Tudor Big Block Chronograph

After the game-changing introduction of the Chronomatic and the El Primero automatic chronograph movements in 1969, it seemed as though every brand rushed to produce an automatic chronograph of their own. Heuer (along with partners Hamilton, Breitling, and Buren) were more than keen to share their creation within the Swiss watchmaking community. Zenith, protective of their El Primero movement, were reluctant to offer it to competitors, only granting it to Tudor's parent company in 1988 for the Daytona.  Therefore, there simply wasn't an alternative to the Chronomatic or El Primero--that is, until 1974, when Valjoux introduced perhaps the most ubiquitous modern-day automatic chronograph movement: the Valjoux 7750.  Valjoux had long been a stalwart of the Swiss watchmaking industry. Brands from Breitling to Heuer relied on the column wheel caliber Valjoux 72, for example, which has become a byword for desirability in the mercurial vintage chronograph market. So it's no surprise, then, t