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Seiko 7T27 Movement Or Circuit Board?


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Evening chaps.

 

I have a Seiko 7T27-7A20 on the bench at the moment with a damaged circuit board. The rest of the movement id fine.

Do I have any other options other than the Epson YM57A movements for sale on eBay? 

 

Cheers.

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2 minutes ago, jaycey said:

Evening chaps.

 

I have a Seiko 7T27-7A20 on the bench at the moment with a damaged circuit board. The rest of the movement id fine.

Do I have any other options other than the Epson YM57A movements for sale on eBay? 

 

Cheers.

What is the damage to the circuit board? A few close up pictures might help.

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I'll get some photos but so far I know the tab that extends into the battery compartment is snapped off and the contact where the start/stop lever contact the board is missing.

There's also some damage near where the hacking lever makes contact.

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7 minutes ago, ro63rto said:

Underneath it's the same isn't it?
I would just switch top plates if you want it to still say 7t27

 

And change the white date wheel on the Epson for the black original.

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Swap the circuit if you can first, because the height of the hour wheel / canon pinion / CS pinion vary between models. Certainly the one fitted to the Seiko Gen 2 Military chronograph differs to the newest movement available. Can measure the current draw later to see if it’s running well enough to give a thumbs-up. 

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Got the new movement today and the good news was, it is a direct swap, just had to swap the datewheels as the new movement had a white datewheel and the Seiko Gen 2 has a black one. Simple enough to do. Swapped the 7T27 battery plate over with the original Seiko markings too:)

All back together and working great!

IMG-1169.jpg

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  • 1 year later...

Hello 

I am looking for a replacement for the 7T27 but can’t find the YM57A anywhere for sale. Would love to get my Gen 2 up and running again. Does anyone know of a another replacement for it??

 

many thanks 

 

seb

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