Numerical Printing Telegraph

A numerical printing telegraph is a device that encodes incoming information and prints it as numerals on tape.OKI's numerical printing telegraphs were used for aeronautical information processing. To be specific, they printed the direction of approaching airplanes, time, models, the number of airplanes, etc. as numerals on paper tape. In addition, they switched on the indicator lamp(s) showing the approach of an airplane on a map by controlling electric contacts.

Going back in history, the telegraphic communication was started with electrical communications for text messages, and the most famous method is the Morse telegraph. The Morse telegraph is inconvenient as it requires generation of pulses at transmission and decoding of text messages at reception. To cut out such work, a printing telegraph was developed. The emergence of a printing telegraph, which generates pulses and decodes text messages by itself, brought not only extremely-simplified character-to-character transmission but also communications using letters and characters.

OKI started investigation on and manufacture of printing telegraphs as long ago as 1932 with a simplified printing telegraph. During mechanization of the telegraph relaying process as a communication infrastructure, OKI made a great progress in 1950 as a result of fusion of the telephone switching technology and printing telegraphs. This product was the foundation for the telegraphic communication technology that developed after that time and led to teletypewriters.