[aprssig] FW: reading aprs path question

[Curt, WE7U]

On Mon, 5 Feb 2007, Robert Bruninga wrote:

> > What is the alphanumeric code that appears
> > in the beginning of many APRS packets/paths?
> >                   vvvvvv
> > Raw packet: K6JLW>APT310,WIDE2-2,qAR,K6TZ...
>
> That is the APRS version field.  All APRS packets are sent to an
> APxxxx address.

Well _most_ anyway!  There are always exceptions to any rule, and in
this case Mic-E format packets are that exception.

Mic-E packets commandeered that field for part of the positioning
info.  They stuff a compressed version of the latitude there and the
100's indicator of the longitude in order to save bytes.  Makes for
some weird-looking packets if you're watching the raw packet data as
someone drives around.

--
Curt, WE7U.   APRS Client Comparisons: http://www.eskimo.com/~archer
"Lotto:    A tax on people who are bad at math." -- unknown
"Windows:  Microsoft's tax on computer illiterates." -- WE7U
"The world DOES revolve around me:  I picked the coordinate system!"