# Thermocompensated Omega Seamaster



## vizi (Oct 24, 2007)

Hi everyone, this is my first post in this forum and it is about my Omega Seamaster.
Are you aware that Omega has used the ETA 255.561 (Omega caliber 1441) movement in its titanium Seamaster in the late 1980s? 
Link: http://www.isozaki-tokei.com/syuri-omega2.htm
This is the same dual-oscillator thermocompensated movement that was first introduced in the Longines Conquest VHP in 1984.

I own a stainless steel version of the Seamaster Professional 200m quartz (Omega caliber 1438 = ETA 255.461) and I also have a damaged Longines Conquest VHP (dial and hands are seriously damaged) with working electronic module. So I replaced the electronic module of my Seamaster with the electronic module (including the dual-oscillator) of the damaged VHP. So I ended up with a thermocompensated Omega Seamaster! 
I'm going to follow the calibration instruction to fine-tune the movement.
I'll keep the forum updated about the result of the calibration.


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## Eeeb (Jul 12, 2007)

The use by Omega of the dual xtal movement was news to me! Swapping around ETA quartz movements of the same size is not difficult... and often represents a much easier solution than massive repairs.

Good luck on the calibration!! (If you want to sell some links off the Longines, please send me a PM... mine's way too small and Longines is no help anymore on bracelets that are not in production -- one of the differences between Longines and Omega.)


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## ppaulusz (Feb 11, 2006)

Eeeb said:


> The use by Omega of the dual xtal movement was news to me!...


Me too! Just in case that there is no misunderstanding, the Omega Seamaster (Cal.1441) operation manual confirms it (see attachment from the net) and it also mentions that the quartz thermometer (the second oscillator) has a frequency of around 262kHz (the first time I saw that detail in an official booklet)!


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## Eeeb (Jul 12, 2007)

Very interesting! I think this is the first time we have a frequency for the second oscillator... good find!


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## vizi (Oct 24, 2007)

The pictures


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## Fatpants (Sep 6, 2007)

Great work, how's the accuracy?

Fats:-!


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## ppaulusz (Feb 11, 2006)

Fatpants said:


> Great work, how's the accuracy?
> 
> Fats:-!


Looks like (according to the thread opener) he just done the calibration so it might take a while to see the result of it.
I look forward to it as well!


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## Bruce Reding (May 5, 2005)

Welcome vizi! Sounds like some good handyman work there. :-!

I assume that you're aware of this thread:

https://www.watchuseek.com/showthread.php?t=86346

We'll be very interested to hear how the regulation goes!


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## vizi (Oct 24, 2007)

Bruce Reding said:


> Welcome vizi! Sounds like some good handyman work there. :-!
> 
> I assume that you're aware of this thread:
> 
> ...


of course i tell you how accurate but i need some time to check it out,but you'll be informed at this topic.


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## Ras44 (Sep 13, 2007)

I am very interested in your post, since I also have a SMP 200. What strikes me is that you have stated that your SMP 200 used the Omega Caliber 1438, but when I e-mailed Omega with the SMP's serial number number they told me that it used the Caliber 1538. Can you provide the reference number for checking? Mine is a 2850.50.02.



vizi said:


> Hi everyone, this is my first post in this forum and it is about my Omega Seamaster.
> Are you aware that Omega has used the ETA 255.651 (Omega caliber 1441) movement in its titanium Seamaster in the late 1980s?
> Link: http://www.isozaki-tokei.com/syuri-omega2.htm
> This is the same dual-oscillator thermocompensated movement that was first introduced in the Longines Conquest VHP in 1984.
> ...


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## vizi (Oct 24, 2007)

Ras44 said:


> I am very interested in your post, since I also have a SMP 200. What strikes me is that you have stated that your SMP 200 used the Omega Caliber 1438, but when I e-mailed Omega with the SMP's serial number number they told me that it used the Caliber 1538. Can you provide the reference number for checking? Mine is a 2850.50.02.


