So Wikipedia is wrong, since it claims that it was introduced in 1958 for ASCII
and 110 Baud.
Then again, 101/103 modem modulation doesn't care about speed (it isn't
clocked) up to a limit of 300 baud or so.
I wonder if there is also terminology here: what we now call a "modem" was
earlier called a "tuning unit" and that term goes back to 5 bit machines and
the 1950s. It may be more a radio TTY term than a landline term, but the
concept is identical. I remember QST articles around 1958 or so about RTTY
tuning units, built out of tubes with a relay (differential relay?) thrown in
for good measure.
paul
> On May 9, 2017, at 10:32 AM, Pete Lancashire <[email protected]> wrote:
>
> The C version came later with the introduction of ASCII ( 5 to 8 bits ) and
> 110 baud. So it does not go back to the 50's.
>
> I do not know when the C version was released. The ASCII Teletype Model 35
> was introduced in 1961.
>
> -pete
>
>
>
>
> On Tue, May 9, 2017 at 6:47 AM, Paul Koning <[email protected]> wrote:
>
> > On May 8, 2017, at 10:27 PM, Pete Lancashire via cctalk
> > <[email protected]> wrote:
> >
> > Bell 101C
> >
> > https://goo.gl/photos/hrhAwvzMBLWWteXu6
> >
> > https://en.wikipedia.org/wiki/Bell_101
>
> Interesting. Released in 1958 but that unit is stamped 10 years later.
>
> It would be nice to see photos of the circuit boards. And I sure wonder what
> those rows of large relays are for.
>
> paul
>
>
>
>
