110 Baud modem

Pete Lancashire pete at petelancashire.com
Tue May 9 09:57:13 CDT 2017


Wikipedia is wrong a lot of times. Usually in the details.

Modem or MOdulator DEModulator had to come about when one could finally put
a modulator (voltage or current loop) in and get a modulated signal out,
and the reverse, and thirdly all the control circuitry to automate things.

Long before that, each function was separate.

I can find 1958 and SAGE but non have any proof, and many references are
circular.

On Tue, May 9, 2017 at 7:39 AM, Paul Koning <paulkoning at comcast.net> wrote:

> 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 <pete at petelancashire.com>
> 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 <paulkoning at comcast.net>
> wrote:
> >
> > > On May 8, 2017, at 10:27 PM, Pete Lancashire via cctalk <
> cctalk at classiccmp.org> 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
> >
> >
> >
> >
>
>
>


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