This essay addresses the concept of technological theory and analyzes its structure and formation through the example of radio technology. The specific features of technological theory expressed themselves not so much in the explanation of natural processes taking place in various devices, as in their practical usefulness for the creation of technological products. The essay also investigates how the ini- tial theoretical scheme of electrodynamics, as formulated primarily in the work of Heinrich Hertz, developed into a similar, but different, structure of radiotechnical theory. The institutionalization of engineering activity in the area of radiotechnical theory began only after the invention of radio and the creation of a new field of industry. Such activity, pioneered by Ferdinand Braun and directed toward the development of various radio devices, provided the impetus for the rise of radiotechnical theory. Two of Braun’s close colleagues, L. I. Mandel’shtam and N. D. Papaleksi, began to develop radio technology in Russia in the spirit of Braun’s ideas. By 1914, the development of communications technology as a technological science had been largely accomplished. In this essay, the history of radiotechnical theory presents a perfect example (an ideal type) of the evolutionary path of technological theory, in which the interaction of theory and experiment in physics served as a starting point for the development of, on the one hand, a new technology and branch of industry, and on the other, technological theory and scientific disciplines.