Omega Mégaquartz year 1970

For your information, I do not repair this type of watch.

The 1500 calibre (Megaquartz 2400)

If, in the field of wristwatches, the 30 mm calibre is the superlative calibre in mechanical technology, the 1500 is without question its equivalent in electronic technology. It is not only the world's first high-frequency quartz calibre (1970), but also the most accurate.
Developed in collaboration with the Battelle Institute in Geneva (whose contract with SSIH was signed in 1955 and taken over by Omega on 1 July 1969), and the result of 15 years of research, it ensures an unequalled precision of 1 second per month. This precision is about ten times greater than that of an ordinary quartz watch, and is due to the special design of a tiny lenticular quartz, in the shape of a disc, sealed in a capsule which oscillates at the almost unimaginable rate of 2,359,296 times a second. What is more, this high frequency enabled one of its versions, the calibre 1511, to be approved on 25 February 1974 by the Neuchâtel Astronomical and Chronometric Observatory as a... Marine chronometer. Until then, this had always been the prerogative of large timepieces. After 63 days of the most rigorous tests, it not only meets the standards set, but far exceeds them. The average rate deviation is only 2 thousandths of a second per day. What's more, since these official tests are only static, Omega supplements them with tests of resistance to shock, magnetism and humidity.

The reduction of its frequency to one step per second is achieved by means of two analogue dividers by 6, by transformers, which constitute the first watchmaking integrated circuit of the MOS, or Metal Oxide Semiconductor, type. In addition to its precision, its resonator also has other advantages over low-frequency models, such as better resistance to shocks and temperature variations.
In addition, the Megaquartz 2400 is the first watch to be equipped with the TSA (Timezone and Second Adjustment) device, which allows the time to be changed without disturbing the minute or second, to make fine corrections to the second and to synchronise it with the time signal.

For the first time in the history of watchmaking, this gives the second its full meaning.
To maintain the precision of an analogue quartz watch, the wearer must make the following three corrections:
1. the date, at the end of months of less than 31 days (mechanical corrector)
2. the time, when changing time zones or from summer to winter time and vice versa (mechanical corrector, with magnetic repositioning of the hand)
3. the second, to rectify small inaccuracies in the resonator or to block it until the time signal (electronic corrector).
With the TSA system, developed by Pierre-Luc Gagnebin, these interventions can be carried out in a few seconds.
The quartz is supplied by ITT. The integrated circuit is the result of a Faselec-Intersil-CEH cooperation. Designed by Peter Döme of Battelle, who patented it in 1968 under No. 583.929, the stepper motor (electrodynamic with inverted anchor, or percussion anchor) is manufactured by Omega, where it is developed by Willy Cleusix. Willy Cleusix is part of a working group led internally by John Othenin-Girard who, assisted by Bruno Erni, is also responsible for relations with Battelle for the development of the electronic module.

With its derivatives 1510/1515 (standard chronometers) and 1511/1516 (marine chronometers), the Megaquartz 2400 will be produced in about 10,000 pieces, of which some 7,000 for the calibre 1516 alone.
In 1975, the Marine Chronometer was awarded a gold medal and a diploma at the Leipzig Fair, attesting to its high scientific and technical level.
The particular shape of the calibre means that the 707 mm2 surface limit set by the Neuchâtel Observatory for wrist chronometers is not exceeded. This did not pose a problem as long as only standard chronometers were made with the 1510 (1972) and the 1515 (1973). But everything will change in 1974, as soon as the 1511 will get marine chronometer bulletins. Of these bulletins, there will be only two, in all. Because the Observatory immediately modified its regulations, so that only timepieces with a dial measuring at least 60 mm in diameter could be awarded this supreme title! Result: With its 24 mm dial, the Marine Chronometer is disqualified! Omega will have to have all its other timepieces approved by the Besançon Observatory!

One can ask oneself here what would have been the attitude of the persons in charge of the respectable Neuchâtel institution if the manufacturer of this insolent calibre had been one of the noble brands of the same cantonal origin (Girard-Perregaux, Movado, Ulysse Nardin, Zenith, for example) and not a commoner like Omega, and Bernese moreover...

Excerpt from the book Omega Saga, 1998

Author Marco Richon

ISBN 2-88380-010-3

The "Chronomètre de Marine" version will be launched in autumn (1974), at a price of 3,500 francs on the Swiss market.
Source: Revue, La Suisse Horlogère N° 14 of April 4, 1974

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