This is the "Reply-Ack" feature.
It's not part of the 1.0 APRS spec, it's in one of Bob Bruninga's "addenda" http://www.aprs.org/aprs11/replyacks.txt The short story is that it improves messaging, because the reply to a message contains an "ack" of that message. This is just in case the real "ack" got lost. On Tue, Oct 26, 2021 at 11:56:22PM +0200, we recorded a bogon-computron collision of the <krist...@skypro.be> flavor, containing: > Hi all, > > > I am working on a project to extend the firmware of the TTGO > (aprs-over-LoRa) iGate software. > https://github.com/on1arf/LoRa_APRS_iGate > > > I am currently doing some additional work on the APRS-IS to RF gateway, > specially for APRS "Message" packets. > > > I am using xastir on my linux laptop to test out my code. > (my igate has ON1ARF-12, my linux laptop/xastir has ON1ARF-14) > > > A test message I received is this: > > ON1ARF-14>APX215,TCPIP*,qAC,NINTH::ON1ARF-12:test 1.2.3.{3y}12 > > > Can somebody help interpret this message? > > Looking at the "APRS 101" document (which I guess can be considered to be > the more-or-less official specification for APRS), this seems to be a normal > "Message" APRS-message, with message identifier (which should be > acknowledged by a reverse "ack" message). > > But as I had just previously received a "ack12" in a previous message from > the xastir station, it looks like that the "{12" is in fact a repetition of > that. > > > So, can I interpret this message as a combination of two messages: "test > 1.2.3.{3y" and "ack12" > > I do not find anything in the "APRS101" document (version 1.0.1 d.d. 29 Aug > 2000) that describes this kind of "two-in-one" messages. > > So, I am a bit confused why xastir sends this kind of messages packets. > > > > Can somebody shed some light on this? > > > 73 > kristoff - ON1ARF > > _______________________________________________ > Xastir-dev mailing list > Xastir-dev@lists.xastir.org > http://xastir.org/mailman/listinfo/xastir-dev -- Tom Russo KM5VY Tijeras, NM echo "prpv_a'rfg_cnf_har_cvcr" | sed -e 's/_/ /g' | tr [a-m][n-z] [n-z][a-m] _______________________________________________ Xastir-dev mailing list Xastir-dev@lists.xastir.org http://xastir.org/mailman/listinfo/xastir-dev