Ras44
Sorry,but i cant check the reference number,the watch is made in 1991 and not me is the first owner
As you see on the pictures,the mechanical part at the two movement is the same,ETA 255.461
The electro module is the different,this is becouse Omega is give that another caliber number.
As far as i know the Omega 1438 caliber appears in 200m SMP.
The Omega 1538 caliber is in the 300M SMP. (James Bond Omega).
No one of them is thermocompensated movement.
The thermocompensated movement: Omega 1441

I put some link to the topic:

http://mr-coo.com/battery/brand/seamaster-1438.html

http://chronocentric.com/forums/omega/index.cgi?noframes;read=2495

http://home.xnet.com/~cmaddox/omega/tables/seamaster/combined.html#Electronic_Divers

http://mr-coo.com/battery/brand/seamaster1441.html


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## Ras44 (Sep 13, 2007)

Thanks a lot for the detailed answer. Well, like you, I thought my watch had the 1438, but it appears that, maybe, just maybe, 1992 models got the 1538, and it seems like mine is a 1992 model. I say that because I asked Omega and they wouldn't tell me the production year of my watch. Other than that, which I understand, they were very courteous with me. If you would like the reference number for your watch, just e-mail them ( [email protected] ) with the serial number of your watch and they will provide the reference number. Here is a copy/paste of the communication:

Dear Mr ------,

We thank you for your e-mail and wish to congratulate for having purchased an Omega watch.

The serial number you provided us with corresponds to the following model:

·*Reference 2850.50.02*
·*Model Seamaster 200M Gents watch*
·*Calibre 1538 Quartz*

We hope that the above information is satisfactory and wish you much pleasure with your new OMEGA watch.

With kind regards,

Maria Mastrodonato
INTERNATIONAL CUSTOMER CARE
Ω OMEGA SA
RUE STAEMPFLI 96
2500 BIENNE 4
SWITZERLAND
[email protected]
www.omegawatches.com



vizi said:


> Ras44
> Sorry,but i cant check the reference number,the watch is made in 1991 and not me is the first owner
> As you see on the pictures,the mechanical part at the two movement is the same,ETA 255.461
> The electro module is the different,this is becouse Omega is give that another caliber number.
> ...


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## vizi (Oct 24, 2007)

The production year of watch:
I put some link to the topic:http://home.xnet.com/~cmaddox/omega_serial_numbers.html


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## Ras44 (Sep 13, 2007)

Thanks a lot for the information! The serial number matches with the 1991 model year, but of course the guide tells that it could be off about 1 or 2 years. Well, the mystery won't be over till I open the watch, and I think there's about a year of battery life left on my watch. Still, thanks a lot for the great information and congratulations on your thermocompensated SMP 200! The SMP 200 is pretty rare itself among the Seamaster Professional series, a thermocompensated one is a gem!



vizi said:


> The production year of watch:
> I put some link to the topic:http://home.xnet.com/~cmaddox/omega_serial_numbers.html


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## vizi (Oct 24, 2007)

Fatpants said:


> Great work, how's the accuracy?
> 
> Fats:-!


Hi all,now after the 5th week use,i tell you how the calibration worked.
To a radio controlled clock there is no difference neither + or - way.I'm curious how the Omega Seamaster 1441 movement works for a year.sorry for my english:-(


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## Eeeb (Jul 12, 2007)

Good job! and good luck! (... and your English is OK too.)


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## ppaulusz (Feb 11, 2006)

vizi said:


> Hi all,now after the 5th week use,i tell you how the calibration worked.
> To a radio controlled clock there is no difference neither + or - way...


Congratulations, excellent result!:-!


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## vizi (Oct 24, 2007)

Eeeb said:


> Good job! and good luck! (... and your English is OK too.)


Thanks


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## vizi (Oct 24, 2007)

ppaulusz said:


> Congratulations, excellent result!:-!


Thanx ppaulusz,but i cant make it without you,thanks for your help.


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## Bruce Reding (May 5, 2005)

vizi said:


> To a radio controlled clock there is no difference neither + or - way.


Excellent! :-!


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## webvan (Dec 11, 2008)

vizi said:


> Hi everyone, this is my first post in this forum and it is about my Omega Seamaster.
> Are you aware that Omega has used the ETA 255.561 (Omega caliber 1441) movement in its titanium Seamaster in the late 1980s?
> Link: http://www.isozaki-tokei.com/syuri-omega2.htm
> This is the same dual-oscillator thermocompensated movement that was first introduced in the Longines Conquest VHP in 1984.


