110 Baud modem

[dwight]

Rtty was fsk. You needed a scope or a needle to

indicate when the BFO was centered.

That would be tuning.

I think the Wiky was talking about the 101 standard, not

the hardware.

One wonders what all the terminal strips were for.

Maybe more phone line or you could connect to more

TTYs

Dwight


________________________________
From: cctalk <cctalk-bounces at classiccmp.org> on behalf of Paul Koning via cctalk <cctalk at classiccmp.org>
Sent: Tuesday, May 9, 2017 7:39:00 AM
To: Pete Lancashire
Cc: General Discussion: On-Topic and Off-Topic Posts
Subject: Re: 110 Baud modem

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
>
>
>
>