110 Baud modem

[Pete Lancashire]

It would depend on what you wanted to emulate. The 'logic' you see in the
relays and here

https://goo.gl/photos/4sDv7MGRvknugiAGA

Would be very easy.

The logic is to handle auto answer, carrier detect, motor control, local vs
remote loop etc. All the things
that were miniaturized by Penrill and later Hays.

The rest is pretty much analog design. One could fully emulate the circuit
in Spice but that would not give one real time (be fun to see how fast one
could).

-pete





On Tue, May 9, 2017 at 7:29 AM, SPC via cctalk <cctalk at classiccmp.org>
wrote:

> 2017-05-09 15:47 GMT+02:00 Paul Koning via cctalk <cctalk at classiccmp.org>:
>
> >
> > > 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
> >
>
> ​Of course. But I ever guess about the 101 and other early modems... Would
> be possible to emulate them in some way, or their assembly and logic
> wouldn't allow it?
>
> Regards
> Sergio
>
>