Information / Radiohistory for Japan
Beginning of Radio Broadcasting in Japan
Before the Broadcasting
Japan has a long history of researching wireless communication as well as its home production. Three years after the experiment on yield of current by Herz (1886), Hantaro Nagaoka made public experiment in spark discharge at The University of Tokyo(1889). Just after Marconi's wireless communication in 1887, research started for practical use by Electrotechnical Laboratory in Japan.
In 1899 began home products of wireless equipments. Thus wireless equipments realized excellent results at the Battle of the Japan Sea in 1914. After the WW I, wireless were used very often, not only for military use but also for marine use.
In 1914, with regard to this situation, the Wireless Law and the Reguration for Private Wireless Telegraph were enacted.
In 1920, KDKA Station in U.S.A. started world first broadcasting. Also in Japan research on broadcasting became much popular, and various experiments were extensively carried on. Consequentry many technical books, eriodicals and magazines were published. By confusion of the Kanto Earthquake Disaster in 1923, information routes were cut off. But ships anchored in Tokyo Bay gave the most effective results communicating by wireless. Consequently public opinion were aroused for realization of broadcasting.
Beginning of Broadcasting
In the next year after the Earthquake, applications for establishing broadcasting station were estimated to reach 64 throughout the land. But Japanese government set limits and sanctioned the establishment of broadcasting stations running by public utilities corporations in three great cities, Tokyo, Osaka, Nagoya. In 1924, Tokyo Broadcasting Station (JOAK), in 1925 Osaka Broadcasting Station (JOBK) and Nagoya Broadcasting Station (JOCK) were established. All of them were corporation aggregates. On 22 March, 1925, radio broadcasting started provisionally from Shibaura Broadcasting Station in Tokyo, which was the beginning of Japanese history of radio broadcasting. Only 5 years behind the world first broadcast in U.S.A. Although the number of listeners of was no more than 5,455 at that time, it jumped to 390,000 by 1926.
Radios at the beginning of broadcasting
Under the ordinance the Regulation for Private Wireless Telephone promulgated in 1923 just before the beginning of broadcasting, radios were admitted as obtained sanction from the Communication Ministry. Technical standard was set on the basis of the ordinance "The Regulation for Electrical Appliance", Article 4 of the Communication Ministry issued in 1916, and it is decided that the wave length must be confined within 200-250m or 250-400m, besides radio waves must be without generation from antenna. Whoever passed examination acquired "The Type Approval" and could indicate passing number as well as type approval stamp (created in 1924). As for approved receivers, wave-length selector was required, and besides generation of radio wave was permitted. Thus, regenerative detector could not be used, the sensitivity was low, therefore expensive. But in reality, lots of imported and hand-made radios not always following such ruled ware used.
On 18 April, 1925 just after the beginning of broadcasting, Ordinance No.23 of the Communication Ministry was issued, which abolished selector of wave length and limited wave length less than 400m. In addition to it, permission for listening was given to non approved radios. Accordingly, type approval system became nominal. After Ordinance No.71 of October 1925 now on, no more than examination was carried on. Through 1924 into 1925 type approval was given to 64 varieties of radios and parts, of which from No.2 to No.71 (No. 1,6,1,12,13,35,36 missing) are in existence. Makers of communicating equipment such as Annaka and Shibaura which had produced lots of approved receivers withdrew from radio industry several years after the beginning of broadcasting. 70% of Japanese radios at that time were crystal type listening worth receivers. Battery operated tube radios using loud speaker system were not only expensive but also had to equip three types (A, B, C) of battery, especially by using Lead-acid battery for "A" lighting filament, the work required much time to charging.
Consequently not of public use. Japan introduced technique and appliances of radios from U.S.A. At first triode tube UV-201 ware used. Later, 201-A type with filament current reduced by half or power economized type 199 were used. As the result of that, A type battery could be changed from Lead-acid battery to dry battery. Therefore, since about 1924 much of radio sets have contained batteries inside.
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