Packet radio uses a protocol called AX.25, a derivative of X.25, which was one of the first computer networking protocols. The innovation of packet-switching lies in its ability to divide data into small "packets," transmit them individually, and reassemble them at the receiving end. This method allows for efficient error correction and retransmission, which was groundbreaking in the days before widespread internet connectivity.

Key Components:

• Radio Transceiver: Most commonly operates on VHF (2 meters) or UHF (70 centimeters) frequencies.

• Terminal Node Controller (TNC): The original hardware device used to encode digital data into modulated audio signals for transmission and decode received signals back into digital data. Modern setups often use software-based TNCs.

• Computer or Raspberry Pi: Runs packet communication software to manage data transfer, messages, and network connections. Or if your using a physical TNC, usually just a way to connect to the TNC to access it's console. You could use programs such as Putty