Following the invention of the transistor in 1947, along with Maddock's application of electronic instruments, he obtained measurements of the speed of detonation and time of the projectiles' flight with greater accuracy.

[2] Maddock was made an Officer of the Order of the British Empire in the 1953 New Year Honours,[3] having been crucial to the success of firing and collecting data on the Operation Hurricane atomic bomb test in the Monte Bello Islands on 3 October 1952.

[2] Maddock was appointed Head of the Field Experiments Division of the Atomic Weapons Research Establishment in 1960, ensuring a continued role in British bomb tests of the 1950s and 1960s.

In order to attain political control of nuclear explosions, such equipment would be required in multitudes, resulting in the 1973 Partial Test-Ban Treaty, which was signed by 150 countries.

In this role, Maddock worked on engineering improvements and developing technical skills in design and manufacture, but was often frustrated by unreasoning resistance to change among British management and workers, and within the Civil Service itself.

He produced various publications in academic journals and was thus a visiting professor at Imperial College London from 1977 to 1979, and secretary of the British Association for the Advancement of Science from 1977 to 1981.