Sony identifies the TR-55, introduced in 1955, as Japan’s first transistor radio. The manufacturer was then called Tokyo Tsushin Kogyo. Its five transistors were developed in-house, making the radio an important step in the company’s movement from component research to consumer products. Sony’s own history places the transistor prototype in 1954 and full production of the radio in the following year.
The photographed museum replica shows a small rectangular body with rounded edges and a perforated speaker grille. The tuning display and large circular control occupy one end of the front, so the face remains readable as a simple arrangement of listening and adjustment areas. The compact casing gives the technical change a visible form.
Placed beside the Regency TR-1 and Braun T3, the TR-55 shows how several manufacturers approached portable listening in the 1950s. These radios belong to the same shift toward smaller personal objects, but their cases, displays, and controls express distinct approaches to everyday industrial design.
Regency TR-1 transistor radio
