7750 movement power storage

What is a Valjoux 7750 movement?

The Valjoux 7750 is a uni-directional winding movement, consisting of a main-plate, calendar plate, and chronograph top plate. It operates using a coulisse –lever escapement, where levers push a cam back and forth to drive the stopwatch mechanism of the movement.

How do I remove the stem from a 7750 based movement?

To extract the stem from a 7750 based movement, pull the crown out two clicks to time-setting mode. Look for the detent button near the crown. Gently press this down with your tool, and slide the crown/stem out. Do not use too much force to avoid damaging the setting lever/setting lever spring.

When did the 7750 come out?

It was officially introduced t0 the watch world around 1973/1974 but after the first run was manufactured, the caliber wasn’t produced again until 1985 (thanks to mechanical timepieces gaining popularity once again). The 7750 was partially designed on a computer – a first for the watch industry.

What ETA caliber is 7750?

The ETA/Valjoux caliber 7750 is one of the most recognizable and widely used automatic chronograph watch movements. It was based on the manual wind Valjoux caliber 7733, which itself was based on the Venus 188. Today, it is part of the “Mecaline” line of ETA movements.

What is a Valjoux 7750?

Valjoux was a movement manufacturer that designed and produced the caliber 7750. Valjoux is now part of ETA. What used to be called the Valjoux 7750 is now called the ETA 7750, unless of course it is an original 7750 that was made by Valjoux before becoming part of ETA. ETA officially calls it the “ETA 7750” on their tech sheets and drawings.

How many jewels does a caliber 7750 have?

There are also manual wind calibers 7760 (12/6/9 subdials with day/date) and 7765 (12/9 subdials with date). Most modern examples of the caliber 7750 will have 25 jewels. The first versions had 17 jewels. There are other versions with 24 jewels. If you see plastic parts in your caliber 7750 watch movement, do not be alarmed.