Nippon Denki g.k.
Main office: 2 Shikoku-Cho, Shiba-Ku, Tokyo
Tube Plant (1936): Tamagawa Mukai, Shimonuma-Gun, Kawasaki, Kanagawa

Nippon Denki k.k. (after WW2)
Main Office: 5-7-1 Shiba, Minato-Ku. Tokyo
Tube plant: 1753 Shimo-Numabe, Kakahara-Ku, Kawasaki

NEC Corporation - Nippon Denki Kabushiki Gaisha
Tokyo

While the company was first formed in 1899, tube research did not begin until 1931. In 1932 the chief engineer, Dr Shoji Kobayashi, visited Europe to study tube manufacture and spent about a year there. Earliest tubes were made for voltage and power amplifiers as well as repeaters for wired communication. Transmitting tubes were developed in 1933 and these were based on Western Electric and STC designs. The company strove for high quality, high performance and long life in its tubes. World War Two saw the factory bombed and new premises were found. Materials were in short supply and quality of products dropped considerably. Some tube manufacturing processes were moved to the Ohtsu branch factory and later to Niigata. After the War, the US Military engaged the company in tube manufacture for the US Occupation Forces. Pulse transmitting tubes and CRT's were mass produced. This second field of production led to CRT's being made for the TV industry. Other larger transmitting tubes were made for the next 10 years. In the period up to 1950-51 the company continued to make repeater tubes of Western Electric design.