IWC 790

Template:File The 790 (and derivative 7901, 7902, 7912, 7922, 79320, and 75320) is an automatic chronograph movement produced by IWC based on the Valjoux 7750 ebauche since 1981.

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 790 family of movements and the basic architecture is the basis for today's 69000 family of movements.

The first use of a 7750 ebauche by IWC was the Cal. 790 of 1981. Produced for the Porsche Design chronographs built by IWC, it was a basic Valjoux 7750 with nickel plating by IWC. This movement was used through 1988.

Cal. 7902 started with a basic Valjoux 7750 before being disassembled by IWC. The original components were refinished and gold plated, and the movement was assembled and regulated. This movement was produced from 1988 through 1996. Cal. 7901 is essentially the same, but with the day indication removed. It was produced from 1991 through 1993.

In 1995, IWC began changing the regulation system from the original Valjoux "fine regulator" to the Etachron system. This movement was renamed Cal. 7912. In 1996, IWC switched to the Triovis regulator, renaming the movement Cal. 7922.

The movement plating was switched to nickel in 2005, with the movement renamed Cal. 79320. The jewel count was also updated at this time to 31. IWC began sourcing ebauches from Sellita in the 2010s. Although the specification remains the same, movements based on the Sellita SW 500 are called Cal. 75320. Starting in 2018, IWC began using their own in-house Cal. 69380 in new watches like the IWC Pilot's Watch Chronograph Spitfire. It retains the 6-9-12 subdial layout but moves small seconds to the 6:00 position.

Movement Family

• 790 (1981-1988) - Nickel-plated Valjoux 7750
• 7901 (1991-1993) - Gold-plated Valjoux 7750, date-only
• 7902 (1988-1996) - Gold-plated Valjoux 7750
• 7912 (1995-1996) - Gold-plated Valjoux 7750 with Etachron
• 7922 (1996-2005) - Gold-plated Valjoux 7750 with Triovis
• 79320 (2005-2010s) - Nickel-plated ETA 7750 with 31 jewels
• 75320 (2010s-present) - Nickel-plated Sellita SW 500 with 25 jewels

Description: Automatic movement based on Valjoux 7750 Bi-directional winding Functions: Hours, minutes, small seconds at 9:00 Chronograph with hour counter at 6:00 and minute counter at 12:00 Day and date windows at 3:00 Data: Ø 30 mm, 7.9 mm thick 25 or 31 jewels 28,800 A/h Power reserve 44 hours Production period: 1981-Present Successor: IWC 69380