[aprssig] Standardized format of WX data in APRS?

Robert Bruninga bruninga at usna.edu
Mon Feb 13 10:54:39 EST 2017

Since PeteBros changed their Utilimiters to output directly into the APRS
format more than a decade ago, I wonder if there are any of the original
such raw packets on the air.   If not, I would propose deprecating those
from the standard?

And Yes, the argument remains.  When I am mobile and get a WX report that
contains no position info (that is only transmitted once every 30 minutes)
the WX report on the front panel of my radio is completely useless.  It
could be from 3 counties away.  And may remain so for an hour or more if
that one position packet is missed.  AND by that time I am out of area and
APRS failed me.  It failed to give me relevant info even thought it was
transmitted and took up air time.

APRS was always intended to serve the mobile operator (not the shack-potato
sitting in his shack with full internet access to all possible weather
services instantly)... hence the argument remains for me.  The incomplete WX
format is an anathema to me <wink>  ;-)  Bob

-----Original Message-----
From: aprssig [mailto:aprssig-bounces at tapr.org] On Behalf Of Steve Dimse
Sent: Monday, February 13, 2017 9:48 AM
To: TAPR APRS Mailing List
Subject: Re: [aprssig] Standardized format of WX data in APRS?

> On Feb 13, 2017, at 9:27 AM, Robert Bruninga <bruninga at usna.edu> wrote:
> The other format I never liked uses two separate packets.  I call them
> the "positionless weather" packet and the "weatherless-position" packet.

There is nothing like a twenty year old argument that just won't die. The
reason in favor of separating the two is weather station positions don't
change, so sending many needless positions wastes bandwidth.

But this guy's question doesn't require restatement of the argument. The
answer is the protocol for APRS is very complex. You can download it here:


There is a lot in there besides weather, so don't get too discouraged by its

There are more than the two weather formats Bob mentioned. There are also
two Peet formats, the compressed position format, and perhaps more that
escape my memory now.

This spec addresses the data formats. What is displayed on screen for a
weather station is up to the author of the client software, there are dozens
of different ones to choose from.

Steve K4HG

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