How many volts do I need to power a white 3mm LED that has a 240 ohm 5% resistor attached to it? Answered
I sacrificed a string of battery powered Christmas lights hoping to be able to use the LEDs in other projects. The whole string contains 18 LEDs, every 4th of which blinks and is powered by 4 AA batteries.
The resistors attached to the LEDs are very small and look like they have red, yellow, brown and gold bands, which is how I came up with 240 ohms, but I'm not positive I'm seeing the colors correctly. The yellow may be white. Is there such a thing as a 290 ohm resistor?
I'm determined not to let good LEDs go to waste, but I don't want to just try random batteries and hope for the best. I want to use the right combination to get the most life out of both the LEDs and the batteries. Thanks in advance for your help.