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ETA 1023
Manual · 11.5‴ · Switzerland · 1945
Dimensions
25.94 mm
Height
—
Jewels
15
Power reserve
40h
Timegrapher
Beat rate
18,000bph
Frequency
2.5Hz
Reference: healthy amplitude ≈ 270–315° fully wound (>200° at 24 h); beat error ideally < 0.5 ms.
Movement
| Movement type |
Manual
Purely mechanical movements wound by hand via the crown, which tensions the mainspring to store energy. As the spring unwinds, it drives the gear train at a controlled rate set by the escapement and balance. Typical power reserves range from 38 to 80 hours, requiring daily or near-daily winding to keep the watch running.
|
|---|---|
| Winding type |
Stem Winding (Crown)
Winding the mainspring by turning the crown attached to the stem, transmitting torque through the winding pinion. Patented by Adrien Philippe in 1842, it replaced key winding and remains the standard manual winding method for both pocket watches and wristwatches.
|
| Setting type |
Stem Set (Crown Pull)
The dominant modern system: pulling the crown out to a setting position engages the hand-setting mechanism. Introduced in the late 19th century and refined into multi-position crowns (date, time, GMT). Used in virtually all modern wristwatches and most 20th-century pocket watches.
|
| Escapement type |
Swiss Lever
The undisputed standard of modern mechanical watchmaking. Through an elegant interplay between escape wheel, pallet fork, and balance, it delivers reliable impulses with the safety of 'draw' to keep the lever locked. Refined since the 18th century, it powers almost every quality mechanical wristwatch made today.
|
| Control type |
Balance Wheel
The heart of mechanical timepieces, the balance wheel is an oscillating component that, together with the hairspring, forms a harmonic oscillator regulating the gear train's pace. Its steady back-and-forth motion ensures the even release of energy from the mainspring, governing the watch's accuracy.
|
| Regulator type |
Pinned Regulator (or Index Regulator)
The most traditional regulator, consisting of a movable index pointer fitted with two curb pins (or a pin and a boot) that embrace the hairspring. Sliding the index along its scale changes the spring's active length, adjusting the rate. Simple, reliable, and easy to service, it remains the workhorse standard across countless mechanical movements.
|
Specifications
| Lignes | 11.5‴ |
|---|---|
| Shape |
Round
It is the most common form that we can find.
|
| Complications |
Sweep Second
Contrary to the ticking motion of quartz watches, the sweep second hand in mechanical watches moves smoothly around the dial, offering a visual representation of time flowing continuously. This has become synonymous with the precision and craft of mechanical horology.
,
Chronograph Stopwatch
Functionality meets style as this feature allows wearers to measure specific time intervals, embodying the blend of everyday utility with sophisticated design.
|
| Hand count | 3 |
| Hand sizes | 1.40 x 0.80mm |
| Further measures | Mounting Diameter (Dm): 25.6mm Stem height (T): 1.9mm Mounting Height (F): 0.5mm |
Origin & References
| Manufacturer | ETA |
|---|---|
| Country | Switzerland |
| Launch year | 1945 |
| COSC certified | No |
| Signature | ca. 1945: Swiss Made, 15 Rubis - ETA
(ETA 820, sub second) |
| US import codes |
|
Notes
Remarks: different bridge layouts (cf. ETA 810)
Other data: balance staff: U1522 (U893) Ronda specifies for all calibres of the family the staff Ronda 3585 with the dimensions the staff U1522. The staff U893 has just a 0.01mm smaller hairspring collet. So both are usable. stem: W606 mainspring / battery: Zf1319/1, 1.60 x 9.5 x 0.10 x 315mm balance staff ronda: 3585 (10,5-11,5) stem ronda: 420 (10,5) Mainspring: 1.600 x 8.500 x 0.110 x 280.000 mm
Other data: balance staff: U1522 (U893) Ronda specifies for all calibres of the family the staff Ronda 3585 with the dimensions the staff U1522. The staff U893 has just a 0.01mm smaller hairspring collet. So both are usable. stem: W606 mainspring / battery: Zf1319/1, 1.60 x 9.5 x 0.10 x 315mm balance staff ronda: 3585 (10,5-11,5) stem ronda: 420 (10,5) Mainspring: 1.600 x 8.500 x 0.110 x 280.000 mm
Family
Series 810 - 1023
810: 10.5" , sub second
816: 10.5" , sweep second
820: 11.5" , sub second
863: 11.25" , sweep second
864: 11.25" , sub second
960: 13.5" , sub second
961: 13.5" , sweep second
995: 12" , sub second
996: 12" , sweep second
997: 12.5" , sub second
998: 12.5" , sweep second
1023: 11.5" , sweep second
816: 10.5" , sweep second
820: 11.5" , sub second
863: 11.25" , sweep second
864: 11.25" , sub second
960: 13.5" , sub second
961: 13.5" , sweep second
995: 12" , sub second
996: 12" , sweep second
997: 12.5" , sub second
998: 12.5" , sweep second
1023: 11.5" , sweep second
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ETA 1022
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