Screen help, no backlight.

[thewise1]

Alright, about a week ago my screen was working fine. The led mod that is, but now I get zilch. The screen still works and everything. I hooked up the leds to an alternate power supply and tested it, works fine.

But every time I place a resistor on the 5 volt supply from the screen the leds refuse to light up. I've used 10 ohm like ben said and tried multiple resistors and I get zippo. I tested the 5 volt supply and it's working fine. NOW I'M REALLY CONFUSED!!!

The only thing that seems to be going wrong is the resistor. So any suggestions?

(keep in mind that the same setup was working perfectly a few days ago. It's also a 1w resistor but I don't think that has anything to do with it. Unless the leds need more current, which I highly doubt.) And I'm pretty sure I can't just hook it up straight to the 5 volt without a resistor.



EDIT: I had an idea but I need to know the max voltage for 3 mm leds. I was thinking I could run the leds straight off of the n64 controller 3.3 volts. They work fine at 3 volts. Already tested.

[thewise1]

C'mon now, I know that one of you has to know the max voltage for 3mm leds

[eurddrue]

Well, if it works for you go for it, but you might have something wired wrong in your screen because the LED mod has worked for most everybody else.

[thewise1]

I've already checked for shorts. everything used to be working fine, now it only works from an alternate powersupply.

Now I just want to know if 3.37 volts is too much for a 3mm led. I don't want to burn the out and have to led mod the screen all over again.

[marshallh]

Depends on the color. Blue/white leds (white is just blue with a yellow phospor) take a forward voltage of about 3.4v. So it should work.

[Kurt_]

Try a standard 1/4W or 1/8W resistor. It shouldn't matter but electronics are weird like that sometimes.

Also, what's your setup look like? Draw us a diagram.

[thewise1]

I've got 2 parallel led circuits coming off of the led I don't really have any ordinary 10 ohm leds, I'll see if I can find one of my old electronics.

[eurddrue]

I've got 2 parallel led circuits coming off of the led I don't really have any ordinary 10 ohm leds, I'll see if I can find one of my old electronics.

It's 10 ohm resistor, there's no such thing as a 10 ohm LED, maybe your a bit confuzzled.

[thewise1]

*FACEPALM* DOH!!! Lol, oops, wow I can't believe I just did that. lol 10 ohm led, lol Yeah you know I meant resistor.

[eurddrue]

*FACEPALM* DOH!!! Lol, oops, wow I can't believe I just did that. lol 10 ohm led, lol Yeah you know I meant resistor.

I thought you may have been confused on the parts

[thewise1]

Oh no I've caught on what the parts are called.

Ok, I got it fixed, all it was was it wasn't grounded.

Even though the screen was grounded, using the ground of the screen mobo didn't work. I tied the ground to the n64 ground and it works perfectly now.

I wonder though why the screen ground didn't work. So it works fine now with the 5 volt source and 10 ohm resistor.

[Kurt_]

What I said still applies, and a lesson is to be learned from this.

Electronics can be screwey like that sometimes.