Fenix TK35 UE – Ultimate Edition MT-G2 - 'Compact Review' (2x 18650, 4x CR123)

subwoofer

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Though not the first to use a side-by-side 2x 18650 cell configuration, what Fenix did with the TK35 was to make one of the most compact lights in this category. Very well liked in its stock form, the TK35 has now been upgraded to the 'Ultimate Edition' on test here. Fenix have used the monster MT-G2 LED in neutral white giving you a powerful pocket floodlight.

Author's note: due to the general tendency for reviews to become ever longer, this review is presented in a different format to my previous ones, with all but two images being animated to attempt to reduce excessive scrolling. You may need to wait for the images to load fully.

A quick look round the TK35UE

TK35UE_2.gif


The monster MT-G2 LED

TK35UE_MT-G2_2.gif



Taking a more detailed look:

The photos here show; the packaging, box contents, holster, disassembled light, power and mode switches, threads, contacts in the head and on the battery holder, some details of the battery holder and the big MT-G2 LED.

TK35UE_overview3.gif



Looking around the holster, it has a hanging loop and belt loop. Unlike most holsters, there is no flap, but instead a Velcro strap that is used to secure the TK35 UE in the holster.

TK35UE_Holster_1.gif



The beam

The beam is neutral white (the tint is not well represented here), and nicely floody thanks to the large emitter and orange peel reflector.

The standard TK35 was considered to have a beam somewhere between the TK41 and TK45. The TK35 UE has more flood than the TK45 and over twice as bright.

A control shot of the TK41 (XM-L version) is included for comparison.

Beamshots.gif



Modes and User Interface:

There are 4 steady white output levels (Low, Medium, High and Turbo), and two flashing modes (SOS and strobe). The TK35UE's main power switch is a forward-clicky.

To access the flashing modes, press and hold the mode switch. To change flashing mode, again press and hold the mode switch. Switching off the light or a single click of the mode switch reverts to steady output. The last used steady output mode is remembered.


Batteries and output:

The TK35UE will run on 2x 18650 (in 2S1P) or 4x CR123 (in 4S1P).

Keeping this test 100% Fenix, the TK35UE was powered using the Fenix ARB-L2S 3400mAh 18650 protected cells charged with a Fenix ARE-C2 charger.

20_ARE-C2_readytogo.jpg


To measure actual output, I built an integrating sphere. See here for more detail. The sensor registers visible light only (so Infra-Red and Ultra-Violet will not be measured).

Please note, all quoted lumen figures are from a DIY integrating sphere, and according to ANSI standards. Although every effort is made to give as accurate a result as possible, they should be taken as an estimate only. The results can be used to compare outputs in this review and others I have published.

Fenix TK35UE using ARB-L2S 3400mAh 18650I.S. measured ANSI output LumensPWM frequency or Strobe frequency (Hz)
Turbo18490
High7960
Medium2700
Low330

Store frequency alternates between 15.3Hz and 6.6 Hz

This runtime trace is on Turbo output mode (reset at every step down) and using 2x Fenix ARB-L2S 3400mAh 18650 cells.

TK35UE_runtime_Turbo_ARB-L2S.jpg



Wrapping-up

Fenix really have made the most of the 2x 18650 side-by-side format of the TK35 by equipping it with an LED that can use all the available power. As you can see in the runtime trace, when the TK35 UE is fitted with quality high-capacity cells, it can maintain an output over 1700lm for 35 minutes! An hour after fist switching into Turbo, the output is still 1300lm. For a light this compact, the performance is fantastic, and this is indeed the 'Ultimate' TK35.

When moving up from a single 18650 light and its performance limits, the TK35 UE rewards you with double the output but without doubling the length. In fact it is not that much bigger than some single 18650 lights, and the rectangular battery tube is very comfortable to hold.

As with most Fenix lights there is the dreaded step-down from Turbo to High after 5 minutes of runtime. However, in this instance I will forgive Fenix, as a light this compact pushing out over 1800lm does get hot quite quickly. I would agree that the user should have to reactivate Turbo if they want it.

The MT-G2 LED is a large die size, and therefore ideally suited to a flood beam. In my opinion, the requirement for throw is much more limited than for flood/area lighting, as the majority of people want to see what they are doing or light up an entire room or the area they are working in. This makes the TK35 UE an excellent general purpose light with a fantastic neutral white 1800lm to call upon when needed.


