How to get the best range out of an IR LED? Answered
Hello, I'm using my Arduino as a universal remote and I've got everything working, but my IR LED isn't really strong. I've read around the internet and all I've found are people using an IR LED with either a 33 Ohm or 100 Ohm resistor in front of it.
Currently I'm using this RadioShack High-Output Infrared LED
[Radiant Power Output = 16mW min
Forward Voltage = 1.2V
Forward Current = 100mA
Wavelength = 940nm]
with a 100 Ohm resistor in front of it and only get a foot or two of range. I'd really like to get out to about 20 feet but I could make due at 15/16 feet. So I got nose-y and opened up my TV remote... it's all surface mount, but as best I can figure it the signal leaves an IC, goes through a 100 Ohm resistor and then goes into a transistor (labeled 2T) before heading out to the IR LED. The third pin from the transistor snakes around to a bunch of other parts and I lost. So I was wondering what to do to increase the range of my IR LED... change the resistor? Power it via a transistor? If I can use a transistor does anybody know how to wire it up?
Any help is much appreciated.