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RNI - Key Dates

















22nd January 1970

Mebo II left Rotterdam and anchored off Noordwijk on the Dutch coast

23rd January 1970       

Test transmissions for Radio North Sea International (RNI) started on short wave and on FM

11th February 1970

Tests on the medium wave frequency of 1610kHz (186m) started  

26th January 1970

The Panamanian Consul in Rotterdam was reported to have removed the Mebo II from his country's maritime register

28th February 1970

Regular programming from RNI starts at 6.00pm

23rd March 1970

Mebo II leaves her anchorage off the Dutch coast and heads towards England

24th March 1970

Mebo II anchors off Clacton on Sea, Essex

10th April 1970  

After 10 days silence RNI returns on 102mHz FM as well as a new medium  wave frequency of 1578kHz (190m)

15th April 1970

In an unprecedented peacetime move the British Ministry of Posts and Telecommunications authorises the official jamming of RNI's medium wave signal on 190m  

30th April 1970

Test transmissions on a new frequency of 1385kHz (217m) and also on a new FM frequency of 100mHz start

1st May 1970

The 217m broadcasts were discontinued and the medium wave transmitter remained silent for nearly two weeks

13th May 1970  

Test transmissions of RNI's programmes on 1230kHz (244m)

1st June 1970

RNI’s German language service closed.

13th June 1970

RNI starts using the call sign Radio Caroline International and mounts an anti-Labour Party campaign ahead of the British General Election on 18th June 1970

16th June 1970  

British (Labour) Prime Minister Harold Wilson personally authorises the use of the most powerful transmitter in Europe - a one megawatt facility kept for use in a national emergency - to jam RNI's signal

18th June 1970

Conservative Party unexpectedly win the British General Election

19th June 1970            

RNI dropped the Radio Caroline call sign - its objective of putting the Labour Party out of power had been achieved

28th June 1970

Frequency changed to 1385kHz (217m),  but the jamming followed

30th June 1970

RNI reverts to 1230kHz (244m)

3rd July 1970

The shortwave signal on 6210kHz (49m band) jammed by the Norwegian Rogaland coastal maritime radio station

14th July 1970  

The British Minister of Posts and Telecommunications announced in Parliament that, contrary to assurances given by his party before the June General Election, the jamming of RNI's signal would now continue indefinitely

23rd July 1970

Broadcasts cease and the Mebo II raises her anchor and sails back to Holland

24th July 1970  

Mebo II anchors off Scheveningen and RNI recommences broadcasts

31st July 1970  

All transmissions from the Mebo II were stopped

3rd – 5th August 1970

RNI returns on new medium wave (AM), shortwave and FM frequencies

23rd August 1970

Further medium wave (AM) and FM frequency changes

26th August 1970

RNI tender, Mebo I, arrested and chained up in Scheveningen Harbour as the result of court action taken by Kees Manders who claimed he was owed money by RNI

29th August 1970

A launch  accompanied by a tug come alongside Mebo II and Kees Manders  threatens to cut the anchor chain and tow in the radio ship. DJs make dramatic appeals over the air for listeners to telephone the station's head office in Zurich

22nd September 1970

A separate 'World Service' programme starts on 9940kHz (31m band) shortwave

23rd September 1970

RNI's Swiss owners instruct the radio crew to close the station the following morning

24th September 1970

RNI ceases transmissions at 11.00am. Mebo II remains at anchor – rival offshore station Radio Veronica had paid RNI to close and placed their own Captain and crew on the Mebo II

** December 1970

RNI's directors attempt to repay Radio Veronica so that they can recommence transmissions from the Mebo II, but Radio Veronica's management refuse to accept the money

Back to RNI

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High jacking attempt announcements 29th August 1970

Hijacking announcements August 1970.mp3

Announcing the closure of RNI on 24th September 1970

RNI - announcing first closure.mp3

Announcement of name change to Radio Caroline 13th June 1970

RNI - announcing name change to Caroline.mp3

First test transmission 23rd January 1970

RNI First test transmission.mp3

Arrival off English coast, 24th March 1970

RNI arriving off English coast.mp3

Test transmission on 217m

RNI tests on 217m.mp3

Test transmissions on 244m

RNI test on 244m.mp3

Apology about jamming signal

RNI apology for jamming signal.mp3

World Service ID

RNI World Service ID.mp3