A wristwatch with a quartz electronic calibre

At the beginning of 1969, no official mention was made of the potential production of wristwatches fitted with a quartz electronic movement. However, a secret project had been initiated within the walls of the manufacture. Known as the "projet sablier" or “hourglass project”, its aim was to develop and produce a quartz Longines watch before 1970.

Nonetheless, Longines was associated, together with other watchmaking companies and other firms, with the work carried out by the Centre Electronique Horloger (CEH), which was studying the design of a calibre using the piezoelectric properties of quartz. This joint research led to the development of the famous Bêta 21, but on the basis of its potential as a movement manufacturer, Longines had been conducting an independent study in parallel, more focused on the reasonably large-scale production of an electronic movement for wristwatches. After eighteen months of research, the physicists, watchmaking engineers, electronics technicians and mechanical experts of the Saint-Imier factory had succeeded in realising the costly “hourglass project”, a challenge to which few watchmaking companies at the time were able to rise.

The creation of a quartz electronic calibre was well off the beaten track of the technologies developed for many years by Longines – and indeed by the Swiss watchmaking industry –in spite of the incorporation of electronics into the field of sports timing from the 1950s onwards, and the production of electronic on-board chronometers in the mid 60s. A different mode of operation, dissimilar development strategies, production equipment which was different from traditional structures and an entirely different manufacturing method: it is possible to view the irruption of electronics on to the scene as a clear break in the dynamic of the technical progress of the watchmaking industry. However, in the face of foreign competition, the adoption of quartz seemed to be regarded by watchmakers as an onerous necessity, complementary to the traditional mechanical approach. In spite of the significant financing required, the manufacture approach which had inspired the creation of movements in Les Longines since the foundation of the factory had pushed the managers towards initiating the independent research project which was completed in 1969 when the company presented the 6512 calibre. Known as the Ultra-Quartz, this electronic movement for wristwatches was fitted with a quartz barrel and oscillated at a frequency of 9350 cycles per second. Powered by a 1.35V mercury battery, the Ultra-Quartz movement had a vibrating motor linked to the gears by means of a worm screw. It was referred to as a cybernetic movement in that it was made up of two mutually stabilising oscillating circuits. The design strategy behind the Ultra-Quartz revealed the technological choices implemented with the aim of simplifying the production of the movement, especially by avoiding having to integrate the circuit by the use of 14 transistors, 19 resistors and 7 capacitors. Finally, priority had to be given to its production. However, the rapid progress made in terms of the miniaturisation of electronic components and integrated circuits discredited the technical options selected by Longines for its Ultra-Quartz calibre, the first ever electronic movement for wristwatches to be marketed by a watch company.

Meanwhile, Longines was trying other means of breaking into the market, with products that went beyond traditional watchmaking. In 1972, Longines brought out an avant-garde style wristwatch produced jointly by the company at Saint-Imier, Ebauches SA and Texas Instrument Incorporated. Unlike other products of the winged-hourglass brand, this timepiece, which became known as the “Longines LCD” (liquid crystal display) had a digital display using a screen with liquid crystals. With precision guaranteed to about one minute per year, this watch gained the high distinction conferred by the IR100 (Annual Industrial Research Conference and Awards). This was the first time a Swiss company had received an award for the best products of scientific and industrial research.