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The ETACHRON Regulator

The ETACHRON regulating system (and similar designs) use rotating "blocks" attached to the hairspring stud and a movable regulating arm. The regulator effectively shortens or lengthens the hairspring and can be rotated to maintain perfect contact with the spring. Similar systems are employed by many watches, some of which use other regulating and indexing systems.

ETACHRON has officially been available in four versions:

  1. With a pointer on the balance cock
  2. With an eccentric screw corrector on the balance cock
  3. With the Valjoux corrector on the balance cock
  4. With no pointer or screw corrector

This has lead to some confusion, with some sources claiming that only the movable stud and rotating block is "ETACHRON", since these are present on all such movements. But ETA documents are clear that all of these components are part of the ETACHRON system.

The simplest ETACHRON regulator on Cal. 2660

Chronoswiss C.121

Chronoswiss C.123

Chronoswiss C.124

Chronoswiss C.125

Chronoswiss C.127

DUW 3001

DUW 6101

ETA 2000-1

ETA 2094

ETA 2660

ETA 2671

ETA 2678

ETA 2681

ETA 2688

ETA 2801-2

ETA 2804-2

ETA 2824-2

ETA 2826-2

ETA 2834-2

ETA 2836-2

ETA 2846

ETA 2892A2

ETA 2893-1

ETA 2893-2

ETA 2893-3

ETA 2894-2

ETA 2895-2

ETA 2896

ETA 2897

ETA 6497-1

ETA 6497-2

ETA 6498-1

ETA 6498-2

ETA 7750

ETA 7751

ETA 7753

ETA 7754

NH 3020CS

Seiko 4R15

Seiko 4R16

Seiko 4R35

Seiko 4R36

Seiko 4R37

Seiko 4R38

Seiko 4R39

Seiko 4R57

Seiko 4R71

Seiko 6R15

Seiko 6R20

Seiko 6R21

Seiko 6R24

Seiko 6R27

Seiko 7S25

Seiko 7S26

Seiko 7S35

Seiko 7S36

Valgranges A07.111

Valgranges A07.161

Valgranges A07.171

Valgranges A07.211

Valgranges A07.231

Valgranges A07.L01