5mm High-Brightness White LED (2-Pack)

Comments about RadioShack 5mm High-Brightness White LED (2-Pack):

Used this led in a home made optical tester( Foucault) with a variable constant current source,
1 to 23 ma and a drafting film for a smooth light diffuser.This led delivers more than enough intensity for this application! Works Great !

Comments about RadioShack 5mm High-Brightness White LED (2-Pack):

We have evaluated the review from Erik of Seattle. He is correct - This item only has two leads. It was likely the mirrored-effect in the product image that made it seem as though there were three leads. We have updated the image, removing the mirrored-effect from the lead area. We apologize for any confusion and inconvenience.

Note: A rating is required to submit a review. RadioShack chose the 3-star middle rating, because we felt we should remain neutral. This rating does *not* indicate our assessment of the product's value and reliability.

Comments about RadioShack 5mm High-Brightness White LED (2-Pack):

The Radio Shack picture of this LED is incorrect. The LED only has 2 leads, not three.

Comments about RadioShack 5mm High-Brightness White LED (2-Pack):

I'm using a bunch of these to replace some old fuse lamps in a 1970s stereo receiver. I ran each LED in series with a 1k Ohm 1/2 watt resistor and a 24V DC source. Very bright, runs cool. 21 mA and 3.25V across the resistor. I'd buy these again!

Comments about RadioShack 5mm High-Brightness White LED (2-Pack):

Lou: you're overdriving it. White LEDs are a perversion of Blue LEDs. If you run them too hot they show their roots. Back off your current.

skeeter_mcbee: Similar problem to Lou, but from the opposite direction. LEDs are Current Driven devices. There is a threshold. If you're just barely driving it on, then any resistance will shut it off. Also, the response is not linear. Consider the size of your Variable Resistor, too. at 1K and 5V you'd have this sucker shut off. Learn to pulse modulate. At the low voltage and low current your Arduino pins run, you're using a cannon to remove a mosquito from your forehead. A Variable Resistor is too crude and overpowering of an instrument to be used in that application. Learn to pulse modulate.

Voltage is irrelevant with LEDs, limit your current and the voltage will automatically be in range. LEDs are Current Driven devices. Ohm's law is not complicated. Use it and your problems will disappear.

I have a few dozen of these, most many years old. No problems. Work great if you know how to use them properly.

Comments about RadioShack 5mm High-Brightness White LED (2-Pack):

I used these LEDs to play with my Arduino. I hooked up my potentiometer to fade it, but it turns out that the LEDs don't fade. They only turn on or off. They don't work if they have less power than a pre-defined threshold.

Comments about RadioShack 5mm High-Brightness White LED (2-Pack):

I'm using a 5 volt dc transformer and a 68 ohms resister. The lights start our almost white then over a few minutes turn blue.

Comments about RadioShack 5mm High-Brightness White LED (2-Pack):

used it in the pair with a 9V battery and resistor in a small project box and on/off switch and discovered it should work for about 36-40 hours straight. longer if only used in emergency. gave it to my kid as a flashlight he can play with for hours

Comments about RadioShack 5mm High-Brightness White LED (2-Pack):

I use these LED's to replace the original light bulbs in my "O" scale locomotives. They stay at a constint brightness at any speed without dimming like regular bulbs. This is a super product.

Comments about RadioShack 5mm High-Brightness White LED (2-Pack):

In response to jim from Cambridge, MA:

LEDs DO NOT have a specific resistance. The resistance of a LED is dependent on the current passing through it at any given moment.