Magneto Switching System belonging to NTT History Center of Technologies has been registered as "Essential Historical Materials for Science and Technology" by the National Museum of Nature and Science

Nippon Telegraph and Telephone Corporation (NTT; Head Office: Chiyoda-ku, Tokyo; President & CEO: Jun Sawada) is honored to announce that the magneto switching system which is owned by the NTT History Center of Technologies has been registered as "Essential Historical Materials for Science and Technology" by the National Museum of Nature and Science on 21st August 2018. Not only its value as the historical asset that shows the development history of science and technology in Japan, its condition and the effort to maintain the function at the time of manufacturing is highly evaluated.
In 1890, when telephone service began in Japan, magneto switching systems had been used. Telephone operators had used them to connect phones each other by operating cables by hand. The magneto switching system was useful machine in the early days of telephony in Japan. The switching system made it possible to realize the flow; "Calling" to make a phone call, "Switching" to connect phone and phone, "End talk" to finish talking.

In the 1920s, the demand for telephone had rapidly increased, therefore automatic switching systems had been introduced, especially after Nippon Telegraph and Telephone Public Corporation (NTT's predecessor) founded, the R&D around automatic telephone switching had been accelerated. Even after the automatic switching systems had been installed, the magneto switching systems had still played important role of telephone switching in rural area for a long period.

NTT History Center of Technologies and HCT Volunteers repaired and have maintained a magneto switching system which was actually used for telephone switching service, to make an exhibit in Hands-on Corner. The center has contributed to transfer the structure, method and principle of the various telephone and switching systems, the technologies of telecommunication to the followers, and has offered valuable opportunities to experience the operation and flow of manual telephone switching.

The Magneto Switching System (NTT History Center of Technologies)