>> How are you going to account for barometric pressure differences: the
>> ~ in your 10^-4 constant?

> I have a plan.  My NDA prevents saying how.  My plan might even work !
> Gus

Maybe pass the same signal thru the same air at a built-in target at known 
distance within the housing of the unit to back out the ~.

-Chris

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| Christopher Cole, Cole Design and Development, LLC          cole@coledd.com |
| Embedded Software Development and Electronic Design       http://coledd.com |
| Stow, Ohio, USA                                                800-518-2154 |
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