Encyclopedia · Movements
Movement & calibre database
Technical records for landmark calibres — from railroad pocket watches to tuning-fork, quartz and Spring Drive movements. Select up to four to compare. For how the parts work, see the mechanism encyclopedia.
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Side-by-side comparison
| Specification | Omega calibre 861 / 1861 | Omega calibre 321 | Valjoux 7750 |
|---|---|---|---|
| Manufacturer | Omega (Lemania 1873 base) | Omega (Lemania 2310 base) | Valjoux (ETA, Swatch Group) |
| Type | Manual chronograph | Manual chronograph | Automatic chronograph |
| Winding | Manual | Manual | Automatic (unidirectional rotor) |
| Production | 1968–1996 (861); 1996–2019 (1861) | 1946–1968; re-introduced 2019 | 1974–present |
| Country | Switzerland | Switzerland | Switzerland |
| Diameter | 27 mm (12 lignes) | 27 mm (12 lignes) | 30 mm (13¼ lignes) |
| Height | 6.87 mm | Undocumented here | 7.9 mm |
| Jewels | 17 (861); 18 (1861) | 17 | 25 |
| Frequency | 21,600 vph (3 Hz) | 18,000 vph (2.5 Hz) | 28,800 vph (4 Hz) |
| Power reserve | c. 45 h | c. 44 h | c. 42–48 h |
| Complications | Cam-lever chronograph (30-minute, 12-hour counters) | Column-wheel chronograph with lateral clutch (30-minute, 12-hour counters) | Cam-actuated chronograph (30-minute and 12-hour counters); day-date |
| Status | Documented | Documented | Documented |