Sounds like its got a STAR firmware.
RMM, is there is connection between what you and vinh are doing?
The transistor mod took about 5 minutes worked great slipped on my meter and hit the wrong contact while checking current. Anyways, ordered some replacement transistors should have it up and running in a few days. I’m still a little puzzled as to why this transistor blew. I know I must have moved the probs on the dmm accidently and shorted but why would that burn up a resistor? I didn’t think the meter put out any power? Btw the light still worked but only on low mode with that transistor blown.
Sounds exactly like its got Werners UI, I use it on tons of lights, its free/open source FW so I doubt there is any connection…
Edit: an easy way to tell would be to ask him if its truly regated, the BLF drivers arnt regulated, I’m guessing he’s running a BLF XXdd driver in them with Werners UI, what gives it away is both buttons doing the same thing and the UI.
Yupp. Werners UI. STAR momentary, or whatever the latest tweak of Werners UI is called.
Vinh cant be using a BLF DD driver. That wont give 8A.
For most people having 5,8A regulated all day long from a buck driver and using normal cells is way better than getting 6A+ for a short amount of time with output dropping constantly from some "low capacity" high discharge cells in combination BLF DD type driver.
I believe RMM had a setup with some knuckleheads drivers in works and testing?? (Maybe thats wrong) He was working on a 8A TK61. He usually sells STAR momentary. So that`s why Im asking if there is a connection. If so, RMM can give us some details.
My plan have always been the HX-1175B since Im familiar with it and knows its good for whatever amps I want it to output. But Ive had really bad luck acquiring it.
Some months ago I ordered another Lustefire 3XU2 from WB Aliexpress. But they were sold out, so I was not able to get another driver from one.
My second attempt was buying them from an Aliexpress seller. I got the wrong ones. HX-1175C.
My third attempt ended up in a tracking number not working. Ordered 50 days ago. I have just had it reshipped. So, all good things are 4??
Thread about HX-1175B here.
Here you can see what HX-1175B can do in a ZY-T08 when its down adjusted to 6,5A.
Its nice to see people are planning different approaches. Im just curious if vinh and RMM are doing the same and have been working together.
About TK75, I might get back to making a thread about it some time in the (distant) future...
The driver’s not the limiting factor its the dedomed XM-L2, I have several and I’ve built quite a few more lights with a BLF17 and 20 dd’s that do well over 8A with other emitters (MT’s @ 8.4v, SST-90’s, multiple parallel XP-G2 & XM-L2 setups), my EDC runs at 8.4A and will do 13+ off a 25R (but the triple XP-G2 doesnt like that very much lol, anyway point being the BLF drivers can do well over 8A).
If he found a better way to keep it cool than a noctigon/sinkpad (like when people etch / mill a flat piece of copper down) I’m certain the BLFxxDD would be more than capable for the light.
You said it. With other emitters... You can get a BLF DD to supply 20A++ with the right emitters/battery combo, its irrelevant. But this is a TK61 thread. It uses an XM-L2. Vinh`s light uses an XM-L2. At 8A, 4,2V is required to the emitter. A BLF xxDD wont get near 8A peak even with freshly charged cells due to the voltage requirement.
Personally id rather have around 4,7A regulated with the stock UI (or 5,75A), than peak at 6A+ and output that will drop well below 4,7A in time (with BLF xxDD). No doubt that the BLF xxDD is capable, but I dont see it as an optimal solution for a TK61. Unless you want it to throw or have a pencil beam with other emitters.
Around 8A regulated to a single XM-L2, that is where the magic is IMO. I don't see how you can get close to that with a BLF xxDD driver.
But that's because even the best cell soldered direct to an XML2 with no driver or switch or springs won't be able to supply 8A with zero voltage sag.
The Vishay 70N02 FET is around only 4 milliohms, so the driver isn't what keeps them from being able to do those kind of numbers.
Exactly!
hmmm im far from expert, but doesn’t Fenix battery configuration put much less strain on the cells? i think 8A is not problem at all. I was told, even at 4.7A its like 2.2A per cell, so 8A should be around 4A per cell?
With multiple cells and higher voltage and a buck driver 8 amps or more isn't a problem. Well, if the driver is built to allow that kind of current. A buck driver converts the excess voltage into amperage.
The limitation with a direct drive driver isn't anything to do with the driver, but rather the lack of headroom between the input voltage and output voltage.
Carried my TK61 doing 406.25Kcd and that was enough to shine across the Mississippi River at Vicksburg. 
Found new drivers had arrived while I was gone, so will be looking at bumping power…
Sorting things, will be back with a pic or 2
The old gent that was hanging out at the lookout, watching barges slide down the river as he’d done most of his life first told me it was impossible “Son, that there River is a MILE wide!”, then shook his head in disbelief at what he was seeing. (It’s not a mile wide at this point “only 1072M”, but is in other places) When told this power level would end up nearly doubled, he was incredulous. Love playing with lights like these around non-flashaholics.
Finished up my first mod on my tk-61 did a gasoline de-dome and resistor mod. Everything went great super bright and an amazing throw. Never would have known about modding this light if it wasnt for blf. Just want to say thanks to everybody wo shared information with me.
Hi guys, some tips how to center the emitter/reflector on the TK61? i heard its very hard, and if the led is not perfectly centered you could lose like 15% of the CD, is this true? Sad
It’s a wonderful feeling when you amaze someone like this. Showing someone who’s used to Energizer lights which have one LED and a little aspheric lens a light pushing 1km in throw always blows people’s minds.
It makes my hair tingle with joy whenever I read this. (Okay, I’m weird.) XD
Did you end up leaving the dome on? Any idea of kcd and lumens with dome?
At 5.75A with dome ON it gets 330-350kcd at around 1900 lumens.
So how does 350cd translate into meters?
My guess is 25% bump from stock? or around ~ 1050 meters?
Just note that it’s 350,000 cd, not 350cd
to 0.25lux it’s square root of 350k*4
= 1183 meters.
Realistically you won’t see things at 0.25lux though… More likely 1 lux which is half the distance.
Thank you. Useful light would be around 1/2 of that i guess? so 600 meters should be a good distance?