Casio CSN-003 / CSN-010 Manual — Module 1634

Two owner's manual PDFs for the Casio module 1634, each a different scan. Casio fitted it in the CSN-003 and CSN-010. Casio's spec sheet lists one CR1220, with 18 months of battery life and accuracy within ±15 seconds a month; the module first shipped in Oct 1997.