Owner manual / English
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Casio Module 304 Manual
One owner's manual PDF for the Casio module 304 in English. Casio's spec sheet lists one SR920W, with 2 years of battery life and accuracy within ±15 seconds a month; the module first shipped in Nov 1989.
Module specs
Battery: SR920W (silver-oxide)
Rated battery life: 2 years
Rated accuracy: ±15 sec/month
Casio service manual ref: S/M-317
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