[ale] WAY [OT] but geeky - how do I calibrate GPS barometric altimeter

[warlord at MIT.EDU (Derek Atkins)]

Scott Plante <splante at insightsys.com> writes:

> Derek,
>   I'm pretty sure Ron realized that--that's why he mentioned getting it from
> online sources for his locality. The problem was they all reported different
> values.

Sure, because the pressure varies by time and location.  If you have
weather stations miles apart and taking readings (or reporting readings)
at different times, you will get different numbers.  So I would expect
to see slightly different numbers from surrounding readings.  Within a
25 mile radius I'd expect no more thant +/- .02, but that's still about
+/- 50'.

-derek

-- 
       Derek Atkins, SB '93 MIT EE, SM '95 MIT Media Laboratory
       Member, MIT Student Information Processing Board  (SIPB)
       URL: http://web.mit.edu/warlord/    PP-ASEL-IA     N1NWH
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