From: fungus@amongus.com.invalid   
      
   From the «punchity punch punch» department:   
   Title: A Teletype by Any Other Name: The Early E-mail and Wordprocessor   
   Author: Al Williams   
   Date: Wed, 13 Nov 2024 15:00:37 +0000   
   Link: https://hackaday.com/2024/11/13/a-teletype-by-any-other-na   
   e-the-early-e-mail-and-wordprocessor/   
   Podcast Download URL: https://hackaday.com/wp-content/uploads/20   
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   [image 1]   
      
   Some brand names become the de facto name for the generic product. Xerox, for   
   example. Or Velcro[2]. Teletype was a trademark, but it has come to mean just   
   about any teleprinter communicating with another teleprinter or a computer. The   
   actual trademark belonged to The Teletype Corporation, part of Western   
   Electric, which was, of course, part of AT&T. But there were many other   
   companies that made teleprinters, some of which were very influential.   
      
   The teleprinter predates the computer by quite a bit. The original impetus for   
   their development was to reduce the need for skilled telegraph operators. In   
   addition, they found use as crude wordprocessors, although that term wouldn’t   
   be used for quite some time.   
      
   Telegraph   
   [image 4][4]An 1855 keyboard telegraph (public domain).   
      
   Early communication was done by making and breaking a circuit at one station to   
   signal a buzzer or other device at a distant station. Using dots and dashes,   
   you could efficiently send messages, but only if you were proficient at sending   
   and receiving Morse code. Sometimes, instead of a buzzer, the receiving device   
   would make marks on a paper — sort of like a strip recorder.   
      
   In the mid-1800s, several attempts were made to make machines that could print   
   characters remotely. There were various schemes, but the general idea was to   
   move a print head remotely and strike it against carbon paper to leave a letter   
   on a blank page.   
      
   By 1874, the Frenchman Èmile Baudot created a 5-bit code to represent   
   characters over a teleprinter line. Like some earlier systems, the code used   
   two shift characters to select uppercase letters (LTRS) and figures (FIGS).   
   This lets the 32 possible codes represent 26 letters, 10 digits, and a few   
   punctuation marks. However, if the receiver missed a shift character, the   
   message would garble badly. This was especially a problem over radio links.   
      
   Paper Tape   
      
   Donald Murray made a big improvement in 1901. Instead of directly sending   
   characters from a keyboard to the wire, his apparatus let the operator punch a   
   paper tape. Then a machine used the paper tape to send characters to the remote   
   station which would punch an identical tape. That tape could go through another   
   machine to print out the text on it. Murray rearranged the Baudot code   
   slightly, adding things we use today, like the carriage return and the line   
   feed.   
      
   The problem that remained was keeping the two ends of the circuit in sync. An   
   engineer working for the Morton Salt Company solved that problem, which Edward   
   Kleinschmidt independently improved. The basic idea had been around for a while   
   — using a start pulse to kick off each character — but these two patents   
   around   
   1919 made it work.   
      
   Patents   
      
   Instead of fighting a big patent war, the two companies, Morkrum (partly owned   
   by the owner of Morton Salt) and Klienschmitt, merged in 1924 and produced an   
   even better machine. This was the birth of the modern teleprinter. In fact, the   
   company that was formed from this merger would eventually become The Teletype   
   Corporation and was bought by AT&T in 1930 for $30 million in stock.   
      
   Some early teleprinters were page printers that typed on the page like a   
   typewriter. Others were tape printers that spit out a tape with letters on it.   
   Often, the tape had a gummed back so the operator could cut it into strips and   
   stick it to a telegram form, something you may have seen in old movies.   
      
   In addition to public telegrams, there were networks of commercial stations   
   known as Telex and TWX — precursors to modern e-mail. These networks were   
   like   
   a phone system for teleprinters. You’d dial a Telex number and send a message   
   to that machine. Many teleprinters had an internal wheel that a technician   
   could set (by breaking off tabs) to send a WRU code (who are you) in response   
   to a query. So connecting to the Hackaday Telex and sending WRU might reply   
   “HACKDAY.” In addition, you could ring a bell on the remote machine. So a   
   single bell might be a normal message, but ten bells might indicate an urgent   
   message.   
      
   Word Processing   
      
   While replacing telegraphs was an obvious use of teleprinter technology, you   
   might wonder how people could use these as crude word processors. The key was   
   the paper tape and a simple paper tape trick. A Baudot machine would have five   
   possible punches on one row of the tape. You can think of it as a binary number   
   from 00000 (no punch) to 11111 (all positions punched out). The trick is that   
   if all positions are punched out, the reader would ignore that position and   
   move on to the next character. They also usually had a code that would stop the   
   reading process.   
      
   This allowed you to do a few things. First, you could punch a tape and then   
   make many copies of the same document. If you made a mistake, you could   
   overpunch the tape to remove any unpunched holes and “delete” characters.   
   It   
   was also common to use several fully punched-out characters as a leader or a   
   trailer, which allowed you to line up two tapes and paste them together.   
      
   So, to insert something, you could identify about a dozen characters around the   
   insert and over-punch them. Then, you’d prepare another tape that had the new   
   text, including the characters you punched over. You’d start that tape with a   
   leader and end it with a trailer of fully punched positions. Then, you can cut   
   the old tape and splice the new tape’s leader and trailer over the parts you   
   punched out in the first step. A lot of work? Yes, but it’s way better than   
   retyping everything by hand.   
      
   Once you create your master tape, you could turn out many originals. You could   
   even do a sort of mail merge. Suppose I have a form letter reminding you to pay   
   your bill. The master tape would have a pause in key places. So, the operator   
   would do something like type the date, name, and address. Then, they would   
   press start. The tape would type “Dear ” and then read a stop code. The   
   operator could type the name and press start again. Now, the tape would run up   
   until a later point, and another stop code would let the operator enter the   
   account number and press start again. The next stop might be for the balance   
   due, and a final stop for the due date. Pretty revolutionary for the 1940s.   
      
   Really high-tech installations used two tapes, one loop with the form letter   
   and another unlooped tape with the input data. The operator did almost nothing,   
   and all the letters were printed automatically.   
      
   [image 6][6]An ASR-33 (CC-BY-SA-3.0[7] by [ArnoldReinhold])Of course, not all   
      
   [continued in next message]   
      
   --- SoupGate-DOS v1.05   
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