Geoffrey joined the navy in 1921. In 1929, he trained as a specialist in Radio and Communications at Signals School. He progressed well in his career and was extremely organised in his observations. Notebooks by Geoffrey show meticulous handwriting with beautiful diagrams and enormous attention to detail.
In the 1930s (while he was serving in the Home and Mediterranean Fleets) Geoffrey met his future wife, Daphne Parry. At the time he was Flag Lieutenant to Captain (later Admiral) Parry who had married Violet Beatrice Waymouth in the Anglican Cathedral, Valletta, Malta.
Geoffrey and Daphne were married on 13th November 1931 at St Jude's Church in Southsea, Hampshire and went to live in Festing Road, Southsea, where Daphne's parents then lived. In 1936, the family moved to 30 Villiers Road, Southsea, which was to become their family home for the short time (9 years) that Daphne still had to live. In 1939, at the outbreak of war, Geoffrey was finishing his service working as flag lieutenant on the two aircraft carriers HMS Courageous and HMS Ark Royal, and starting as a signals lieutenant in the dockyard in Portsmouth. Geoffrey had by this time taken a signals course on which Louis Mountbatten, the Queen's uncle, was an instructor. Lord Louis and Geoffrey had long-lasting relationship, which continued through (at least) Christmas Cards until Geoffrey's death. Geoffrey was also senior wireless instructor at the HM Signals School.
In 1942 Geoffrey took part in the Malta Convoy on board HMS Victorious, and received a citation for bravery and exceptional devotion to duty. In 1943 he became Executive Commander of HMS Berwick. At one stage during the war, in 1944, as officer in charge of Radio and Radar planning for the Admiralty, Geoffrey was sent to the USA, as a Commander RN.
When Daphne was taken ill in Southsea in 1944, Geoffrey was working at the Admiralty in London. Daphne died on 1st January 1945. She and Geoffrey had one child, a daughter. In 1946 Geoffrey married Iris Mary Cooper, nee Mason and they had three children.