so ive been trying to get my APRS setup working for about two weeks now and im starting to wonder if im just doing something fundamentally dumb. running a Mobilinkd TNC3 into my FT-65 on 144.390 and i can hear packets coming through fine on the radio, SDR shows traffic on the freq, but nothing i send ever shows up on aprs.fi. i've got the path set to WIDE1-1,WIDE2-1 which should be fine for my area right? there's a digipeater maybe 8 miles out that i can see on the map picking up other stations.

the TNC is synced and i can see it transmitting, the PTT fires, the radio keys up. i even checked the audio levels and they look reasonable in the Mobilinkd app. the only thing i havent ruled out is the deviation being off — maybe the signal is too narrow and the digi just isnt decoding it? or maybe my callsign isnt set right in the config. honestly at this point ive gone through the settings so many times they've all blurred together.

anyone dealt with this before? im in a semi-rural area if that matters, Kansas, not super dense digipeater coverage but there should be enough to hit something.

deviation is almost always the culprit when the radio keys up fine but nothing decodes on the other end. the FT-65 especially can be finicky with external TNCs because the audio level into the mic input varies a lot depending on how you're wired up. if you're using the speaker/mic jack combo on that radio you might be feeding too hot or too cold into the TNC. what does the Mobilinkd app show for the TX audio level? there should be a way to monitor it. you want the deviation around 3-3.5 kHz for APRS, too much and it splashes everywhere and nobody decodes it, too little and it just doesnt punch through.

also double check that your SSID is actually set to something — i've seen people leave it blank and some igates/digis get weird about that. and make sure you're not sending from inside a building with the HT right next to a computer or anything generating noise, sometimes that causes weird packet corruption before it even gets transmitted. 8 miles to a digi on an HT in Kansas should be totally workable on flat terrain though so it's gotta be something in the signal chain.

yeah check the deviation first like the other guy said but also — have you tried running direwolf on a PC with a cheap SDR and just monitoring your own packets locally? like set up a receive-only direwolf instance and see if it can even decode what you're putting out. if direwolf cant hear you then nothing else will either. that diagnostic step saved me like a week of confusion when i was first setting up my station.