Valjoux 7750
ProbableThe most widely used automatic chronograph ever made, and the movement behind an enormous share of Swiss chronographs from the 1980s onward, including the first-generation Chronomat. Two identifying traits are visible without opening the watch: the sub-register layout at 6-9-12 rather than 3-6-9, and the unidirectional rotor's characteristic wobble, which is a property of the winding system rather than a fault.
Specifications
- Movement manufacturer
- Valjoux
- Frequency
- 28,800 vph (4 Hz)
- Jewels
- 25
- Power reserve
- 48 hours
- Winding
- automatic
- Complications
- Chronograph · Cam switching · Day · Date
Architecture
Automatic chronograph with cam switching and an oscillating-pinion clutch, designed in 1973 and produced in enormous numbers by Valjoux and later ETA. Three registers at 6, 9 and 12 with a day-date at 3 in the base execution.
Service practice
Universally available service parts. A rebuilt 7750 with generic components runs correctly and is an originality note rather than a finding.
Related calibers
Succeeded by
Breitling B01Derivative
Hublot HUB44Built on
Valjoux 7753
References using this caliber
- Breitling 81950Factory
Chronomat · Whole production
Provenance of this record
Sources & Evidence
Ranfft Watch Movement Archive
Dr. Roland Ranfft (archived and maintained by volunteers)
- Accessed
- 2026-08-18
Cited for
Last verified: Not yet reviewed