====== Universal 281 ======
**Calibre 281** is a [[chronograph]] [[watch movement]] from [[Universal Genève]].

First produced in [[1932]], Calibre 281 is part of a family of important chronograph movements, including the first ever wristwatch chronograph with a calendar complication. These movements were produced with [[Martel]] and shared with [[Zenith]]. They featured Martel's variable diameter technology, which used larger [[plate]]s to increase the size of the movement from 12 [[ligne]] to 13.5 (also called 14) ligne.

The family used a [[Breguet hairspring]], had an 8-column [[pillar wheel]], and came in [[compax]] and [[tri-compax]] variants.

===== Variants =====
There were many variants on the basic Cal. 281 movement, and production lasted more than half a century. All were 4.58 mm high but diameter varied from 12 ligne to 13.5 ligne. All beat at 18,000 A/h and ran for 36 hours. The Cal. 38x variants have a [[flat hairspring]] rather than [[Breguet hairspring|Breguet]]. There were also later Cal. 48x versions.

Zenith named their versions of these calibres for their size in ligne.

  *Breguet hairspring
    *Universal Calibre 281/Zenith Calibre 122 - 12 ligne (also available in compax and tri-compax)
    *Universal Calibre 282 - 12.25 ligne
    *Universal Calibre 283/Zenith Calibre 136 - 13 ligne
    *Universal Calibre 284 - 13.5 ligne
  *Flat hairspring
    *Universal Calibre 381 - 12 ligne (also available in compax and tri-compax)
    *Universal Calibre 383 - 13 ligne
  *Later model
    *Universal Calibre 481

===== See also =====
  *[[http://forums.watchuseek.com/f27/short-history-martel-watch-co-zenith-chronographs-660565.html|A Short History of Martel Watch Co and Zenith Chronographs]]


<WRAP ud ud_mov>

**Description:**
  * [[Hand winding]]
  * [[Column wheel]] [[chronograph]]

**Functions:**
  * Hours, minutes
  * [[Small seconds]]
  * 60 second, 30 minute, 12 hour counters
  * Optional full calendar module
  * Day at 10 30
  * Date hand at 12 00 (set by pusher at 8 00)
  * Month at 1 30 (set by pusher at 10 15)
  * Moon phase at 12 00 (set by pusher at 9 45)

**Data:**
  * 12-13.5 [[ligne]]s
  * D 27-30.5 mm, H 4.58 mm
  * 17 [[jewels]]
  * 18,000 A/h
  * Power reserve 36 Hours

**Production period:**
  * [[1932]]-
</WRAP>

{{tag>Movements Manual_winding_movements Chronograph_movements Universal_calibres Column_wheel_chronograph_movements}}