[kristo]

Hey folks,
I recently came across this Seiko 7a28. I always thought these were only produced in the 80's, but using the Seiko watch production date calculator, I learned that it was produced in October 1992. Do you think this is accurate?
Thanks for reading,
Chris.

 

[Dazzler]

.... but using the Seiko watch production date calculator, I learned that it was produced in October 1992. Do you think this is accurate?

No. Because it was very likely produced in October 1982.

 

[kristo]

That passed through my mind too. I thought they were produced only from '83 to '89 though. So obviously I found an early one.
Thanks!

 

[Dazzler]

An old thread from the old SCWF

http://www.network54.com/Forum/78440/thread/1238452999

While the "official" release of the 7A series watches was early 1983, production seems to have commenced in late 1982. Though it is unusual to see one with a 2Nxxxx serial number, I have seen many with a 2Dxxxx serial number. I think Seiko does this so supply will match demand upon release of the watch. They did the same thing with the 6R15 when they released it...the official release was in November, but these watches had serial numbers indicating they had been produced a month or two prior.

 

[kristo]

http://www.network54.com/Forum/78440/thread/1238452999

Very interesting. Thanks. But why wouldn't the calculator (http://www.csce.uark.edu/~jgauch/photos/seiko/) indicate that year? Presuming it is programmed to use only the earliest release date because earliest production date is not determined?

Cheers Christoph

 

[Dazzler]

There's definitely something wrong there. I tried keying your watch's serial number into John Gauch's calculator (using both 2Oxxxx and 20xxxx - which I know is wrong) and got the same incorrect answer - October 1992. Whereas clearly it should be October 1982.

Yours is probably one of the earliest 7A28's produced (per Aaron's and Hung's posts in that old SCWF thread).
The last Seiko branded 7Axx's produced were the 7A38-7075; 7A38-7085 and 7A38-7295 manufactured (or should I more correctly say 'assembled') by Seiko's Brazilian offshore ZFM operation in Manaus - in September 1989. These have 99xxxx serial numbers.

Other Seiko owned subsidiaries and OEM's - notably Orient, Yema and Ateliers ABC (Cartier Ferrari Formula) continued using re-branded 7Axx movements into the mid 90's.
By late 1989, Seiko themselves had 'moved on', dropping the 7Axx in favour of the (cheaper to produce) 7Txx.

 

[kristo]

Thanks for this little history of the 7A!

Now I remember the man who did the estate sale wrote this watch was from the 70's. I knew this was not possible but it also indicates a production date earlier than 1992.