Dr Keith Wansbrough (an Auckland University Computer Science and Mathematics graduate, witha PhD from Cambridge, who now works in the IT industry in Scotland) looked at my earlier report(https://vixra.org/abs/2201.0097) and concluded that:a) The DTMF approach would be "fun", but not necessary. Using the serial port of the oldcomputer to extract the data would be much easier than sending DTMF tones through the soundcard and capturing and then decoding them.b) Using a normal (modern, reliable) computer with a serial port (not common nowadays, it seems,unfortunately) to receive the data from the old computer would be easier than using a data logger.However, flow control will be necessary, so a null modem cable with the flow control wires presentand connected correctly will be necessary.I bought a null modem cable from Jaycar, but unfortunately Jaycar do not claim to know the exact wiring of the cable. Given the possible historical value of the data on the old computer, I felt that it would be important for me (or someone else) to carefully check the wiring of the null modem cable (to check that it is correct for this application, and in particular that it has the required flow control wires) before attempting to use it with the old computer in question. I have nearly completed building a reasonably simple apparatus for checking the wiring of the null modem cable, from cheap, readily-available parts. I describe this apparatus here.