As to other comments in this thread:
> 1) Dial up modems were available well before 1973, at least as earlier
> as 1968 as part of Teletype time sharing terminals. These were
> automatic in the sense they would answer a ringing phone line and
> connect up and disconnect and power down upon completition. They
> could remotely start/stop different tasks, like the paper tape punch > and reader.
Paper-tape reader and punch control was an option of the Teletype, not the modem. It could be used even on direct connections.
- David.Thompson1 at worldnet.att.net