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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†

Some images of technical manuals can be seen in Technical

Date code†

• 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†

I would be grateful to receive information, especially the early 550 and 570 watches.

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