Valjoux Cal. 7733 is a cam-switching chronograph movement based on the Venus 188. After Valjoux acquired Venus in 1966, the company took the affordable Venus Cal. 188 architecture and launched a new Valjoux-branded movement, Cal. 7730. The only notable change was the use of a mobile stud carrier. Cal. 7731 followed with a different balance cock.
The movement was thoroughly redesigned by Valjoux as the Cal. 7733, launched in 1969. The original excenter adjustable hammer was replaced by a rocker design in 1971. The shape of the hammer was modified again in 1974.
Three related movements were also created: Cal. 7734 added a date function, Cal. 7736 had an hour counter, and Cal. 7737 was a regatta timer. Cal. 7733 was also the forerunner for the automatic Valjoux 7750, one of the most famous and successful watch movements of all time.