Thread: Infrared over Headphones
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Copernicus is offline Copernicus
2013-06-06 , 16:23
Posts: 1,986 | Thanked: 7,698 times | Joined on Dec 2010 @ Dayton, Ohio
#11
Originally Posted by pichlo View Post
I wonder what the frequency response of that mic input is. I would not expect it to go far beyond 15kHz, and even that is very optimistic. It is probably limited to something like 4kHz, just enough for speech. The carrier frequency on many remotes go to tens of kHz.
Yeah, the most common carrier frequencies I've seen are around 33 kHz, 38 kHz, and 55 kHz. On the other hand, since we're just receiving IR here, it isn't 100% necessary to be able to recognize the carrier spikes; their only purpose, really, is to help separate the signal from the noise. If we can at least pick out the "on" and "off" periods in the signal, that is sufficient to learn commands, and that generally doesn't require nearly as much accuracy...
 

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