====== IWC 79091 ======

{{wst>image_cr|IWC|79091}}

The **79091** is a [[grande complication]] movement produced by [[IWC]] based on the [[Valjoux 7750]] [[ebauche]] since [[1990]].

===== Details =====
The [[Valjoux 7750]] movement was extremely important to the resurgence of [[IWC]] and the basic design remains in use today. The company has used it for many important innovations since the 1980's, including a [[perpetual calendar]], [[rattrapante]], and [[grande complication]]. The 7750 [[ebauche]] was used for the [[IWC 7900|790 family of movements]] and the basic architecture is the basis for today's [[IWC 69000|69000 family of movements]].

In [[1985]], IWC surprised the world with the introduction of an innovative [[perpetual calendar]] movement, [[IWC 7906|Cal. 7906]]. Designed by the legendary [[Kurt Klaus]], this movement was much simpler to operate than previous perpetual calendars and was reliable and relatively affordable as well. The next major advancement for IWC was this **Cal. 79091**, a [[grande complication]] movement combining Klaus' perpetual calendar with a [[minute repeater]]. Introduced at the [[Basel Fair]] in [[1990]], the [[IWC Grande Complication 3770|Grande Complication, Ref. 3770]] was produced through [[2010]]. This movement has lived on, continuing in production in the [[IWC Grande Complication 9270|Ref. 9270]] and [[IWC Portugieser Grande Complication 3774|Portugieser Grande Complication, Ref. 3774]] and then [[IWC Portugieser Grande Complication 3776|Ref. 3776]], which remains in production. This is the last movement using Klaus' original perpetual calendar mechanism to remain in production as of [[2019]].

Cal. 79091 began with a [[Valjoux 7750]] [[ebauche]] before being disassembled and modified by IWC. The movement was refinished and plated with gold, then assembled and regulated by the company. The Klaus perpetual calendar and minute repeater mechanisms are added to the existing [[automatic chronograph]]. Unlike earlier complicated movements which beat slower, this Cal. 79091 runs at 28,800 A/h.

In [[1992]], IWC introduced "[[IWC Il Destriero Scafusia|Il Destriero Scafusia]]", another grande complication, which added a [[tourbillon]] and [[rattrapante]] function in [[IWC 18680|Cal. 18680]].

===== Applications =====
  * [[IWC Grande Complication 3770|Grande Complication, Ref. 3770]] (1991-2010)
    * [[IWC Grande Complication 9270|Grande Complication, Ref. 9270]] (1993-2010)
  * [[IWC Portugieser Grande Complication 3774|Portugieser Grande Complication, Ref. 3774]] (2010-2014)
    * [[IWC Portugieser Grande Complication 3776|Portugieser Grande Complication, Ref. 3776]] (2015-present)

<WRAP ud ud_mov>
**Description:**
  * [[Automatic chronograph]] [[minute repeater]] [[perpetual calendar]] movement based on [[Valjoux 7750]]
  * Bi-directional winding

**Functions:**
  * Hours, minutes, [[chronograph seconds]] central
  * [[Date by pointer]] at 3 00
  * [[Month by pointer]] and [[chronograph hours]] at 6 00
  * [[Year window]] at 7 30
  * [[Day by pointer]] and [[small seconds]] at 9 00
  * [[Chronograph minutes]] and [[moon phase indicator]] at 12 00
  * [[Minute repeater]] slide on left side

**Data:**
  * Ø 30 mm
  * 75 [[jewels]]
  * 28,800 A/h
  * [[Power reserve]] 44 hours

**Production period:**
  * [[1991]]-Present
</WRAP>

{{tag>Movements Automatic_movements Automatic_chronograph_movements Minute_repeater_movements Perpetual_calendar_movements Grande_complication_movements IWC_calibres Valjoux_7750}}