Nice, a ~5K jump with that driver with 219C like I have. Thanks for doing this.
I did it too. Light output is brutal. Heat huge … :smiling_imp: Springs in the carrier warmed and lost contact … 
I thought maybe it was messing up my light box so i did a ceiling bounce before driver it got 1014lumens after 1635 lumens.
Hi guys! I have a question about my MF01 V1. On a turbo mode, one group of LEDs does not work. On fully charged batteries, everything is OK. But as soon as the voltage on them falls to 3.5 volts, then in turbo mode one group of LEDs does not shine. This problem was initially, as soon as I received a flashlight from Banggood. What do you think about it?
^The 3.5V is the resting voltage of the batteries, or the voltage under load?
If it is the resting voltage, then the voltage under load may already be under 3V, and then the LVP (low voltage protection) may have kicked in. As the driver is clearly divided in three sections, each driving 6 leds, the LVP may also be implemented for each section individually. Since the voltage readout of flashlight drivers is usually not very precise, one group may have shut-down already while the other two groups have a bit lower voltage threshold and may kick in later. This delay will be a bit extended even because one group already shut off, decreasing the battery load so that the battery voltage goes up somewhat again.
(I’m not a MF-01 owner btw)
3.5-3.6V - resting voltage of the batteries
I wrote in support of Banggood, and here’s what they said to me:
“we are so sorry we are not sure if this problem was caused by the man-made damage”
Strange support, however.
Thanks for the answer, djozz
All problems since Adam and Eve are man-made damage.
What batteries you’re using?
What is the status of breathing light on turbo? Red? Red blinking?
New 4*Sony VTC6 , оr new 4*Samsung Q30, or 4*LG HG2 - same result
Red
That is your issue, there is nothing wrong with the light. 3.5v is practically a dead battery. Under load it’s probably dropping to 2.8v. I’m surprised turbo would even turn on.
Using HKJ’s comparator @10A for 30Q and VTC6 results in about 3.2V~3.3V with 3.5V resting voltage. I’m not familiar with driver designs, but my guess is that LVP is built in the controller, so either all three drivers work, or all three quit, as the voltage is below a specific value.
My explanation was just a guess based on the symptom, if there’s just one MCU in this driver it makes no sense. 
Of course. What I wrote is also a guess. I have noticed that other people’s guesses in general lead to thinking about what exactly might be going on; and this eventually helps in better understanding what is happening inside a flashlight.
Does anyone else’s V1 light do this when the cells are at 3.5v and turbo is activated?
That should determine if it’s just his light or all of them.
You’re right! Now I measured the voltage under load (4*Sony VTC6), when one group of LEDs does not light up. In turbo mode this is 6.45V. This means that one battery gives ~ 3.2-3.3V.
I’ve never seen this info on his reviews. Then again, some of his tests are beyond my understanding. Can you show me where he tests a set resting voltage then applies a load on it?
Thanks
Jason, this an amazing tool. HKJ is boss alright.
http://lygte-info.dk/review/batteries2012/Common18650comparator.php
Just select for example Sony VTC6 on the left, and Samsung 30Q on the right. Then you can select discharge rates, for example 0.2A (~ resting voltage) and 10A.
Edit:
The “trick” is to realise that discharge rate at 0.2A is pretty much the same as resting voltage. Just look at 0.2A and 0.5A; the two lines are dang close to each other compared to 5A or 10A. So this means that resting voltage line is just a hair above 0.2A line.
Okay, that trick makes sense. I had not thought to do that.
[quote=JasonWW]
I will try to make video measurements in the near future.
You certainly don’t need to make a video for my sake.