Sony's Transistor Radio: Portable Sound Is Born
Tokyo Tsushin Kogyo (Tokyo Telecommunications Engineering Corporation) released its first transistor radio, the TR-55, in Japan on August 7, 1955. The company had licensed transistor technology from Western Electric for $25,000 and spent two years figuring out how to mass-produce high-frequency transistors reliably. The TR-55 was small enough to fit in a pocket, ran on batteries, and cost a fraction of a vacuum tube radio. It flopped domestically because Japanese consumers preferred larger models. But the company's export-focused follow-up, the TR-63, became an international sensation. The company changed its name to something easier for English speakers to pronounce: Sony. The transistor radio launched the portable electronics revolution.
August 7, 1955
71 years ago
Key Figures & Places
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