There’s an IP based version of ACARS and other technologies I’m not familiar with.Is the replacement ACARS a digital mode, what's the difference between them?
If you’re on a major flight path you should get data fairly often. Put the ACARS frequencies in a bank, set mode to DATA and scan just those for a hour or so. You’ll hear the buzz and the message, if decoded, will be listed in the Message Log. It saves up to 10 messages. I turn on my GPS, but I’m not sure it’s required to RX.