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[aprssig] Re: PHG and HAAT

Stephen H. Smith wa8lmf2 at aol.com
Fri Oct 14 20:17:31 UTC 2005


n0yxv at gihams.org wrote:
> Ops sorry still can't figure out how you can get a negitive number. According to
> how to figure HAAT in previous posts you couldn't get lower than a zero. Maybe
> figuring HAAT is so simple I'm missing something. 
Simple...  If you happen to have a lower ABSOLUTE altitude than the 
majority of sample points on the radials extended outward from your 
location (using the FCC technique of computing HAAT), you will get a 
negative HAAT.    

In other words, if you are down in a hole with higher terrain all 
around, you have a negative HAAT.  Typical of populated areas on the 
floor between mountain ranges such as Aspen or Vail, CO.   Or in Death 
Valley.    Or in the valley at Yosemite National Park.    Or Rocky Mtn 
National Park (if you are in the center basin, not up on the ridge).   
Or many communities on the flood plain below the bluffs on each side of 
the Mississippi River.   Etc. 




Stephen H. Smith    wa8lmf (at) aol.com
EchoLink Node:      14400    [Think bottom of the 2M band]
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Home Page:          http://wa8lmf.com

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