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First television underwater

First television underwater
Who
19th National Radio and Television Exhibition
What
First
Where
London
When
26 August 1952
The earliest public demonstration of underwater TV occurred on the 26 August 1952 at the 19th National Radio and Television Exhibition, London, UK.  Marconi Siebe Gorman showed model divers working on the stern of a sunken ship on monitor sets. The cameras used to film the divers weighed 900 kg (1,984 lb), cost £3,500 ($6,400) and could transmit pictures from 455 m (1,492 ft).

Marconi Siebe Gorman was a coalition - Marconi for TV, Siebe Gorman are historically linked with aqualungs.