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Police 12740 Chronograph

tkdwarrior

By tkdwarrior
in Watch Repairs Help & Advice

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tkdwarrior New Member

tkdwarrior

Posted
Posted

Greetings everyone, I was able to acquire a second hand police chronograph watch which has miyota chronograph quartz movement.

d541ea22bb3b918211e8a0c0c0b1e306.jpg

The problem is the minute dial the one on the left does not reset when I reset the chronograph abd when trying to calibrate it, I cannot calibrate the hand of that dial to go back 60 minute mark. My watch maker has done all he could to fix the problem, though the minute dial moves when I operate the chronograph it does not reset back to 60 minutes nor can I calibrate it to do so. Any ideas how to fix this problem? Thanks for your responses in advance:)

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bobm12 Distinguished Member

bobm12

Posted
Posted

Hi tdkwarrior, it looks like a Miyota OS10 or 0510 for some suppliers (or some of its versions: 11, 60, etc).

 

In any case, regardless, pull the crown all the way out and press and hold the lower pusher. It will start spinning the lower/seconds eye and the left/minutes eye will be moving along, marking the minutes until it approaches the mark you want. Be careful because it is the lower eye the one that "sets" the left eye with its revolutions. If you overshoot your mark, you have to do it over again. The top pusher sets the right eye or the big seconds depending on the miyota movement so that one is not problem. once everything is the way you like, you can push the crown back in and all will be well.

 

Hope it works/helps

 

Cheers,

 

Bob

 

PS. Welcome aboard.

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