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(1970's) 7750 chrono-automatic movements used by omega

  1. maximilian g Feb 12, 2016

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    I seek knowladge please this is more about the developement and different types of the early movements rather than the watch cases

    I am trying to learn about the 1970's chrono-automatic incabloc movements used by omega. preferably 7750 varients if any?
    please add to this thread any information about the different movements used and also the different dials used.

    Lemania ( omega cal 1050 )

    Omega Regatta , with the Lemania 1345 movement as probably very few were sold. The left picture below was taken at the Omega museum. Like the Heuer version, Omega counts the seconds up from zero to 60, instead of down from 60 to zero as the Aquastar, Tissot and Lemania models do. The caseback is unbranded, and the rotor is signed ‘Lemania’.
    [​IMG]

    Model: Omega Seamaster Yachting.
    • Reference: ST 176.0010.
    • Caliber: automatic Lemania 1341 movement (Omega 1040).
    • Case size: barrel shape 43 x 43 mm.
    • Year: 1973/1974.
     
    Edited Feb 14, 2016
  2. Archer Omega Qualified Watchmaker Feb 12, 2016

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    "I am trying to learn about the 1970's 7750 chrono-automatic incabloc movements used by omega."

    You do realize that the 1040 (1341) is NOT a 7750 derivative, right?
     
  3. Andy K Dreaming about winning an OFfie one day. Feb 12, 2016

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    Both watches you reference are derived from the Lemania 1340. Here's my 176.0010:
    [​IMG]

    As far as I know Omega never used the 7750 until well after Valjoux was folded into the Swatch Group when it became the basis of the Speedmaster Date watches (late 1990s, maybe early 2000s).
     
  4. maximilian g Feb 12, 2016

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    yes, thanks Archer, I do understand that 1040 is not from the 7750 .I am seeking knowladge about any 1970's developement / collaborations by omega with chrono-automatic movements before the change in fortunes.
    On my part this is a leading question as I have come accross a possible prototype that has sparked my interest with this.
    I am interested if there was a possible connection in the 1970's if lemania were involved with omega at the time with possible chronograph automatique prototypes?

    Also if the same was the case with Valjoux?

    i have read this basic info:

    Valjoux 7750
    Introduced on July 1, 1974, at the height of the quartz crisis, the 7750 was released five years after the race to build an automatic chronograph was won by Zenith's El Primero and the Chronomatic consortium. It sold well initially (estimated at 100,000 pieces in 1974) but was doomed the very next year. Production stopped in 1975 but demand was so low that supplies lasted into the 1980's. Local management retained the dies and equipment, allowing them to restart production in 1985 as demand for automatic watches rebounded.
    Thanks to a durable and inexpensive design and strong support from Swatch Group, the 7750 has become the most common Swiss automatic chronograph movement. Since the takeover of Valjoux by ETA the movement is also called ETA 7750.

    The 7750 is a self-winding chronograph movement with 25 jewels, ball-bearing rotor, unidirectional winding, 1/8-seconds counter, 30-minutes counter, 12-hours counter, 28.800 A/h, power reserve ca. 44 hours.

    The key distinguishing features of the 7750 family are as follows:

    • Conventional integrated center-mounted automatic winding in one direction (unlike the barrel-wound Chronomatic)
    • Cam-controlled chronograph functions using a "heart piece" (unlike the more complex column or pillar wheel style)
    • Simple three-plate brass base (rather than complex bridges)
      • Calendar plate with modular components
      • Main plate with off-center center wheel, hacking lever, and simple bent-spring ratchet
      • Top plate with additional winding bridge
    • Etachron regulator and balance spring stud
    The initial 7750 movement used 17 jewels, but current versions of the 7750 have 24 or 25. It has been supplied at both 21,600 or 28,800 beats per hour, though the latter is much more common.

    ETA produces 7750 movements in three finishes:

    1. Elaboré
    2. Top
    3. Chronomètre

    I am trying to find out if:
    omega were looking at a valjoux 7750 chrono-automatique incabloc in the 70's to put into a seamaster ?

    The watch I have come accross ( photos further down in this thread) in the end became the "seamaster yachting" which finished up as a seamaster with a Lemania 1341 = Omega 1040 movement.
    Watch reference : ST 176.0007

    I was hoping to see what members know about chronograph movement developement in the 1970's, and whether the info i have is wrong?
     
    Edited Feb 14, 2016
  5. Ravineman Feb 12, 2016

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    I think you're the expert on this one, lol
     
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  6. maximilian g Feb 12, 2016

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    I was hoping members like archer who have been very helpfull in the past would be able to shed light on this?( he has been helpfull in the past to me and other members with their threads)

    I just havent seen any threads on early chronograph types in the 1970s
     
    Edited Feb 14, 2016
  7. Archer Omega Qualified Watchmaker Feb 12, 2016

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    You are all good up to this point - all the 7750 stuff that is on Wikipedia and blogs is generally accurate as far as I know, but starting below is where I would have trouble verifying anything for you. Who told you all this?

     
  8. Mouse_at_Large still immune to Speedmaster attraction Feb 12, 2016

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    Not wishing to derail this thread, but that could explain the difference between the two very similar Polaris models i.e. the TB 378.0885 and the TR 378.0885 as listed on the Omega Database. Despite both being listed with the calibre 1154, the slightly earlier model is listed with 17 jewels, the later with 25.
     
