Radio Caroline will broadcast on the former BBC World Service medium wave frequency of 648 kHz, after being awarded a community radio licence for East Anglia.
The station was given the go-ahead by Ofcom last month, and now says the regulator has also agreed to its request for a 1000-watt transmitter.
In a statement on the Radio Caroline website, the station said: “We can now announce that our AM frequency will be 648 kHz with a power of 1000 watts. This is ERP or simply the power radiated by the aerial.
“A transmitter was imported from the Continent a few days ago and is now being modified to suit the frequency. There are further hurdles, but as you can see progress is being made. Watch this space.”
The new Radio Caroline will play album tracks and had proposed a coverage area from Ipswich to Diss and Bury St Edmunds to Saxmundham. Some programmes will be broadcast from studios in Kent, and others via a link to the Ross Revenge ship. The station has previously said that, if practical, it aims to get on air in time for the 50th anniversary of the Marine Offences Act on 14th August.
Caroline already runs a service online and via a number of DAB multiplexes around the country.
The BBC World Service was broadcast on 648 kHz from Orfordness in Suffolk between September 1982 and March 2011.