I read about St GIGA in David Toop’s OCEAN OF SOUND: “Devised in 1990 by Hiroshi Yokoi, a pioneer of twenty-four-hour FM radio transmission in Japan, St GIGA was the first Japanese satellite station.”
In accordance with Yokoi’s conception, St.GIGA’s broadcasts initially followed no externally fixed (or artificial) timetable. Rather, they were based upon the cyclical motif of a 24-hour “tide table“[4] where broadcast themes were approximately matched to the current tidal cycle according to the rule of twelfths throughout the 24-hour broadcasting period. Under this innovative schedule, the station broadcast a variety of primarily ambient music programs including Music Tide (音楽潮流, Ongaku Chōryū), various jazz programs, and Tide Table (タイド・テーブル, Taido . Teburu) (featuring live sound-broadcasts of the ocean shore). The beginnings and ends of programs were not clearly demarcated and instead utilized the unprecedented “Tide of Sound” (音の潮流, Oto no Chōryū) method where songs of one genre would gradually flow into and intersperse with the songs from the prior genre until the new genre became predominant. The intent, according to Yokoi was to allow the listener to relax in a wave of sound “like a baby sleeps in the womb.”[4]
On Archive.org, I found a single sixteen-hour block of St GIGA broadcast.