GBR is 75. Special VLF transmission.
This information from G4KHU:-
"Listeners may be aware that the UK Royal Navy are celebrating the Centenary of the Royal Navy Submarine service with a gathering of UK and overseas submarines in the Clyde. This year is also the 75th anniversary of operation of the GBR transmitter (Rugby).
As part of this celebration 'It is hoped' that a special A1A Morse code transmission from the GBR long wave transmitter will be made. For those with an interest in VLF reception please listen to 16kHz (yes 16 > not 60kHz!) on Tuesday 29th May 2001 at 1200GMT and 1345GMT."