[aprssig] The best resolution of position from APRS

J. Lance Cotton joe at lightningflash.net
Thu Jan 5 12:34:02 EST 2006

Curt, WE7U wrote:
> Imagine using the !DAO! thing, sending out a higher resolution
> object from SAR base.  Imagine that the objects is placed on one
> side of a raging whitewater creek or river, impassable.
> A D700A user sees the object on the LCD or on his attached GPS,
> figures out a route to it on his detailed map, and drives to the
> wrong side of the river due to the D700A not understanding the !DAO!
> extension.  He's only got about 60' resolution with MIC-E or
> standard APRS packets.  This could be life-threatening due to the
> delays it could cause!

Well, the idea of using a special delimiter in the free-form text field, 
like !DAO! is so that the extra information is still human readable.

So the D700 user would have to ensure that he/she checks out the full raw 
packet for the object and decode the characters into the appropriate numbers 
and add them either mentally or on a paper map plot and THEN they would have 
a full understanding of the object's location.

Though, for your particular case, I might just put the text "East of Big 
River" in the freeform text field. ;-)

J. Lance Cotton, KJ5O
joe at lightningflash.net
Three Step Plan: 1. Take over the world. 2. Get a lot of cookies. 3. Eat the 

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