It broadcast to the southern province of Sweden, Skåne, and was run by a young man, Nils-Eric Svensson, who had studied radio and TV in the USA and had worked at the government-run Swedish Radio for a very short time.
It was later accompanied by the larger Cheeta II, placed in Storebaelt between Zeeland and Fuenen in order to cover most parts of Denmark.
The two stations merged in January 1962 and continued under the name Radio Mercur but with the jingle from DCR.
The Danish parliament decided on a bill in June 1962, that effectively prohibited all participation in activities supporting transmissions, recordings, etc.
The final song played was Auld Lang Syne by Mitch Miller.
In Sweden the station Radio Syd, using two of Mercur's former ships in succession, succeeded transmissions up to 1966 in defiance of the law.