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  • How to Install Load Resistors for LED Turn Signal Lights

    Usage of the term "load resistor" in this context made me cringe. A load resistor is something you might use when testing a power supply to simulate a load, or on an audio amplifier you just repaired and you want to do a "burn in" test by cranking it at full volume overnight into a dummy load without making any noise to test it.This is a current limiting resistor https://en.wikipedia.org/wiki/Current_limiting and you use Ohm's law or an online calculator to figure the value. There are a slew of them, look at https://duckduckgo.com/?q=%22current+limiting%22+r...If you want to run a single cheapo LED from 12 volts you probably want a maximum current of 20 mA or 0.02 amps. This calculator http://ledcalc.com/ says you want a 470 ohm resistor and it needs to be at l...

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    Usage of the term "load resistor" in this context made me cringe. A load resistor is something you might use when testing a power supply to simulate a load, or on an audio amplifier you just repaired and you want to do a "burn in" test by cranking it at full volume overnight into a dummy load without making any noise to test it.This is a current limiting resistor https://en.wikipedia.org/wiki/Current_limiting and you use Ohm's law or an online calculator to figure the value. There are a slew of them, look at https://duckduckgo.com/?q=%22current+limiting%22+r...If you want to run a single cheapo LED from 12 volts you probably want a maximum current of 20 mA or 0.02 amps. This calculator http://ledcalc.com/ says you want a 470 ohm resistor and it needs to be at least a 1/4 watt resistor.

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  • ab1jx commented on Dipankar's instructable LED CHANDELIER10 months ago
    LED CHANDELIER

    I was wondering when I saw the cube if you had angled the individual LEDs to try to give continuous coverage. Most LEDs I've seen only spread light over a 15 - 30 degree angle. I'm still trying to figure out the best way to do that in 2 dimensions. These spread light over 180 degrees but it's a band about 15 degrees high. I worked out the angles carefully and set them into some PVC pipes. All the LEDs are on, you only see light from a few at the right proper angles.

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