SubwooferLogo800.jpg

Fenix TK35UE test sample provided by Fenix for review.
 
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Reserved for updates...

Following some discussion in the TK32 review thread:

http://www.candlepowerforums.com/vb...-Compact-Review-(1x18650-2xCR123-or-2xRCR123)

I have revisited the TK35UE's battery carrier and control circuits. There is still more to understand about the battery carrier of the TK35UE, but the following has been measured:

The carrier's output terminals read 0V when the main power switch is off.
There is no parasitic drain present WITHIN the carrier, so the main power switch disconnects the cells from any circuitry within the carrier.
Using an oscilloscope, it appears that when the mode switch is pressed that a 500kHz signal is present on the output voltage. (However as the measurement is being taken effectively 'open circuit' as the carrier is not connected to the head, this may not be entirely accurate).
Output voltage of the carrier is 6.87V even though both cells are at 4.15V.
 
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Fantastic review subwoofer:twothumbs loving the animated pics:twothumbs must admit i get more tempted by the day with this light...........
 
Nice light with nice LED. I have the older Fenix LD41 (XM-L U2) and I find the grip nice as well. But I think I will save my budget for something else instead. Was thinking of getting the Zebralight H52w (1xAA/14500) that just arrived at my local store instead. I am actually looking for a light with a really warm tint which will be my first one. (The Surefire G2X Pro I have uses the Nichia LED which is not very warm)
 
Consider the ET MX25L3 Compact. One option is six Nichia emitters, 4500K, 1800 Lumens and 317m throw. I almost tempted myself.
 
Does anyone use 4.35v cells for this thing? I'm thinking of ordering some of the LG's for longer turbo times plus pink is cool. I see from the manual it supports 4xCR123 so I think the driver would be fine.
 
Does anyone use 4.35v cells for this thing? I'm thinking of ordering some of the LG's for longer turbo times plus pink is cool. I see from the manual it supports 4xCR123 so I think the driver would be fine.

I suspect it would be fine too to use these, but am not convinced how much more full output Turbo this would give you. The runtime trace in the review is with the Fenix 3400mAh cells.
 
Thinking to pull the trigger on this one.:twothumbs

Well.....I thought....then.....DID IT!
Mine should be in my hands by next Wednesday (5/28)!!!!:thumbsup:
Got some Panny 3400mAh NCR18650B's "warmed up in the bullpen....."!!:D
GREAT review, subwoofer!!:)
Keep a SHINE ON!
UPDATE: Order Status now shows my TK35UE is "BACKORDERED"!!!!:mad: The site had them listed "IN STOCK" when I ordered!!!
(Vendor's name withheld, pending final outcome......!!!)
 
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I suspect it would be fine too to use these, but am not convinced how much more full output Turbo this would give you. The runtime trace in the review is with the Fenix 3400mAh cells.
If the higher voltage could squeeze another 10 minutes of full turbo I think it'd be worth it at the expense of a little bit of runtime at the tail end. More than worth it since I can get these cells for much cheaper than any Panasonic 3400s. Plus I dig the pink.
 
If the higher voltage could squeeze another 10 minutes of full turbo I think it'd be worth it at the expense of a little bit of runtime at the tail end. More than worth it since I can get these cells for much cheaper than any Panasonic 3400s. Plus I dig the pink.

It is a small light with only two cells. The timed step down won't change. It is there to prevent overheating as well to preserve the battery. If you want full lumens from the MT-G2 then look at the MX25L3 which is still very compact. The TN35 and Niwalker Vostro BK-FA02 are even bigger. You need size to dissipate heat and batteries for run time.
 
Thanks for putting this review together subwoofer! I really like the form of this light though I'd prefer more throw. Is the LED easy to get at in this light? I was thinking of getting one and dedoming it if it was easy to get at...

Second slightly off topic question on the charger in your picture. I got that same charger with the hopes of consolidating many of my chargers excited it could do NiMh "C" batteries which I go thru quickly for my varapower. Only problem is C batteries aren't close to fitting in mine - do they fit in yours? I've got the tenergy 5,000 mamps FWIW...
 
Very cool light; thank you for the review! The comparison in the backyard really blew me away. :)
 
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