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LED project Answered

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Here is what I got going;
I want to use a 9v battery to power a led for a project on one of my guitars. I'm not sure what kind of resistor I would need. On hand I have a 33ohm and 1m resistors. The led is a 5mm cylinder with an inward cone on top. The led ranges from red, blue, yellow, and green in different patterns. It came from a light up snow flake and the original power source are 3 LR44 button batteries. I'm not sure what rating the led is, since I didn't see anything on the packaging. The schematic is just the same as the original setup minus the 9v(LR44s) and the switch(little slider).

Thanks in advance for the help!

2 Replies

The Guitar (author)2009-11-16

did some searching and i couldn't find an exact match for a 5mm rgb column led, but the other 5mm columns had 20mA and a drop that ranged from 3-3.6v and then 5v
3-3.5v = 300ohm
3.6= 270ohm

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NachoMahma (author)2009-11-14
.  It's going to take somewhere in the neighborhood of 300 ohms, but it depends on how much current the LED is rated for. Try searching for
LED +resistor
here on Ibles or on Google.

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