Technical sheet
The Swiss workhorse: self-winding, 4 Hz, center seconds and date.
Features
Going train
| Arbor | Wheel | Pinion | True speed |
|---|---|---|---|
| Mainspring barrel | 84 | — | 1 rev / 7 hours |
| Center wheel | 80 | 12 | 1 rev / hour |
| Third wheel | 75 | 10 | 8 rev / hour |
| Fourth (seconds) wheel | 84 | 10 | 1 rev / minute |
| Escape wheel | 20 | 7 | 12 rev / minute |
Disclaimer
An approximation of the ETA 2824-2 layout from public drawings and photographs, not a manufacturer-accurate replica. Bidirectional automatic winding, 28,800 vph (4 Hz), 25 jewels, Ø 25.60 mm (11½ lignes), 4.60 mm height, semi-instantaneous date with quick correction and stop-seconds are published ETA figures. Power reserve: 38 h is the figure in ETA’s 2009 technical communication and most specifications; ETA’s product page gives 42 h as typical. Tooth counts, wheel sizes, the barrel position, the outlines of the bridges hidden under the rotor and the seconds drive are an approximation; the tooth counts make the fourth wheel turn once a minute and the escape wheel match 28,800 vph. Parts are drawn larger than life for legibility and the stack is taller than the real 4.60 mm. The escapement motion is a kinematic model, not a physics simulation.
Sources