110 Baud modem
Paul Koning
paulkoning at comcast.net
Tue May 9 09:39:00 CDT 2017
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
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> On Tue, May 9, 2017 at 6:47 AM, Paul Koning <paulkoning at comcast.net> wrote:
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> > 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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