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Chronomaster: 4 1/2 sec band over 5 years with new movement; what do I do now that batty is dead?

1767 Views 13 Replies 7 Participants Last post by  Hans Moleman
I bought my Citizen Chronomaster through Katsu Higuchi in Japan in 2007. Subsequently I posted much data here at Watchseek showing how the watch rapidly sped up over time and way out of spec, repeating that bad behavior after going back to Japan for service. Finally Higuchi decided it needed a new movement and in fact after that it performed MUCH better. I'm enclosing a graph showing that in the ~5 years it ran on its latest battery the watch stayed within a 4 1/2 second band compared to UTC, although that would not have been true for much longer.

But now the battery is dead and the watch is out of warranty. Higuchi did not reply to my last request for information about how to get the battery replaced and the watch regulated.

I have two questions for you better-informed people.

1) How can I get the job done by Citizen, presumably in Japan?

2) I can replace the battery myself, and grease the o-ring. I can certainly NOT regulate the rate, and beyond that I'm worried that the rate and TC parameters might be stored in volatile memory and would be lost if the battery is changed. Does anyone have experience changing the A660 battery at home?

Any help will be greatly appreciated!
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I can't help with advice on Chronomaster battery replacement.

I can help with an explanation for the disappearance of the 2 seconds.
They were caused by a failure to move the seconds hand. Once the rotor failed to move the first time, it was in the wrong position for the subsequent stepper pulse. The subsequent pulse failed to move it as well. Two seconds were lost.

The stepper motor needs a positive pulse to move the rotor to the North. And a negative pulse to move it South. And for that to work, the rotor needs to be in the proper position so that it can move North or South.

The new VHP's have this thing to pick up on those hick-ups and correct for them at a later stage.

Glad to see that your insistence on proper regulation has payed off. Eventually.
If you're doing it yourself, I've got one tip.

The last battery change, I made sure to properly grease the o-ring. That made all the difference.
Closing it was that much easier since you don't have to work against the friction.
And you're sure the rubber sits properly all the way round.

Lubricant meant for o-rings obviously.

You'll be surprised why you bothered with sending it to Japan in the first place.

Still love your inventive rate measuring technique.
Another thing learned.
Well done Sir!

You see those Breitling ads for their service. Clearly meant to intimidate.
No, you don't need an operating theater to change a battery. That is, unless you decide to swallow the battery.
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