Originally Posted by theothertim
does anybody know how to make an LED light setup? I know that resistors are involved because too high wattage will cause problems in the LEDs. the question I have is whether or not several leds need several resistors, or if one resistor will work for say 20 LEDs. I have an idea for making a bicycle light that will be csomething close to infinately variable using a switch that will allow you to turn on one more led at a time. Whether or not it will work is another thing thing entirely.
Headlight or tail light?
In any case, yes, you can use one resistor for a few LEDs. It depends on the voltage. For 12V systems, you can use five LEDs and one resistor.