Seiko Cal. 8V20A Parts Catalogue Technical Guide
Complete parts catalogue and technical service guide for the Seiko Cal. 8V20A quartz chronograph movement. This workshop manual covers repair, maintenance, and parts identification: full technical specifications, detailed movement diagrams (Ø29.1mm, height 3.3mm including battery), step-by-step disassembly and reassembly procedures with numbered component identification, and comprehensive parts listing. The movement features 3 hands with multi-function hand, step motor with fixed-width pulse system, 24-hour alarm, countdown timer (up to 30 minutes), stopwatch with 1/10 second increments (up to 30 minutes), hands zero-reset adjustment, and alarm test function. Specifications include trimmer condenser regulation, 0 jewels, monthly rate better than 20 seconds, and compatibility with SR1130W batteries (Seiko, Maxell, Sony) or Eveready 389—approximately 2 years service life at 1.55V. Essential reference for watchmakers and technicians performing preventive maintenance or troubleshooting on this reliable quartz chronograph caliber.
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Document Details
- Format
- Pages
- 5
- Size
- 139.2 KB
- Category
- Watchmaking