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What kind of LEDs do I need for the LED-Wiz/Happ translucent buttons?
DaddyLongLegs:
Hey guys. I'm totally new here, and got most of my information for my new MAME cabinet by lurking here. I am now at a point where I'm too confused not to post.
For anyone that cares, I got an old Street Fighter 3 cab (the guy removed the game) for $350. Considering it has a working 25" standard res monitor, I thought that was a decent deal. (The only thing that sucks is I didn't realize until I got home the glass on the monitor is fairly heavily scratched, making playing games on it with flat colors/graphics very annoying as it gets a prism effect). Anyway, I am going to use MaLa and I bought a LED-Wiz because I heard I can have only the buttons the game uses light up. That sounds amazingly awesome to me.
I already bought my LED-Wiz, but the whole LED thing confuses me to death. I work for an electrical supply company and I would get LEDs at a big discount, so I'd rather go through my job, however in the gigantic book of 20,000 LEDs to choose from, I can't figure out exactly what type to pick out. I see tons of options like the mcd, forward current, wave length, typical mcd, forward voltage, test current, I could go on and on. I want to get 6 blue, 6 red, 6 green, and 6 yellow and use them all in my Happ translucents of the same color scheme. If someone could just help me out with that, I'd greatly appreciate it.
TOK:
You might get a lot of different suggestions, because there seems to be a lot of different ways to attain the same effect.
I went with 12v automotive LED's and powered them directly off the 12v rail of the PC power supply. I used Happ translucents, and like you, I got matching color LED's for the buttons to prevent any white light leakage (not even sure if that's a problem with white LED's).
Franco B:
Seeing as you are using an LED WIZ (good choice I may add :)), you want LEDs that you can power from a 5v supply (the LED-Wiz outputs 5v per output).
Basically you can use any LEDs that require a voltage of equal or less than 5v, if the voltage it requires is less than 5v you use resistors to lower the voltage. Typically you will be looking at a voltage between 2v and 4v.
I would go for the highest MCD you can find that you can get over all of the colours as you can always turn them down with the LED WIZ but you cant turn them up.. You will find that you can get brighter blues than you (generally) can get reds and yellows etc. Somewhere around 8000 MCD will be fine. Saying that I think the brightest yellows I could find when I was looking were 7000MCD.
I shouldnt worry about the current etc, if you choose an LED with those ratings you will find the current rating etc will be pretty standard 20-40mA.
If you are using very bright LEDs they tend to have a narrower viewing angle and so you may want to use something like GGGs diffuser discs.
The following pic is of some lit ball tops. the red, green and blue ball tops have a 8000MCD LED in, the yellow has a 7000MCD LED.
The following video is of an LED Wiz, clear 'Happ' translucent buttons, GGG diffuser discs and 13,000MCD ultrabright blue LEDs.
[youtube]http://www.youtube.com/watch?v=GwPkp8YLPV4[/youtube]
RandyT:
--- Quote from: TOK on July 15, 2008, 12:07:41 pm ---You might get a lot of different suggestions, because there seems to be a lot of different ways to attain the same effect.
--- End quote ---
There are a lot of different ways, but one shouldn't expect the "same effect". I purchased some of those "automotive" LEDs to test and they are very "run of the mill" superbrights with narrow view cones. They are costly and, IMHO, a poor lighting solution for buttons.
The best thing to do would be to do some research on how to obtain luminous flux specifications (calculators are available on the web) and shoot for high luminous flux levels and wide viewing angles. Narrow view cones create high-sounding MCD ratings that do not translate to especially good performance in this application. As Franco stated, diffuser discs can help here, but you may be surprised how much difference there is in luminous flux (actual light energy output) levels based on the angle of the LEDs.
If you are looking for vibrant light output in a well lighted room, you may find that the NovaGems (5x the output of a standard superbright) will be the only thing that will get you there. I don't like doing the plug as part of this, but I also want to make sure that the new folks who might have seen the videos on YouTube or elsewhere, understand what they were most likely looking at.
RandyT
DaddyLongLegs:
Thanks you so much for the incredibly helpful reply. I found 5mm, 5v LEDs with the resistor integrated. Does that mean I will not need a resistor then? Like it's built in?
I know about the NovaGems, they're very cool. It's just not worth the money for me because I can get the LEDs for near free, and the cherry switches too. Not to mention I just really love the HAPP concave translucents and I already have them. NovaGems are awesome, just a waste of money for me since I virtually have everything already.
Also, looking through the catalog, I see a lot of LEDs I can get "diffused". That would be best for this situation?
The reason I am so confused by all of this is because so many LEDs in this catalog don't have 5v for them. Hell, a lot of them don't mention the voltage at all. The ones that do (under "forward voltage type") are all numbers like 2 or 1.8 or 2.2. Or some are even more confusing and say: Vf @ If V, mA: 2.0(<3.0)@20 and basically my brain just explodes.