Ronda 4120.B Technical Data - Specification and Assembly

Technical data sheet and assembly manual for the Ronda 4120.B quartz watch movement, a 12½-ligne caliber engineered for precision timekeeping. The documentation provides complete specifications essential for watchmakers and technicians, including dimensional tolerances (Ø 28.60mm, height 4.40mm, case fitting 28.00mm), movement profile, and battery configuration using a 395 cell with rated autonomy of 48 months. Stem specifications are detailed, covering thread pitch (0.90mm) and positioning height (1.90mm). The assembly section contains step-by-step instructions with clearly labeled configuration diagrams (A, B, C) and itemized components—main plate, cannon pinion with driver, hour wheel, centre bridge, sliding pinion, handsetting stem, setting lever, yoke, pusher jumper, stators, rotor, intermediate wheel, and second wheel—enabling proper construction and alignment. Performance data covers operating torque ranges, chronometric accuracy parameters, functional temperature limits (0°C–50°C), magnetic field immunity, and shock resistance certification to NIHS 91-10 standard. Includes functional crown positions for time-setting and calendar operations. Essential reference for service technicians, repair professionals, and watchmakers working with this caliber.