[andrzejpw]

I was looking into getting a blue LED for my meta42.

http://www.mouser.com/index.cfm?hand...oductid=530835

According to my calculations, I will equal 3.7 mA with an 18V psu and a 4.7K uF resistor + 200.

Is this enough for a blue LED? How much power do they need? I've never worked with them before.

 

[andrzejpw]

anyone? I'm sure you guys do this stuff in your sleep!

 

[Megadeus]

Try this page. Using LED voltage of 3.8, current rating of 20mA, supply voltage of 18V, that calc'd out to a 710 ohm resistor for max brightness.

Not really sure if you can increase the resistor value a lot to reduce the current draw. I think the blues (and whites) require more current to operate correctly.

 

[tangent]

I think you should experiment with this -- who knows what N lumens really looks like until you see it?

Since the quality of the LED resistor doesn't matter, you can just get a random assortment of carbon resistors and try them. $8 will get you 500 assorted carbon resistors at Radio Shack. This is perfect for experimenting with things like this.