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Casio Module 21 Manual

One owner's manual PDF for the Casio module 21 in English. Casio's spec sheet lists one 393, with 15 months of battery life and accuracy within ±15 seconds a month; the module first shipped in Oct 1977.

Module details

Brand: Casio

PDF files: 1

Released: Oct 1977

Mapped models: 0

Module specs

Battery: 393 (silver-oxide)

Rated battery life: 15 months

Rated accuracy: ±15 sec/month

Casio service manual ref: S/M-104

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Owner manuals