The telediphone was an early

sound recording Sound recording and reproduction is the electrical, mechanical, electronic, or digital inscription and re-creation of sound waves, such as spoken voice, singing, instrumental music, or sound effects. The two main classes of sound recordin ...

system, using cylindrical

recording media Data storage is the recording (storing) of information (data) in a storage medium. Handwriting, phonographic recording, magnetic tape, and optical discs are all examples of storage media. Biological molecules such as RNA and DNA are cons ...

. One such system was used from 20 December 1938 at the

US Navy The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage ...

radio intercept station at

Shanghai Shanghai (; , , Standard Mandarin pronunciation: ) is one of the four direct-administered municipalities of the People's Republic of China (PRC). The city is located on the southern estuary of the Yangtze River, with the Huangpu River flowin ...

, to monitor the Moscow-Tokyo diplomatic circuit, using two recorders. In January 1939, this equipment was reported as more successful than automatic recording equipment trialed for the same purpose. The Telediphone Unit was a transcribing department of the BBC using cylinder and other machines, which produced a typed transcript of (primarily) interview recordings. A recording could be ordered by a producer to be fed to the Unit and after a few days would receive a typed copy.Item 153907 of Delia Derbyshire's papers
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References

Sound recording technology {{Sound-tech-stub