NHK transmitted Emperor Hirohito's surrender address on August 15, 1945.
NHK was then known as the Japan Broadcasting Corporation and served as Japan's national radio broadcaster. The emperor's recorded rescript was broadcast nationwide at noon Japan Standard Time. The address became known as Gyokuon-hōsō, or “Jewel Voice Broadcast.”
NHK technicians recorded Hirohito at the Imperial Palace the night before the transmission. The recording was not a live speech. Palace officials and military officers feared that opponents of surrender might seize or destroy the recording, and an attempted coup took place during the night of August 14–15.
The broadcast was difficult for many listeners to follow. Hirohito used formal Classical Japanese, and the audio quality was poor. The speech also described acceptance of the “joint declaration” rather than using a plain modern phrase announcing surrender. Nevertheless, the NHK transmission made the emperor's decision known across Japan.