Casio DBC-61 / DBC-610 Manual — Module 676

Two owner's manual PDFs for the Casio module 676, each a different scan (English included). Casio fitted it in the DBC-61, DBC-610, and DBC-62. Casio's spec sheet lists one CR1616, with 2 years of battery life and accuracy within ±15 seconds a month; the module first shipped in Jan 1988.