Fenix TK61 teardown and mod thread

So I said “seems” :wink: If you corrected the focus is ok…just wanted to collaborate.

I thought it should look like that :

If I’d pulled the camera back to about 3’, or the focus point, it would look similar to that.

That picture was taken to show the reflector cut out to accept the 20mm star. And of course, is actually the Fenix TK61 that this thread is about. :wink:

Taken from almost 7’ above the light…

Take a picture at that distance, and it looks very similar to your photo sorry! :frowning:

Of course, is thread of Fenix TK61 :~

See how that warp in the outer edge of the lens remains consistent? I believe this is what is keeping this light from being far up into the 600Kcd territory.

Also notice how the reflector has an appearance like it’s Orange Peel? This is a smooth reflector. These are reasons why I dislike plastic reflectors.

I also think that it should be within that territory…. I think the poor finish of this reflector is the cause, you did something? try to clean it? does not look like std TK61 reflectors

No, I didn’t do anything to it, other than cut the bottom out.

Ordinarily if an aluminum reflector has ripples or lines in it I’ll hand polish it out. I’ve had great success with this. Again though, can’t do that with a plastic reflector. Beats me. I’m planning to search for a good reflector that will fit in here and see if I can get a better result.

Anybody know where a TK61 reflector can be found? Or one from another light that will fit this one?

Hi guys, did anyone measure,

Stock TK61, dedome only, current bump + dedome, how much cd does it increase with current, is it linear or at least close to it? based on this, it should be 1700 lumens or lets say 1650, does this means around 60% throw increase? thanks.

Vihn has some serious update with v2.0
I would like to see the driver he used. TK61vn V2 - Throw King +740K Lux ;-) | Candle Power Flashlight Forum)

Ill put my money on the HX-1175B from RMM (Not official yet).

It that is the case, its the driver I mentioned early in this thread a few months ago. ;)

(but with some tweaks that have cost RMM a ton of emitters to figure out)

Shut up and take my money.

a question:

why do you try to replace a p-channel transistor c01c by an n-channel transistor (70N02) ?
i mean it can not function as.

Different polarities, one triggers with pulling the gate (or base) to ground, the other applying a voltage

alot of reading…but hope that helps

Welcome to the forum phil76.

It was just a quick test I did for RMM.

Latest and greatest driver "mod" for the TK61 might end up being this.

Just an FYI- I’ve already corrected the issue tterev3 pointed out in the .sch, just need to fix the board (I added a gate resistor, series / limit resistor (or whatever the name for that would be) and BJT to facilitate the P-FET shutting down all the way.
This is high on my priority list but not at the top and I till I can secure a TK61 for testing I seem to be lacking motivation with all the other crap I have to do (hey I just posted the project 3 days ago, cut me some slack lol).

My TK61 arrived today. Batteries took a couple of hours to come up to 4.2.
For my short available range it lights up well. This weekend I’ll give it some distance over water.


Voltage regulator fried, I think it is that same type like the regulator near, type “C01C”. Can anyone help checking his tk61’s driver?
Before I removed it only lowest mode was working, after removing flashlight is dead (pretty normal?).
I found some components in aliexpress and I plan to buy some. If I bridge the spot over there, what will be the results? Do you have any idea if I can find one of these regulators in other drivers?

Does this RaceR86 pic answer your question? Appears to be some type of FET you are pointing at.

Yes and thank you.
I destroyed Q4.

I’m sorry for what happened, I see also the encapsulated coil it’s broken :~