page_title: Teletype Corporation
section_title: Teletype Corporation
hierarchical_section_title: Teletype Corporation / Teleprinter equipment / Teletype Corporation
caption_attribution_description: Teletype Model 28 at the New York Transit Museum
context_page_description: The Teletype Corporation, a part of American Telephone and Telegraph Company's Western Electric manufacturing arm since 1930, came into being in 1928 when the Morkrum-Kleinschmidt Company changed its name to the name of its trademark equipment. Teletype Corporation, of Skokie, Illinois, was responsible for the research, development and manufacture of data and record communications equipment, but it is primarily remembered for the manufacture of electromechanical teleprinters.
  Because of the nature of its business, as stated in the corporate charter, Teletype Corporation was allowed a unique mode of operation within Western Electric. It was organized as a separate entity, and contained all the elements necessary for a separate corporation. Teletype's charter permitted the sale of equipment to customers outside the AT&T Bell System, which explained their need for a separate sales force. The primary customer outside of the Bell System was the United States Government.
  The Teletype Corporation continued in this manner until January 8, 1982, the date of settlement of United States v. AT&T, a 1974 United States Department of Justice antitrust suit against AT&T.
context_section_description: Teletype models and their dates:
  Model 15 (1930)
  The Teletype Model 15 is a Baudot code page printer; the mainstay of U.S. military communications in World War II. A reliable, heavy-duty machine with a cast frame. In 1930, Sterling Morton, Howard L. Krum, and Edward E. Kleinschmidt filed an application for a U.S. patent covering the commercial form of the Model 15 page printer. Approximately 200,000 Model 15 teleprinters were built. The Model 15 stands out as one of a few machines that remained in production for many years, remaining in production until 1963, a total of 33 years of continuous production. The production run was stretched somewhat by World War II — the Model 28 was scheduled to replace the Model 15 in the mid-1940s, but Teletype built so many factories to produce the Model 15 during World War II that it was more economical to continue mass production of the Model 15. The Model 15, in its "receive only" configuration with no keyboard, was the classic "news Teletype" until the 1950s, when the news wire services began to move to TeleTypeSetter feeds. Some radio stations still use a recording of the sound of one of these machines as background during news broadcasts.
  Model 19 (1940)
  The Teletype Model 19 is a Model 15 with an integrated paper tape perforator and a Model 14 Transmitter-Distributor.
  Model 20 (1940)
  The Teletype Model 20 is an upper/lower case Type Bar Page Printer available as a receive only machine or a send-receive machine with four rows of keys, using a six-bit code for TeleTypeSetter (TTS) use.
  Model 26 (1939)
  The Teletype Model 26 is a Baudot code page printer; a lower-cost machine using a typewheel. The platen and paper moved while typing, like a manual typewriter.
  Model 28 (1951)
  The Teletype Model 28 is a product line of page printers, typing and non-typing tape perforator and tape reperforators, fixed-head single contact and pivoted head multi-contact transmitter-distributors, and receiving selector equipment. Regarded as the most rugged machines that the Teletype Corporation built, this line of teleprinters used an exchangeable type box for printing, and a sequential selector "Stunt Box" to mechanically initiate non-printing functions within the typing unit of the page printer, electrically control functions within the page printer and electrically control external equipment. The Teletype Corporation introduced the Model 28 as a commercial product in 1953, after this product had originally been designed for the US Military.
  Starting with the Model 28, Teletype page printer model numbers were often modified by letters indicating the configuration. The configurations, in increasing order of equipment level and cost, were:
  RO – Receive Only, with a printer and no keyboard or built-in paper tape reader or punch
  KSR – Keyboard Send and Receive, with a keyboard and printer, but no built-in paper tape reader or punch
  ASR – Automatic Send and Receive, with a keyboard, printer, and built-in paper tape reader and punch
  Not all models came in all three configurations. Teletype Corporation documents suffixed the configuration to the model number, e.g., "Model 33 ASR" (Model 33 Automatic Send and Receive).  In contrast, some customers and users tended to place the configuration before the model number, e.g., "ASR-33".
  The U.S. military had their own system of identifying the various models, often identifying various improvements, included options / features, etc. The TT-47/UG was the first Model 28 KSR, and while Teletype's designation for the basic machine remained the same over the next 20+ years, the TT-47/UG took on suffixes to identify the specific version. The last TT-47/UG was the TT-47L/UG. The U.S. Navy also assigned some "set" designations using the standard Army/Navy system, such as the AN/UGC-5, a Teletype Model 28 ASR which has a keyboard, printer, tape punch and reader facilities all in one cabinet.
  Model 29 (1950s)
  The Teletype Model 29 is a six-bit machine using an IBM BCD code.  It began as a replacement for Model 20, but apparently there was no market for such a machine, so it was
caption: A Model 28 KSR
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