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Information: In 1969, the Meteorological Branch,
Department of Transport inaugurated its new national teletype system.
In contrast to the previous teletype network, which had been based on
manual, torn-tape switching and distribution of message traffic, the
new system, operated on behalf of the Meteorological Branch by CNCP
Telecommunications, was completely computerized, using CNCP's dedicated
Collins C8500 message switch located at 151 Front Street West in
Toronto. The Met Branch was a very early adopter of the new computer
switching technology, being only the second corporate customer of
CNCP's automated offering. The change to the new network was also
marked by the transition from the 5-level Baudot character code to the
then relatively-new 8-level ASCII code (the American Standard
Code for Information Interchange), with
most collection and distribution circuits operating at 110 bits per
second ("110 baud" -- 10 characters/second, 100 words per minute).
The machine shown was typical of the new terminal equipment
installed at Met Branch sites across the country. This was the Teletype
Model 35 ASR (typically referred to as an "ASR-35"), with "ASR"
identifying it as being capable of "Automatic Send and Receive".
The ASR-35 included a keyboard, a printer, a paper-tape punch
('perforator"), and a paper-tape reader ("transmitter/distributor").
Messages were prepared for transmission by being punched onto paper
tape from the keyboard. The tape was then set in the reader and was
read in for distribution by the computer message switch when the
appropriate "poll" character sequence was received and identified by an
additional piece of equipment known as the "selector", which
automatically started the reader.
The ASR-35 was a completely electromechanical device -- no
electronic components were employed, just an extremely complex system
of motor-driven gears, shafts, cams, and levers. A lighter-duty (and
less-expensive) version, the ASR-33, became well-known as the standard
console for small computer systems throughout most of the 1970s..
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