> Pressure at any altitude is:
> 
> P(z) = P(0)*(1- 0.02255z)^5.256
>      where P(z) = pressure (mb) at z km above sea level
>                P(0) = pressure (mb) at sea level

Exactly what I was wondering about...
 
> Oh, and you will need a really good filter between the
> sensor and the ADC, as well as some digital filtering as well.
> Make sure that you verify that the granularity of the adc and
> your op-amp circuit so you get the required resoution.

I not too long ago did a project watching fairly rapid changes in
pressure on a transducer.  It amazed me how much a little
filtering and REALLY good bypassing on the power did for the
signal integrity, or rather, how crappy the signal was before I
"massaged" it some.
 
> I can't tell you too much more than that until after Dec 3rd. (I'm
> working on a contest entry!)

Oh dear!  I hope it's not for CC's PSoC contest...that's what I had
in mind for this!  I hope your project idea isn't too close to mine.
Of course, if you're actually *working* on it, you're steps ahead of
me.  I'm notorious for what I don't get around to...

Thanks so much!

Mike H.

> ken
> klumia@adelphia.net
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