17mm for direct install into lights without having to be piggybacked (yes I forgot to bStop the bottom batt+ pad but thats where the spring would go). This one has the correct size MCU pad (for the 85-20SU) and 2502 FET’s!
There are several known problems (and probably several more I dont yet know about) but I’m working on it. just wanted to show off for now. The bank of resistors at the top are limit resistors (right most is C1).
The green and blue will be allright, the red @ 2v is as issue tho I’m running a RGB light with XP-E2’s now and it works allright, the red is by far the brightest. Thats what the addition of the limit resistors are for on the 17, I’m gonna start from scratch and do another 22 tomorrow.
I’m figuring I’ll use one or two 1206 pad per channel and I can stack them on top of each other if more are needed.
These are XP-E2’s at ~1.2A each (that’ll soon be raised to 2.4A) the strobe it 19hz however each color only pulses at 1/3 that rate cause it does RGBRGBRGB (the iphone camera has no chance, video just doesn’t do it justice)
Wooo doggies! ;D
If only i can see it in person! A guy on the “other forum” posted about strobe. Study of Tactical Strobe
Most important part:
Having said that, the right strobe needs some clear specs.
We found, that with a slow or changing strobe, the opponent was able to (slowly) move their hands without being detected. The strobe is still very disorienting from the slower 5hz to 12hz and even higher, but the effect seems to get less when going much faster than 24hz.
We worked the strobe up to around 18hz to 20hz and that problem (noticing movements)was tackled. At 18hz to 20hz, the strobe was still extremely disorientating and the opponent could not move a finger without detection.
So, strobes at 8hz, 10hz, 12hz etc ARE very disorienting, but could have unwanted negative side effects for the LEO.
Thats why we chose for the 18hz to 20hz, less unwanted side effects.
Do you think you can do a “no delay strobe” as in, there is no time delay between the color switching? maybe that could be pretty cool.
About the values of the current limiting resistors on the little rgb(w) board: perhaps it is best to tune it while measuring output current. It will be dependant on the used battery and other resistances in the used host. I'd say, better be a bit on the low side with the resistors , then it still gives good output with lesser hosts/batteries. It looks like 2A is perfect for all xpe2's (and xml-colour dies) if on copper/Sinkpad, and it seems that up to 3A is still handled fine.
Yes 19*Hz*, sorry bout the multiple typo’s, my phone insists on changing Hz to kHz every time I type it, it must assume nothing runs at JUST Hz anymore… I wish I have a video camera that could show it, its intense to say the least.
As for the driver, let’s just say its proprietary lol…
That thread you linked is the exact reason 19hz was choose. BTW a new driver is in development for the current light (with the assistance of my buddy tterev3) that will do even more (that’s why the drivers in this thread use the 8k tiny85 so I can program it AND have lots of room to play with) but the new one for the tk45 will be based on a PIC MCU to fit even more programming for fancy stuff.
I love you guys but please don’t expect much info on it, I’ll show it off sure but its one light I intent to keep the spec’s / production info on hush hush, atleast for awhile.
What do you guys think about using a Zener diode to limit the voltage to the red emitter, could a ~2.2v Zener be found that could handle ~2.44-2.6A being passed threw it?
Why would a Zener be better than a cheapo black barrel silicon diode, or a silicon diode in one of those heatsinkable packages that you see FETs in? Do you just need something that will drop a few volts, may be inefficient, but may be easiest.
Don’t know enough about FET’s to be be technically accurate enough for the discussion
I wonder if you could calibrate different gauge wires, as in on the red one, use a 30 ga wire instead of a 22 ga and see if it restricts current flow enough not to overdrive the red led
In a fet driver with a led that can not have the full current the question is just: where do you want to burn the power, and perhaps a resistor (near the edge of the board) is a better place than a fet or a wire?