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Dating Japanese equipment.

Ernst Erb Jürgen Stichling Bernhard Nagel 
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Forum » Radio- and technical History » Technical history: 1920 and later » Dating Japanese equipment.
Maarten Bakker
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28.Jan.15 00:48

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When encountering a round ink-stamp which reads 38.9.27 on the variable capacitor of Ying NTR-223, I was reminded of this system of date-coding and thought it useful to mention it here as it can be a good aid in dating Japanese equipment.

The format is YY.MM.DD in which YY starts counting at 1 on the start of the reign of a new emperor as follows:

Meiji era = 1868-1912
Taisho era = 1912-1926
Showa era = 1926-1989
Heisei era = 1989-present

Which results in 38.9.27 representing 27 september 1963 in our system (1949 being implausible for a small transistor set).


John Wolff and various posts on

Georg Richter
Georg Richter
D  Articles: 916
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28.Jan.15 01:27

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For "modern" Japanese equipment with integrated circuits, this information (german language) should be also mentioned.

Best Regards,