FW3A, a TLF/BLF EDC flashlight - SST-20 available, coupon codes public

I’m hoping to swap some sw45k’s into one of my FW3A’s. When the time comes, how would I go about disabling the FET in firmware? Am I correct that this would require a coding change and then recompiling?

This has come up a few times, so I’ll probably make a config specifically for it. I just need to remember to actually do it…

That would be much appreciated!

I think setting PWM_CHANNELS to 2 in hwdef-FW3A.h would do it. You could also redo the PWM levels in cfg-FW3A.h to use the FET, but only at a low duty cycle.

FWIW Maukka tested his review sample with sw40s and the output was acceptable with a GA. I suspect the LEDs wouldn’t fare as well with high drain cells, so it comes down to either only using the light with GAs or limiting the FET output in firmware or disabling it completely. It’s quite doable but the level you limit it to will depend on what cells you want to use.

Ok, I give up. Please put me on the list for 2 of these.

Also, as far as not using the FET is concerned, couldn’t you just set the top of the ramp to the highest regulated level? Then it would never use the FET, correct? I guess unless you double clicked for turbo… hmm…

So how would the ramp look if you didn’t use the FET? Top of ramp at 75% regulated, then fully regulated for turbo?

Interesting. I just can’t imagine not wanting the option of more lumens if you really needed them.

...

:smiley:

Once you start rewriting the firmware, you can specify any behavior the hardware is capable of. I’ll play with it a bit and may end up with something like a 25% duty cycle with the FET for the one I put 219Bs in. I probably want the behavior of the light to feel the same, just with a max level that’s safe for the emitters.

I don’t want to give up output I can actually have with the LEDs I’m going to use. 219Bs given too much power will turn blue and output will decrease. The emitters might potentially be permanently damaged in the process. That’s technically true of the emitters the FW3A will actually come with as well, but the hardware will not be capable of delivering that much power.

Oh! That’s what I get for not paying close enough attention. I was under the impression that this was being done for battery life/heat management. What you say makes sense though. Even Anduril on the D4 and D4S has the FET limited on the 219c version if I remember correctly, for that reason.

I didn’t realize the 219b was that sensitive.

Thanks!

Yep, 219Bs shouldn’t be driven at >2.5A for more than very short bursts if I’m remembering right. That’s VERY easy to exceed with even lower-drain cells, they can put out higher current than even the rated burst drain in a FET-driven light.

I just want to make sure there’s no chance of damaging the emitters. It seemed to me that disabling the FET was the safest option.

The 219B is rated at 1.5A, compared to 1.8A for the 219C, so nominally they don’t look much different, especially since the newer V1 219b’s have similar voltage curves to the 219C. However, the 219C is already known to be working very hard on the D4, so the concern is increased when the current your battery can supply is shared between one less emitter, and that emitter has even a slightly lower current capacity.

So dialing back the current for a 219B mod is very likely prudent.

A benefit to modifying the firmware rather than just setting the ramp at a safe level is you retain the short-cut to the firmware max level. Shortcuts are a great feature of firmwares like Anduril.

A firmware modified for the 219B might also be well-suited for the E21A, and Clemence is planning an E21A triple board. However, Carclo says the 219B should have more throw in the 10511 optic than an E21A.

Added some extra info to comment #3 — about the driver, and about the optics and beam pattern.

Also updated status in post #1.


- TK

Will it be possible to buy a spare driver?

How about spare clips…!

Please add 2 more for me, thank you.

I have no idea. I’ve been trying to get confirmation on a variety of extras… but most of those questions just disappear into the void. In particular, I’m hoping there will be a diffuser cap made to fit it, to allow it to work as a candle or lantern. But I get the impression this sort of question won’t even be acknowledged until after the light itself is in production.

will it be possible to drive a spare buyer?

Very excited to finally see this come to fruition! Can’t wait to be able to order mine. I’ve got the money reserved :smiley: