That sounds right to me. Keep up the good work. :+1:
I hadn’t ever looked at “BLF” in Morse code before. It seems to be one of the easiest patterns possible, almost like 1 2 3… kinda neat.
_ . . .
. _ . .
. . _ .
Continuing the pattern, the next letter would be V … but I don’t know what the V would mean.
About the ramp shape, it’s right there in Narsil.c linked a few posts ago.
The tool to calculate ramps is bin/level_calc.py in the firmware repository. It has lots of options (some of which require small code edits), but by default it uses the cube-root model for estimating what would be “visually linear”. To change the ramp shape, edit power() and invpower() at the bottom.
In my testing, I’ve found Narsil’s ramp to be very very smooth. I can’t tell where the FET comes on, and it appears to ramp at a constant speed. It might be a little slower on the FET portion, but mine (SRK w/ Q8 driver) is 3000 lumens instead of 6000, so on the real Q8 I think it would be just about right.
Just ordered a set of HG2 for the Q8
Ooh nice Thijsco has his as well
5 of 7 arrived
Tom has fixed the bugs!
If somebody is able to help test this latest version that would be awesome!
What is also awesome is that you TK seemed to have read my mind from the future (well when you posted that Morse it was future now it is present) for seeing that pattern I wanted to see what the next was and you already looked it up
For the ramping se are of course looking at perception nicely described in the Weber–Fechner law.
From PMs I get that Lexel mainly talks about the triple channel ramping that does look good and natural just has a very short ramping in the FET region so it is hard to select FET brightness .
This does not apply for the Q8 with its FET+1 for it switches to FET modes above 350mA so a lot of time to choose several FET driven brightness levels.
Yes - the BLF Q8 driver is two channel, but for the new FW3A, the driver will be 3 channels.
Yes - brighter levels include the 7135 full on, but on the max level, brightest setting, it's FET only. We found it's more efficient giving all the amps to the FET for resulting maximum amps to the LED.
Triple channel drivers can have 2 or more 7135's in the bank. We (or I, not sure) call the channel with the multiple 7135's a bank. I've used boards with 3 to 9 7135's in the bank but the bank can go much higher. Texas_Ace has a large selection of exclusively triple channel boards, including SRK versions up to 15 7135's in the bank here: https://budgetlightforum.com/t/-/40540, while Harley's SRK board is versatile enough to use as a triple or 2 channel board here: https://budgetlightforum.com/t/-/40540.
pilotdog68 was the first one to create an open source driver using 3 output channels here, back in Dec 2015: https://budgetlightforum.com/t/-/37080
For ramping in triple channels, when the FET kicks in, the 7135 channels remain turned on full, up til the max output. Sometimes you can notice the slight bump at the max level when the 7135 channels are turned off.
Thanks, I’m slowly learning this stuff.
Is the 7135s voltage drop that cause the less power reaching the led ?
I'd be guessing, but sounds like it could be.
What batteries are recommended for this flashlight?
I’d go for Samsung 30q button tops.
Hopefully they’ll be available over at nkon.nl soon.
Yes at beginning of OP is link to Yoms cell test results
Grandpa Yom, I like it!
Only my mother can call me Yom, or Yommy
Hahaha Yom , how #*## autocorrect suggests Tom You and Ton
So my previous post Yoms = Toms
I am a gambler so i went with Sony VTC6 or whatever they are called, unprotected and flat tops, so i am in the process of evaluating if i should just do a solder blob, or actually solder on a little 2 - 3 mm cobber disk for a more pro look.
But i am a lazy old bastard and i am not sure i can find my little cobber disks in the mess that still prevail after i sold my house 6 years ago and moved into this temporary apartment.
Only opened about half of my moving boxes to get by, the rest are still stacked up and unopened.
At least my little cheap soldering station are unpacked years ago, cuz as you know a real man cant go by without using a solder iron at least every 2 month.
we still use 7135 on this big light
Why we dont use a driver constant current fet like the one already in this forum(lq-2, i guess)
I am thinking about using MCU, control the DAC (for example, mcp4921 12bit DAC), go to op-amp, control the fet
If only my programming skill is high enough to create some driver :person_facepalming:
Are you talking bout LD-2? It's not open source, great driver, but he chose to keep it commercial, not in the open source community - the cost would be much higher. I don't think it can do smooth ramping based on the design - it's got limitations.
We contribute the board design and firmware and leverage China manufacturers to build them, best of both, keeps the cost down.
The Texas commander is the same priceable and open source. The issue there is that it can’t regulate more then about 2-3A before it would overheat. There are ways around this but with such a large driver it would be better to simply use a buck driver and setup the cells in series. Then you could regulate the power and not use PWM all at the same time.
Buck drivers are hard when space is tight like in 17mm drivers. Just not enough room to use the components you need. The inductor alone takes up the whole 17mm pcb.
The pwm-ed FET driver of the Q8 is simple and cheap to build, incredibly robust and hardly produces any heat at the used 20+ amps. With the almost optimal voltage difference between batteries and the used XP-L2 leds it is also rather efficient.
Using a non-PWMed FET driver a la LD2 greatly complicates the design and makes it very expensive.
(try find an affordable FET that can take the enormous heat of limiting the current to 10A )