9 May
2017
9 May
'17
9:16 a.m.
The relays are for controlling the modes function/mode. For example if the
unit is put in local mode, or when an incoming call is "Answered" the motor
will start running.
On Tue, May 9, 2017 at 8:22 AM, Anders Nelson via cctalk <
cctalk at classiccmp.org> wrote:
Good lord, is that a pile of relays to click out bits
rotary-style?
=o
--
Anders Nelson
+1 (517) 775-6129
www.erogear.com
On Tue, May 9, 2017 at 7:39 AM, Paul Koning via cctalk <
cctalk at classiccmp.org> 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
wonder
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 what those rows of large relays are for.
paul