The SRK can still awe even the best lights after a little mods.
where did you get your resistors from ? i have 3 SRKs i like to mod in a similar way.
I finally got some spares to experiment on, it's been a while since I messed with one. Now, what's the reasoning for changing the tiny little '153' resistors, instead of just going straight for the sense resistors?
On a bench test (only using one LED on one channel, with all 3 it may do lower numbers than this), in stock form it does 2.85A. R010 jumpered with my Precision Lab-Grade Calibrated Tweezers™ gives 3.60A. And jumpered with a flat blade screwdriver gives 4.18A.
I didn't have great results before with changing the little resistors. I couldn't get even close to where I wanted it, ended up far short of 4A each. What gives? Has anybody else adjusted it with the big R010s instead of the little ones?
edit: Just noticed they're not all R010s in all 3 locations on the 3 drivers - one has a R100, other two have a R110 each. So they are being used to balance the output among the 3 channels.
EDITED: I don’t remember making this post and am confused by what is typed so strikethrough. BTW never accidently or otherwise take more Ambien then prescribed. 
I did read the purpose of the smaller value resistors(R100,R010,R110) you speak of are to balance the circuits. I have not confirmed the purpose of those resistors but you are going down the right road. looking forward to your results
Yes we can change those sense resistors to increase drive current. but its not easy to find these mili-ohm resistors.
to increase current to 3A, sense resistor should be 0.0066 ohm (6.6 mili ohm). A 22 mili-ohm resistor parallel with exiting resistor will do.
Balance resistors: yes it for balance 3 channel but still 3 channel unbalanced. there is a layout track issue. Middle driver has lowest current. left one working its rated current. right one little reduced.
check early post of this topic to see that issue and fix for it.
Ok, so I’ve got myself a FandyFire UV-S5 that I intend to mod with a custom interface that I’ve been working on. But… I can’t get the bloody thing open. I’ve tried unscrewing the crenelated bezel to get to the reflector but that seems to be glued down? I tried gently gripping the reflector and giving it a twist but I was afraid I would scratch it up.
I read somewhere in this thread that people pushed the driver out through the switch opening so I removed the switch (and found out that it uses active high, for my custom board I assumed active low 
). Looking through the hole I can’t really see a spot where I would dare put any pressure. I fear I’ll slip as it’s hard to get a good fulcrum going.
Am I just being too gentle or, more likely, just being stupid?
The reflector is bolted to the pill with a single screw in the center, can't get to that screw until the driver is out.
Make a hockey-stick shaped tool to go in through the switch hole. It needs to be pretty seriously stiff metal so coathanger won't do it, needs to be more along the lines of welding filler rod. Round off the tip that touches the driver so it's nice and smooth, it won't hurt anything. Feel around and you should be able to tell if you're on the PCB or something else. Then just lever it out.
Some are only pressed in, a few I have seen have a clear plastic-like glue in two spots on opposite sides. They can be pretty tight but if you're pressing on the PCB it won't break anything before it pops loose.
Thanks for that. I’ll see if I can dig up an old hockey stick around here and give it another go 
edit: Found a pair of pliers with a curved tip. I put a bit of heatshrink tubing on the tip for protection and stuck it in there. It didn’t take much pressure at all before it popped out. Thanks again
I had to try another method which might work for some tough drivers. First I soldered a 16awg wire to the visible side of the driver then used the hockey stick method while I pulled on the wire.
btw: It looks like all the FandyFire UV-S5’s are being glued in place. Have you been able to remove your tail cap?
Fortunately the hockey stick method worked fine for me (see edit above).
As for the tail cap, I hadn’t planned on removing it but I gave it a try. My hands weren’t strong to get it done on their own and unfortunately I don’t have any strap wrenches. Is there any specific reason you want to remove it?
Yes...
See the four bare aluminum areas? Stock, those are anodized, so all the current has to go through the little M2.5 screws. And the screws are very often found to be loose once the tailcap can be removed.
In the pic I've scraped away the anodizing so the plate itself can carry the current independent of the screw threads.
Aah, gotcha. I guess I’ll have to look into that myself then. Maybe I can improvise a strap wrench with an old belt or something. I might also bump up the wire thickness a bit, they looked a bit weak sauce to me.
Good luck with getting the tail cap off. I have tried heat, cold, jar openers and strap wrenches with no luck. I don’t want to be a wet rag but the only SRK I seen where someone got the tail cap off the barrel was destroyed in the process. I think this only applies to the fancyfire SRK’s currently being sold. I don’t know how long they have been securing them like that.
EDIT: I received my second “fancyfire” SRK today and it is not glued together.
About midway down this page is an image of a destroyed SRK complete with glue on the tail cap threads. UV-S5(SRK) tailcap removal?!
resistor mod + button mod done, but how i change UI? ATtiny maybe?
Very nice first post Jeepster! Yup, seems like going with JANJG 105C master/slave/slave is a good way to go. Something I've wanted to do for a while but just haven't had time.
I was pulled off of getting these things built in quantuty in order to do some high-paying real world work… hope to get back on this driver real soon now… still haven’t heard back from Pilot about having PCBs made.
Nice switch mod :)
What switch is that? What did you need to do to make it fit?
Looks like a standard “vandal proof” switch. Here’s a random one of many: http://www.ebay.com/itm/Red-LED-Light-24V-16mm-SPDT-Stainless-Steel-Round-Momentary-Push-Button-Switch-/300824175675?pt=AU_B_I_Electrical_Test_Equipment&hash=item460a84a43b
They come in all kinds of sizes, colours and switch configs.
Hi Jeepster and welcome to the forum. Don't know if you saw this, but Post 97 has some info that would enable one to wire in a Attiny. There is an example of one done at Post 100. I've been thinking of trying it out on a SRK and on a TR-3T6.
I don't know if anyone's exposed the board layout like this before, with my luck it was already done 3 years ago...
There are some missing/damaged traces at the center left, shouldn't be an issue since the other two sectors are the same components just arranged differently. Red line is the path of the tiny little trace on the opposite side that runs between the + and - planes.