download zenith el primero chronomaster original

The heart of the El Primero beats at a pace of 36,000 semi-oscillations per hour, i.e., 5 Hz, and enables the chronograph to measure elapsed intervals to the nearest 1/10 of a second. And the balance had a higher frequency than was usual in this era. The power reserve exceeded 48 hours, which was somewhat longer than other contemporary movements. This contributed to the caliber’s highly precise rate. A dry lubricant based on molybdenum sulfate was used for the first time. It measured 13.5 lignes in diameter and was a mere 6.5 mm tall.

This movement’s technological victory march was almost impossible to stop. 10, 1969, calling its new watch the “El Primero” (meaning “the first”). But Zenith and its partner Movado had managed to publicly announce the development of an automatic chronograph movement and show a working prototype at a press conference in Geneva on Jan. In Japan, Seiko was working on its own automatic chronograph movement, Caliber 6139, which was introduced to the Japanese market in May 1969. A leading role was played by Breitling, which collaborated with Heuer-Leonidas, Hamilton/Büren and Dubois Dépraz to develop a micro-rotor caliber that was unveiled simultaneously in Geneva, New York, Hong Kong, and Beirut in March 1969. In Switzerland, toward the end of the 1960s, two coalitions of watch manufacturers were hard at work developing the world’s first automatic chronograph movement. But it’s much less common for a watch movement to gain fame and, after more than 50 years, achieve legendary status. It’s not uncommon for a watch to become a classic. In this historical feature from the WatchTime archives, contributor Thomas Gronenthal takes a look at its development. Zenith’s El Primero automatic chronograph caliber - unveiled to the world just over 50 years ago, in 1969 - is regarded as one of the world’s best and most accurate movements.

Download zenith el primero chronomaster original