My father set to work to design sufficiently sensitive equipment and eventually developed "aperiodic" direction-finding. This enabled the bearing of the wanted signal to be accurately identified among the mass of other interfering signals. It took several years to become operational but eventually became an important weapon in the war against the U boats. Even today all direction-finding equipment is "aperiodic."
In 1915, before the system was fully operational, my father suggested to Hall that the best solution was to locate a direction finder in Christiania (now Oslo). Norway at this time was neutral, but the British Embassy could not be used for fear of alerting the Germans, so Hall asked my father if he was prepared to go and run the station clandestinely for MI6. Within days he was on his way to Norway, posing as a commercial traveler trading in agricultural medicines. He set up in a small hotel in a side street in Christiania and rented an attic room high enough to rig direction-finding wireless without being conspicuous.
The MI6 station in the Embassy supplied him with communications and spare parts, but it was dangerous work. His radio equipment was bound to give him away eventually. He was not part of the diplomatic staff and would be denied if discovered. At best he faced internment for the rest of the war, at worst he risked the attentions of German Intelligence.
The operation ran successfully for six months, giving the Navy invaluable early warning of German Fleet intentions. Then one morning he came down to breakfast at his usual table. He looked casually across the street to see a new poster being pasted onto the wall opposite. It was his photograph with an offer of a reward for information leading to his arrest.
He had worked out his escape route with MI6 before the operation began. He quickly finished his breakfast, returned to his room, carefully packed his wireless equipment in its case and pushed it under the bed. He gathered up his travel documents, passport, and Naval identity card, leaving a substantial quantity of cash in the hope that it might encourage the hotelier to forget about him.
Rather than taking the road toward the Swedish coast which the Norwegian authorities would assume to be his most likely escape route, he set off to the southwest. Ten miles down the coast he sat down on a rock by the roadside. Sometime later, a British Naval lieutenant walked up to him and asked him who he was. Father identified himself and he was taken to a launch and ferried out to a waiting British destroyer.
Years later, when I was coming up for retirement, I tried to find the details of this operation in the MI6 files. I arranged with Sir Maurice Oldfield, the then Chief of MI6, to spend the day in their Registry looking for the papers. But I could find nothing; the MI6 weeders had routinely destroyed all the records years before.
I was born in 1916 at my grandmother's house in Chesterfield, where my mother had gone to stay while my father was in Norway for MI6. There was a Zeppelin raid on nearby Sheffield that night, and I arrived very prematurely. There were no hospital beds available because of the pressure of the war, but my mother kept me alive with an improvised incubator of glass chemical jars and hot-water bottles.
After World War I my father rejoined the Marconi Company. He became a protege of Marconi himself and was made Head of Research. We moved to a large house by the sea near Frinton. But this lasted only a few months, when we moved to a house on the outskirts of Chelmsford. The house often resembled a disused wireless factory. Radios in various states of disrepair and tin boxes filled with circuitry were hidden in every corner. My father was an intense, emotional, rather quick-tempered man - more of an artist than an engineer. As early as I can remember he used to take me out into the garden or onto the open fields above the Essex beaches to teach me the mysteries of wireless. He spent hours explaining valves and crystals and showed me how to delicately turn the dials of a set so that the random static suddenly became a clear signal. He taught me how to make my own experiments and I can still remember his pride when I demonstrated my crude skills to visiting guests like Sir Arthur Eddington and J. J. Thomson.
MI6 had close connections with the Marconi Company after World War I, and my father retained his contact with them. Marconi had a large marine division responsible for fitting and manning wireless in ships. It provided perfect cover for MI6, who would arrange with my father to have one of their officers placed as a wireless operator on a ship visiting an area in which they had an interest.
Admiral Hall was a visitor to the house; he and my father would disappear into the greenhouse together for hours at a time to discuss in private some new development. My father also knew Captain Mansfield Cumming, the first Chief of MI6. He admired Cumming greatly, for both his courage and his technical ability. He knew Captain Vernon Kell, the founder of MI5, much less well, but did not like him. As with Oxford and Cambridge, people are usually disposed either to MI5 or to MI6, and my father very definitely leaned in favor of MI6.
The Marconi Company during the 1920s was one of the most exciting places in the world for a scientist to work. Marconi, known to everyone by his initials, "G.M.," was a superb picker of men, and had the courage to invest in his visions. His greatest success was to create the first shortwave radio beam system, and he can justly claim to have laid the foundations of modern communications. As with so many British achievements, it was done against the opposition of the British Government and the top scientists of the day.
Before World War I Britain decided that a long-wave radio system should be built to replace the cable system as the principal means of communication with the Empire. The decision was held in abeyance during the war. But Marconi believed it was possible to project short wavelength transmissions over vast distances using beams. The use of shortwave beams promised a greater volume of traffic at much higher speeds. Despite the advances in wireless made during the war, Marconi's vision was derided as "amateur science" by a Royal Commission in 1922. One member even concluded that radio was "a finished art."
Marconi issued a challenge. He offered to build, free of charge, any link across the world - provided the government would suspend long-wave development until the beam system had passed its trials, and provided they would adopt it if the trials were successful. The government agreed and specified the toughest contract they could devise. They asked for a link from Grimsby to Sydney, Australia, and demanded that it operate 250 words a minute over a twelve-hour period during the trials without using more than twenty kilowatts of power. Finally they demanded that the circuit be operational within twelve months.
These were awesome specifications. Radio was still in its infancy and little was known about generating power at stable frequencies. The project would have been impossible without the commitment of the Marconi technical team, consisting of my father, Captain H J Round, and C S Franklin. Marconi had a special talent for finding brilliant scientists who were largely self-taught. He found Franklin, for instance, trimming arc lamps in an Ipswich factory for a few shillings a week. Within a few years he rose to become the outstanding technical man in the company.
The proposed Grimsby-to-Sydney link astonished the rest of the radio communications industry. My father often described in later years walking down Broadway with David Sarnoff, the then head of RCA, when the project was at its height.