10-ohm resistor and 3 LED's

collinE · Post by **collinE** » Thu Aug 07, 2008 9:38 am

Just bought some 10-ohm resistors and needed to know if mine are ok.

When I got home, I realized that mine are 1/4w 2% carbon film and Ben says to get ones that are 1/2w 5% carbon film. Are mine ok to use, and what will they do differently than Ben's?

Second, why did Ben use three LED's instead of an even four? Has anyone found that 4 is too much maybe?

Thanks!

Rekarp · Post by **Rekarp** » Thu Aug 07, 2008 10:17 am

I would use a 20ohm 1/2W resistor. At 10 ohms your are slightly overdriving the LEDs which shortens there lifespans. I don't know why he used 3 but I use 3 cause it gives plenty of light tho some beg to differ.

lovablechevy · Post by **lovablechevy** » Thu Aug 07, 2008 10:26 am

the number of leds you use is just preference. people on this site use 3, 4, 6, and even 8. increasing the number of leds changes what resistor to use.

collinE · Post by **collinE** » Thu Aug 07, 2008 5:20 pm

thanks for replying... buuut what will my resistors do differently than Ben's?

Post by **Skyone** » Thu Aug 07, 2008 5:35 pm

Nothing in terms of the specs you gave us. Depending on what your LEDs are rated to, they should suck up about .05-.1 watts of power, and 1/4W is still well over that. However, as Rekarp said, and depending on the rating of your LEDs again; 10 ohms might not be enough.

collinE · Post by **collinE** » Thu Aug 07, 2008 5:56 pm

ok I see. Although I looked again at the specs and it says 10K ohm. so I think the "k" means thousand.

sorry, guys. boy is my face is red.

Post by **Skyone** » Thu Aug 07, 2008 6:06 pm

Oh, well then you're screwed regardless.

palmertech · Post by **palmertech** » Thu Aug 07, 2008 9:27 pm

Lovablechevy: WHAT?! People have used 8? Link?

I ask because I thought I was the first one to do it, I was going to post pics today or tomorrow.

lovablechevy · Post by **lovablechevy** » Thu Aug 07, 2008 9:34 pm

palmertech wrote:Lovablechevy: WHAT?! People have used 8? Link?

I ask because I thought I was the first one to do it, I was going to post pics today or tomorrow.

you can thank Sharp Sapphire for beating you to it.

collinE · Post by **collinE** » Thu Aug 07, 2008 11:31 pm

does putting 8 LED's make it 8 times as bright or make each LED put out 1/8 the light? wouldn't be a bad idea if 8 kept it the same brightness, and just made the light more uniform.

lovablechevy · Post by **lovablechevy** » Fri Aug 08, 2008 7:13 am

collinE wrote:does putting 8 LED's make it 8 times as bright or make each LED put out 1/8 the light? wouldn't be a bad idea if 8 kept it the same brightness, and just made the light more uniform.

brighter. i've not used 8 leds, but i can tell you that 6 leds puts the brightness to about 90% of the original backlight brightness.

Website · Post by **Life of Brian** » Fri Aug 08, 2008 7:32 am

I always use 4. It's not quite as bright as the original backlight, but it looks fine to me. I suggest starting with a few and working your way up if you want more light. Really it's all personal preference. I use this website to calculate what value of resistor to use. Make sure to select series or parallel, depending on how you have it set up. I recommend parallel.

collinE · Post by **collinE** » Fri Aug 08, 2008 9:37 am

That's a really good website. I guess now I'll have to learn more about electronics.

I think I am going to just use 4. If I do a widescreen LCD then I'll use six.

I'm learning from doing. Let me tell you about how I just learned that soldering tip cleaner isn't the same thing as flux... the hard way. lol

Rekarp · Post by **Rekarp** » Fri Aug 08, 2008 9:43 am

collinE wrote: I'm learning from doing. Let me tell you about how I just learned that soldering tip cleaner isn't the same thing as flux... the hard way. lol

Best way to learn electronics and soldeing imo.

collinE · Post by **collinE** » Tue Aug 12, 2008 6:17 pm

I was going to start a new thread to show my LED positions, but that would have been a waste.

I put my LED's like Ben's, but with an extra one in the upper left.

I only put this up because I wanted to show the direction it was facing and see if this was how others did it. Also, where does everyone else put their LEDs for next time I mod a screen?

Also to show off this little man I made. He's saying "whoooaaa!"

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