Casio CA-851 / CA-90 Manual — Module 134

One owner's manual PDF for the Casio module 134 in English. Casio fitted it in 4 models, including the CA-851 and CA-90 — the full list is below. Casio's spec sheet lists one SR1130W, with 15 months of battery life and accuracy within ±15 seconds a month; the module first shipped in Apr 1981.