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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,
Nick

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nickh83 (author)2007-01-01

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

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Wonko the sane (author)nickh832007-01-03

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.

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LasVegas (author)2007-01-01

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.

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Wonko the sane (author)2007-01-01

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.

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