Owner manual / English
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Casio Module 308 Manual
Two owner's manual PDFs for the Casio module 308, each a different scan (English included). Casio's spec sheet lists one 399, with 3 years of battery life and accuracy within ±15 seconds a month; the module first shipped in Feb 1986.
Module specs
Battery: 399 (silver-oxide)
Rated battery life: 3 years
Rated accuracy: ±15 sec/month
Casio service manual ref: S/M-195
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