I think the moonlight on the FW3A is fine. And actually the one on my D4 is fine too, I can use them at night without scarring my retinas or waking my wife, and I have blackout curtains. What does surprise me is those two lights have lower moonlight than many of my other lights, even my Moonlight Specials (1+7 AMC7135, which use 1x7135 for the moonlight). Does anyone know why that is? Just a curiosity.
Anyway, my ZL, my D4, FW3A, and my L6 all do moonlights low enough to stare directly at the emitter. My Jetbeam will do moonlights so low that I have to overexpose the ZL moonlight just to capture the RRT-01's output in the same image.
My understanding is that the single 7135 350mA chip output gets PWM’d. Meaning its output is sliced on/off/on/off… in a way the led(s) only emits lights 50% or 30% or 1% - or whatever, of the time at a very fast rate so your eye does not see the blinking.
PWM - Pulse Width Modulation, is widely used to modulate things like light output, but on some lights/drivers the frequency is low enough it can be detected by the eye - and become annoying for some people.
The output of level 1/150 is almost entirely dependent on the hardware itself. It changes with emitter type, battery voltage, and a fair amount of per-light randomness. The range is generally about 0.05 to 0.30 lm though.
The D4 and FW3A also both only use 1x7135 for the moonlight.
However, the per light randomness is not entirely random. One known factor is that some 7135 chips do not work well if both the PWM frequency is high and the duty cycle is low.
The FW3A was requested specifically to use a known good 7135. As far as I understand it (a lot of this information is scattered across numerous threads that predate my time here, so I may be partially mistaken), Richard has not been able to consistently source those chips, so he tweaks the firmware on drivers he sells like the Moonlight special to match what the chips he gets can manage as their lowest stable output.
Sooooooooooooo, where can I order a programming clip for my precious? I’m not opposed to making one, but I’m getting lazy in my advanced age. I did try searching and found people mentioning ‘just order one’, but I couldn’t find where.
Also, should we start a list for TK’s special edition? I know I want a couple of purples. Someone tossed out 100 as a number to be made. I highly doubt that will be enough. My worry is that I’m on a trip where I only have internet every few days at best for another 3 weeks. If they come up and sell out before I can order one, I’m going to be seriously bummed.
I got my standard SOIC8 clip off Aliexpress, was only 2 or 3 bucks. There are different clips out there- mine is black. Have seen blue ones as well. Also check what cables you would like or need.
Easiest way of hooking up are Dupont cables F-F.
eBay/AliExpress for something like “6 arm helping hands” - got it a looong time ago now. I think it’s more for RC drones/copters, but having 6 arms is brilliant for holding everything down when working on it.
There are also some differences in firmware. Most moonlight-special drivers run something Bistro-like on tiny25 or tiny13, and they run moon mode at 13 to 17 kHz. This makes the code smaller and simpler, which is good… but it’s also extra-sensitive to changes in the underlying hardware. What’s bright on one light may not light up at all on another.
I did it differently in Anduril though. It underclocks the MCU at low modes, so moon runs at 4 kHz instead of 16 kHz. With each pulse being 4X as long, it varies far less with different hardware, different battery voltages, and different LED types. The slower speed would be annoying at higher brightness levels, but down at moon mode it’s not really visible or audible. And as a bonus, it also makes moon mode use a fraction as much power, so it can run at that level for about 3X as long.
So… less finicky about hardware changes and uses less power, but requires more complicated code.