My radio shack LEDs arent working!

[DaveSauce]

OK, so I'm making my own rheobus, right? And for some reason or another, my LEDs are doing nothing. Everything I have should be right....i've tried them facing both ways, and still nothing....heres a tiny diagram...forgive the crappyness of it, lol, I just drew it...

Anyway....I know it works with just the rheostat....the problem I think lies within the LED.....my voltmeter isn't fine enough to read it's resistance, so I cant tell if its working or not, lol.

 

[DaveSauce]

rarr, so now my LED is working, but my fans arent.....

ha....i think I just burned out my extra LED by touching it directly to the +12v molex...hehehehe. thats why i bought a 2 pack, heh.

 

[Diggrr]

Try it like this. The diode should be hooked the same place the fan is, so that the diode is lit when the fan is running. The way your schematic shows it, the fan is trying to draw power through the rheo on one side, and the resistors/diode on the other.

 

[DaveSauce]

ah, thats why your the expert...lol. Anyway, that will take a few minutes to work out...glad i'm using wires right now instead of solder....heh.

Just so I'm doing this right, the yellow/orange(+12v) wire from the PSU is the positive, and the black(gnd) is the negative, right? Should be, or else I should have burned out my other LED by now...

 

[Diggrr]

Just so I'm doing this right, the yellow/orange(+12v) wire from the PSU is the positive, and the black(gnd) is the negative, right?

Yup.

Hehe, I always do the same thing, twist the wires together to make sure, then solder after it all works.

 

[DaveSauce]

ahhhh success.

Thanks man, that helped me a whole lot...lol, I just hooked all my case fans up to the one rheostat, its fun, hehe. huge noise difference...heh.....ow, bad idea...i think my rheostat is about to melt, rofl. 6 fans at about 2.1 watts each....not a good thing...lol.

Oh yea, and is the 6.3 mcd on the box a brightness measure of the LED?

ummm....lemme think, any more questions....i guess not for now, heh.

Oh yea, do you know of any good places to get 100 ohm 5 watt single turn, possibly switching, rheostats?

 

[Diggrr]

mcd (millicandella's I believe) is a measure of brightness. The 6.3 would be perfect for on the front bezel so you're not blinded when the computer comes on. The big boys ($5 ones) are used for lighting stuff up inside the window (if ya got one).

As for the rheostats, I've never really hunted for them. I used to work for an electronics manufacturer, and would get all kinds of stuff for nothing because of a scratch here, short wire there etc...
When you make $15,000 laser's, the customer wants them perfect.