Manufacturer | Seiko Time Corp. |
Caliber Number | 8M26, 8M26A |
Movement Type | Quartz, battery-powered, multi-function |
Diameter | 24mm |
Casing Diameter | 25.5mm |
Height | 3mm |
Jewel Count | 4 |
Frequency | 32,768 Hz |
Accuracy Rating | Less than 15 seconds deviation per month |
Regulator? | Trimmer condenser |
Battery Cell | SR920W (371/370) |
Battery Life | 2.5 years |
Driving System | 2 piece step motor |
Coil Block Part # | 4002-042 |
Hand Count | 2 |
Functions | Central hours; central minutes; mode indicator at 6:00; alarm; chronograph/stopwatch; countdown timer |
Country of Manufacture | Made in Japan |
Known Models | Seiko Avenue (Ref: 8M26-7040, 8M26-600A) Seiko Quartz Chronograph (Ref: 8M26-7099, 8M26-8009, 8M26-7060) (Add your watch to the comments below…) |
The Seiko caliber 8M26 (8M26A) is a vintage multi-function quartz movement with an alarm and chronograph. This movement is a 2-hander with no seconds hand and no date.
This calibre was introduced in the late 1980s (circa 1988).
Some of the topics covered in this caliber listing:
Multi-Functional:
Notable features are that the hour and minute hands are controlled independently by two different motors, allowing for them to be used in various capacities beyond traditional time-telling.
The crown is used as a controller to select the mode, simply by rotating it forwards and backwards.
The mode indicator is at 6:00. The modes are listed below:
- TIME mode (Alarm disengaged) – Time display, alarm off
- TIME mode (Alarm engaged) – Time display, alarm on
- ALARM SETTING mode – Set the alarm time
- TIMER mode – Up to 60 minutes countdown timer
- Mode for adjusting the hand position – Set the time on the watch
- STOPWATCH mode – 60 minutes chronograph
Alarm Test:
To check if the alarm is working in your watch, there is an alarm test feature.
To test it, turn the crown until the mode is in TIME mode with the alarm activated. Press both the top and bottom buttons at the same time. The alarm sound should be audible while the buttons are pressed in together.
AC Circuit Reset:
The 8M26 is equipped with an electronic circuit reset switch. After a new battery is installed in the movement, you may have to perform a system reset aka short-circuit the movement to clear the information that was last stored in the integrated circuit. Do this will ensure that all functions work properly.
Additional Technical Information:
According to official technical documentation, the 8M26 is always consuming battery power, even when the hands are not moving. In Seiko’s own words:
“An extremely small amount of electricity is always supplied to the electronic circuit in order to make the watch start moving immediately and correctly after it is stopped and the battery itself discharges electricity.” -Source: Official Instruction Manual, Notes on the Battery
- Current consumption of the movement is less than 2.5 uA
- Current consumption of the circuit block is less than 1.6 uA
Additional Resources:
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