Identifying Mystery LEDs?

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Tchail
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Identifying Mystery LEDs?

Post by Tchail »

I recently found a small bag with 50 3mm LEDs when I was digging through a closet.

They're water-clear, so I don't know know what color they are. I know that red/yellow LEDs typically are 2.2V, while white LEDs are 3.3V.

Any suggestions on how I can tell what they are?

(And yes, I do have a digital multimeter...)
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brt
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Re: Identifying Mystery LEDs?

Post by brt »

probably an easier way with your meter than this, but hook them up to a variable resistor/ trim pot and gradually turn up the juice until the LED lights up.
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Ant
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Re: Identifying Mystery LEDs?

Post by Ant »

Easiest way is with a LED tester

https://www.ebay.co.uk/itm/High-Quality ... 0505.m3226

Failing that, just use a battery source 3 - 9v and a resistor around 1k - this will give you enough current to light any type enough to see the colour, but not enough to burn it out.

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EVApodman
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Re: Identifying Mystery LEDs?

Post by EVApodman »

A standard meter set on OHMs will supply about 1 volt of power which is sufficient to light the LED without a resistor to determine the color. If it doesn't light reverse the meter leads.
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Tchail
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Re: Identifying Mystery LEDs?

Post by Tchail »

Cool!

Thanks!
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Re: Identifying Mystery LEDs?

Post by TurkeyVolumeGuessingMan »

If you don't have an LED tester, you can just use a CR2032 battery. Just slide it between the prongs and a 3mm LED ought to light up.
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