[aprssig] Position Ambituity in APRS!

Robert Bruninga bruninga at usna.edu
Tue Jan 8 13:19:24 EST 2008

> The APRS spec is of course the overriding 
> authority here.  It specifies truncation 
> of lat/long least significant digits as the
> means of conveying ambiguity. 

Unfortunately, This is the incorrect interpretation that
continues to propogate.  But it is simply wrong.

The spec does not say anything about truncation.  It says that
if less than the full DEG, MIN and decimal hundredths of minutes
of precision are available, then those unavailable digits are
transmitted as SPACES.

This is not truncation.  It is transmitting to the receiver only
the information available to the sender.  I felt very strongly
about this, so that people would not insert zeros as fillers.
Yet, unfortunately, that is exactly what happens in many

Bob, WB4aPR

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