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Ricoh Watch Co., Ricoh Keiki Co. Ltd., リクォーツ - Unofficial Riquartz Database

[[Analog]] watches

[[Digital]] LCD & LED watches

[[Combination]] analog/LCD

[[Correct Time Receiver]]

[[Quartz Timer]] timing & testing machine 

*Technical [#o188fe31]
Some images of technical manuals can be seen in [[Technical]]

*Date code [#le1f8c99]
-Stamped inside caseback; Year & 1-9 then XYZ, example "75-2" = Feb 1975, "77-Y" = November 1977

-Some watches also have a code in addition, which looks like the date in the Showa calendar, but which does not correlate with the date code above.

-Some early [[CMOS IC]] chips use the EIA date system, ie marked 7421 means 21st week of 1974.

-Quartz cannisters can be marked, ie NDK 76F is June 1977.

*Information [#m058fc4a]
I would be grateful to receive information, especially the early [[550]] and [[570]] watches email to: jr AT umddb DOT net
I would be grateful to receive information, especially the early [[550]] and [[570]] watches.




https://pukiwiki.sourceforge.io