I've been looking around for a sensor that is capable of detecting the presence of a person's breath. It needs to fit inside a tube that a person will blow on. Detecting the force of the person's breath is not important at all, I just want to detect movement of air caused by someone blowing on the tube.
Is there a sensor that can help with this that will run on a 3.3V circuit? I can't seem to find something online, that's small enough to fit inside a tube around just below 1" in diameter.
Any recommendations. I've been searching catalogs for our local vendors till I'm blue in the face, but just can't seem to find something suitable.