That's cool!
I'm thinking I might be able to do something like that.  The project is
similair where someone breathes through the cannula, and I need to tell
when they inhale so this would probably work well.  I was thinking of a
rubber membrane that would have a wire or piece of metal attached and
when you breathe in it moves and close a switch.  But I was thinking
there may not be enough movement.  However using capacitance I probably
wouldn't need to move very far to see a big change in freq.  Any
thoughts on this anyone?  Whould a switch or capacitance work better?

Thanks Brian even if this doesn't work it was cool to learn about,
Aaron

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