Radio Atlantis appeared in 1964, operated by Davitt Kelly from a flat in Mount Street in Dublin. Using a homemade transmitter, Davitt had hit upon a novel way of making up for a lack of studio equipment, that is he had no way of playing records.
Instead he relayed Radio Luxembourg, turning it down and voicing his own links between records!

The station closed in December 1964, fearing a raid from the authorities.

Ministry Warns Radio Pirates Leitrim Observer – January 2nd 1965

Information Resources:- Radio Radio by Peter Mulryan; A Century of Irish Radio by Eddie Bohan