1955 · Japanese Transistor Radio · Work 827 of 1,871
A transistor radio of 1955 being assembled on a workbench in a small radio factory in Tokyo in summer, a pale green plastic case fourteen centimetres wide lying open with its back upward, inside it a brown circuit board with five small metal cylinders on wire legs, in front a flat wooden box with twelve compartments full of tiny coils, each row with a different dot of colour, hands in white cotton sleeves holding a coil with tweezers above the board, a soldering iron in its stand, window light from the left.
What it was used for
Tokyo Tsushin Kogyo put the TR-55 on the Japanese market in August 1955, a superheterodyne receiver with 5 transistors. Its high-frequency transistors came from a project of its own: the Semiconductor History Museum of Japan names a project for high-frequency transistors for radios under Tetsuo Tsukamoto. The licence came in 1953 from Western Electric, which held the transistor patent. The price was 18,900 yen - the museum's Makimoto Library adds that the starting salary of college graduates was between 7 and 8 thousand yen. When Ibuka decided in 1952 to work on transistors, the company had only about 200 employees, by the same account.
What was new
The Japanese sources themselves say what the TR-55 was not. The Semiconductor History Museum of Japan writes that Sony's TR-55 was not the first transistor radio in the world; the "world first" had been sold by Regency of the United States about half a year before, and the company had to put down the signboard of "the First in the World". What differs is the construction: 5 transistors in a superheterodyne against the 4-transistor set from the United States, and the deliberate choice of grown-type transistors despite their low manufacturing yield. The predecessor never reached the shops: the TR-52 prototype was finished in January 1955, but in the summer of 1955 the lattice-shaped plastic panels of the cases lifted in the heat and the model was not launched - it is referred to as the phantom of the United Nations building type radio.
What the sources leave open: Yield is described only qualitatively, with phrases such as poor yield and, at times, zero yields; no source opened gives percentages. Unit numbers, sales figures, weight and the size of the Western Electric licence fee are not documented. The Japanese museum pages do not name the Regency model by type number. Per the exhibit PDF, Kobe Industry announced the first transistor radio in Japan as early as January 1954 but did not commercialise it.
Connections
Every connection names its kind. “Forerunner” on its own would be a claim.