It's also expensive, and from what I see it only has two emitters not three (so I wonder how they can call it 3W...). But it would be interesting to compare the KD drop-in with the 556.
Considering Nichia is reportedly getting $223 for the quad LED and a custom high voltage driver would be needed to complete the build, this might be a good alternative.
I run mine off a 18650. here are some pics I took. it's really had to get accurate representatives since the camera picks up UV. I find that some bills will also show up but not all. The wavelength is too close to visable IMO. I'd like a 365nm emitter, but the good news it the output is pretty good as is. I'd hate to have it driven less.
Sorry about the links, I've never been on a site that used HTML for pics
[IM59-1.jpg[/IMG]
I ordered the 365nm 501B from Kaidomain. Now I wonder... is it useful to run it on two CR123A's? KD suggests it should work but I don't know about the driver.
I don't really feel like getting into Li-ion cells for just this one little-used light. Or is this light only useful if modded?
So I got the KAIdomain 501b light, but didn’t want to bother with Li-ion batteries.
I measured with a power supply, but it seemed that 2 x CR123A would lead to huge overcurrent.
So I bought SKU 128084 from Dealextreme - which the sent to me incredibly quickly BTW, and I started to work.
First, this is a pair of step-up regulators. You need to saw them apart as the PCB is not scored or anything.
I soldered the red and black wires to the inner spring and the outside of the PCB, respectively. I cut some PVC tubing to support the step-up PCB in place, and used a slightly larger PVC tube to keep my AA in the center of the light.
The 5/8” and 3/4” PVC tube work fine for this - the 3/4” fits nicely into the 501B holder, and the 5/8” fit on the back of the pill and hold the tiny DX pcb.
There was no need to bypass the “regulator” inside the 501B (is there any???) , The light works fine, it is pretty focused, and in the center it shows the same amount of light as the much less focused 395 nm 2-AA light I have. That is with the original glass in place.
The 365 nm light shows the red fibres in 20 euro notes, which my 395 nm light does not.
One thing that you need to watch out for is the lens in it. I got a 365nm light with apparently a normal lens… it does a wonderful job of blocking UV light. You really need a quartz lens to get the most out of these… probably no lens is even better.
And watch out for coated lenses. If the coating is not engineered for the short wavelength it can block UV light very effectively.
I removed the glass - thanks to my new two-step driver glued construction this is not harder than before - and tested.
There does not seem to be much difference. Placing and removing the glass does not make an immediate difference.
So I put the glass back. The ring that holds the glass in place has a little rim on the inside - keep that against the glass or the reflector will not fit.
I am still trying to understand the descriptions and capabilities of a UV LED. I am tempted to get a UV drop-in from MF or somewhere for my P60 hosts because I live in Arizona and dig hunting scorpions, and like the idea of having a powerful UV torch with more throw than the 7-LED cheapo 3x AAA crap light I got from Amazon for $6.
Can someone back up just a bit and explain some of the terminology in the thread and give me a hint on how to judge the usable distance a 18650 powered UV LED can throw? I assume it will be more than the three feet my cheapo light can do, but maybe I’m assuming too much?