  9. maximilian g Feb 12, 2016

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    This started out when I saw a watch case which in effect was a stainless steel
    OMEGA Automatic Seamaster ,cal 1040 self-winding mechanical. Chronograph but was engraved with :
    swiss made 7750 Chrono-Automatic incabloc waterresistant all stainless steel then with a model number in the middle.
    the inside of the case back is stamped with :
    omega watch Co ( in a triangle with logo) fab.suisse swiss made

    [​IMG]
    • watch body which measures 40mm by 43mm and has 22mm lugs
    • 36mm water tight case back
    • 35.5mm Crystal
    • Omega Yachting Bezel
      [​IMG]

      [​IMG]
     
    Edited Feb 14, 2016
  10. maximilian g Feb 12, 2016

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    I am wondering if this could have been a possible early prototype?

    i was informed by the owner that:
    the Omega 7750 Chrono-Automatic 280 GX watch body that is PVD coated in diamond like carbon. These PVD cases were made by Omega and never put into mainstream production and were sold in auction in Sweden in the 1970's.

    help would be appreciated if any members have any knowladge of this type of developement or have come accross any of these watches in other forms?
     
    Edited Feb 14, 2016
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  11. Archer Omega Qualified Watchmaker Feb 12, 2016

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    In terms of the cases, the TB model it titanium and yellow gold, and the TR model is titanium and pink gold.

    Certainly the 7750 came in a 17 jewel version, and I think the change to 25 jewels was made in about 2000 or so. Just going from memory I don't think I've ever seen an Omega movement based on the 7750 that only had 17 jewels. In fact it's actually pretty rare to see any 7750 with only 17 jewels. I think the last one that crossed my bench was in a Tag of some sort...

    Cheers, Al
     
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  12. Mouse_at_Large still immune to Speedmaster attraction Feb 12, 2016

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    @Archer - thanks for taking the time to reply. Looking at the Omega Database, I find it hard to distinguish the pink/yellow gold difference. In fact I own the TR version and it's definitely yellow :)

    Unless the Omega Extranet is giving different information, I think the dial is the main difference between the models e.g. subdial number orientation, "tachymeter", lume plot sizes etc. plus the later bracelet does not have gold (plated?) centre links (and possibly an uprated 1154 movement).

    This may also be of interest http://www.chronocentric.com/forums/omega/index.cgi?md=read;id=3100
     
    Edited Feb 12, 2016
  13. Andy K Dreaming about winning an OFfie one day. Feb 12, 2016

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    That set was on EbayPurchases made through these links may earn this site a commission from the eBay Partner Network in December. I was curious too, but I think the seller's "baggie" was someone's never-completed franken project. My best guesses:
    -Mid-Case could be a custom-PVD case to a 176.007 or similar
    -crystal/bezel could be from a 176.0010 or a Tissot Navigator
    -Caseback =?? Who knows. I'm leaning fake.

    Omega never branded it "7750", it was always modified and relabeled as an Omega calibre. Even so, the outside of the caseback is not marked in anyway similar to how Omega did in the past. And Omega using a Valjoux 7750, even in a prototype, makes no sense at all for the 1970s, as Valjoux and Lemania were rivals at this time.
     
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  14. Archer Omega Qualified Watchmaker Feb 12, 2016

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    055TB3780885 - TIT. JEL.GOLDCASE CAL.1154

    055TR3780885 - TIT.PINK GOLD CASE CA.1154 120M

    Two things:

    1 - pink gold is not necessarily permanently pink, and it will "fade" in time and look more yellow.

    2 - case backs can be swapped.

    Okay a third thing - R and B could look very similar with a quick look...are you sure yours is a TR?

    Cheers, Al
     
  15. maximilian g Feb 12, 2016

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    It was on ebay Andy K
    it has an Omega yachting bezel and crystal
    the case back and coating are interesting as its not directly copying a spacific model could it be a prototype?
     
    Edited Feb 14, 2016
  16. Mouse_at_Large still immune to Speedmaster attraction Feb 12, 2016

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    Edited Feb 12, 2016
  17. Archer Omega Qualified Watchmaker Feb 12, 2016

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    Yes, I wasn't doubting that it looked like yellow gold - it has the dial for the yellow gold model as well. Do you have a shot of the inside of the case back? TR is absolutely the designation for the pink gold version...
     
  18. Mouse_at_Large still immune to Speedmaster attraction Feb 12, 2016

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    I believe it has the correct dial for the TR version as well :D, in fact it looks exactly like the one on the Omega Database. The only oddity seems to be the details you have (from the Extranet?) which seem to indicate it should be rose gold. As for the caseback and/or movement, that will have to wait until it goes off for a service - sorry.

    I really don't want to further derail this thread over my particular obsession, but I do appreciate you taking the time to discuss.
     
  19. Archer Omega Qualified Watchmaker Feb 12, 2016

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    Can I ask why you believe it is TR when all evidence points to it being a TB?

    We both agree it's yellow gold and titanium. The only thing we don't agree on is that TR is the yellow gold version. Omega says the TB version is yellow gold...that case is still available for purchase if you have a spare $7k laying around. They show a picture of the TB case on the Extranet...it is clearly yellow gold.

    TR is the pink gold version. Omega says this...okay I'm done beating my head against the wall...
     
  20. Andy K Dreaming about winning an OFfie one day. Feb 12, 2016

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    Not a 1970s 7750. Per A Journey Through Time the earliest Omega use of cal. 7750 based caliber was 1150 in 1990, which was initially offered in 17J. image.jpeg
     
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