted features and are especially keen on high CRI. That is about what I know. Their first runs of their first flashlight, ROT66, show some teething problems but is seems sofar that they are very willing to solve that for the customers.

Finally got my Nichia version from the group buy.
First I thought they forgot the switch but then I noticed it was only the underdesigned lanyard mount :person_facepalming: .
But there was something black visible on the center LED, after removing the bezel it turned out as a solder clump. Removed it and light is ok now. Glad I checked before running the LED on full for a while which might have have burned the LEDs dome.
End control could be better though.

Bezel was very tight btw. and made a terrible squeaking noise when turning. I added some grease to the threads since I have to open the bezel again in future for a planned mod.

Did a rough lumen measurement with my Nicha version and got about 4800 to 5000 lumens at start, checked my last unmodified Q8 against and they showed almost the same values (within one or two percent), both with 30Q. Very nice tint, Q8 is green in direct comparison. But it gets hot very fast - much, much faster than the Q8. Temperature sensor doesn’t seem to be adjusted yet, after a couple of seconds the light is too hot to touch.
Anyway, I’m pretty impressed with this light!

I have to say, for a first run “showing some teething problems”, I absolutely love my nichia version of this light. No problems what so ever.

If it’s of interest, here’s a build calibrated for the ROT66-219B:

It doesn’t get so hot like that, but it might potentially err in the other direction. As soon as it thinks it’s going to overheat, it glides down to about 2000 lm. The sensor can be calibrated though, and the temperature limit set to whatever you like.

Am I reading the description correctly that the stainless steel tailcap is now standard?

The price on the SST20 version is really compelling considering how close the test results are to the 219B.

Any tradeoffs to Anduril versus NarsilM? From what I’ve read of Anduril, I’m inclined to hope they change to that firmware.

I keep telling myself I don’t need this light, but if I’m being honest, the only reason I haven’t given in yet is I haven’t figured out how to explain yet another light to my wife.

The biggest one is that Anduril doesn’t have Narsil’s mode set UI. There is no mode where you click once per level at start and then it locks in. And the discrete levels don’t fall exactly on the channel boundaries unless you’re careful.

Instead of the mode set UI, it has a stepped ramp mode. It’s like the smooth ramp, but not smooth. Instead of clicking to go up or holding to go down, it’s hold to go up or release-and-hold to go down.

Anduril also doesn’t provide as much control over the brightness of moon mode. Specifically, it doesn’t go as low as Narsil allows. But in exchange for being potentially brighter in moon, the tradeoff is that Anduril uses less than half as much power.

I don’t like the delayed off that Anduril has, it’s not as intuitive as instant off of Narsil. It’s the Zebralight syndrome where anybody who isn’t used to it thinks they haven’t turned the light off and accidentally activates turbo trying to turn the light off. On the opposite hand, Narsil’s moonlight is delayed in comparison to Anduril, but it does go way lower. Overall I prefer Narsil, but the one thing I wish Narsil had was an obvious blink and slight pause when the ramp reaches the light’s max regulated output, of course that will depend on the driver of the light.

The only thing that would make me potentially not order a SST20 high cri version is knowing that luminous emitters tend to vary wildly in cct and tint depending on their output. Nichias and Crees are less prone.

a blink when max regulated current is reached could be added doing one of the values right when the FET starts 0 instead 255 of the AMCs
but you may end up while ramping with a small percentage in this off level

Talking about AMCs...does anyone know how many AMCs are being used in the XP-G2 or SST20 version? Maybe this version would be quite appropriate to be fitted with LH351D. The footprint (3535) should be the same but I’m not sure about the space the (revised?) optic or added gasket would leave for this LED.

351D does not fit under the optics

Just ordered another one. sst20 version. Are they ready to ship?