Casio MTG-900DJ / MTG-900IDJ Manual — Module 2639

Two owner's manual PDFs for the Casio module 2639, each a different scan (English included). Casio fitted it in 8 models, including the MTG-900DJ and MTG-900IDJ — the full list is below. Casio's spec sheet lists one CTL1616, with 6 months of battery life and accuracy within ±15 seconds a month; the module first shipped in Mar 2003.