It was originally intended that programmes would begin on 15 July 1973, using "Mi Amigo"s 10-kilowatt transmitter on 773 kHz (388 metres, announced as 385). In readiness for this Atlantis adopted a postal address of Postbus 385, Oostburg, which remained the station's address throughout its lifetime. This plan went awry when it was discovered that "Mi Amigo"s 773 kHz transmitter crystal had gone missing. The crystal, which was about the size of a matchbox, had been used as a replacement pawn for the ship's chessboard, and had apparently been thrown overboard when the chess set was replaced. Consequently, when Radio Atlantis launched it was on "Mi Amigo"s 50 kilowatt transmitter, on Caroline's main frequency of 1187 kHz (253 m), although all of the DJ announcements originally gave the wavelength as 385. It has been claimed that Atlantis was the only offshore radio station ever to launch on its announced date, even though it was on the wrong frequency.