SmallSun ZY-T08 driver mod

Just a small report on my driver mod of the T08:
I put an NANJG105C 3.5A (10*AMC7135) in, which I fortunately had lying around for another mod.
I kept the old driver as contact plate.

Stock: measured 2A (varying), 660lm, 33kcd, 360m
NANJG 3.5A: (current not tested), 940lm, 50kcd, 450m - and whatever modes I like (custom firmware) :slight_smile:

Maybe I can sell my STL-V2 now :slight_smile:

Does it throw better than a STL-V2?

No, same.

how’s with the heating?

Just got my T08 today from FastTech. I'll be doing the same as the doc, but more amps and XM-L2 U2 1C on a SinkPAD, and see if I can add some copper somehow . Think I'll do some battery tests first on my 7G9 to see how 2 batteries in parallel perform with the XM-L2/SinkPAD combo.

I think the doc has the right idea for this light - it's perfect for a regulated high powered Nanjg, and hoping the 2 batteries will help with the Vf gains. Got some Pana PD's and Sanyo 2600's on the way, so maybe their lower resistance will help with this setup.

I am planning on doing the same mod with the xm-l2, nanjg105c and a few 7135 chips added, should be a nice upgrade.

Regarding the driver swap, will I need to remove all of the chips from the original driver to use it as just the contact plate?

I did a resistor mod for now. At 3.2A, heat is not an issue.
If you plan to push it, check the star-to-pill contact. I lapped my pill a bit as it seems high in the center.
I have bigger plans for my T08 :wink:

Funny this thread started at the right time.

My T08 arrived 2 days ago and I will try a resistor mod using 2*0.22ohm resistors and XM-L2 U2 on a Sinkpad (non-copper version).
Plus I planed to switch the cables for thicker ones.

Honestly I don’t know if 2 resistors will push the current higher, I’m a total noob in these electrical stuff.

nikanon, the two 0.22 resistors added to the ones there will probably put the current just under 3 Amps. I added a 0.082 and got 3.2A.
Beefier emitter wiring should help. Don’t forget to add copper braid or soft stranded wire to the springs in the tail cap.

Yes, I noticed the same thing - a flat copper disc actually teeter-totters on the bump, bad sign, so I'll do my usual sanding from 200 grit up to 2500.

I tore it down last night after doing benchmark measurements on the stock light. I'm using an extra UCL/p lens, was bought for an HD 2010 - already have one in an HD 2010 and saw a good improvement there, only a minor improvement in the stock T08. Going from a 3.0mm lens to a 2.0mm saves clearance, and looks like a 3/4" 18 gauge copper disc will fit under the SinkPAD, so I'm going to try that - hope I can solder the disc under the SinkPAD using solder paste and a frying pan, like reflowing - not sure if a big iron tip would work that well. The pill, though cavernous, just might have to be skipped because unsure how to fill it with anything I got that would help.

Blazar - Yes, Im planning on stripping all components off. You want to make sure there's nothing that could be a drain on power.

Stock measurements, 2 fresh Pana 3100 unprotected batteries - 2.1A:

lumens: 656 at start, 639 at 30 secs, w/UCLp lens: 673 at start, 653 at 30 secs, 48 kcd measured at 4.3 meters (didn't measure throw with stock lens)

I think the throw number is impressive for a 2.1A tailcap measurement, so hoping to get good results. I got great results from a HD2010 upgrade that's doing over 1,300 lumens and 91 kcd on an XM-L2 U2 1C, and these lights are very similar in reflectors and overall size/weight, but like the 2 parallel battery setup better. Plastic reflector and alum bezel (not SS) are disappointments though.

Also I did 1, 2, and 3 parallel battery tests in my 7G9 running an XM-L2 U2/SinkPAD and yes, adding batteries does produce higher amps with Panasonic 3100 unprots (1 battery: 2.3A at switch, 2 batteries: 3.25A at switch, 2 batteries taped: 3.7A w/no tailcap). However, it looks like one AW IMR 2000 beats the 2 Panasonics, so battery resistance is important. The 7G9 has a 4.2A configured Nanjg, but best I could do was 4.0A through the switch with the 3 Panasonics. Actually I got 4.15A using the same 3 batteries with no tailcap, so I'm getting a significant loss thru that tail cap (springs, switch assembly, etc.). I got supposedly lower resistance batteries coming soon (Sanyo 2600, Pana PD's, etc.) so I'll see if they help. Apparently it's a struggle with resistance through the batteries and the battery - path with driving this setup on high amps... I'm not sure what can be concluded here for certain because of the limited types of batteries used and apparent high resistance in the 7G9 tailcap assembly.

I got a Small Sun ZY-T08 without LED incoming. Planing to use thicker wires and put in a dedomed XM-L2 on copper. I also got some 0.22 resistors here.
And thats where my knowlege ends.

What do I have to do to increase the current?
Where to solder the resistor(s )?
Anybody got a picture?


Check my review thread for this light. There’s a pic or two, and a few comments from those that have done it. :beer:

Have a problem. Need a new LED + star for the small sun.
Only have a 16mm copperstar with xml2 here, but it does not fit.

Any idea? Will a 20mm star fit?


By not fitting, do you mean it's too small? If so, it shouldn't be a problem, may take some playing with, but if you use thermal grease and center by hand/eye, then mount the reflector - you should be able to get it centered ok, with maybe some retries and fiddling. The reflector should apply enough force to secure the copper star down. I've only used 20mm stars on a T08 - better clearance for the wire solder connections, but I would think you could still get a 16mm to work, but 22 gauge wire may be more difficult - better to go with something thinner.

The problem is, that the reflector presses on the soldering of the wire. The LED is to deep then.
So I need a bigger star that the soldering is not directly under the reflector.


Ooops - yes - 16mm star does have issues. I always use 20's for this light, not sure though if the copper ones need trimming - they are easy to sand or grind down though - I've done that a ton of times.

Anyone considering a dedome should be careful to avoid what I ended up with. I simply removed the star from the host while leaving the wires attached. This gave me about 1 inch of space between dangling star and body where I could dip the star in gasoline and and not have the body make contact. Well my device for holding the light up at the perfect height failed and the body came in contact. Even though the side switch rubber cover was not in direct contact it expanded and ripped, and who knows what internal damage I caused. Also the light unscrews at a previously fixed joint. Dedome was perfect and light still functions, however.

Oops I thought this thread was about the zy-t13