NOTICE: Read these instructions in whole. They will give you a good understanding of the operation of the Seiko Calibre NH34 (4R34) movement, and reduce any potential damage and failures in operational functionality.

Warning: Do not operate the date or the GMT quick set from the crown between the hours of 9pm and 3am as you risk rendering the date change mechanism useless. If you don’t know the time, don’t change the date. More on this to follow.

Manual Operation of the movement is controlled from the crown, some may call this a winder. The crown has three operating positions that control the different functions and complications of the Cal. NH34 (movement). Selecting the desired operating position is achieved by pulling the crown out gently. If you pull it too far, aiming to achieve the second position (date operation) you can simply push it back in and gently pull again.

Hand-winding – Calibre NH34 (movement)

The first operating position of the Calibre NH34 (movement) is the hand winding function.

The first position is where your crown is at rest. This can vary depending on your watch’s design, there are two options.

  1. You have a sports watch where the crown screws closed to create the water tight seal.
    The first positions is found by un
    screwing the crown until it is no longer engaged with the locking mechanism on the case.
  2. If your watch does not feature the screwed crown. The closed position (most pushed in) is the first operational position.

The first operational position is where you can hand-wind your watch. Essentially, this is putting power into the reserve. Approximately forty hand-winds of the crown in a clockwise rotation in this position will supply the reserve with a full supply. This will last approximately forty-one hours if unworn. If you intend to wear your watch everyday, your watch will require no further winding as your movement will supply power through the autowinding mechanism.

Date and GMT Quickset – Calibre NH34 (movement)

The second operating position of the Calibre NH34 (movement) controls the quickset of the day date and GMT complication.

Warning: Do not operate the date and GMT quick set from the crown between the hours of 9pm and 3am as you risk rendering the date mechanism useless. If you are unsure of the time your watch is displaying with regards to the 24-hour date function, skip to next, the third operational position, and follow instructions to change the time so you are sure to be outside this region of operation where your risk damage to your timepiece.

Date: Changing the date is done by turning the crown anti-clockwise. You will see the date wheel complete a part rotation and the next number will drop into view.

GMT: This movement has an additional hand (a fourth hand). This is a GMT hand and tracks the time in a second location. Changing the time of your desired second location is done by turning the crown clockwise. You will see the GMT hand complete a part rotation. Each click of the hand rotates the GMT hand one hour. This can be operated like so, until the desired second location time is selected. It will appear as half an hour on the dial as the GMT hand takes twenty-four hours to make one full rotation of the dial. The hour hand makes two full rotations in a twenty-four hour period.

Setting the Time and Hacking – Calibre NH34 (movement)

The third operating position of the Cal. NH34 (movement) allows the user to set the time and affect the second hand hacking (stopping) function.

The third and final operating position can be reached by pulling the crown out to the final position. You will notice when are in this position, as the second hand will stop moving. This is the hacking feature of your Cal. NH34. The crown rotated in a clockwise position will move the hour and minute hands in a clockwise rotation. You should set the time by using the clockwise rotation for the bulk of the movement. It is understandable that you may miss the time that you wish to set your watch to. In this case, micro adjustments to the time in an anti-clockwise rotation are fine, but if you move over a few hours past, it is recommended that you continue the clockwise rotation until you achieve a full rotation.

DON’T: Turn your crown anti-clockwise in the hope that the date will go backwards. It will not. You will not be happy with the results!

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