hey all,
i feel stupid asking so many LED questions, i really don't know much about them though. i guess my question stems with the question of whether resistors limit current or voltage. I thought current but the guy at radio shack said voltage. so which is it. then secondly, i measured the voltage going to my keyboards LED and measured 2volts so if i want to replace them i buy LED's rated at 2 volts right? third, are there any stores (online or otherwise) that have pretty much every kind of LED out there. cuz i can't find any blue 3mm 2 volt LED's at any of the stores i know of.
sweet
thanks,
- legit

Not sure about the resistor question, I have wondered that and how they would work myself too. But I do know that you will more than likely have to go with 3.3 volt LED's, don't think they make 2v, but a 3.3v should work fine, but just wouldn't be as bright as it could be.

V=IR, so if you keep the voltage the same and increase the resistance, you lower the current.

there isn't really such thing as a 2V led... measure the current through the led pins as that's more important... the 2V is the "voltage drop" across the led... it's not the voltage supplied to the led...

(Vs - Vf) = IR

Vs: supply voltage
Vf: forward voltage drop of LED
I: current through LED
R: value of led series resistor...

but... basically just get any blue led if you're doing a straight swap...