[GreenKeys] FAA Teletypewriter Network 1959

[Jim Haynes]

On Sat, 3 Oct 2020, Jim Cooper wrote:

> Some of the R/T worked also as speed changers;
> either from 60wpm to 100wpm (or 67wpm, 50 baud
> for European circuits) ... or in a clever arrangement
> where WorldComm sold "half speed" and "quarter
> speed" overseas circuits.  The XD in the R/T set
> would be 'paced' to send a character at channel
> speed, but only every other character or every
> fourth character.  These channels were then time-
> division multiplexed onto the full-speed undersea
> cable channel.
>
Packet switching as we know it pretty well demands computer technology.
Western Union did something a little bit like you describe which
they called Varioplex.  See Western Union Technical Review.  They
would connect a number of virtual channels to a smaller number of
real channels.  They let each user send a certain number of characters
and then switch to the next user.