Sofirn C8F

I’m new to this community. As my name might imply, I’m not exactly a flashaholic, but I am interested in making an informed purchase for my natural disaster preparedness / bugout bag. After discovering different C8 style flashlights from Convoy and Thofire, I discovered Sofirn’s triple emitter C8F. It looks like a really great unit and the fact it comes with a good 18650 cell and a basic charger is nice. Instead of extolling the virtues of a product I do not yet own, I’d like to ask a question about it. Does the C8F or any other light in Sofirn’s lineup use PWM to control brightness?

The C8F uses a non-regulated MOSFET driver, therefore it uses PWM for all modes but turbo and moonlight, if I'm not mistaken.

Cheers ^:)

Originally posted on Sat, 05/19/2018 - 23:21. Edited for a fix.

That young man is correct. I am lucky enough not to be sensitive to PWM but for those that are I feel for you. C8F, mighty fine light though. I have more than one and they are never far away. Enjoy, and welcome to your soon to be addiction. :smiley:

Some C8F beamshots:

Control

Low1 - Moonlight

Low2

Medium

High2

Bruto LoL!

Cheers :-)

I’ll include one of my own. 30 meters to that box on the ground at the treeline. I had the wife shining the light, looks like she was shining a bit low. LOL

It uses a FET+1 driver, meaning at brightness below 150 lumens, and above that until turbo, it uses PWM.

Darn guys, that sounds really disappointing. I was hoping that it didn’t have PWM because sometimes PWM really bothers me. I’ve outfitted most of the house with LED bulbs and haven’t had much problem with those. I got a few nightlights as part of a power saving promotion by the power company, and the PWM on those is so painfully obvious it really screws with my eyes. Maybe it’s only very cheap drivers that bother my eyes. From the videos I’ve watched on youtube of people comparing a Thorfire vs. Sofirn, the Thorfire’s PWM was plainly visible in the video but not the Sofirn. So I’m torn. I might go for it anyway just to try it out. I have a cheapo Duracell 250 flashlight as my only halfway decent flashlight and that doesn’t seem to have any modulation that bothers me. Surely the Sofirn is better than the Duracell that came in a blister pack of 3.

Well if you end up not liking it or the PWM driving you mad you won’t find a shortage of folks on here that will buy it from you. Between Lightbringer and myself one of us would snatch it up.

What’s that IC next to the big FET then?

Not sure. I’m not terribly knowledgeable in this field. What does that chip do?

Well, if that is the driver I see an AMC7135 next to the single MOSFET (I said previously said dual-MOSFET as I thought they probably used a 9926 like in C8A/C8Ts).

What this means is modes low1 (moonlight) and low2 are attained via PWMing the 7135. I have a big table of measurements and the current draw for these modes is steady at ≈57/208mA, this corresponds to (1/6) and 60% duty cycle for a single 7135.

Cheers :-)

Thanks for the explanation. That’s good news for me, then! As I’m likely to be using it on medium the most often.

Naw, I’ll pass. I got like 3 old C8Fs (tailswitch only) and 1 or 2 new C8Fs (w/ sideswitch). Chrissakes, I don’t even know how many I have. And that’s not counting the rest of my C8 army (buncha Thorfires, a few Convoys, assloads of cheapies for using as hosts, and the latest, a Street-Cat).

Adding a new C8 to my C8 army would be a bad idea. It’d probably get D’Onofrioed in the middle of the night. They’re a jealous bunch…

It’s a Raptor Claw (good; vs Crappy Sailboat, bad) 7135.

Just uses that for lower levels, at or below 350mA. Above, it’s PWMed FET. At, it’s full-on 7135. Below, it’s PWMed 7135.

What's the VS deal? Switching speed?

Cheers ^:)

My guess is higher capacitance on the input line that slows its response so that shorter turn-on spikes just get swallowed up.

Well I ordered the C8F this morning. I had a gift card on an alternate amazon account I had forgotten about, and there was a discount on it too. So it ends up costing me about $27 for the light w/ battery and charger. Can’t beat that.

It’s my favorite C8.

Ok one more question. What amperage cell should I use with this? I’d like to get a couple extra batteries to have around for those times when I need to quick swap and can’t wait hours for a recharge. How about some Panasonic NCR18650GA? They’re 3500mAh, 10A continuous.

These are good. Samsung 35E is another good high capacity/mid drain option.