One thing to bear in mind, if anyone feels like trying out this old stuff, is that modems relied on the latency being absolutely fixed; as was guaranteed in the

One thing to bear in mind, if anyone feels like trying out this old stuff, is that modems relied on the latency being absolutely fixed; as was guaranteed in the POTS network - and of course an analogue connection. Modern VoIP calling does not guarantee this at all, and even if you have a landline it will almost certainly have been converted to run on VoIP by now. There were compatibility fixes (such as V.150.1) but given the limited usage it would not be surprising if they have bitrotted at this point.