Teletype Corporation
Charles Underhill invented an early teleprinter in the early 1900's. Clifford Babcock, Lee de Forests’ engineer, gave him an early de Forest Audion vacuum tube, with which he tried to improve his machine. Despite his best efforts, Underhill was unable to create a practical teleprinter, and gave the Audion to Howard Armstrong, a high-school student that lived in the area, who would go on to discover regeneration and invent the super-hetrodyne and FM circuits used in all modern radio equipment.
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At about the same time as Underhills' effort, a young electrical engineer named Frank Pearne was experimenting with a printing telegraph system and approached Joy Morton, of the Morton Salt Company, for financial support. Morton discussed the matter with his friend and mechanical engineer, Charles Krum, who was vice president of the Western Cold Storage Company, which was operated by Joys' brother Mark. The decision was favorable to Pearne, and he was given laboratory space in the attic of Western Cold Storage.
Pearne lost interest in the project after experimenting unsuccessfully for a year, but Charles Krum continued the work and by 1906 had developed a promising model. In that year, his son Howard Krum was graduated as an electrical engineer and joined the effort alongside his father. Several patents were issued to them from 1903 through 1908 covering this early effort, but none of their designs used permutation codes.
After having experimented with their machines on actual telegraph lines, they faced the largest challenge of all, synchronization - keeping the machines "in-step". It was Howard Krum who worked out the start-stop method of synchronization, and the patent was filed in May, 1910 and issued in December, 1918. This acheivement, more than anything else, made printing telegraphy possible, and was first used in their "Green Code" printer in 1909.
The modern keyboard-controlled cam-type start-stop permutation code transmitter was developed by Charles and Howard Krum in about 1919, and was used in the Morkrum Company Model 12 introduced in 1924. In December of that year, Howard Krum and Sterling Morton (Joys' son) filed a patent application for the Model 14 type-bar printer.
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Ed Kleinschmidt was interested in facsimile and automatic telegraphy, and filed a patent for a Morse keyboard transmitter in 1905, and later for a Morse keyboard perforator. In 1916, he filed a patent for a type-bar page printer which utilized the Baudot permutation code, but was not start-stop. Shortly after Krums' start-stop patent was issued in 1918, Kleinschmidt filed and received a patent for a start-stop version of his Baudot machine.
Kleinschmidts' patent was dominated by the Krum start-stop patent, and the conflict was eventually resolved by a merger of the interests. Soon after the merger, the company was renamed the Teletype Corporation, and filed a patent for the Model 15 Page Printer.
The Teletype Corporation was acquired by the Bell System in 1930. Ed Kleinschmidt quit and formed a competing company which became a major supplier of machines to the military.