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Unread 28-02-2008, 15:30
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Kevin Watson Kevin Watson is offline
La Caņada High School
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Re: IR LED wavelength requirement

Quote:
Originally Posted by Joohoo View Post
howdy everyone, I have been thinking about all the talk about people hacking apart remotes, putting infrared LEDs in series and the like. Our team has a simple remote control for our transmitter and is using the FIRST supplied ir receiver. I was wondering that if I were to hack a few more infrared LEDs into the remote, what wavelength LED would I need to use?
I know it would have to be considered infrared but within, but does the ir receiver only recognize certain wavelengths of infrared emission? Does it really matter? Ive been looking at a bunch of LEDs with 940nm and some with 850nm wave lengths. Any help would be greatly appreciated.
I suspect more can be gained by moving the carrier frequency away from the usual 38KHz to 56KHz. This would, of course, mean that you'd have to find a remote that used a 56KHz carrier, or invent your own. If you're really hard-core, you'd invent your own data protocol with a error detection (and possibly error correcting) wrapper to ensure you're getting good data. You might get some ideas by studying my 2004 beacon code and transmitter circuit. A perfect transmitter waveform generator would be a EDU or Vex robot controller. Of course, if enough folks are interested, I'd be willing to help out.

-Kevin
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Kevin Watson
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