The Admiralty Signal and Radar Establishment began as the Admiralty Experimental Department that was set up in 1917 at HM Signal School, Portsmouth,[2] to coordinate research work undertaken since 1896 on the Torpedo School ships HMS Defiance and HMS Vernon.

Concern had already arisen in 1940 as regards the vulnerability of the Signal School to Luftwaffe bombing, but a raid in the autumn of 1940 brought matters to a head, and the move was initiated.

In April 1941 the Experimental Department was renamed the Admiralty Signal Establishment (ASE)[3] which, like its predecessors, was primarily focused on communications.

Premises were found in Lythe Hill House, Haslemere, and in August 1941, the ASE became a separate establishment.

However, technological advances during the Second World War necessitated an increase in related fields of research, and in 1948 these were brought under one body, the Admiralty Signal and Radar Establishment at Portsmouth.