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manual TNC2H, DIN-A-4 Winword. (480kB zip)
manual TNC3S rev. 'K' (Hardware), DIN-A-4 Winword. (850kB zip)
manual TNC31S rev. 'B' (Hardware), DIN-A-4 Winword. (770kB zip)
software-manual TNC3/31 (not up-to-date) (400kB .pdf)
What is KISS and SMACK mode? (Protocol definition TNC <-> PC)
modification instructions for various radios for 9600 Baud use
manual for the TRX4S high speed data transceiver (1.6 MB .pdf)