The Seiko 9723A is a vintage quartz analog movement that combines classic styling with practical functionality. Introduced in the late 1970s and widely used through the 1980s, the 9723A was part of Seiko’s highly regarded 9700-series—known for its reliability, compact dimensions, and high-accuracy quartz timekeeping. This movement features a three-hand layout with both day and date complications, making it a versatile choice for daily wear.

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Technical Specifications

• Caliber Number: 9723A

• Movement Type: Quartz (step motor, analog)

• Display: Hour, Minute, Central Seconds, Day-Date

• Calendar:

  • Day: Bilingual in many models (e.g., English/Spanish or English/French)

  • Date: Numeric

• Jewels: 2 jewels

• Battery Type: SR920SW (1.55V silver oxide)

• Battery Life: Approximately 3 years

• Accuracy: ±15 seconds per month

• Dimensions:

  • Diameter: ~26.0 mm

  • Height: ~3.2 mm

• Hand Fitting Sizes:

  • Hour: 1.20 mm

  • Minute: 0.70 mm

  • Seconds: 0.20 mm

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Functions and Crown Operation

The 9723A movement features a classic three-position crown:

• Position 0 (pushed in) – Normal operation

• Position 1 (first click) – Quickset calendar

  • Turn clockwise to set the date

  • Turn counter-clockwise to set the day

• Position 2 (fully pulled out) – Time setting with hacking (the seconds hand stops)

This quickset functionality allows for rapid adjustment of both calendar features without needing to cycle through 24-hour periods.

Note: Avoid changing the day or date between 9 PM and 4 AM to prevent damage to the calendar gear train.

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Battery Replacement and Reset Instructions

To replace the battery and perform a reset:

1. Open the case back using the proper tool

2. Remove the depleted SR920SW battery using plastic tweezers

3. Install the new battery carefully, ensuring proper polarity

4. Locate the AC (All Clear) contact—usually labeled near the battery terminal

5. Using metal tweezers, short the AC contact to the negative terminal (case or spring) for 2–3 seconds

6. Confirm that the second hand starts ticking normally

This reset reinitializes the integrated circuit and is necessary after every battery change.

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Servicing Notes

• The 9723A is designed to be low-maintenance

• Lubrication is limited to key gear train pivots and date-change components

• Clean the calendar components gently to prevent sticking or jamming

• The step motor and coil are fragile—handle with care during disassembly

• If the movement fails due to a damaged IC or coil, full replacement is typically more economical

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Identification and Watch Models

The movement is marked “9723A” on the main plate. You’ll find this caliber in a variety of Seiko dress and casual watches from the late 70s and 80s. These models usually feature metal bracelets, domed mineral crystals, and classic dials with the day-date window at 3 o’clock.

Common Seiko reference numbers associated with the 9723A include 9723-xxxx, particularly in the Seiko Quartz and Seiko SQ series.

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Conclusion

The Seiko 9723A is a classic quartz movement that blends durability, accuracy, and functionality. With its slim profile, quickset bilingual calendar, and time-hacking feature, it remains a highly respected movement among vintage Seiko collectors and watchmakers. When properly maintained, the 9723A continues to deliver reliable performance decades after its original release.

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