It seems the 1441 was also used in the non titanium Seamaster as well, the one that looks like this :










At least if the listing of some past eBay auctions is to be believed ! Trying to track down a topic that lists all the Omega watches with the 1441...


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## T. Wong (Apr 5, 2006)

Great thread! I own that non ti model, Seamaster quartz two toned, found here in Japan in 2003. From the Japanese link, this model states cal. 1438. So I'm curious if it is indeed a 1438 or 1441...


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## Eeeb (Jul 12, 2007)

This watch was made with both calibres... the 1441 seems to be less common.


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## webvan (Dec 11, 2008)

Eeeb said:


> This watch was made with both calibres... the 1441 seems to be less common.


Had this been discussed before, I never saw any mention of the 1441 being used in another watch than the Seamaster Pro 200M. Actually I started a new topic about the 1441 and the watches it was used in ;-)


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## T. Wong (Apr 5, 2006)

webvan said:


> Had this been discussed before, I never saw any mention of the 1441 being used in another watch than the Seamaster Pro 200M. Actually I started a new topic about the 1441 and the watches it was used in ;-)


Thanks for the feedback!


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## webvan (Dec 11, 2008)

Just got the "hybrid", 1441 swapped to 1445 during repair !

Nice design, albeit a bit small with its 32mm exluding the crown. Hard to adjust it to my 7.1" wrist too...either a tad too tight or too loose! Already had thay problem with other Genta designs, wonder if there are half links available ?

Started a worn accuracy test run...


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## T. Wong (Apr 5, 2006)

webvan said:


> Just got the "hybrid", 1441 swapped to 1445 during repair !
> 
> Nice design, albeit a bit small with its 32mm exluding the crown. Hard to adjust it to my 7.1" wrist too...either a tad too tight or too loose! Already had thay problem with other Genta designs, wonder if there are half links available ?
> 
> Started a worn accuracy test run...


Yes, same here....a bit too tight now since I had bought mine....and the other Seamaster pre-Bonds are about a link too short.....
Was contemplating bidding on a basic model just for the links! but all the pre-Bonds and Polaris models are selling over $380USD.....
One post is selling one link for 6900yen! or over $75usd...ugh.....

When wear my grey dial basic model, I just think of the watch more as a wrist fashion item jelwelry, no so much as a timepiece...haha!


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## webvan (Dec 11, 2008)

Wow that's expensive ? For a simple SS link or a gold+ss link?

Have you looked on Ofrei's site? I was planning to do that to see if there was a thing as half-links...let's see : reference is 1455/448...here we go : http://www.ofrei.com/page662.html - $25, seems reasonable enough ! No full links though it seems http://www.ofrei.com/page1278.html


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## T. Wong (Apr 5, 2006)

webvan said:


> Wow that's expensive ? For a simple SS link or a gold+ss link?
> 
> Have you look on Ofrei's site? I was planning to do that to see if there was a thing as half-links...let's see : reference is 1455/448...here we go : http://www.ofrei.com/page662.html - $25, seems reasonable enough ! No full links though it seems http://www.ofrei.com/page1278.html


6900yen for one SS link!....thanks for the Ofrei find!


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## webvan (Dec 11, 2008)

Wouldn't that be 2200 yen ?

I'll be getting a half-link from them, wonder why they don't have full links but maybe they can special order them.


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## T. Wong (Apr 5, 2006)

webvan said:


> Wouldn't that be 2200 yen ?
> 
> I'll be getting a half-link from them, wonder why they don't have full links but maybe they can special order them.


Nope, if the seller had listed that price,I'd have bid on it! haha! Remember, here in Japan, prices are often higher than in the West! There is no Ofrei type parts company I know of in Japan. Consequently I often have my vintage watches serviced in the USA, UK etc. by fellas who know where to source parts (ie. in the UK is Cousins...).


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## T. Wong (Apr 5, 2006)

webvan said:


> Wouldn't that be 2200 yen ?
> 
> I'll be getting a half-link from them, wonder why they don't have full links but maybe they can special order them.


Webvan, here is that post, one link for 6900yen again...on Yahoo Japan auction..
http://page4.auctions.yahoo.co.jp/jp/auction/d108122321


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## webvan (Dec 11, 2008)

Ok, Japanese is not my forte, good thing I only need a half link and that Ofrei has it ;-)


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