Omega Chronostop - Genève
This is a rare and very specific Omega watch, it was design by Fernando Fontana with Raymond Thévenaz responsible for the technical aspects. This is a Chronostop, probably chronostop it's the most misunderstood of all omega watches, unlike conventional chronographs that record seconds, minutes, and hours with two or three subdials, the Chronostop was designed to be used for short interval timing -- less than one minute -- with a central hand for seconds and a single pusher. Chronostop was a premium model in 1970. The watch’s movement looks simple, but it is a high-accuracy, high-beat, high-quality engine, essentially a simpler version of the movement that powered the Speedmaster. Omega used two movements for its Chronostop models: the cal.920 (with a date), and the cal.865 (no date), this one it's the 920. It's also a manual-wind movement with 17 jewels, that run at a rapid 21,600 Bph. Only chronostops have this movement. The bracelet it's the same of the Omega Dynamics from the same period.
The case is amazing, it's a monobloc 41.5mm case composed of stainless steel. With modular lugs, a round profile, and a screwed-in caseback, the Chronostop 146.012 is a sports watch.
Caliber 920 provides a date indicator, and the seconds hand operates at will via a monopusher chronograph arrangement. The chronograph measures only durations of sixty seconds or less, and the hand will continue to circulate until stopped and reset. A plexiglas crystal is period-correct and includes the essential Omega logo at dead center above the hands.
The Omega bracelet is a 1153 with 138 end links. A folding clasp with adjustment options keeps the watch secure, but the bracelet and clasp show the signs of their age. Please examine all images of the watch carefully.
Omega caliber 920 is based on the Moonwatch caliber 861. This manual wind movement includes a 40 hour power reserve, monopusher chronograph, date, 21,600 vibration per hour rate, and 17 jewels. The chronograph operates by means of a cam system and a lateral clutch.
The project of this watch should date to 1967, with Raymond Thévenaz for the technical aspects and Fernando Fontana for the design. The case design is quite unusual, the movement comes out from the front, something like a monobloc case.
This is, as far as I know, the largest chronostop ever made, with a 42 mm.
The dial shows signs of age, as do the bracelet and case, but after all this is a vintage.
It's very hard to capture the hole essence of the watch just by looking at the photos photos, live it's really an amazing vintage jumbo watch, and it lookes great on wrist.