Often in packet radio you will see output like this

But what does it all mean?

One OARC member, Perry 2E0ITB, came up with the following succinct explainer:

RR is “Receive Ready”

UA is “Unordered Acknowledge”

I is information frame.

UI is unordered information

the C/R after that is “command” / “response”

P/F is “poll” / “final”

While the C/R and P/F stuff is used in the protocol, in general it's ignorable, just the first bit is the most important.

S# and R# are “sequence #” and “received #” and are used to say what sequence number this packet is, and what sequence has been received.