Calibre 6512

Notes

Longines, which had long prided itself on its in-house manufacture of calibres, set itself an internal goal of producing an in-house quartz calibre by or before 1970. Internally this initiative was called the "Hourglass Project". The result was the 6512 which though it does use a quartz crystal as an element of its timing also uses principles of electronic movements to drive its creation. Essentially this movement has two oscillating components, a quartz crystal that vibrates at 9,350hz and an electric motor that operates at 170 hz. The quartz loop which is extremely stable is used to electro-mechanically regulate the electronic loop which is much less stable. This system was developed completely independently of the CEH Beta 21 project and operates on different principles. Though this novel approach did seem to be at least as reliable as the Beta 21, advancements in electronic circuit miniaturization would make this system obsolete in relatively short order.