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Casio BG-390 Manual — Module 1657

One owner's manual PDF for the Casio module 1657 in English. Casio fitted it in the BG-390. Casio's spec sheet lists one SR1120W and a SR621W (for EL) backup cell, with 15 months of battery life and accuracy within ±15 seconds a month; the module first shipped in May 1997.

Module details

Brand: Casio

PDF files: 1

Released: May 1997

Mapped models: 1

Module specs

Battery: SR1120W (silver-oxide)

Backup cell: SR621W (for EL)

Rated battery life: 15 months

Rated accuracy: ±15 sec/month

Casio service manual ref: S/M-554

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Owner manuals

Watch models using this module

ModelReleased
BG-390-