NHK transmitted Hirohito’s surrender recording to Japan on 15 August 1945.
NHK was Japan’s national broadcasting organization, then known in English as the Japan Broadcasting Corporation. Its technicians recorded the emperor’s rescript at the Imperial Palace and prepared the recording for transmission across the country.
The speech aired at noon Japan Standard Time. It was replayed from a phonograph record rather than delivered live, because the recording had been made the previous night. A group of military officers tried to stop the announcement during a failed coup attempt, but the recordings were hidden and ultimately reached the NHK station.
The broadcast was historically significant because ordinary Japanese people had not previously heard their emperor speak publicly. The formal language was difficult for many listeners, and the address did not use a direct phrase equivalent to “Japan surrenders.” NHK announcers therefore helped explain the meaning after the recording ended.