Seiko Digital Quartz A638A A639A Technical Guide
Technical guide for Seiko Digital Quartz watches models A638A and A639A. Covers specifications, circuit block structure, disassembly and reassembly procedures with detailed diagrams, and checking and adjustment procedures including battery voltage, current consumption, water resistance, accuracy, alarm system, speaker block condition, and bulb replacement instructions.
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Document Details
- Format
- Pages
- 5
- Size
- 259.6 KB
- Category
- Horlogerie