Owner manual / English
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Casio Module 303 Manual
One owner's manual PDF for the Casio module 303 in English. Casio's spec sheet lists one 370, with 2 years of battery life and accuracy within ±20 seconds a month; the module first shipped in Oct 1982.
Module specs
Battery: 370 (silver-oxide)
Rated battery life: 2 years
Rated accuracy: ±20 sec/month
Casio service manual ref: S/M-135
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