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I need help with building a LED flashlight Answered

I have been building this 9volt LED flashlight but I used this LED resistor calculator and it came up with a diffrent resistor then was noted in the instructable, I bought these two leds at radio shack and a 150-Ohm 1/2 watt 5% tolerance resistor (Brown Green Brown Gold). The LED lights light up but they are not bright like a flashlight and can only be seen in the dark if you put your hand up close. Im wondering where I went wrong? This is my first time working with LEDs, Maybe the radioshack LED's are just crappy? Or do you think I got the wrong resistor?



Thanks guys, Any suggestions on where to get the best LED's?

If you're in Australia, or New Zealand, Jaycar electronics are a good retail outlet. Online, I've bought LEDs from ledsales.com.au, they were really good. Good prices, good service. Can't help you beyond that, sorry.

Those are low light LEDs and would work fine with only a couple of AAA batteries (They only require about 2.7 volts). If you want a bright flashlight, invest a little more change and use Ultrabright White LEDs.

I found a great white LED 'torch' that runs two white LEDs from a 9V battery at Andy's Solar Bugs. Sorry, I don't have a better address for his site. He uses a 75 Ohm resistor (Violet Green Black). To be on the safe side, if you're only using one LED, a 150 ohm resistor (Brown Green Brown) should work. All I can think of, other than that, is that the battery might be run down. Good luck, anyway.