I've been wrestling with my Mobilinkd TNC3 connected to a Yaesu FT-60R for the past week and can't get the audio levels right. I start with TX AUDIO at minimum, slowly increase while monitoring signal strength until it stops increasing, then back off slightly, but I'm still getting decode errors on the other end. My beacons show up on APRS-IS intermittently, suggesting the audio chain isn't optimized. Anyone have experience with this specific radio/TNC combination? Should I be using the mic jack or the dedicated TNC port?

Had similar issues with my FT-60R setup. Set RX AUDIO to maximum on the TNC, then adjust volume on the radio itself rather than the TNC potentiometer. Also make sure you're monitoring local APRS traffic for proper calibration - can't set levels without actual packets to decode.

Check your deviation first! Most TNCs overdrive the Yaesu radios. Use the calibration mode, adjust TX audio until signal stops increasing, then back off a fraction of a turn. I bet you're overdeviating and causing distortion downstream.

Are you using the right cable? The FT-60R needs a specific pinout for packet operation. Connect TNC to radio, pair with smartphone, configure software - should be sending packets within minutes if everything's wired correctly. Double-check your wiring diagram.