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The First TTS on a Linotype

Started by Mechanic, January 27, 2018, 12:53:15 AM

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Mechanic

The Gannett Morely teletypesetter system demonstrated in 1928

These photos are from Harvard Square Library. One shows Frank Gannett holding the tape used in the first demonstration of a teletype machine operating a Linotype. Exactly how this machine worked I have no idea. It is certainly nothing like the Teletypesetters that were around in the 1950's.






George Finn (Mechanic)
Gold Coast
Queensland
AUSTRALIA


John Cornelisse

The code in use was the same as on the Teletypemachines, why change when something has proven itself for decades ?

The ASCII-code later used in computers stems from it.


Mechanic

One of the earliest teletypewriters was invented during the late 1890s by Donald Murray, a New Zealander. Murray was working at The Sydney Morning Herald, in Sydney, Australia, at the time, and he originally intended his machine as an automatic typesetter. Murray's teletypewriter had a rotating drum. When the operator pressed a key, the drum operated a sophisticated electromechanical process that resulted in a unique code for that character being transmitted over telegraph lines. Not getting much support for his prototype in Australia he took it to the United States

https://www.cs.auckland.ac.nz/historydisplays/FifthFloor/Murray/MurrayMain.php


George Finn (Mechanic)
Gold Coast
Queensland
AUSTRALIA


R Kenworthy

This string raises all sorts of issues with the English alphabet and electro mechanical transmission of words for their ultimate conversion to ink on paper.  Way back in 1954/5 I was with the RAF in Changi Singapore providing communications for the RAF using teleprinters, met forecasts and air movements. On return to UK I nearly applied for a job with Linotype, but stayed with GPO (BT today)  the story starts half a century and more before that. I do not claim to know it all and to set it all down would be a 1,000 page book and more. So I am going to give some pointers for those so moved to Google.

Morse code was the standard first adopted for transmission of messages electronically it used long and short intervals of tone or current flow represented as " . " (dot) and  " – " (dash) combinations representing each letter (See Morse Code) these could only easily convert to a single mechanical movement of moving a pen to or from a moving paper tape. Each group of dots and dashes having to be read and mentally converted to letters that were then typed.

See Baudot and CCITT codes - RabbitThe Baudot code, invented in 1870 and patented in 1874 by J. Baudot is a five-bit binary code. Originally used in wireless telegraphy as a replacement for Morse Code. It was adopted as an official international code by the CCITT (Comité Consultatif International Téléphonique et Télégraphique: International Consultative ...

Key strokes are converted to electrical impulses, putting it simply for transmission over wire or radio as "high" and "low" tones at intervals corresponding to the combinations of the five holes arranged vertically in a punched tape.

The tape has an offset sprocket drive dividing two holes and three holes so that it can only be fed in the correct position and travels at a constant speed. Combinations give the 26 letters of the alphabet and mechanical instructions such as space, line feed, return, & and shift. The latter facilitates the ten numbers 1-0 and punctuation see  An introduction to teleprinters and punched tape ... - Sam Hallas   and later  Teletype Model 33 - Wikipedia

Just as an e-mail begins with the recipients and senders addresses a single key stroke gave "HERE IS....."  and "WHO ARE YOU"  produced an "ANSWER BACK" confirming receipt by the right recipient while shift J (key tab " J  BELL")  rang a bell  on the receiving machine. (the PC notifier?)

It should also be born in mind the some pacific alphabets have fewer letters while Iceland and some other EC countries have more, there was also eighteenth century research to add two new characters to the English alphabet "th" and "ng" being the most used combination, as a single character like "&" just think how many key strokes that would save!

Returning to the original string the "high tone"  and "low tone" could easily be converted to electrical impulse and in turn operating a 299AN relay holes below the sprocket causing a DC current to flow + to – while those above caused it to flow in the reverse direction – to + so you had 80 volts + and 80 volts – which in turn operated the punched tape machine punches or in our case the corresponding escapement on the key board (putting it simply)

Turning to transmission speeds Morse was dependant on the skill of the sender to read copy and tap the key. My father was a skilled Post Office Telegraphist and Radio Ham Amateur radio - Wikipedia One of my earliest memories as a child was the description of the battle of the River Plate in 1939 see Battle of the River Plate - Wikipedia live commentary was transmitted from the quayside as well as the other news services it was not released on the BBC immediately. He used to tell me he learned to read the bookmakers "Tic Tac" so earned extra by going to the races and setting up a Morse connection to transmit the odds and results to the Tote. See Tic-tac - Wikipedia

  On the other hand teleprinter speeds are limited by mechanical/electro conversion speeds see Teleprinter - Wikipedia  For example, a "60 speed" machine is geared at 45.5 baud (22.0 ms per bit), a "66 speed" machine is geared at 50.0 baud (20.0 ms per bit), a "75 speed" machine is geared at 56.9 baud (17.5 ms per bit), a "100 speed" machine is geared at 74.2 baud (13.5 ms per bit), and a "133 speed" machine is geared at 100.0 baud ...   History • ‎Ways in which teleprinters ... • ‎Teleprinter operation Manufacturers  see also  Telex - Wikipedia  you will appreciate from the above that speeds increased over the years but 50 years ago they were running at about the same speed as a Linotype could set a column width.

See Pangrams > Example pangrams - Fun With Words these are sentences using the maximum number of punch variations and thus relay changes at typing speed used along with RYR and SNIE  sent continuously to check equipment performance many codd messages were transmitted in five figure groups
It was anticipated  that after the Normandy landings the advance would be dependent on a secret communications system, the civilian network would probably have been destroyed. The answer was the "10 Set" these were trucks with two UHF dish aerials on top their own on board generators and equipment that permitted ten telephone or ten multi channel teleprinter signals to be sent. They were tuned using an oscilloscope and adjusting a magnetron beam.  They only worked "line of sight" so could not be intercepted coupled to them was the VF equipment (Same as I worked on in 1954) and the Defence Teleprinter Network (DTN) table  The ERA 1 Speech and Telegraph Networks - Ringbell this was  a steel table with a teleprinter punch tape machine if required, telephone and 80+x 80- power supplies. We set two up from Chester to North Wales as a training exercise.

The trade magazine Printers Sales and Wants, Benn Bros, Tonbridge Kent had an article in the 1970's? (no longer published) about the setting of New York papers simultaneously in Paris and London on these machines. Can't find it on line sorry.

That's enough don't just look at the links above scan the whole Google page there is masses of material out there

Keri Szafir

An interesting, even if chaotic, read on early telecommunications. Back before we had the ISO/OSI model, IP protocol, Ethernet - hell, even electronics ran on vacuum tubes.

I wonder if the transmission of these 7 bits was parallel, or serial. Parallel would need at least 8 wires (7 for data and one for ground). Serial (used everywhere nowadays - I2C, SPI, UART/RS232, USB...) needed a specified packet format - i.e. a preamble, some bits for data, then a termination sequence.  I can't see how it could be practical before we started using microprocessors and software to code and decode these packets.
"Any sufficiently advanced technology is indistinguishable from magic." --Arthur C. Clarke
"A thing of beauty is a joy for ever." --John Keats

https://youtube.com/KeriSzafir
Founder and owner of Keritech Electronics

Mechanic

If you really want know how teletype can send specific characters over a telephone line, you might like to study this document.


http://www.samhallas.co.uk/repository/telegraph/introduction_teleprinters_1958.pdf
George Finn (Mechanic)
Gold Coast
Queensland
AUSTRALIA

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